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Hunt MA, Hunt SAC, Edinger K, Steinauer J, Yaksh TL. Refinement of intrathecal catheter design to enhance neuraxial distribution. J Neurosci Methods 2024; 402:110006. [PMID: 37967672 DOI: 10.1016/j.jneumeth.2023.110006] [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: 04/07/2023] [Revised: 10/11/2023] [Accepted: 11/09/2023] [Indexed: 11/17/2023]
Abstract
BACKGROUND Delivery of therapeutics via indwelling intrathecal catheters is highly efficacious for targeting of pain, spasticity, neuraxial cancer and neurodegenerative disorders. However, current catheter designs have some major limitations. Given limited CSF flow, fixed intrathecal volume and the large distance of the rostro-caudal spinal axis, current intrathecal delivery routes fail to achieve adequate drug distribution. Additionally open catheter systems are plagued with cellular ingrowth and debris accumulation if used intermittently. NEW METHOD RESULTS/COMPARISON WITH EXISTING METHOD(S): High speed imaging showed micro-valve catheters greatly increase fluid exit velocities compared to typical open-ended catheters, which prevents pooling of injectate proximal to the opening. When implanted intrathecally in rats, small injection volumes (7.5 μL) of dye or AAV9-RFP, resulted in an even rostro-caudal distribution along the spinal axis and robust transfection of neurons from cervical to lumbar dorsal root ganglia. In contrast, such injections with an open-ended catheter resulted in localized distribution and transfection proximal to the delivery site. Our poly micro-valve catheter design resulted in equivalent transfection rates of cervical DRG neurons using 100x lower titer of AAV9-RFP. Unlike open port catheters, no debris accumulation was observed in the lumen of implanted catheters, showing potential for long-term intermittent use. CONCLUSIONS This catheter platform, suitable for small animal models is easily scalable for human use and addresses many of the problems observed with common catheter systems.
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Affiliation(s)
- Matthew A Hunt
- Departments of Anesthesiology and Pharmacology, University of California, San Diego, 9500, Gilman Drive, La Jolla, CA 92093, United States; Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Sara A C Hunt
- Departments of Anesthesiology and Pharmacology, University of California, San Diego, 9500, Gilman Drive, La Jolla, CA 92093, United States; Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Kelly Edinger
- Departments of Anesthesiology and Pharmacology, University of California, San Diego, 9500, Gilman Drive, La Jolla, CA 92093, United States; Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Joanne Steinauer
- Departments of Anesthesiology and Pharmacology, University of California, San Diego, 9500, Gilman Drive, La Jolla, CA 92093, United States; Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Tony L Yaksh
- Departments of Anesthesiology and Pharmacology, University of California, San Diego, 9500, Gilman Drive, La Jolla, CA 92093, United States; Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States.
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Kassim DY, Mahmoud HE, Fakhry DM, Mansour MA. Comparative study of dexmedetomidine versus fentanyl as adjuvants to bupivacaine in ultrasound-guided transversus abdominis plane block in patients undergoing radical cystectomy: a prospective randomised study. BMC Anesthesiol 2022; 22:340. [PMID: 36344917 PMCID: PMC9639282 DOI: 10.1186/s12871-022-01877-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 10/19/2022] [Indexed: 11/09/2022] Open
Abstract
Background Transversus abdominis plane (TAP) block is beneficial for pain management after conducting abdominal surgery. Objective To compare the outcomes of dexmedetomidine and fentanyl, as adjuvants to bupivacaine, for ultrasound-guided TAP block analgesia among patients undergoing radical cystectomy for postoperative pain management. Methods This prospective, randomised, comparative study included a total of 60 patients, who underwent radical cystectomy. Participants were randomly divided into three categories with 20 subjects each; group B had patients who received a single shot US-guided TAP block on each side with 20 ml of 0.25% bupivacaine + 2 ml normal saline; group BF had patients who received a single shot US-guided TAP block on each side with 20 ml of 0.25% bupivacaine + 1 µg/kg fentanyl dissolved in 2 ml normal saline and group BD had patients who received a single shot US-guided TAP block on each side with 20 ml of 0.25% bupivacaine + 1 µg/kg dexmedetomidine dissolved in 2 ml normal saline.The researchers recorded the time taken for first rescue analgesia, total analgesic dose in the first 24 h after surgery, patient satisfaction, sedation score, and postoperative complications. Results The time taken for first rescue analgesia was significantly lengthier in group (BD) (8.90 ± 2.47) than (BF) (6.50 ± 1.43) and (B) (4.40 ± 1.05) groups. The total nalbuphine consumption, during the first 24 h, was significantly lower in (BD) (0.15 ± 0.00) group compared to (BF) (0.20 ± 0.07) and (B) (0.24 ± 0.08) groups. Conclusion In comparison with fentanyl, as an adjuvant to bupivacaine, dexmedetomidine was found to be associated with prolonged postoperative analgesia, less postoperative pain scores and low opioid consumption. Trial registration This study was registered at Clinical Trials.gov on 23 March 2020 (registration number: NCT04318158).
