1
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Zhuang J, Shi S, Xu F. Cardiorespiratory failure induced by inhalation of aerosolized fentanyl in anesthetized rats. Respir Physiol Neurobiol 2024; 327:104300. [PMID: 39009328 DOI: 10.1016/j.resp.2024.104300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 06/24/2024] [Accepted: 07/07/2024] [Indexed: 07/17/2024]
Abstract
Intravenous rapid injection of fentanyl causes respiratory depression (severe apneas), leading to sudden death, which constitutes the deadliest drug reaction among overdoses of synthetic opioids. Here we asked whether acute inhalation of overdose fentanyl would also result in similar respiratory failure and death. The anesthetized and spontaneously breathing rats with tracheal cannulation were exposed to aerosolized fentanyl at 100 mg/m3 (FNTH) or 30 mg/m3 (FNTL) for 10 min. Minute ventilation (VE), electromyography (EMG) of the internal and external intercostal muscles and thyroarytenoid muscles (EMGII, EMGEI, and EMGTA), heart rate and arterial blood pressure were recorded. During the exposure, FNTH and FNTL immediately triggered bradypnea (40 % reduction, p < 0.05) with TE prolonged and then gradually decreased VE by 40 % (P < 0.05) after a brief VE recovery. The initial TE prolongation (apneas) were characterized by the cessation of EMGEI activity with enhanced tonic discharges of EMGTA and EMGII. After termination of the exposure, the cardiorespiratory responses to FNTL returned to the baseline values 30 min later, while those to FNTH were greatly exacerbated (P < 0.05), leading to ventilatory and cardiac arrest occurred 16.4 ± 4.7 min and 19.3 ± 4.5 min respectively after the onset of FNTH. The ventilatory arrest was featured by cessation of both EMGEI and EMGII and augmentation of tonic EMGTA. Our results suggest that acute exposure to an overdose of fentanyl aerosol leads to death through initially inducing a brief central and upper airway obstructive apnea as well as chest wall rigidity followed by gradual severe hypoventilation, bradycardia and hypotension, and eventual cardiorespiratory arrest in anesthetized rats.
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Affiliation(s)
- Jianguo Zhuang
- Department of Physiology, Lovelace Biomedical Research Institute, Albuquerque, NM 87108, United States
| | - Shan Shi
- Department of Physiology, Lovelace Biomedical Research Institute, Albuquerque, NM 87108, United States
| | - Fadi Xu
- Department of Physiology, Lovelace Biomedical Research Institute, Albuquerque, NM 87108, United States.
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2
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Baby SM, May WJ, Getsy PM, Coffee GA, Nakashe T, Bates JN, Levine A, Lewis SJ. Fentanyl activates opposing opioid and non-opioid receptor systems that control breathing. Front Pharmacol 2024; 15:1381073. [PMID: 38698814 PMCID: PMC11063261 DOI: 10.3389/fphar.2024.1381073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 03/08/2024] [Indexed: 05/05/2024] Open
Abstract
Fentanyl elicits profound disturbances in ventilatory control processes in humans and experimental animals. The traditional viewpoint with respect to fentanyl-induced respiratory depression is that once the effects on the frequency of breathing (Freq), tidal volume (TV), and minute ventilation (MV = Freq × TV) are resolved, then depression of breathing is no longer a concern. The results of the present study challenge this concept with findings, as they reveal that while the apparent inhibitory effects of fentanyl (75 μg/kg, IV) on Freq, TV, and MV in adult male rats were fully resolved within 15 min, many other fentanyl-induced responses were in full effect, including opposing effects on respiratory timing parameters. For example, although the effects on Freq were resolved at 15 min, inspiratory duration (Ti) and end inspiratory pause (EIP) were elevated, whereas expiratory duration (Te) and end expiratory pause (EEP) were diminished. Since the effects of fentanyl on TV had subsided fully at 15 min, it would be expected that the administration of an opioid receptor (OR) antagonist would have minimal effects if the effects of fentanyl on this and other parameters had resolved. We now report that the intravenous injection of a 1.0 mg/kg dose of the peripherally restricted OR antagonist, methyl-naloxone (naloxone methiodide, NLXmi), did not elicit arousal but elicited some relatively minor changes in Freq, TV, MV, Te, and EEP but pronounced changes in Ti and EIP. In contrast, the injection of a 2.5 mg/kg dose of NLXmi elicited pronounced arousal and dramatic changes in many variables, including Freq, TV, and MV, which were not associated with increases in non-apneic breathing events such as apneas. The two compelling conclusions from this study are as follows: 1) the blockade of central ORs produced by the 2.5 mg/kg dose of NLXmi elicits pronounced increases in Freq, TV, and MV in rats in which the effects of fentanyl had apparently resolved, and 2) it is apparent that fentanyl had induced the activation of two systems with counter-balancing effects on Freq and TV: one being an opioid receptor inhibitory system and the other being a non-OR excitatory system.
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Affiliation(s)
- Santhosh M. Baby
- Department of Drug Discovery, Galleon Pharmaceuticals, Inc., Horsham, PA, United States
| | - Walter J. May
- Pediatric Respiratory Medicine, University of Virginia School of Medicine, Charlottesville, VA, United States
| | - Paulina M. Getsy
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | - Gregory A. Coffee
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | - Tej Nakashe
- Department of Biological Sciences, Kent State University, Kent, OH, United States
| | - James N. Bates
- Department of Anesthesiology, University of Iowa Hospitals and Clinics, Iowa City, IO, United States
| | - Alan Levine
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, United States
| | - Stephen J. Lewis
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, United States
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3
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Thurston TS, Weavil JC, Georgescu VP, Wan HY, Birgenheier NM, Morrissey CK, Jessop JE, Amann M. The exercise pressor reflex - a pressure-raising mechanism with a limited role in regulating leg perfusion during locomotion in young healthy men. J Physiol 2023; 601:4557-4572. [PMID: 37698303 PMCID: PMC10592099 DOI: 10.1113/jp284870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 08/15/2023] [Indexed: 09/13/2023] Open
Abstract
We investigated the role of the exercise pressor reflex (EPR) in regulating the haemodynamic response to locomotor exercise. Eight healthy participants (23 ± 3 years,V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ : 49 ± 6 ml/kg/min) performed constant-load cycling exercise (∼36/43/52/98%V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ ; 4 min each) without (CTRL) and with (FENT) lumbar intrathecal fentanyl attenuating group III/IV locomotor muscle afferent feedback and, thus, the EPR. To avoid different respiratory muscle metaboreflex and arterial chemoreflex activation during FENT, subjects mimicked the ventilatory response recorded during CTRL. Arterial and leg perfusion pressure (femoral arterial and venous catheters), femoral blood flow (Doppler-ultrasound), microvascular quadriceps blood flow index (indocyanine green), cardiac output (inert gas breathing), and systemic and leg vascular conductance were quantified during exercise. There were no cardiovascular and ventilatory differences between conditions at rest. Pulmonary ventilation, arterial blood gases and oxyhaemoglobin saturation were not different during exercise. Furthermore, cardiac output (-2% to -12%), arterial pressure (-7% to -15%) and leg perfusion pressure (-8% to -22%) were lower, and systemic (up to 16%) and leg (up to 27%) vascular conductance were higher during FENT compared to CTRL. Leg blood flow, microvascular quadriceps blood flow index, and leg O2 -transport and utilization were not different between conditions (P > 0.5). These findings reflect a critical role of the EPR in the autonomic control of the heart, vasculature and, ultimately, arterial pressure during locomotor exercise. However, the lack of a net effect of the EPR on leg blood flow challenges the idea of this cardiovascular reflex as a key determinant of leg O2 -transport during locomotor exercise in healthy, young individuals. KEY POINTS: The role of the exercise pressor reflex (EPR) in regulating leg O2 -transport during human locomotion remains uncertain. We investigated the influence of the EPR on the cardiovascular response to cycling exercise. Lumbar intrathecal fentanyl was used to block group III/IV leg muscle afferents and debilitate the EPR at intensities ranging from 30% to 100%V ̇ O 2 max ${\dot V_{{{\mathrm{O}}_{\mathrm{2}}}{\mathrm{max}}}}$ . To avoid different respiratory muscle metaboreflex and arterial chemoreflex activation during exercise with blocked leg muscle afferents, subjects mimicked the ventilatory response recorded during control exercise. Afferent blockade increased leg and systemic vascular conductance, but reduced cardiac output and arterial-pressure, with no net effect on leg blood flow. The EPR influenced the cardiovascular response to cycling exercise by contributing to the autonomic control of the heart and vasculature, but did not affect leg blood flow. These findings challenge the idea of the EPR as a key determinant of leg O2 -transport during locomotor exercise in healthy, young individuals.
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Affiliation(s)
- Taylor S. Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
| | - Joshua C. Weavil
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT
| | - Vincent P. Georgescu
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT
| | - Hsuan-Yu Wan
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | | | | | - Jacob E. Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
| | - Markus Amann
- Department of Anesthesiology, University of Utah, Salt Lake City, UT
- Geriatric Research, Education, and Clinical Center, Salt Lake City VAMC, UT
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4
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Dubilet M, Gruenbaum BF, Semyonov M, Ishay SY, Osyntsov A, Friger M, Geftler A, Zlotnik A, Brotfain E. Erector Spinae Plane (ESP) Block for Postoperative Pain Management after Open Oncologic Abdominal Surgery. Pain Res Manag 2023; 2023:9010753. [PMID: 37360747 PMCID: PMC10287517 DOI: 10.1155/2023/9010753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 05/28/2023] [Accepted: 06/02/2023] [Indexed: 06/28/2023]
Abstract
Patients undergoing abdominal oncologic surgical procedures require particular surgical and anesthesiologic considerations. Traditional pain management, such as opiate treatment, continuous epidural analgesia, and non-opioid drugs, may have serious side effects in this patient population. We evaluated erector spinae plane (ESP) blocks for postoperative pain management following elective oncologic abdominal surgeries. In this single-center, prospective, and randomized study, we recruited 100 patients who underwent elective oncological abdominal surgery between December 2020 and January 2022 at Soroka University Medical Center in Beer Sheva, Israel. We compared postoperative pain levels in patients who were treated with a preincisional ESP block in addition to traditional pain management with intravenous opioids, non-steroidal anti-inflammatory drugs (NSAIDs), and acetaminophen, compared to patients who were only given traditional pain management (control). Patients who were treated with a preincisional ESP block demonstrated significantly lower Visual Analog Scale scores at 60 minutes and 4, 8, and 12 hours following the surgery, compared to the control group (p < 0.001). Accordingly, patients in the ESP group required less morphine from 60 minutes to 12 hours after surgery, but they required increased non-opioid postoperative analgesia management at 4, 8, and 12 hours after surgery (p from 0.002 to <0.001) compared to the control group. In this study, we found ESP blocks to be a safe, technically simple, and effective treatment for postoperative pain management after elective oncologic abdominal procedures.
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Affiliation(s)
- Michael Dubilet
- Department of Anesthesiology and Critical Care, General Intensive Care Unit, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Benjamin F. Gruenbaum
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Jacksonville, FL, USA
| | - Michael Semyonov
- Department of Anesthesiology and Critical Care, General Intensive Care Unit, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Shlomo Yaron Ishay
- Department of Cardiothoracic Surgery, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Anton Osyntsov
- Department of General Surgery B, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Michael Friger
- Department of Public Health, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Alexander Geftler
- Department of Orthopedic Surgery, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Alexander Zlotnik
- Department of Anesthesiology and Critical Care, General Intensive Care Unit, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Evgeni Brotfain
- Department of Anesthesiology and Critical Care, General Intensive Care Unit, Soroka Medical Center, Faculty of Health Science, Ben-Gurion University of the Negev, Beer Sheva, Israel
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5
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Bateman JT, Saunders SE, Levitt ES. Understanding and countering opioid-induced respiratory depression. Br J Pharmacol 2023; 180:813-828. [PMID: 34089181 PMCID: PMC8997313 DOI: 10.1111/bph.15580] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 05/06/2021] [Accepted: 05/23/2021] [Indexed: 02/06/2023] Open
Abstract
Respiratory depression is the proximal cause of death in opioid overdose, yet the mechanisms underlying this potentially fatal outcome are not well understood. The goal of this review is to provide a comprehensive understanding of the pharmacological mechanisms of opioid-induced respiratory depression, which could lead to improved therapeutic options to counter opioid overdose, as well as other detrimental effects of opioids on breathing. The development of tolerance in the respiratory system is also discussed, as are differences in the degree of respiratory depression caused by various opioid agonists. Finally, potential future therapeutic agents aimed at reversing or avoiding opioid-induced respiratory depression through non-opioid receptor targets are in development and could provide certain advantages over naloxone. By providing an overview of mechanisms and effects of opioids in the respiratory network, this review will benefit future research on countering opioid-induced respiratory depression. LINKED ARTICLES: This article is part of a themed issue on Advances in Opioid Pharmacology at the Time of the Opioid Epidemic. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v180.7/issuetoc.
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Affiliation(s)
- Jordan T Bateman
- Department of Pharmacology & Therapeutics, University of Florida, Gainesville, Florida, USA
| | - Sandy E Saunders
- Department of Pharmacology & Therapeutics, University of Florida, Gainesville, Florida, USA
| | - Erica S Levitt
- Department of Pharmacology & Therapeutics, University of Florida, Gainesville, Florida, USA
- Breathing Research and Therapeutics Center, University of Florida, Gainesville, Florida, USA
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6
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Getsy PM, Baby SM, Gruber RB, Gaston B, Lewis THJ, Grossfield A, Seckler JM, Hsieh YH, Bates JN, Lewis SJ. S-Nitroso-L-Cysteine Stereoselectively Blunts the Deleterious Effects of Fentanyl on Breathing While Augmenting Antinociception in Freely-Moving Rats. Front Pharmacol 2022; 13:892307. [PMID: 35721204 PMCID: PMC9199495 DOI: 10.3389/fphar.2022.892307] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 04/26/2022] [Indexed: 01/08/2023] Open
Abstract
Endogenous and exogenously administered S-nitrosothiols modulate the activities of central and peripheral systems that control breathing. We have unpublished data showing that the deleterious effects of morphine on arterial blood-gas chemistry (i.e., pH, pCO2, pO2, and sO2) and Alveolar-arterial gradient (i.e., index of gas exchange) were markedly diminished in anesthetized Sprague Dawley rats that received a continuous intravenous infusion of the endogenous S-nitrosothiol, S-nitroso-L-cysteine. The present study extends these findings by showing that unanesthetized adult male Sprague Dawley rats receiving an intravenous infusion of S-nitroso-L-cysteine (100 or 200 nmol/kg/min) markedly diminished the ability of intravenous injections of the potent synthetic opioid, fentanyl (10, 25, and 50 μg/kg), to depress the frequency of breathing, tidal volume, and minute ventilation. Our study also found that the ability of intravenously injected fentanyl (10, 25, and 50 μg/kg) to disturb eupneic breathing, which was measured as a marked increase of the non-eupneic breathing index, was substantially reduced in unanesthetized rats receiving intravenous infusions of S-nitroso-L-cysteine (100 or 200 nmol/kg/min). In contrast, the deleterious effects of fentanyl (10, 25, and 50 μg/kg) on frequency of breathing, tidal volume, minute ventilation and non-eupneic breathing index were fully expressed in rats receiving continuous infusions (200 nmol/kg/min) of the parent amino acid, L-cysteine, or the D-isomer, namely, S-nitroso-D-cysteine. In addition, the antinociceptive actions of the above doses of fentanyl as monitored by the tail-flick latency assay, were enhanced by S-nitroso-L-cysteine, but not L-cysteine or S-nitroso-D-cysteine. Taken together, these findings add to existing knowledge that S-nitroso-L-cysteine stereoselectively modulates the detrimental effects of opioids on breathing, and opens the door for mechanistic studies designed to establish whether the pharmacological actions of S-nitroso-L-cysteine involve signaling processes that include 1) the activation of plasma membrane ion channels and receptors, 2) selective intracellular entry of S-nitroso-L-cysteine, and/or 3) S-nitrosylation events. Whether alterations in the bioavailability and bioactivity of endogenous S-nitroso-L-cysteine is a key factor in determining the potency/efficacy of fentanyl on breathing is an intriguing question.
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Affiliation(s)
- Paulina M. Getsy
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | | | - Ryan B. Gruber
- Galleon Pharmaceuticals, Inc., Horsham, PA, United States
| | - Benjamin Gaston
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Tristan H. J. Lewis
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
| | - Alan Grossfield
- Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, NY, United States
| | - James M. Seckler
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, United States
| | - Yee-Hsee Hsieh
- Division of Pulmonary, Critical Care and Sleep Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - James N. Bates
- Department of Anesthesia, University of Iowa, Iowa City, IA, United States
| | - Stephen J. Lewis
- Department of Pediatrics, Case Western Reserve University, Cleveland, OH, United States
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH, United States
- Functional Electrical Stimulation Center, Case Western Reserve University, Cleveland, OH, United States
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7
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Affiliation(s)
- Toby N Weingarten
- Department of Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, Minnesota
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8
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Altree TJ, Eckert DJ. Obstructive sleep apnea endotypes and their postoperative relevance. Int Anesthesiol Clin 2022; 60:1-7. [PMID: 35125480 DOI: 10.1097/aia.0000000000000357] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Thomas J Altree
- Adelaide Institute for Sleep Health, Flinders Health and Medical Research Institute, Flinders University, Bedford Park, South Australia, Australia
- Respiratory and Sleep Services, Flinders Medical Centre, Southern Adelaide Local Health Network, Bedford Park, South Australia, Australia
| | - Danny J Eckert
- Adelaide Institute for Sleep Health, Flinders Health and Medical Research Institute, Flinders University, Bedford Park, South Australia, Australia
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9
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Cambruzzi M, Oostrom H, Deutsch J. Cheyne–Stokes respiration in two sheep during recovery from general anaesthesia for experimental convection enhanced drug delivery. VETERINARY RECORD CASE REPORTS 2022. [DOI: 10.1002/vrc2.233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Martina Cambruzzi
- Anaesthesia Department, Langford Veterinary Referral Hospital University of Bristol Langford UK
| | | | - Julia Deutsch
- Anaesthesia Department, Langford Veterinary Referral Hospital University of Bristol Langford UK
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10
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Pre-treatment with Tandospirone attenuates fentanyl-induced respiratory depression without affecting the analgesic effects of fentanyl in rodents. Neurosci Lett 2022; 771:136459. [PMID: 35041907 DOI: 10.1016/j.neulet.2022.136459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/10/2022] [Accepted: 01/11/2022] [Indexed: 12/13/2022]
Abstract
Opioid analgesics are widely used to treat acute, postoperative, and chronic pain. However, opioid receptor activation can result in severe respiratory depression. In this study, we demonstrated that Tandospirone (TS), a selective serotonin-1A receptor partial agonist, is effective against opioid-induced respiratory depression. Fentanyl was used to establish a respiratory depression model in rodents. We observed the effects of TS on respiratory depression in rats by using plethysmographic recordings and arterial oxygen saturation. In addition, we evaluated the effects of TS on fentanyl-induced sedation and analgesia by using the loss of righting reflex (LORR) and hot-plate tests, respectively. Rats (n = 5) were treated with TS or saline 5 min prior to fentanyl administration. TS [2 mg/kg, intravenous (i.v.)] dose-dependently attenuated fentanyl-induced respiratory depression versus saline + fentanyl group. Furthermore, pre-treatment with TS (2 mg/kg, i.v.) increased arterial oxygen saturation to 76.5 ± 2.0% at 5 min after fentanyl injection, compared with 35.9 ± 2.5% in saline pre-treated rats (P < 0.001), whereas the time to induction of LORR (P > 0.99) and duration of LORR (P = 0.95) did not differ between the "TS + fentanyl" and "saline + fentanyl" group. The antinociceptive effect of fentanyl was not affected by the administration of TS (P = 0.99) in mice (n = 10). In conclusion, we found that TS, a novel non-benzodiazepine anxiolytic/antidepressant drug, could attenuate severe fentanyl-induced respiratory depression and did not affect the analgesic/sedative effect of fentanyl. The clinical application of TS could significantly improve pain management.
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11
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Himmelwright RS, Dominguez JE. Postpartum Respiratory Depression. Anesthesiol Clin 2021; 39:687-709. [PMID: 34776104 DOI: 10.1016/j.anclin.2021.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Postpartum respiratory depression is a complex, multifactorial issue that encompasses a patient's baseline preexisting conditions, certain pregnancy-specific conditions or complications, as well as the iatrogenic element of various medications given in the peripartum period. In this review, we discuss many of these factors including obesity, sleep-disordered breathing, chronic lung disease, neuromuscular disorders, opioids, preeclampsia, peripartum cardiomyopathy, postpartum hemorrhage, amniotic fluid embolism, sepsis, acute respiratory distress syndrome (ARDS), and medications such as analgesics, sedatives, anesthetics, and magnesium. Current recommendations for screening, treatment, and prevention are also discussed.
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Affiliation(s)
| | - Jennifer E Dominguez
- Duke University Medical Center, DUMC 3094, MS#9, 2301 Erwin Road, Durham, NC 27710, USA.
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12
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Fentanyl causes naloxone-resistant vocal cord closure: A platform for testing opioid overdose treatments. Drug Alcohol Depend 2021; 227:108974. [PMID: 34492557 DOI: 10.1016/j.drugalcdep.2021.108974] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/16/2021] [Accepted: 07/17/2021] [Indexed: 12/14/2022]
Abstract
BACKGROUND High doses of the synthetic opioid fentanyl cause rapid and sustained vocal cord closure (VCC) leading to airway obstruction that prevents overdose victims from breathing. This airway effect is not caused by morphine-derived opiates (e.g. heroin), is distinct from respiratory depression, resistant to naloxone, and can be lethal. However, VCC has not been previously included in animal models of opioid overdose. METHODS Video laryngoscopy was used to monitor vocal cord movement in anesthetized Sprague-Dawley rats. Rats were administered saline, fentanyl (5, 25, or 50 μg/kg) or morphine (5 mg/kg) in an intravenous (IV) bolus delivered over a 10 s period. The mu opioid receptor (MOR) antagonist naloxone was administered as a pre-treatment (1 mg/kg, IV) 5 min prior to fentanyl (25 μg/kg) or a post-treatment (1 and 2 mg/kg) 1 min after fentanyl (25 μg/kg). RESULTS Fentanyl (25 and 50 μg/kg) caused sustained and lethal VCC within 10 s. Morphine (5 mg/kg) and fentanyl (5 μg/kg) caused only brief laryngospasm with full recovery. Pre-treatment with naloxone (1 mg/kg) prevented fentanyl-induced VCC, but naloxone (1 and 2 mg/kg) was unable to reverse VCC when administered after fentanyl. CONCLUSIONS These results indicate sustained VCC is a lethal physiological reaction, specific to fentanyl and resistant to naloxone treatment. While pre-treatment with naloxone prevented fentanyl-induced VCC, naloxone was unable to reverse the effect, suggesting a non-opioid receptor-mediated mechanism. These findings demonstrate the necessity of VCC inclusion in animal models of synthetic opioid overdose and the urgent need for more effective treatments for fentanyl-related overdoses.
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13
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Palkovic B, Marchenko V, Zuperku EJ, Stuth EAE, Stucke AG. Multi-Level Regulation of Opioid-Induced Respiratory Depression. Physiology (Bethesda) 2021; 35:391-404. [PMID: 33052772 DOI: 10.1152/physiol.00015.2020] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Opioids depress minute ventilation primarily by reducing respiratory rate. This results from direct effects on the preBötzinger Complex as well as from depression of the Parabrachial/Kölliker-Fuse Complex, which provides excitatory drive to preBötzinger Complex neurons mediating respiratory phase-switch. Opioids also depress awake drive from the forebrain and chemodrive.