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Chanbour H, Zuckerman SL. Commentary: Intrathecal Fentanyl With a Myofascial Plane Block in Open Lumbar Surgeries: A Case Series. Oper Neurosurg (Hagerstown) 2022; 22:e241-e242. [DOI: 10.1227/ons.0000000000000195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 11/19/2022] Open
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Krishna Prasad GV, Khanna S, Jaishree SV. Review of adjuvants to local anesthetics in peripheral nerve blocks: Current and future trends. Saudi J Anaesth 2020; 14:77-84. [PMID: 31998024 PMCID: PMC6970354 DOI: 10.4103/sja.sja_423_19] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Accepted: 07/21/2019] [Indexed: 02/07/2023] Open
Abstract
In recent anesthetic practice, peripheral nerve blocks (PNBs) are used extensively for surgical anesthesia and nonsurgical analgesia. PNBs offer many benefits over other anesthetic techniques in a certain population of patients, and in some specific clinical setting, that may contribute to faster and safer pain relief, increased patient satisfaction, reduced hospital stay, and decreased overall healthcare cost. The technique involves the injection of the anesthetic in the vicinity of a specific nerve or bundle of nerves to block the sensation of pain transmitting to a specific portion of the body. However, the length of analgesia when a single anesthetic is used for PNB may not last long. Therefore, the practice of adding an additional agent called adjuvant has been evolved to prolong the analgesic effect. There are many such adjuvants available that are clinically being used for this purpose imparting great efficacy and safety to the anesthetic process. The adjuvants molecules are generally classified as opioids, alpha-2 agonist, steroids, etc. Most of them are safe to use and show little or no adverse event related to neurotoxicity and tissue damage. Although there is extensive use of such adjuvants in the clinical field, none of the molecules is approved by the FDA and is used as an off-label drug. The risk to benefit ratio must be assessed while using such an agent. This review will try to delineate the basic need of adjuvant in peripheral nerve block and will discuss the advantages and limitations of using different adjuvants and will discuss the future prospect of such application.