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Affiliation(s)
- Barbara Palkovic
- Medical College of Wisconsin, Milwaukee, Wisconsin.,Faculty of Medicine, University of Osijek, Osijek, Croatia
| | | | - Edward J Zuperku
- Medical College of Wisconsin, Milwaukee, Wisconsin.,Zablocki VA Medical Center, Milwaukee, Wisconsin
| | - Eckehard A E Stuth
- Medical College of Wisconsin, Milwaukee, Wisconsin.,Children's Hospital of Wisconsin, Milwaukee, Wisconsin
| | - Astrid G Stucke
- Medical College of Wisconsin, Milwaukee, Wisconsin.,Children's Hospital of Wisconsin, Milwaukee, Wisconsin
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14
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Dose-dependent Respiratory Depression by Remifentanil in the Rabbit Parabrachial Nucleus/Kölliker-Fuse Complex and Pre-Bötzinger Complex. Anesthesiology 2021; 135:649-672. [PMID: 34352068 DOI: 10.1097/aln.0000000000003886] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND Recent studies showed partial reversal of opioid-induced respiratory depression in the pre-Bötzinger complex and the parabrachial nucleus/Kölliker-Fuse complex. The hypothesis for this study was that opioid antagonism in the parabrachial nucleus/Kölliker-Fuse complex plus pre-Bötzinger complex completely reverses respiratory depression from clinically relevant opioid concentrations. METHODS Experiments were performed in 48 adult, artificially ventilated, decerebrate rabbits. The authors decreased baseline respiratory rate ~50% with intravenous, "analgesic" remifentanil infusion or produced apnea with remifentanil boluses and investigated the reversal with naloxone microinjections (1 mM, 700 nl) into the Kölliker-Fuse nucleus, parabrachial nucleus, and pre-Bötzinger complex. In another group of animals, naloxone was injected only into the pre-Bötzinger complex to determine whether prior parabrachial nucleus/Kölliker-Fuse complex injection impacted the naloxone effect. Last, the µ-opioid receptor agonist [d-Ala,2N-MePhe,4Gly-ol]-enkephalin (100 μM, 700 nl) was injected into the parabrachial nucleus/Kölliker-Fuse complex. The data are presented as medians (25 to 75%). RESULTS Remifentanil infusion reduced the respiratory rate from 36 (31 to 40) to 16 (15 to 21) breaths/min. Naloxone microinjections into the bilateral Kölliker-Fuse nucleus, parabrachial nucleus, and pre-Bötzinger complex increased the rate to 17 (16 to 22, n = 19, P = 0.005), 23 (19 to 29, n = 19, P < 0.001), and 25 (22 to 28) breaths/min (n = 11, P < 0.001), respectively. Naloxone injection into the parabrachial nucleus/Kölliker-Fuse complex prevented apnea in 12 of 17 animals, increasing the respiratory rate to 10 (0 to 12) breaths/min (P < 0.001); subsequent pre-Bötzinger complex injection prevented apnea in all animals (13 [10 to 19] breaths/min, n = 12, P = 0.002). Naloxone injection into the pre-Bötzinger complex alone increased the respiratory rate to 21 (15 to 26) breaths/min during analgesic concentrations (n = 10, P = 0.008) but not during apnea (0 [0 to 0] breaths/min, n = 9, P = 0.500). [d-Ala,2N-MePhe,4Gly-ol]-enkephalin injection into the parabrachial nucleus/Kölliker-Fuse complex decreased respiratory rate to 3 (2 to 6) breaths/min. CONCLUSIONS Opioid reversal in the parabrachial nucleus/Kölliker-Fuse complex plus pre-Bötzinger complex only partially reversed respiratory depression from analgesic and even less from "apneic" opioid doses. The lack of recovery pointed to opioid-induced depression of respiratory drive that determines the activity of these areas. EDITOR’S PERSPECTIVE
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Baldo BA. Toxicities of opioid analgesics: respiratory depression, histamine release, hemodynamic changes, hypersensitivity, serotonin toxicity. Arch Toxicol 2021; 95:2627-2642. [PMID: 33974096 DOI: 10.1007/s00204-021-03068-2] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 04/29/2021] [Indexed: 11/30/2022]
Abstract
Opioid-induced respiratory depression is potentially life-threatening and often regarded as the main hazard of opioid use. Main cause of death is cardiorespiratory arrest with hypoxia and hypercapnia. Respiratory depression is mediated by opioid μ receptors expressed on respiratory neurons in the CNS. Studies on the major sites in the brainstem mediating respiratory rate suppression, the pre-Bӧtzinger complex and parabrachial complex (including the Kӧlliker Fuse nucleus), have yielded conflicting findings and interpretations but recent investigations involving deletion of μ receptors from neurons have led to greater consensus. Some opioid analgesic drugs are histamine releasers. The range of clinical effects of released histamine include increased cardiac output due to an increase in heart rate, increased force of myocardial contraction, and a dilatatory effect on small blood vessels leading to flushing, decreased vascular resistance and hypotension. Resultant hemodynamic changes do not necessarily relate directly to the concentration of histamine in plasma due to a range of variables including functional differences between mast cells and histamine-induced anaphylactoid reactions may occur less often than commonly believed. Opioid-induced histamine release rarely if ever provokes bronchospasm and histamine released by opioids in normal doses does not lead to anaphylactoid reactions or result in IgE-mediated reactions in normal patients. Hypersensitivities to opioids, mainly some skin reactions and occasional type I hypersensitivities, chiefly anaphylaxis and urticaria, are uncommon. Hypersensitivities to morphine, codeine, heroin, methadone, meperidine, fentanyl, remifentanil, buprenorphine, tramadol, and dextromethorphan are summarized. In 2016, the FDA issued a Drug Safety Communication concerning the association of opioids with serotonin syndrome, a toxicity associated with raised intra-synaptic concentrations of serotonin in the CNS, inhibition of serotonin reuptake, and activation of 5-HT receptors. Opioids may provoke serotonin toxicity especially if administered in conjunction with other serotonergic medications. The increasing use of opioid analgesics and widespread prescribing of antidepressants and psychiatric medicines, indicates the likelihood of an increased incidence of serotonin toxicity in opioid-treated patients.
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Affiliation(s)
- Brian A Baldo
- Molecular Immunology Unit, Kolling Institute of Medical Research, Royal North Shore Hospital of Sydney, Sydney, NSW, 2070, Australia.
- Department of Medicine, University of Sydney, Sydney, NSW, Australia.
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THE PULMONARY AND METABOLIC EFFECTS OF SUSPENSION BY THE FEET COMPARED WITH LATERAL RECUMBENCY IN IMMOBILIZED BLACK RHINOCEROSES (DICEROS BICORNIS) CAPTURED BY AERIAL DARTING. J Wildl Dis 2021; 57:357-367. [PMID: 33822147 DOI: 10.7589/2019-08-202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 05/07/2020] [Indexed: 11/20/2022]
Abstract
Aerial translocation of captured black rhinoceroses (Diceros bicornis) has been accomplished by suspending them by their feet. We expected this posture would compromise respiratory gas exchange more than would lateral recumbency. Because white rhinoceroses (Ceratotherium simum) immobilized with etorphine alone are hypermetabolic, with a high rate of carbon dioxide production (VCO2), we expected immobilized black rhinoceroses would also have a high VCO2. Twelve (nine male, three female; median age 8 yr old [range: 4-25]; median weight 1,137 kg [range: 804-1,234] body weight) wild black rhinoceroses were immobilized by aerial darting with etorphine and azaperone. The animals were in lateral recumbency or suspended by their feet from a crane for approximately 10 min before data were collected. Each rhinoceros received both treatments sequentially, in random order. Six were in lateral recumbency first and six were suspended first. All animals were substantially hypoxemic and hypercapnic in both postures. When suspended by the feet, mean arterial oxygen pressure (PaO2) was 42 mm Hg, 4 mm Hg greater than in lateral recumbency (P=0.030), and arterial carbon dioxide pressure (PaCO2) was 52 mm Hg, 3 mm Hg less than in lateral recumbency (P=0.016). Tidal volume and minute ventilation were similar between postures. The mean VCO2 was 2 mL/kg/min in both postures and was similar to, or marginally greater than, VCO2 predicted allometrically. Suspension by the feet for 10 min did not impair pulmonary function more than did lateral recumbency and apparently augmented gas exchange to a small degree relative to lateral recumbency. The biological importance in these animals of numerically small increments in PaO2 and decrements in PaCO2 with suspension by the feet is unknown. Black rhinoceroses immobilized with etorphine and azaperone were not as hypermetabolic as were white rhinoceroses immobilized with etorphine.
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Hasegawa M, Nozaki-Taguchi N, Shono K, Mizuno Y, Takai H, Sato Y, Isono S. Effects of opioids on respiration assessed by a contact-free unconstraint respiratory monitor with load cells under the bed in patients with advanced cancer. J Appl Physiol (1985) 2021; 130:1743-1753. [PMID: 33886386 DOI: 10.1152/japplphysiol.00904.2020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Nocturnal periodic breathing of chronic opioid users has been predominantly documented by the use of polysomnography. No previous studies have assessed the opioid effects of respiratory rhythms throughout the day without the use of physical restraint. We recently developed a contact-free unconstraint vital sign monitoring system with four load cells placed under the bed legs, which allows continuous measurements of respiratory change at the center of gravity on the bed. We aimed to reveal details of the patient's 24-h respiratory status under a monitoring system and to test the hypothesis that respiratory rhythm abnormalities are opioid dose-dependent and worsen during the night time. Continuous 48-h respiratory measurements were successfully performed in 51 patients with advanced cancer (12 opioid-free patients and 39 opioid-receiving patients). Medians of respiratory variables with minimal body movement artifacts were calculated for each 8-h split time period. Compared with opioid-free patients, opioid-receiving patients had slower respiratory rate with higher respiratory rate irregularity without changing tidal centroid shift regardless of the time period. Irregular ataxic breathing was only identified in opioid-receiving patients (33%, P = 0.023) whereas incidence rate of periodic breathing did not differ between the groups. Multivariate regression analyses revealed that opioid dose was an independent risk factor for occurrence of irregular breathing [odds ratio 1.81 (95% CI: 1.39-2.36), P < 0.001], and ataxic breathing [odds ratio 2.08 (95% CI: 1.60-2.71), P < 0.001]. Females developed the ataxic breathing at lower opioid dose compared with males. We conclude that respiratory rhythm irregularity is a predominant specific feature of opioid dose-dependent respiratory depression particularly in female patients with advanced cancer.NEW & NOTEWORTHY Through usage of a novel contact-free unconstraint vital sign monitoring system with four load cells placed under the bed legs allowing continuous measurements of respiratory changes of center of gravity on the bed, this study is the first to assess detailed respiratory characteristics throughout day and night periods without interference of daily activities in patients with advanced cancer receiving opioids. Respiratory rhythm irregularity is a predominant specific feature of opioid dose-dependent respiratory depression particularly in female patients with advanced cancer.
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Affiliation(s)
- Makoto Hasegawa
- Department of Anesthesiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Natsuko Nozaki-Taguchi
- Department of Anesthesiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Koyo Shono
- Department of Anesthesiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Yuko Mizuno
- Department of Anesthesiology and Palliative Medicine, Chiba University Hospital, Chiba, Japan
| | - Hiromichi Takai
- Department of Anesthesiology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Yasunori Sato
- Department of Preventive Medicine and Public Health, Keio University School of Medicine, Tokyo, Japan
| | - Shiroh Isono
- Department of Anesthesiology, Graduate School of Medicine, Chiba University, Chiba, Japan
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Shoemaker A, Steelman K, Srbu R, Bell HJ. Disparity in the effect of morphine on eupnea and gasping in anesthetized spontaneously breathing adult rats. Am J Physiol Regul Integr Comp Physiol 2020; 319:R526-R540. [PMID: 32903040 DOI: 10.1152/ajpregu.00031.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The goal of this study was to examine the effects of systemic morphine on the pattern and morphology of gasping breathing during respiratory autoresuscitation from transient anoxia. We hypothesized that systemic morphine levels sufficient to cause significant depression of eupnea would also cause depression of gasping breathing. Respiratory and cardiovascular variables were studied in 20 spontaneously breathing pentobarbital-anaesthetized adult male rats. Sham (saline) injections caused no significant change in resting respiratory or cardiovascular variables (n = 10 rats). Morphine, on the other hand, caused significant depression of eupneic breathing, with ventilation and peak inspiratory flow decreased by ∼30-60%, depending on the background condition (n = 10 rats). In contrast, morphine did not depress gasping breathing. Duration of primary apnea, time to restore eupnea, the number and amplitude of gasping breaths, average and maximum peak flows, and volume of gasping breaths were not significantly different postinjection in either condition. Blood pressures were all significantly lower following morphine injection at key time points in the process of autoresuscitation. Last, rate of successful recovery from anoxia was 80% in the morphine group (8/10 rats) compared with 100% (10/10 rats) in the sham group, postinjection. We conclude that the mechanisms and/or anatomic correlates underlying generation of gasping rhythm are distinct from those underlying eupnea, allowing gasping to remain robust to systemic morphine levels causing significant depression of eupnea. Morphine nevertheless decreases likelihood of recovery from transient anoxia, possibly as a result of decreased tissue perfusion pressures at critical time points during the process of respiratory autoresuscitation.
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Affiliation(s)
- Amanda Shoemaker
- Central Michigan University College of Medicine, Mt. Pleasant, Michigan
| | - Kevin Steelman
- Central Michigan University College of Medicine, Mt. Pleasant, Michigan
| | - Rebeka Srbu
- Central Michigan University College of Medicine, Mt. Pleasant, Michigan
| | - Harold J Bell
- Central Michigan University College of Medicine, Mt. Pleasant, Michigan
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Cinelli E, Bongianni F, Pantaleo T, Mutolo D. Activation of μ-opioid receptors differentially affects the preBötzinger Complex and neighbouring regions of the respiratory network in the adult rabbit. Respir Physiol Neurobiol 2020; 280:103482. [DOI: 10.1016/j.resp.2020.103482] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 06/05/2020] [Accepted: 06/12/2020] [Indexed: 11/25/2022]
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Wan HY, Weavil JC, Thurston TS, Georgescu VP, Bledsoe AD, Jessop JE, Buys MJ, Richardson RS, Amann M. The muscle reflex and chemoreflex interaction: ventilatory implications for the exercising human. J Appl Physiol (1985) 2020; 129:691-700. [PMID: 32816637 DOI: 10.1152/japplphysiol.00449.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
We examined the interactive influence of the muscle reflex (MR) and the chemoreflex (CR) on the ventilatory response to exercise. Eleven healthy subjects (5 women/6 men) completed three bouts of constant-load single-leg knee-extension exercise in a control trial and an identical trial conducted with lumbar intrathecal fentanyl to attenuate neural feedback from lower-limb group III/IV muscle afferents. The exercise during the two trials was performed while breathing ambient air ([Formula: see text] ~97%, [Formula: see text]~84 mmHg, [Formula: see text] ~32 mmHg, pH ~7.39), or under normocapnic hypoxia ([Formula: see text] ~79%, [Formula: see text] ~43 mmHg, [Formula: see text] ~33 mmHg, pH ~7.39) or normoxic hypercapnia ([Formula: see text] ~98%, [Formula: see text] ~105 mmHg, [Formula: see text] ~50 mmHg, pH ~7.26). During coactivation of the MR and the hypoxia-induced CR (O2-CR), minute ventilation (V̇e) and tidal volume (VT) were significantly greater compared with the sum of the responses to the activation of each reflex alone; there was no difference between the observed and summated responses in terms of breathing frequency (fB; P = 0.4). During coactivation of the MR and the hypercapnia-induced CR (CO2-CR), the observed ventilatory responses were similar to the summated responses of the reflexes (P ≥ 0.1). Therefore, the interaction between the MR and the O2-CR exerts a hyperadditive effect on V̇e and VT and an additive effect on fB, whereas the interaction between the MR and the CO2-CR is simply additive for all ventilatory parameters. These findings reveal that the MR:CR interaction further augments the ventilatory response to exercise in hypoxia.NEW & NOTEWORTHY Although the muscle reflex and the chemoreflex are recognized as independent feedback mechanisms regulating breathing during exercise, the ventilatory implications resulting from their interaction remain unclear. We quantified the individual and interactive effects of these reflexes during exercise and revealed differential modes of interaction. Importantly, the reflex interaction further amplifies the ventilatory response to exercise under hypoxemic conditions, highlighting a potential mechanism for optimizing arterial oxygenation in physically active humans at high altitude.
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Affiliation(s)
- Hsuan-Yu Wan
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Joshua C Weavil
- Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah
| | - Taylor S Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Vincent P Georgescu
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Michael J Buys
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Markus Amann
- Department of Anesthesiology, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Salt Lake City Veterans Affairs Medical Center, Utah.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah
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Severe Hypoxemia Prevents Spontaneous and Naloxone-induced Breathing Recovery after Fentanyl Overdose in Awake and Sedated Rats. Anesthesiology 2020; 132:1138-1150. [PMID: 32044798 DOI: 10.1097/aln.0000000000003156] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND As severe acute hypoxemia produces a rapid inhibition of the respiratory neuronal activity through a nonopioid mechanism, we have investigated in adult rats the effects of hypoxemia after fentanyl overdose-induced apnea on (1) autoresuscitation and (2) the antidotal effects of naloxone. METHODS In nonsedated rats, the breath-by-breath ventilatory and pulmonary gas exchange response to fentanyl overdose (300 µg · kg · min iv in 1 min) was determined in an open flow plethysmograph. The effects of inhaling air (nine rats) or a hypoxic mixture (fractional inspired oxygen tension between 7.3 and 11.3%, eight rats) on the ability to recover a spontaneous breathing rhythm and on the effects of naloxone (2 mg · kg) were investigated. In addition, arterial blood gases, arterial blood pressure, ventilation, and pulmonary gas exchange were determined in spontaneously breathing tracheostomized urethane-anesthetized rats in response to (1) fentanyl-induced hypoventilation (7 rats), (2) fentanyl-induced apnea (10 rats) in air and hyperoxia, and (3) isolated anoxic exposure (4 rats). Data are expressed as median and range. RESULTS In air-breathing nonsedated rats, fentanyl produced an apnea within 14 s (12 to 29 s). A spontaneous rhythmic activity always resumed after 85.4 s (33 to 141 s) consisting of a persistent low tidal volume and slow frequency rhythmic activity that rescued all animals. Naloxone, 10 min later, immediately restored the baseline level of ventilation. At fractional inspired oxygen tension less than 10%, fentanyl-induced apnea was irreversible despite a transient gasping pattern; the administration of naloxone had no effects. In sedated rats, when PaO2 reached 16 mmHg during fentanyl-induced apnea, no spontaneous recovery of breathing occurred and naloxone had no rescuing effect, despite circulation being maintained. CONCLUSIONS Hypoxia-induced ventilatory depression during fentanyl induced apnea (1) opposes the spontaneous emergence of a respiratory rhythm, which would have rescued the animals otherwise, and (2) prevents the effects of high dose naloxone.
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Torralva R, Eshleman AJ, Swanson TL, Schmachtenberg JL, Schutzer WE, Bloom SH, Wolfrum KM, Reed JF, Janowsky A. Fentanyl but not Morphine Interacts with Nonopioid Recombinant Human Neurotransmitter Receptors and Transporters. J Pharmacol Exp Ther 2020; 374:376-391. [PMID: 32513839 DOI: 10.1124/jpet.120.265561] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 06/01/2020] [Indexed: 12/13/2022] Open
Abstract
Synthetic opioids, including fentanyl and its analogs, have therapeutic efficacy in analgesia and anesthesia. However, their illicit use in the United States has increased and contributed to the number one cause of death for adults 18-50 years old. Fentanyl and the heroin metabolite morphine induce respiratory depression that can be treated with the μ opioid receptor (MOR) antagonist naloxone. With higher or more rapid dosing, fentanyl, more than morphine, causes chest wall rigidity and can also induce rapid onset laryngospasm. Because non-MORs could mediate differing clinical manifestations, we examined the interactions of fentanyl and morphine at recombinant human neurotransmitter transporters, G protein-coupled receptors, and the N-methyl-D-aspartate glutamate receptor. Both drugs were agonists at MOR, κ, and δ opioid receptors. Morphine had little or no affinity at other human receptors and transporters (K i or IC50 value >100 µM). However, fentanyl had K i values of 1407 and 1100 nM at α 1A and α 1B adrenoceptor subtypes, respectively, and K i values of 1049 and 1670 nM at dopamine D4.4 and D1 receptor subtypes, respectively; it also blocked [3H]neurotransmitter uptake by the vesicular monoamine transporter 2 (IC50 = 911 nM). Pharmacokinetic models indicate that these Ki and IC50 values are pharmacologically relevant. Fentanyl had little affinity for other receptors or transporters. Thus, noradrenergic disposition at specific receptor subtypes in relevant organs may play a role in respiratory and cardiothoracic effects of fentanyl. Data suggest that less selective fentanyl receptor pharmacology could play a role in the different clinical effects of morphine compared with fentanyl, including fentanyl-induced deaths after illicit use. SIGNIFICANCE STATEMENT: The synthetic opioid fentanyl induces different clinical effects, including rapid onset muscular rigidity, vocal cord closure, and rapid death, than the heroin metabolite morphine. Our data indicate for the first time that the two drugs have very different effects at recombinant human neurotransmitter receptors and transporters that might explain those clinical differences.
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Affiliation(s)
- Randy Torralva
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
| | - Amy J Eshleman
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
| | - Tracy L Swanson
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
| | - Jennifer L Schmachtenberg
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
| | - William E Schutzer
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
| | - Shelley H Bloom
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
| | - Katherine M Wolfrum
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
| | - John F Reed
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
| | - Aaron Janowsky
- Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.); Coda Research, Portland, Oregon (R.T.); Departments of Psychiatry (R.T., A.J.E., T.L.S., J.L.S., W.E.S., S.H.B., K.M.W., J.F.R., A.J.), Behavioral Neuroscience (A.J.E., A.J.), Oregon Health & Science University, Portland, Oregon; and The Methamphetamine Abuse Research Center, VA Portland Health Care System and Oregon Health & Science University, Portland, Oregon (W.E.S., A.J.)