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Affiliation(s)
- G V Krishna Prasad
- Department of Anaesthesiology, Military Hospital, Kirkee, Range Hills, Pune, Maharashtra, India
| | - Sangeeta Khanna
- Department of Anaesthesiology, Military Hospital, Kirkee, Range Hills, Pune, Maharashtra, India
| | - Sharma Vipin Jaishree
- Department of Anaesthesiology, Military Hospital, Kirkee, Range Hills, Pune, Maharashtra, India
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Hildebrand KR, Page LM, Billstrom TM, Steinauer JJ, Eddinger KA, Arjomand S, Yaksh TL. Characterization of Effect of Repeated Bolus or Continuous Intrathecal Infusion of Morphine on Spinal Mass Formation in the Dog. Neuromodulation 2019; 22:790-798. [PMID: 31124198 DOI: 10.1111/ner.12963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Revised: 02/22/2019] [Accepted: 03/21/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND We determined whether intrathecally delivering the same daily dose of morphine (MS) at a fixed concentration of 25 mg/mL by periodic boluses versus continuous infusion would reduce intrathecal mass (IMs) formation in dogs. METHODS Adult dogs (hound cross, n = 32) were implanted with intrathecal catheters connected to SynchroMed II infusion pumps. Animals were randomly assigned to receive infusion of 0.48 mL/day of saline or MS dosing (12 mg/day at 25 mg/mL) as boluses: x1 (q24hour), x2 (q12hour), x4 (q6hour), or x8 (q3hour) given at the rate of 1000 μL/hour, or as a continuous infusion (25 mg/mL/20 μL/hour). RESULTS With IT saline, minimal pathology was noted. In contrast, animals receiving morphine displayed spinally compressing durally derived masses with the maximal cross-sectional area being greatest near the catheter tip. Histopathology showed that IMs consisted of fibroblasts in a collagen (type 1) matrix comprised of newly formed collagen near the catheter and mature collagen on the periphery of the mass. The rank order of median cross-sectional mass area (mm2 ) was: Saline: 0.7 mm2 ; x2: 1.8 mm2 ; x4: 2.7 mm2 ; x1: 2.7 mm2 ; x8: 4.2 mm2 ; Continuous: 8.1 mm2 , with statistical difference from saline being seen with continuous (p < 0.0001) and x8 (p < 0.05). Bench studies with a 2D diffusion chamber confirmed an increase in dye distribution and lower peak concentrations after bolus delivery versus continuous infusion of dye. CONCLUSIONS Using multiple bolus dosing, IMs were reduced as compared to continuous infusion, suggesting relevance of bolus delivery in yielding reduced intrathecal masses.
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Affiliation(s)
- Keith R Hildebrand
- Medtronic, Restorative Therapies Group, Targeted Drug Delivery, Minneapolis, MN, USA
| | - Linda M Page
- Medtronic, Restorative Therapies Group, Targeted Drug Delivery, Minneapolis, MN, USA
| | - Tina M Billstrom
- Medtronic Physiological Research Laboratories, Coon Rapid, MN, USA
| | - Joanne J Steinauer
- Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - Kelly A Eddinger
- Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - Shervin Arjomand
- Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
| | - Tony L Yaksh
- Department of Anesthesiology, University of California, San Diego, La Jolla, CA, USA
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Mendonça FT, Lucena MCD, Quirino RS, Govêia CS, Guimarães GMN. Fatores de risco para hipotermia pós‐operatória em sala de recuperação pós‐anestésica: estudo piloto prospectivo de prognóstico. Braz J Anesthesiol 2019; 69:122-130. [DOI: 10.1016/j.bjan.2018.10.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 10/11/2018] [Accepted: 10/31/2018] [Indexed: 10/27/2022] Open
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Risk factors for postoperative hypothermia in the post-anesthetic care unit: a prospective prognostic pilot study. BRAZILIAN JOURNAL OF ANESTHESIOLOGY (ENGLISH EDITION) 2019. [PMID: 30685072 PMCID: PMC9391915 DOI: 10.1016/j.bjane.2018.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Background Design and setting Methods Results Conclusion
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Cerebrospinal Fluid Dynamics and Intrathecal Delivery. Neuromodulation 2018. [DOI: 10.1016/b978-0-12-805353-9.00067-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Tangen KM, Leval R, Mehta AI, Linninger AA. Computational and In Vitro Experimental Investigation of Intrathecal Drug Distribution: Parametric Study of the Effect of Injection Volume, Cerebrospinal Fluid Pulsatility, and Drug Uptake. Anesth Analg 2017; 124:1686-1696. [PMID: 28431428 DOI: 10.1213/ane.0000000000002011] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND Intrathecal drug delivery is an attractive option to circumvent the blood-brain barrier for pain management through its increased efficacy of pain relief, reduction in adverse side effects, and cost-effectiveness. Unfortunately, there are limited guidelines for physicians to choose infusion or drug pump settings to administer