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Ermer SC, Farney RJ, Johnson KB, Orr JA, Egan TD, Brewer LM. An Automated Algorithm Incorporating Poincaré Analysis Can Quantify the Severity of Opioid-Induced Ataxic Breathing. Anesth Analg 2020; 130:1147-1156. [DOI: 10.1213/ane.0000000000004498] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wan HY, Weavil JC, Thurston TS, Georgescu VP, Hureau TJ, Bledsoe AD, Buys MJ, Jessop JE, Richardson RS, Amann M. The exercise pressor reflex and chemoreflex interaction: cardiovascular implications for the exercising human. J Physiol 2020; 598:2311-2321. [PMID: 32170732 DOI: 10.1113/jp279456] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 03/10/2020] [Indexed: 01/11/2023] Open
Abstract
KEY POINTS Although the exercise pressor reflex (EPR) and the chemoreflex (CR) are recognized for their sympathoexcitatory effect, the cardiovascular implication of their interaction remains elusive. We quantified the individual and interactive cardiovascular consequences of these reflexes during exercise and revealed various modes of interaction. The EPR and hypoxia-induced CR interaction is hyper-additive for blood pressure and heart rate (responses during co-activation of the two reflexes are greater than the summation of the responses evoked by each reflex) and hypo-additive for peripheral haemodynamics (responses during co-activation of the reflexes are smaller than the summated responses). The EPR and hypercapnia-induced CR interaction results in a simple addition of the individual responses to each reflex (i.e. additive interaction). Collectively, EPR:CR co-activation results in significant cardiovascular interactions with restriction in peripheral haemodynamics, resulting from the EPR:CR interaction in hypoxia, likely having the most crucial impact on the functional capacity of an exercising human. ABSTRACT We investigated the interactive effect of the exercise pressor reflex (EPR) and the chemoreflex (CR) on the cardiovascular response to exercise. Eleven healthy participants (5 females) completed a total of six bouts of single-leg knee-extension exercise (60% peak work rate, 4 min each) either with or without lumbar intrathecal fentanyl to attenuate group III/IV afferent feedback from lower limbs to modify the EPR, while breathing either ambient air, normocapnic hypoxia (Sa O2 ∼79%, Pa O2 ∼43 mmHg, Pa CO2 ∼33 mmHg, pH ∼7.39), or normoxic hypercapnia (Sa O2 ∼98%, Pa O2 ∼105 mmHg, Pa CO2 ∼50 mmHg, pH ∼7.26) to modify the CR. During co-activation of the EPR and the hypoxia-induced CR (O2 -CR), mean arterial pressure and heart rate were significantly greater, whereas leg blood flow and leg vascular conductance were significantly lower than the summation of the responses evoked by each reflex alone. During co-activation of the EPR and the hypercapnia-induced CR (CO2 -CR), the haemodynamic responses were not different from the summated responses to each reflex response alone (P ≥ 0.1). Therefore, while the interaction resulting from the EPR:O2 -CR co-activation is hyper-additive for blood pressure and heart rate, and hypo-additive for peripheral haemodynamics, the interaction resulting from the EPR:CO2 -CR co-activation is simply additive for all cardiovascular parameters. Thus, EPR:CR co-activation results in significant interactions between cardiovascular reflexes, with the impact differing when the CR activation is achieved by hypoxia or hypercapnia. Since the EPR:CR co-activation with hypoxia potentiates the pressor response and restricts blood flow to contracting muscles, this interaction entails the most functional impact on an exercising human.
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Affiliation(s)
- Hsuan-Yu Wan
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Joshua C Weavil
- Geriatric Research, Education, and Clinical Center, Salt Lake City, UT, VAMC, USA
| | - Taylor S Thurston
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Vincent P Georgescu
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA
| | - Thomas J Hureau
- Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Amber D Bledsoe
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Michael J Buys
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Jacob E Jessop
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA
| | - Russell S Richardson
- Geriatric Research, Education, and Clinical Center, Salt Lake City, UT, VAMC, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
| | - Markus Amann
- Department of Anesthesiology, University of Utah, Salt Lake City, UT, USA.,Geriatric Research, Education, and Clinical Center, Salt Lake City, UT, VAMC, USA.,Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, USA
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Martins RT, Carberry JC, Wang D, Rowsell L, Grunstein RR, Eckert DJ. Morphine alters respiratory control but not other key obstructive sleep apnoea phenotypes: a randomised trial. Eur Respir J 2020; 55:13993003.01344-2019. [DOI: 10.1183/13993003.01344-2019] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 02/25/2020] [Indexed: 11/05/2022]
Abstract
Accidental opioid-related deaths are increasing. These often occur during sleep. Opioids such as morphine may worsen obstructive sleep apnoea (OSA). Thus, people with OSA may be at greater risk of harm from morphine. Possible mechanisms include respiratory depression and reductions in drive to the pharyngeal muscles to increase upper airway collapsibility. However, the effects of morphine on the four key phenotypic causes of OSA (upper airway collapsibility (pharyngeal critical closure pressure; Pcrit), pharyngeal muscle responsiveness, respiratory arousal threshold and ventilatory control (loop gain) during sleep) are unknown.21 males with OSA (apnoea–hypopnoea index range 7–67 events·h−1) were studied on two nights (1-week washout) according to a double-blind, randomised, cross-over design (ACTRN12613000858796). Participants received 40 mg of MS-Contin on one visit and placebo on the other. Brief reductions in continuous positive airway pressure (CPAP) from the therapeutic level were delivered to induce airflow limitation during non-rapid eye movement (REM) sleep to quantify the four phenotypic traits. Carbon dioxide was delivered via nasal mask on therapeutic CPAP to quantify hypercapnic ventilatory responses during non-REM sleep.Compared to placebo, 40 mg of morphine did not change Pcrit (−0.1±2.4 versus −0.4±2.2 cmH2O, p=0.58), genioglossus muscle responsiveness (−2.2 (−0.87 to −5.4) versus −1.2 (−0.3 to −3.5) μV·cmH2O−1, p=0.22) or arousal threshold (−16.7±6.8 versus −15.4±6.0 cmH2O, p=0.41), but did reduce loop gain (−10.1±2.6 versus −4.4±2.1, p=0.04) and hypercapnic ventilatory responses (7.3±1.2 versus 6.1±1.5 L·min−1, p=0.006).Concordant with recent clinical findings, 40 mg of MS-Contin does not systematically impair airway collapsibility, pharyngeal muscle responsiveness or the arousal threshold in moderately severe OSA patients. However, consistent with blunted chemosensitivity, ventilatory control is altered.
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Perekopskiy D, Afzal A, Jackson SN, Muller L, Woods AS, Kiyatkin EA. The Role of Peripheral Opioid Receptors in Triggering Heroin-induced Brain Hypoxia. Sci Rep 2020; 10:833. [PMID: 31964994 PMCID: PMC6972941 DOI: 10.1038/s41598-020-57768-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 01/06/2020] [Indexed: 12/21/2022] Open
Abstract
While it is known that opioid receptors (ORs) are densely expressed in both the brain and periphery, it is widely accepted that hypoxic effects of opioids result solely from their direct action in the CNS. To examine the role of peripheral ORs in triggering brain hypoxia, we used oxygen sensors in freely moving rats to examine how naloxone-HCl and naloxone-methiodide, the latter which is commonly believed to be peripherally restricted, affect brain oxygen responses induced by intravenous heroin at low, human-relevant doses. Similar to naloxone-HCl, naloxone-methiodide at a relatively low dose (2 mg/kg) fully blocked heroin-induced decreases in brain oxygen levels. As measured by mass spectrometry, naloxone-methiodide was found to be ~40-fold less permeable than naloxone-HCl across the blood-brain barrier, thus acting as a selective blocker of peripheral ORs. Despite this selectivity, a low but detectable amount of naloxone was found in brain tissue after naloxone-methiodide administration, potentially influencing our results. Therefore, we examined the effects of naloxone-methiodide at a very low dose (0.2 mg/kg; at which naloxone was undetectable in brain tissue) and found that this drug still powerfully attenuates heroin-induced brain oxygen responses. These data demonstrate the role of peripheral ORs in triggering heroin-induced respiratory depression and subsequent brain hypoxia.
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Affiliation(s)
- David Perekopskiy
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Anum Afzal
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Shelley N Jackson
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Ludovic Muller
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Amina S Woods
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA
| | - Eugene A Kiyatkin
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA.
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Kölliker-Fuse/Parabrachial complex mu opioid receptors contribute to fentanyl-induced apnea and respiratory rate depression. Respir Physiol Neurobiol 2020; 275:103388. [PMID: 31953234 DOI: 10.1016/j.resp.2020.103388] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 11/05/2019] [Accepted: 01/13/2020] [Indexed: 12/19/2022]
Abstract
Overdoses caused by the opioid agonist fentanyl have increased exponentially in recent years. Identifying mechanisms to counter progression to fatal respiratory apnea during opioid overdose is desirable, but difficult to study in vivo. The pontine Kölliker-Fuse/Parabrachial complex (KF/PB) provides respiratory drive and contains opioid-sensitive neurons. The contribution of the KF/PB complex to fentanyl-induced apnea was investigated using the in situ arterially perfused preparation of rat. Systemic application of fentanyl resulted in concentration-dependent respiratory disturbances. At low concentrations, respiratory rate slowed and subsequently transitioned to an apneustic-like, 2-phase pattern. Higher concentrations caused prolonged apnea, interrupted by occasional apneustic-like bursts. Application of CTAP, a selective mu opioid receptor antagonist, directly into the KF/PB complex reversed and prevented fentanyl-induced apnea by increasing the frequency of apneustic-like bursting. These results demonstrate that countering opioid effects in the KF/PB complex is sufficient to restore phasic respiratory output at a rate similar to pre-fentanyl conditions, which could be beneficial in opioid overdose.
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Varga AG, Reid BT, Kieffer BL, Levitt ES. Differential impact of two critical respiratory centres in opioid-induced respiratory depression in awake mice. J Physiol 2020; 598:189-205. [PMID: 31589332 PMCID: PMC6938533 DOI: 10.1113/jp278612] [Citation(s) in RCA: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/03/2019] [Indexed: 12/29/2022] Open
Abstract
KEY POINTS The main cause of death from opioid overdose is respiratory depression due to the activation of µ-opioid receptors (MORs). We conditionally deleted MORs from neurons in two key areas of the brainstem respiratory circuitry (the Kölliker-Fuse nucleus (KF) and pre-Bötzinger complex (preBötC)) to determine their role in opioid-induced respiratory disturbances in adult, awake mice. Deletion of MORs from KF neurons attenuated respiratory rate depression at all doses of morphine. Deletion of MORs from preBötC neurons attenuated rate depression at the low dose, but had no effect on rate following high doses of morphine. Instead, high doses of morphine increased the occurrence of apnoeas. The results indicate that opioids affect distributed key areas of the respiratory network in a dose-dependent manner and countering the respiratory effects of high dose opioids via the KF may be an effective approach to combat overdose. ABSTRACT The primary cause of death from opioid overdose is respiratory failure. High doses of opioids cause severe rate depression and increased risk of fatal apnoea, which correlate with increasing irregularities in breathing pattern. µ-Opioid receptors (MORs) are widely distributed throughout the brainstem respiratory network, but the mechanisms underlying respiratory depression are poorly understood. The medullary pre-Bötzinger complex (preBötC) and the pontine Kölliker-Fuse nucleus (KF) are considered critical for inducing opioid-related respiratory disturbances. We used a conditional knockout approach to investigate the roles and relative contribution of MORs in KF and preBötC neurons in opioid-induced respiratory depression in awake adult mice. The results revealed dose-dependent and region-specific opioid effects on the control of both respiratory rate and pattern. Respiratory depression induced by an anti-nociceptive dose of morphine was significantly attenuated following deletion of MORs from either the KF or the preBötC, suggesting cumulative network effects on respiratory rate control at low opioid doses. Deletion of MORs from KF neurons also relieved rate depression at near-maximal respiratory depressant doses of morphine. Meanwhile, deletion of MORs from the preBötC had no effect on rate following administration of high doses of morphine. Instead, a severe ataxic breathing pattern emerged with many apnoeas. We conclude that opioids affect distributed areas of the respiratory network and opioid-induced respiratory depression cannot be attributed to only one area in isolation. However, countering the effects of near maximal respiratory depressant doses of opioids in the KF may be a powerful approach to combat opioid overdose.
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Affiliation(s)
- Adrienn G. Varga
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL 32610
- Center for Respiratory Research and Rehabilitation, Department of Physical Therapy, University of Florida, Gainesville, FL 32610
| | - Brandon T. Reid
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL 32610
| | | | - Erica S. Levitt
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL 32610
- Center for Respiratory Research and Rehabilitation, Department of Physical Therapy, University of Florida, Gainesville, FL 32610
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29
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Wu JG, Wang D, Rowsell L, Wong KK, Yee BJ, Nguyen CD, Han F, Hilmisson H, Thomas RJ, Grunstein RR. The effect of acute exposure to morphine on breathing variability and cardiopulmonary coupling in men with obstructive sleep apnea: A randomized controlled trial. J Sleep Res 2019; 29:e12930. [DOI: 10.1111/jsr.12930] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/19/2019] [Accepted: 09/17/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Justin G.‐A. Wu
- Centre for Integrated Research and Understanding of Sleep (CIRUS) Woolcock Institute of Medical Research Sydney Medical School The University of Sydney Sydney NSW Australia
| | - David Wang
- Centre for Integrated Research and Understanding of Sleep (CIRUS) Woolcock Institute of Medical Research Sydney Medical School The University of Sydney Sydney NSW Australia
- Department of Respiratory and Sleep Medicine Royal Prince Alfred Hospital Sydney NSW Australia
| | - Luke Rowsell
- Centre for Integrated Research and Understanding of Sleep (CIRUS) Woolcock Institute of Medical Research Sydney Medical School The University of Sydney Sydney NSW Australia
| | - Keith K. Wong
- Centre for Integrated Research and Understanding of Sleep (CIRUS) Woolcock Institute of Medical Research Sydney Medical School The University of Sydney Sydney NSW Australia
- Department of Respiratory and Sleep Medicine Royal Prince Alfred Hospital Sydney NSW Australia
| | - Brendon J. Yee
- Centre for Integrated Research and Understanding of Sleep (CIRUS) Woolcock Institute of Medical Research Sydney Medical School The University of Sydney Sydney NSW Australia
- Department of Respiratory and Sleep Medicine Royal Prince Alfred Hospital Sydney NSW Australia
| | - Chinh D. Nguyen
- Centre for Integrated Research and Understanding of Sleep (CIRUS) Woolcock Institute of Medical Research Sydney Medical School The University of Sydney Sydney NSW Australia
| | - Fang Han
- Department of Respiratory Medicine Peking University People's Hospital Beijing China
| | | | - Robert J. Thomas
- Beth Israel Deaconess Medical Center Harvard Medical School Boston MA USA
| | - Ronald R. Grunstein
- Centre for Integrated Research and Understanding of Sleep (CIRUS) Woolcock Institute of Medical Research Sydney Medical School The University of Sydney Sydney NSW Australia
- Department of Respiratory and Sleep Medicine Royal Prince Alfred Hospital Sydney NSW Australia
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Torralva R, Janowsky A. Noradrenergic Mechanisms in Fentanyl-Mediated Rapid Death Explain Failure of Naloxone in the Opioid Crisis. J Pharmacol Exp Ther 2019; 371:453-475. [PMID: 31492824 DOI: 10.1124/jpet.119.258566] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 09/03/2019] [Indexed: 12/25/2022] Open
Abstract
In December 2018, the Centers for Disease Control declared fentanyl the deadliest drug in America. Opioid overdose is the single greatest cause of death in the United States adult population (ages 18-50), and fentanyl and its analogs [fentanyl/fentanyl analogs (F/FAs)] are currently involved in >50% of these deaths. Anesthesiologists in the United States were introduced to fentanyl in the early 1970s when it revolutionized surgical anesthesia by combining profound analgesia with hemodynamic stability. However, they quickly had to master its unique side effect. F/FAs can produce profound rigidity in the diaphragm, chest wall and upper airway within an extremely narrow dosing range. This clinical effect was called wooden chest syndrome (WCS) by anesthesiologists and is not commonly known outside of anesthesiology or to clinicians or researchers in addiction research/medicine. WCS is almost routinely fatal without expert airway management. This review provides relevant clinical human pharmacology and animal data demonstrating that the significant increase in the number of F/FA-induced deaths may involve α-adrenergic and cholinergic receptor-mediated mechanical failure of the respiratory and cardiovascular systems with rapid development of rigidity and airway closure. Although morphine and its prodrug, heroin, can cause mild rigidity in abdominal muscles at high doses, neither presents with the distinct and rapid respiratory failure seen with F/FA-induced WCS, separating F/FA overdose from the slower onset of respiratory depression caused by morphine-derived alkaloids. This distinction has significant consequences for the design and implementation of new pharmacologic strategies to effectively prevent F/FA-induced death. SIGNIFICANCE STATEMENT: Deaths from fentanyl and F/FAs are increasing in spite of availability and awareness of the opioid reversal drug naloxone. This article reviews literature suggesting that naloxone may be ineffective against centrally mediated noradrenergic and cholinergic effects of F/FAs, which clinically manifest as severe muscle rigidity and airway compromise (e.g., wooden chest syndrome) that is rapid and distinct from respiratory depression seen with morphine-derived alkaloids. A physiologic model is proposed and implications for new drug development and treatment are discussed.
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Affiliation(s)
- Randy Torralva
- CODA Inc., Research Department, Portland, Oregon (R.T.); Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.); and Department of Psychiatry, Oregon Health & Science University, Portland, Oregon (R.T., A.J.)
| | - Aaron Janowsky
- CODA Inc., Research Department, Portland, Oregon (R.T.); Research Service, VA Portland Health Care System, Portland, Oregon (R.T., A.J.); and Department of Psychiatry, Oregon Health & Science University, Portland, Oregon (R.T., A.J.)
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31
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Ayad S, Khanna AK, Iqbal SU, Singla N. Characterisation and monitoring of postoperative respiratory depression: current approaches and future considerations. Br J Anaesth 2019; 123:378-391. [DOI: 10.1016/j.bja.2019.05.044] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 05/06/2019] [Accepted: 05/24/2019] [Indexed: 01/19/2023] Open
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Noto T, Zhou G, Schuele S, Templer J, Zelano C. Automated analysis of breathing waveforms using BreathMetrics: a respiratory signal processing toolbox. Chem Senses 2018; 43:583-597. [PMID: 29985980 PMCID: PMC6150778 DOI: 10.1093/chemse/bjy045] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Nasal inhalation is the basis of olfactory perception and drives neural activity in olfactory and limbic brain regions. Therefore, our ability to investigate the neural underpinnings of olfaction and respiration can only be as good as our ability to characterize features of respiratory behavior. However, recordings of natural breathing are inherently nonstationary, nonsinusoidal, and idiosyncratic making feature extraction difficult to automate. The absence of a freely available computational tool for characterizing respiratory behavior is a hindrance to many facets of olfactory and respiratory neuroscience. To solve this problem, we developed BreathMetrics, an open-source tool that automatically extracts the full set of features embedded in human nasal airflow recordings. Here, we rigorously validate BreathMetrics' feature estimation accuracy on multiple nasal airflow datasets, intracranial electrophysiological recordings of human olfactory cortex, and computational simulations of breathing signals. We hope this tool will allow researchers to ask new questions about how respiration relates to body, brain, and behavior.
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Affiliation(s)
- Torben Noto
- Department of Neurology, Northwestern University Feinberg School of Medicine, Ward, Chicago, IL, USA
| | - Guangyu Zhou
- Department of Neurology, Northwestern University Feinberg School of Medicine, Ward, Chicago, IL, USA
| | - Stephan Schuele
- Department of Neurology, Northwestern University Feinberg School of Medicine, Ward, Chicago, IL, USA
| | - Jessica Templer
- Department of Neurology, Northwestern University Feinberg School of Medicine, Ward, Chicago, IL, USA
| | - Christina Zelano
- Department of Neurology, Northwestern University Feinberg School of Medicine, Ward, Chicago, IL, USA
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Tomazini Martins R, Carberry JC, Gandevia SC, Butler JE, Eckert DJ. Effects of morphine on respiratory load detection, load magnitude perception, and tactile sensation in obstructive sleep apnea. J Appl Physiol (1985) 2018; 125:393-400. [DOI: 10.1152/japplphysiol.00065.2018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Pharyngeal and respiratory sensation is impaired in obstructive sleep apnea (OSA). Opioids may further diminish respiratory sensation. Thus protective pharyngeal neuromuscular and arousal responses to airway occlusion that rely on respiratory sensation could be impaired with opioids to worsen OSA severity. However, little is known about the effects of opioids on upper airway and respiratory sensation in people with OSA. This study was designed to determine the effects of 40 mg of MS-Contin on tactile sensation, respiratory load detection, and respiratory magnitude perception in people with OSA during wakefulness. A double-blind, randomized, crossover design (1 wk washout) was used. Twenty-one men with untreated OSA (apnea/hypopnea index = 26 ± 17 events/h) recruited from a larger clinical study completed the protocol. Tactile sensation using von Frey filaments on the back of the hand, internal mucosa of the cheek, uvula, and posterior pharyngeal wall were not different between placebo and morphine [e.g., median (interquartile range) posterior wall = 0.16 (0.16, 0.4) vs. 0.4 (0.14, 1.8) g, P = 0.261]. Similarly, compared with placebo, morphine did not alter respiratory load detection thresholds for nadir mask pressure detected = −2.05 (−3.37, −1.55) vs. −2.19 (−3.36, −1.41) cmH2O, P = 0.767], or respiratory load magnitude perception [mean ± SD Borg scores during a 5 resistive load (range: 5–126 cmH2O·l−1·s−1) protocol = 4.5 ± 1.6 vs. 4.2 ± 1.2, P = 0.347] but did reduce minute ventilation during quiet breathing (11.4 ± 3.3 vs. 10.7 ± 2.6 l/min, P < 0.01). These findings indicate that 40 mg of MS-Contin does not systematically impair tactile or respiratory sensation in men with mild to moderate, untreated OSA. This suggests that altered respiratory sensation to acute mechanical stimuli is not likely to be a mechanism that contributes to worsening of OSA with a moderate dose of morphine.NEW & NOTEWORTHY Forty milligrams of MS-Contin does not alter upper airway tactile sensation, respiratory load detection thresholds, or respiratory load magnitude perception in people with obstructive sleep apnea but does decrease breathing compared with placebo during wakefulness. Despite increasing concerns of harm with opioids, the current findings suggest that impaired respiratory sensation to acute mechanical stimuli with this dose of MS-Contin is unlikely to be a direct mechanism contributing to worsening sleep apnea severity in people with mild-to-moderate disease.
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Affiliation(s)
- Rodrigo Tomazini Martins
- Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Faculty of Medicine, Sydney, New South Wales, Australia
| | - Jayne C. Carberry
- Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Faculty of Medicine, Sydney, New South Wales, Australia
| | - Simon C. Gandevia
- Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
- Prince of Wales Clinical School, University of New South Wales, Sydney, New South Wales, Australia
| | - Jane E. Butler
- Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Faculty of Medicine, Sydney, New South Wales, Australia
| | - Danny J. Eckert
- Neuroscience Research Australia (NeuRA), Randwick, New South Wales, Australia
- School of Medical Sciences, University of New South Wales, Faculty of Medicine, Sydney, New South Wales, Australia
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Severino AL, Shadfar A, Hakimian JK, Crane O, Singh G, Heinzerling K, Walwyn WM. Pain Therapy Guided by Purpose and Perspective in Light of the Opioid Epidemic. Front Psychiatry 2018; 9:119. [PMID: 29740351 PMCID: PMC5925443 DOI: 10.3389/fpsyt.2018.00119] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 03/21/2018] [Indexed: 12/12/2022] Open
Abstract
Prescription opioid misuse is an ongoing and escalating epidemic. Although these pharmacological agents are highly effective analgesics prescribed for different types of pain, opioids also induce euphoria, leading to increasing diversion and misuse. Opioid use and related mortalities have developed in spite of initial claims that OxyContin, one of the first opioids prescribed in the USA, was not addictive in the presence of pain. These claims allayed the fears of clinicians and contributed to an increase in the number of prescriptions, quantity of drugs manufactured, and the unforeseen diversion of these drugs for non-medical uses. Understanding the history of opioid drug development, the widespread marketing campaign for opioids, the immense financial incentive behind the treatment of pain, and vulnerable socioeconomic and physical demographics for opioid misuse give perspective on the current epidemic as an American-born problem that has expanded to global significance. In light of the current worldwide opioid epidemic, it is imperative that novel opioids are developed to treat pain without inducing the euphoria that fosters physical dependence and addiction. We describe insights from preclinical findings on the properties of opioid drugs that offer insights into improving abuse-deterrent formulations. One finding is that the ability of some agonists to activate one pathway over another, or agonist bias, can predict whether several novel opioid compounds bear promise in treating pain without causing reward among other off-target effects. In addition, we outline how the pharmacokinetic profile of each opioid contributes to their potential for misuse and discuss the emergence of mixed agonists as a promising pipeline of opioid-based analgesics. These insights from preclinical findings can be used to more effectively identify opioids that treat pain without causing physical dependence and subsequent opioid abuse.