therapeutic doses to specific regions of the spine or the brain. Although empiric trialing of intrathecal drugs is critical to determine the sustained side effects, currently there is no inexpensive in vitro method to guide the selection of spinal drug delivery parameters. The goal of this study is to demonstrate current computational capabilities to predict drug biodistribution while varying 3 parameters: (1) infusion settings, (2) drug chemistry, and (3) subject-specific anatomy and cerebrospinal fluid dynamics. We will discuss strategies to systematically optimize these 3 parameters to administer drug molecules to targeted tissue locations in the central nervous system. METHODS We acquired anatomical data from magnetic resonance imaging (MRI) and velocity measurements in the spinal cerebrospinal fluid with CINE-MRI for 2 subjects. A bench-top surrogate of the subject-specific central nervous system was constructed to match measured anatomical dimensions and volumes. We generated a computational mesh for the bench-top model. Idealized simulations of tracer distribution were compared with bench-top measurements for validation. Using reconstructions from MRI data, we also introduced a subject-specific computer model for predicting drug spread for the human volunteer. RESULTS MRI velocity measurements at 3 spinal regions of interest reasonably matched the simulated flow fields in a subject-specific computer mesh. Comparison between the idealized spine computations and bench-top tracer distribution experiments demonstrate agreement of our drug transport predictions to this physical model. Simulated multibolus drug infusion theoretically localizes drug to the cervical and thoracic region. Continuous drug pump and single bolus injection were successful to target the lumbar spine in the simulations. The parenchyma might be targeted suitably by multiple boluses followed by a flush infusion. We present potential guidelines that take into account drug specific kinetics for tissue uptake, which influence the speed of drug dispersion in the model and potentially influence tissue targeting. CONCLUSIONS We present potential guidelines considering drug-specific kinetics of tissue uptake, which determine the speed of drug dispersion and influence tissue targeting. However, there are limitations to this analysis in that the parameters were obtained from an idealized healthy patient in a supine position. The proposed methodology could assist physicians to select clinical infusion parameters for their patients and provide guidance to optimize treatment algorithms. In silico optimization of intrathecal drug delivery therapies presents the first steps toward a possible care paradigm in the future that is specific to personalized patient anatomy and diseases.
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Affiliation(s)
- Kevin M Tangen
- From the Departments of *Bioengineering; and †Neurosurgery, University of Illinois at Chicago, Chicago, Illinois
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Yaksh TL, Fisher CJ, Hockman TM, Wiese AJ. Current and Future Issues in the Development of Spinal Agents for the Management of Pain. Curr Neuropharmacol 2017; 15:232-259. [PMID: 26861470 PMCID: PMC5412694 DOI: 10.2174/1570159x14666160307145542] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Revised: 12/02/2015] [Accepted: 02/05/2016] [Indexed: 11/22/2022] Open
Abstract
Targeting analgesic drugs for spinal delivery reflects the fact that while the conscious experience of pain is mediated supraspinally, input initiated by high intensity stimuli, tissue injury and/or nerve injury is encoded at the level of the spinal dorsal horn and this output informs the brain as to the peripheral environment. This encoding process is subject to strong upregulation resulting in hyperesthetic states and downregulation reducing the ongoing processing of nociceptive stimuli reversing the hyperesthesia and pain processing. The present review addresses the biology of spinal nociceptive processing as relevant to the effects of intrathecally-delivered drugs in altering pain processing following acute stimulation, tissue inflammation/injury and nerve injury. The review covers i) the major classes of spinal agents currently employed as intrathecal analgesics (opioid agonists, alpha 2 agonists; sodium channel blockers; calcium channel blockers; NMDA blockers; GABA A/B agonists; COX inhibitors; ii) ongoing developments in the pharmacology of spinal therapeutics focusing on less studied agents/targets (cholinesterase inhibition; Adenosine agonists; iii) novel intrathecal targeting methodologies including gene-based approaches (viral vectors, plasmids, interfering RNAs); antisense, and toxins (botulinum toxins; resniferatoxin, substance P Saporin); and iv) issues relevant to intrathecal drug delivery (neuraxial drug distribution), infusate delivery profile, drug dosing, formulation and principals involved in the preclinical evaluation of intrathecal drug safety.