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Affiliation(s)
- Amie L. Severino
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, United States
- Vatche and Tamar Manoukian Division of Digestive Diseases, Department of Medicine, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, United States
- Veteran Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, United States
- UCLA Brain Research Institute, Los Angeles, Los Angeles, CA, United States
| | - Arash Shadfar
- Department of Psychiatry, Western University of Health Sciences, Pomona, CA, United States
| | - Joshua K. Hakimian
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, United States
- UCLA Brain Research Institute, Los Angeles, Los Angeles, CA, United States
| | - Oliver Crane
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, United States
- UCLA Brain Research Institute, Los Angeles, Los Angeles, CA, United States
| | - Ganeev Singh
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, United States
- UCLA Brain Research Institute, Los Angeles, Los Angeles, CA, United States
| | - Keith Heinzerling
- Department of Family Medicine, David Geffen School of Medicine at the University of California, Los Angeles, CA, United States
| | - Wendy M. Walwyn
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, United States
- UCLA Brain Research Institute, Los Angeles, Los Angeles, CA, United States
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Hayes JA, Kottick A, Picardo MCD, Halleran AD, Smith RD, Smith GD, Saha MS, Del Negro CA. Transcriptome of neonatal preBötzinger complex neurones in Dbx1 reporter mice. Sci Rep 2017; 7:8669. [PMID: 28819234 PMCID: PMC5561182 DOI: 10.1038/s41598-017-09418-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 07/24/2017] [Indexed: 12/14/2022] Open
Abstract
We sequenced the transcriptome of brainstem interneurons in the specialized respiratory rhythmogenic site dubbed preBötzinger Complex (preBötC) from newborn mice. To distinguish molecular characteristics of the core oscillator we compared preBötC neurons derived from Dbx1-expressing progenitors that are respiratory rhythmogenic to neighbouring non-Dbx1-derived neurons, which support other respiratory and non-respiratory functions. Results in three categories are particularly salient. First, Dbx1 preBötC neurons express κ-opioid receptors in addition to μ-opioid receptors that heretofore have been associated with opiate respiratory depression, which may have clinical applications. Second, Dbx1 preBötC neurons express the hypoxia-inducible transcription factor Hif1a at levels three-times higher than non-Dbx1 neurons, which links core rhythmogenic microcircuits to O2-related chemosensation for the first time. Third, we detected a suite of transcription factors including Hoxa4 whose expression pattern may define the rostral preBötC border, Pbx3 that may influence ipsilateral connectivity, and Pax8 that may pertain to a ventrally-derived subset of Dbx1 preBötC neurons. These data establish the transcriptomic signature of the core respiratory oscillator at a perinatal stage of development.
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Affiliation(s)
- John A Hayes
- Department of Applied Science, Integrated Science Center, 540 Landrum Dr., The College of William and Mary, Williamsburg, VA, 23185, USA
| | - Andrew Kottick
- Department of Applied Science, Integrated Science Center, 540 Landrum Dr., The College of William and Mary, Williamsburg, VA, 23185, USA
| | - Maria Cristina D Picardo
- Department of Applied Science, Integrated Science Center, 540 Landrum Dr., The College of William and Mary, Williamsburg, VA, 23185, USA
| | - Andrew D Halleran
- Department of Biology, Integrated Science Center, 540 Landrum Dr., The College of William and Mary, Williamsburg, VA, 23185, USA
| | - Ronald D Smith
- Department of Applied Science, Integrated Science Center, 540 Landrum Dr., The College of William and Mary, Williamsburg, VA, 23185, USA
| | - Gregory D Smith
- Department of Applied Science, Integrated Science Center, 540 Landrum Dr., The College of William and Mary, Williamsburg, VA, 23185, USA
| | - Margaret S Saha
- Department of Biology, Integrated Science Center, 540 Landrum Dr., The College of William and Mary, Williamsburg, VA, 23185, USA
| | - Christopher A Del Negro
- Department of Applied Science, Integrated Science Center, 540 Landrum Dr., The College of William and Mary, Williamsburg, VA, 23185, USA.
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Poliacek I, Simera M, Veternik M, Kotmanova Z, Bolser DC, Machac P, Jakus J. Role of the dorsomedial medulla in suppression of cough by codeine in cats. Respir Physiol Neurobiol 2017; 246:59-66. [PMID: 28778649 DOI: 10.1016/j.resp.2017.07.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 07/23/2017] [Accepted: 07/28/2017] [Indexed: 12/24/2022]
Abstract
The modulation of cough by microinjections of codeine in 3 medullary regions, the solitary tract nucleus rostral to the obex (rNTS), caudal to the obex (cNTS) and the lateral tegmental field (FTL) was studied. Experiments were performed on 27 anesthetized spontaneously breathing cats. Electromyograms (EMG) were recorded from the sternal diaphragm and expiratory muscles (transversus abdominis and/or obliquus externus; ABD). Repetitive coughing was elicited by mechanical stimulation of the intrathoracic airways. Bilateral microinjections of codeine (3.3 or 33mM, 54±16nl per injection) in the cNTS had no effect on cough, while those in the rNTS and in the FTL reduced coughing. Bilateral microinjections into the rNTS (3.3mM codeine, 34±1 nl per injection) reduced the number of cough responses by 24% (P<0.05), amplitudes of diaphragm EMG by 19% (P<0.01), of ABD EMG by 49% (P<0.001) and of expiratory esophageal pressure by 56% (P<0.001). Bilateral microinjections into the FTL (33mM codeine, 33±3 nl per injection) induced reductions in cough expiratory as well as inspiratory EMG amplitudes (ABD by 60% and diaphragm by 34%; P<0.01) and esophageal pressure amplitudes (expiratory by 55% and inspiratory by 26%; P<0.001 and 0.01, respectively). Microinjections of vehicle did not significantly alter coughing. Breathing was not affected by microinjections of codeine. These results suggest that: 1) codeine acts within the rNTS and the FTL to reduce cough in the cat, 2) the neuronal circuits in these target areas have unequal sensitivity to codeine and/or they have differential effects on spatiotemporal control of cough, 3) the cNTS has a limited role in the cough suppression induced by codeine in cats.
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Affiliation(s)
- Ivan Poliacek
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Institute of Medical Biophysics, Mala Hora 4, 036 01, Martin, Slovakia
| | - Michal Simera
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Institute of Medical Biophysics, Mala Hora 4, 036 01, Martin, Slovakia.
| | - Marcel Veternik
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Institute of Medical Biophysics, Mala Hora 4, 036 01, Martin, Slovakia
| | - Zuzana Kotmanova
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Institute of Medical Biophysics, Mala Hora 4, 036 01, Martin, Slovakia
| | - Donald C Bolser
- Dept. of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA
| | - Peter Machac
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Institute of Medical Biophysics, Mala Hora 4, 036 01, Martin, Slovakia
| | - Jan Jakus
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Institute of Medical Biophysics, Mala Hora 4, 036 01, Martin, Slovakia
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Langer TM, Neumueller SE, Crumley E, Burgraff NJ, Talwar S, Hodges MR, Pan L, Forster HV. Effects on breathing of agonists to μ-opioid or GABA A receptors dialyzed into the ventral respiratory column of awake and sleeping goats. Respir Physiol Neurobiol 2017; 239:10-25. [PMID: 28137700 PMCID: PMC5996971 DOI: 10.1016/j.resp.2017.01.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 01/09/2017] [Accepted: 01/12/2017] [Indexed: 01/01/2023]
Abstract
Pulmonary ventilation (V̇I) in awake and sleeping goats does not change when antagonists to several excitatory G protein-coupled receptors are dialyzed unilaterally into the ventral respiratory column (VRC). Concomitant changes in excitatory neuromodulators in the effluent mock cerebral spinal fluid (mCSF) suggest neuromodulatory compensation. Herein, we studied neuromodulatory compensation during dialysis of agonists to inhibitory G protein-coupled or ionotropic receptors into the VRC. Microtubules were implanted into the VRC of goats for dialysis of mCSF mixed with agonists to either μ-opioid (DAMGO) or GABAA (muscimol) receptors. We found: (1) V̇I decreased during unilateral but increased during bilateral dialysis of DAMGO, (2) dialyses of DAMGO destabilized breathing, (3) unilateral dialysis of muscimol increased V̇I, and (4) dialysis of DAMGO decreased GABA in the effluent mCSF. We conclude: (1) neuromodulatory compensation can occur during altered inhibitory neuromodulator receptor activity, and (2) the mechanism of compensation differs between G protein-coupled excitatory and inhibitory receptors and between G protein-coupled and inotropic inhibitory receptors.
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Affiliation(s)
- Thomas M Langer
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States
| | - Suzanne E Neumueller
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States
| | - Emma Crumley
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States
| | - Nicholas J Burgraff
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States
| | - Sawan Talwar
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States
| | - Matthew R Hodges
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States; Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI 53226, United States
| | - Lawrence Pan
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States; Department of Physical Therapy, Marquette University, Milwaukee, WI 53226, United States
| | - Hubert V Forster
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, United States; Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI 53226, United States; Zablocki Veterans Affairs Medical Center, Milwaukee, WI 53226, United States.
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Lalley PM, Mifflin SW. Oscillation patterns are enhanced and firing threshold is lowered in medullary respiratory neuron discharges by threshold doses of a μ-opioid receptor agonist. Am J Physiol Regul Integr Comp Physiol 2017; 312:R727-R738. [PMID: 28202437 DOI: 10.1152/ajpregu.00120.2016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Revised: 01/17/2017] [Accepted: 02/06/2017] [Indexed: 11/22/2022]
Abstract
μ-Opioid receptors are distributed widely in the brain stem respiratory network, and opioids with selectivity for μ-type receptors slow in vivo respiratory rhythm in lowest effective doses. Several studies have reported μ-opioid receptor effects on the three-phase rhythm of respiratory neurons, but there are until now no reports of opioid effects on oscillatory activity within respiratory discharges. In this study, effects of the μ-opioid receptor agonist fentanyl on spike train discharge properties of several different types of rhythm-modulating medullary respiratory neuron discharges were analyzed. Doses of fentanyl that were just sufficient for prolongation of discharges and slowing of the three-phase respiratory rhythm also produced pronounced enhancement of spike train properties. Oscillation and burst patterns detected by autocorrelation measurements were greatly enhanced, and interspike intervals were prolonged. Spike train properties under control conditions and after fentanyl were uniform within each experiment, but varied considerably between experiments, which might be related to variability in acid-base balance in the brain stem extracellular fluid. Discharge threshold was shifted to more negative levels of membrane potential. The effects on threshold are postulated to result from opioid-mediated disinhibition and postsynaptic enhancement of N-methyl-d- aspartate receptor current. Lowering of firing threshold, enhancement of spike train oscillations and bursts and prolongation of discharges by lowest effective doses of fentanyl could represent compensatory adjustments in the brain stem respiratory network to override opioid blunting of CO2/pH chemosensitivity.
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Affiliation(s)
- Peter M Lalley
- Department of Neuroscience, University of Wisconsin Medical Sciences Center, Madison, Wisconsin; and
| | - Steve W Mifflin
- Institute for Cardiovascular and Metabolic Disease, University of North Texas Health Science Center, Fort Worth, Texas
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Ventilation and the Response to Hypercapnia after Morphine in Opioid-naive and Opioid-tolerant Rats. Anesthesiology 2016; 124:945-57. [PMID: 26734964 DOI: 10.1097/aln.0000000000000997] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Opioid-related deaths are a leading cause of accidental death, with most occurring in patients receiving chronic pain therapy. Respiratory arrest is the usual cause of death, but mechanisms increasing that risk with increased length of treatment remain unclear. Repeated administration produces tolerance to opioid analgesia, prompting increased dosing, but depression of ventilation may not gain tolerance to the same degree. This study addresses differences in the degree to which chronic morphine (1) produces tolerance to ventilatory depression versus analgesia and (2) alters the magnitude and time course of ventilatory depression. METHODS Juvenile rats received subcutaneous morphine for 3 days (n = 116) or vehicle control (n = 119) and were then tested on day 4 following one of a range of morphine doses for (a) analgesia by paw withdraw from heat or (b) respiratory parameters by plethysmography-respirometry. RESULTS Rats receiving chronic morphine showed significant tolerance to morphine sedation and analgesia (five times increased ED50). When sedation was achieved for all animals in a dose group (lowest effective doses: opioid-tolerant, 15 mg/kg; opioid-naive, 3 mg/kg), the opioid-tolerant showed similar magnitudes of depressed ventilation (-41.4 ± 7.0%, mean ± SD) and hypercapnic response (-80.9 ± 15.7%) as found for morphine-naive (-35.5 ± 16.9% and -67.7 ± 15.1%, respectively). Ventilation recovered due to tidal volume without recovery of respiratory rate or hypercapnic sensitivity and more slowly in morphine-tolerant. CONCLUSIONS In rats, gaining tolerance to morphine analgesia does not reduce ventilatory depression effects when sedated and may inhibit recovery of ventilation.
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Vozoris NT, Wang X, Fischer HD, Bell CM, O'Donnell DE, Austin PC, Stephenson AL, Gill SS, Rochon PA. Incident opioid drug use and adverse respiratory outcomes among older adults with COPD. Eur Respir J 2016; 48:683-93. [DOI: 10.1183/13993003.01967-2015] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 05/16/2016] [Indexed: 11/05/2022]
Abstract
We evaluated risk of adverse respiratory outcomes associated with incident opioid use among older adults with chronic obstructive pulmonary diseases (COPD).This was a retrospective population-based cohort study using a validated algorithm applied to health administrative data to identify adults aged 66 years and older with COPD. Inverse probability of treatment weighting using the propensity score was used to estimate hazard ratios comparing adverse respiratory outcomes within 30 days of incident opioid use compared to controls.Incident opioid use was associated with significantly increased emergency room visits for COPD or pneumonia (HR 1.14, 95% CI 1.00–1.29; p=0.04), COPD or pneumonia-related mortality (HR 2.16, 95% CI 1.61–2.88; p<0.0001) and all-cause mortality (HR 1.76, 95% CI 1.57–1.98; p<0.0001), but significantly decreased outpatient exacerbations (HR 0.88, 95% CI 0.83–0.94; p=0.0002). Use of more potent opioid-only agents was associated with significantly increased outpatient exacerbations, emergency room visits and hospitalisations for COPD or pneumonia, and COPD or pneumonia-related and all-cause mortality.Incident opioid use, and in particular use of the generally more potent opioid-only agents, was associated with increased risk for adverse respiratory outcomes, including respiratory-related mortality, among older adults with COPD. Potential adverse respiratory outcomes should be considered when prescribing new opioids in this population.
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Haji A, Kimura S, Ohi Y. Reversal of morphine-induced respiratory depression by doxapram in anesthetized rats. Eur J Pharmacol 2016; 780:209-15. [DOI: 10.1016/j.ejphar.2016.03.053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 03/23/2016] [Accepted: 03/29/2016] [Indexed: 10/22/2022]
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Shin CH, Zaremba S, Devine S, Nikolov M, Kurth T, Eikermann M. Effects of obstructive sleep apnoea risk on postoperative respiratory complications: protocol for a hospital-based registry study. BMJ Open 2016; 6:e008436. [PMID: 26769778 PMCID: PMC4735131 DOI: 10.1136/bmjopen-2015-008436] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
INTRODUCTION Obstructive sleep apnoea (OSA), the most common type of sleep-disordered breathing, is associated with significant immediate and long-term morbidity, including fragmented sleep and impaired daytime functioning, as well as more severe consequences, such as hypertension, impaired cognitive function and reduced quality of life. Perioperatively, OSA occurs frequently as a consequence of pre-existing vulnerability, surgery and drug effects. The impact of OSA on postoperative respiratory complications (PRCs) needs to be better characterised. As OSA is associated with significant comorbidities, such as obesity, pulmonary hypertension, myocardial infarction and stroke, it is unclear whether OSA or its comorbidities are the mechanism of PRCs. This project aims to (1) develop a novel prediction score identifying surgical patients at high risk of OSA, (2) evaluate the association of OSA risk on PRCs and (3) evaluate if pharmacological agents used during surgery modify this association. METHODS Retrospective cohort study using hospital-based electronic patient data and perioperative data on medications administered and vital signs. We will use data from Partners Healthcare clinical databases, Boston, Massachusetts. First, a prediction model for OSA will be developed using OSA diagnostic codes and polysomnography procedural codes as the reference standard, and will be validated by medical record review. Results of the prediction model will be used to classify patients in the database as high, medium or low risk of OSA, and we will investigate the effect of OSA on risk of PRCs. Finally, we will test whether the effect of OSA on PRCs is modified by the use of intraoperative pharmacological agents known to increase upper airway instability, including neuromuscular blockade, neostigmine, opioids, anaesthetics and sedatives. ETHICS AND DISSEMINATION The Partners Human Research Committee approved this study (protocol number: 2014P000218). Study results will be made available in the form of manuscripts for publication and presentations at national and international meetings.
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Affiliation(s)
- Christina H Shin
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Sebastian Zaremba
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Department of Sleep Medicine, Department of Neurology, University Hospital Bonn, Rheinische Friedrich-Wilhelms-University, Bonn, Germany
| | - Scott Devine
- Center for Observational and Real-World Effectiveness US Outcomes Research, Merck & Co., Inc, Boston, Massachusetts, USA
| | - Milcho Nikolov
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Tobias Kurth
- Harvard Medical School, Boston, Massachusetts, USA
- Institute of Public Health, Charite Universitatsmedizin, Berlin, Germany
| | - Matthias Eikermann
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Boston, Massachusetts, USA
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Abstract
Depending on the subpopulation, obstructive sleep apnea (OSA) can affect more than 75% of surgical patients. An increasing body of evidence supports the association between OSA and perioperative complications, but some data indicate important perioperative outcomes do not differ between patients with and without OSA. In this review we will provide an overview of the pathophysiology of sleep apnea and the risk factors for perioperative complications related to sleep apnea. We also discuss a clinical algorithm for the identification and management of OSA patients facing surgery.
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Affiliation(s)
- Sebastian Zaremba
- Department of Anaesthesia Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114, USA; Department of Neurology, Rheinische-Friedrich-Wilhelms-University, Bonn, D-53127, Germany; German Center for Neurodegenerative Diseases, Bonn, D-53127, Germany
| | - James E Mojica
- Department of Pulmonary and Critical Care Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114, USA
| | - Matthias Eikermann
- Department of Anaesthesia Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, 02114, USA; Department of Anaesthesia and Critical Care, University Hospital Essen, Essen, 45147, Germany
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Inhibitory Effect of Endomorphin-2 Binding to the μ-Opioid Receptor in the Rat Pre-Bötzinger Complex on the Breathing Activity. Mol Neurobiol 2016; 54:461-469. [DOI: 10.1007/s12035-015-9624-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 12/08/2015] [Indexed: 12/13/2022]
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Vozoris NT, Wang X, Fischer HD, Gershon AS, Bell CM, Gill SS, O'Donnell DE, Austin PC, Stephenson AL, Rochon PA. Incident opioid drug use among older adults with chronic obstructive pulmonary disease: a population-based cohort study. Br J Clin Pharmacol 2015; 81:161-70. [PMID: 26337922 DOI: 10.1111/bcp.12762] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/05/2015] [Accepted: 08/20/2015] [Indexed: 01/06/2023] Open
Abstract
AIMS The purpose of the present study was to describe the scope, pattern and patient characteristics associated with incident opioid use among older adults with chronic obstructive pulmonary disease (COPD). METHODS This was a retrospective population-based cohort study using Ontario, Canada, healthcare administrative data. Study participants were individuals aged 66 years and older with physician-diagnosed COPD, identified using a validated algorithm, who were not receiving palliative care. We examined the incidence of oral opioid receipt between 1 April 2003 and 31 March 2012, as well as several patterns of incident opioid drug use. RESULTS Among 107,109 community-dwelling and 16,207 long-term care resident older adults with COPD, 72,962 (68.1%) and 8811 (54.4%), respectively, received an incident opioid drug during the observation period. Among long-term care residents, multiple opioid dispensings (8.8%), dispensings for >30 days' duration (up to 19.8%), second dispensings (35-43%) and early refills (24.2%) were observed. Incident opioid dispensing was also observed to occur during COPD exacerbations (6.9% among all long-term care residents; 18.1% among long-term care residents with frequent exacerbations). These same patterns of incident opioid use occurred among community-dwelling individuals, but with relatively lower frequencies. CONCLUSIONS New opioid use was high among older adults with COPD. Potential safety concerns are raised by the degree and pattern of new opioid use, but further studies are needed to evaluate if adverse events are associated with opioid drug use in this older and respiratory-vulnerable population.
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Affiliation(s)
- Nicholas T Vozoris
- Division of Respirology, Department of Medicine, St Michael's Hospital, Toronto, Ontario, Canada.,Keenan Research Centre in the Li Ka Shing Knowledge Institute, St Michael's Hospital, Toronto, Ontario, Canada.,Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Xuesong Wang
- Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada
| | - Hadas D Fischer
- Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada
| | - Andrea S Gershon
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.,Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada.,Division of Respirology, Department of Medicine, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - Chaim M Bell
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.,Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada.,Division of General Internal Medicine, Department of Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Sudeep S Gill
- Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.,Department of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Denis E O'Donnell
- Department of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Peter C Austin
- Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.,Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
| | - Anne L Stephenson
- Division of Respirology, Department of Medicine, St Michael's Hospital, Toronto, Ontario, Canada.,Keenan Research Centre in the Li Ka Shing Knowledge Institute, St Michael's Hospital, Toronto, Ontario, Canada.,Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
| | - Paula A Rochon
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.,Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada.,Women's College Research Institute, Women's College Hospital, Toronto, Ontario, Canada
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Campagna I, Schwarz A, Keller S, Bettschart-Wolfensberger R, Mosing M. Comparison of the effects of propofol or alfaxalone for anaesthesia induction and maintenance on respiration in cats. Vet Anaesth Analg 2015; 42:484-92. [DOI: 10.1111/vaa.12231] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Accepted: 06/24/2014] [Indexed: 12/01/2022]
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Correa D, Farney RJ, Chung F, Prasad A, Lam D, Wong J. Chronic Opioid Use and Central Sleep Apnea. Anesth Analg 2015; 120:1273-85. [DOI: 10.1213/ane.0000000000000672] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Montandon G, Horner R. CrossTalk proposal: The preBotzinger complex is essential for the respiratory depression following systemic administration of opioid analgesics. J Physiol 2015; 592:1159-62. [PMID: 24634011 DOI: 10.1113/jphysiol.2013.261974] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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49
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Lalley PM, Pilowsky PM, Forster HV, Zuperku EJ. CrossTalk opposing view: The pre-Botzinger complex is not essential for respiratory depression following systemic administration of opioid analgesics. J Physiol 2015; 592:1163-6. [PMID: 24634012 DOI: 10.1113/jphysiol.2013.258830] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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Selective mu and kappa Opioid Agonists Inhibit Voltage-Gated Ca2+ Entry in Isolated Neonatal Rat Carotid Body Type I Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 860:49-54. [PMID: 26303466 DOI: 10.1007/978-3-319-18440-1_6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
It is known that opioids inhibit the hypoxic ventilatory response in part via an action at the carotid body, but little is known about the cellular mechanisms that underpin this. This study's objectives were to examine which opioid receptors are located on the oxygen-sensing carotid body type I cells from the rat and determine the mechanism by which opioids might inhibit cellular excitability.Immunocytochemistry revealed the presence of μ and κ opioid receptors on type I cells. The μ-selective agonist DAMGO (10 μM) and the κ-selective agonist U50-488 (10 μM) inhibited high K(+) induced rises in intracellular Ca(2+) compared with controls. After 3 h incubation (37 °C) with pertussis toxin (150 ng ml(-1)), DAMGO (10 μM) and U50-488 (10 μM) had no significant effect on the Ca(2+) response to high K(+).These results indicate that opioids acting at μ and κ receptors inhibit voltage-gated Ca(2+) influx in rat carotid body type I cells via G(i)-coupled mechanisms. This mechanism may contribute to opioid's inhibitory actions in the carotid body.
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