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Affiliation(s)
- Tony L. Yaksh
- University of California, San Diego, Anesthesia Research Lab 0818, 9500 Gilman Dr. LaJolla, CA 92093, USA
| | - Casey J. Fisher
- University of California, San Diego, Anesthesia Research Lab 0818, 9500 Gilman Dr. LaJolla, CA 92093, USA
| | - Tyler M. Hockman
- University of California, San Diego, Anesthesia Research Lab 0818, 9500 Gilman Dr. LaJolla, CA 92093, USA
| | - Ashley J. Wiese
- University of California, San Diego, Anesthesia Research Lab 0818, 9500 Gilman Dr. LaJolla, CA 92093, USA
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Abstract
Abstract
Background
Intrathecal infusion of opioids in dogs, sheep, and humans produces local space-occupying masses. To develop a small-animal model, the authors examined effects of intrathecal catheterization and morphine infusion in guinea pigs.
Methods
Under isoflurane, polyethylene or polyurethane catheters were advanced from the cisterna magna to the lumbar enlargement. Drugs were delivered as a bolus through the externalized catheter or continuously by subcutaneous minipumps. Hind paw withdrawal to a thermal stimulus was assessed. Spinal histopathology was systematically assessed in a blinded fashion. To assist in determining catheter placement, ex vivo images were obtained using magnetic resonance imaging in several animals. Canine spinal tissue from previous intrathecal morphine studies was analyzed in parallel.
Results
(1) Polyethylene (n = 30) and polyurethane (n = 25) catheters were implanted in the lumbar intrathecal space. (2) Bolus intrathecal morphine produced a dose-dependent (20 to 40 μg/10 μl) increase in thermal escape latencies. (3) Absent infusion, a catheter-associated distortion of the spinal cord and a fibrotic investment were noted along the catheter tract (polyethylene > polyurethane). (4) Intrathecal morphine infusion (25 mg/ml/0.5 μl/h for 14 days) resulted in intrathecal masses (fibroblasts, interspersed collagen, lymphocytes, and macrophages) arising from meninges proximal to the catheter tip in both polyethylene- and polyurethane-catheterized animals. This closely resembles mass histopathology from intrathecal morphine canine studies.
Conclusions
Continuous intrathecal infusion of morphine leads to pericatheter masses that morphologically resemble those observed in dogs and humans. This small-animal model may be useful for studying spinal drug toxicology in general and the biology of intrathecal granuloma formation in particular.
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Side Effects and Efficacy of Neuraxial Opioids in Pregnant Patients at Delivery: A Comprehensive Review. Drug Saf 2016; 39:381-99. [DOI: 10.1007/s40264-015-0386-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Kirksey MA, Haskins SC, Cheng J, Liu SS. Local Anesthetic Peripheral Nerve Block Adjuvants for Prolongation of Analgesia: A Systematic Qualitative Review. PLoS One 2015; 10:e0137312. [PMID: 26355598 PMCID: PMC4565585 DOI: 10.1371/journal.pone.0137312] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 08/14/2015] [Indexed: 12/13/2022] Open
Abstract
Background The use of peripheral nerve blocks for anesthesia and postoperative analgesia has increased significantly in recent years. Adjuvants are frequently added to local anesthetics to prolong analgesia following peripheral nerve blockade. Numerous randomized controlled trials and meta-analyses have examined the pros and cons of the use of various individual adjuvants. Objectives To systematically review adjuvant-related randomized controlled trials and meta-analyses and provide clinical recommendations for the use of adjuvants in peripheral nerve blocks. Methods Randomized controlled trials and meta-analyses that were published between 1990 and 2014 were included in the initial bibliographic search, which was conducted using Medline/PubMed, Cochrane Central Register of Controlled Trials, and EMBASE. Only studies that were published in English and listed block analgesic duration as an outcome were included. Trials that had already been published in the identified meta-analyses and included adjuvants not in widespread use and published without an Investigational New Drug application or equivalent status were excluded. Results Sixty one novel clinical trials and meta-analyses were identified and included in this review. The clinical trials reported analgesic duration data for the following adjuvants: buprenorphine (6), morphine (6), fentanyl (10), epinephrine (3), clonidine (7), dexmedetomidine (7), dexamethasone (7), tramadol (8), and magnesium (4). Studies of perineural buprenorphine, clonidine, dexamethasone, dexmedetomidine, and magnesium most consistently demonstrated prolongation of peripheral nerve blocks. Conclusions Buprenorphine, clonidine, dexamethasone, magnesium, and dexmedetomidine are promising agents for use in prolongation of local anesthetic peripheral nerve blocks, and further studies of safety and efficacy are merited. However, caution is recommended with use of any perineural adjuvant, as none have Food and Drug Administration approval, and concerns for side effects and potential toxicity persist.
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Affiliation(s)
- Meghan A Kirksey
- Department of Anesthesiology, Hospital for Special Surgery, New York, New York, United States of America; Department of Anesthesiology, Weill College of Medicine at Cornell University, New York, New York, United States of America
| | - Stephen C Haskins
- Department of Anesthesiology, Hospital for Special Surgery, New York, New York, United States of America; Department of Anesthesiology, Weill College of Medicine at Cornell University, New York, New York, United States of America
| | - Jennifer Cheng
- Department of Anesthesiology, Hospital for Special Surgery, New York, New York, United States of America
| | - Spencer S Liu
- Department of Anesthesiology, Hospital for Special Surgery, New York, New York, United States of America; Department of Anesthesiology, Weill College of Medicine at Cornell University, New York, New York, United States of America
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Chamisha Y, Shamir MH, Merbl Y, Chai O. Reversible paralysis and loss of deep pain sensation after topical intrathecal morphine administration following durotomy. Vet Surg 2014; 44:41-5. [PMID: 24724720 DOI: 10.1111/j.1532-950x.2014.12192.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 02/01/2014] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To report 2 dogs that developed temporary pelvic limb paralysis with loss of deep pain sensation after topical intrathecal morphine administration during spinal surgery. STUDY DESIGN Clinical report. ANIMALS Dogs (n = 2). METHODS A 5-year-old castrated male French Bulldog with a subarachnoid diverticulum at T9-T10 and a 9.5-year-old castrated male Belgian Shepherd dog with a herniated disc at T12-T13 and intradural component, had Gelfoam soaked with morphine placed over the dura mater defect. RESULTS Pelvic limb paralysis and loss of deep pain sensation was noticed immediately after recovery from anesthesia. After intravenous naloxone administration, both dogs immediately regained ambulation and normal pain sensation; however the effect was temporary lasting only a few hours. Permanent resolution of clinical signs occurred 24 hours after surgery. CONCLUSIONS Topical intrathecal morphine administration resulted in temporary pelvic limb paralysis and loss of deep pain sensation. This route of administration should be used cautiously until further determination of the efficacy and adverse effects associated with topical intrathecal morphine administration.
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Affiliation(s)
- Yael Chamisha
- Department of Neurology and Neurosurgery, The Veterinary Teaching Hospital, Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel
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Yaksh TL, Hobo S, Peters C, Osborn KG, Richter PJ, Rossi SS, Grafe MR, Eisenach JC. Preclinical toxicity screening of intrathecal oxytocin in rats and dogs. Anesthesiology 2014; 120:951-61. [PMID: 24492326 PMCID: PMC5392224 DOI: 10.1097/aln.0000000000000148] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Anatomic, physiologic, and behavioral studies in animals suggest that spinally released oxytocin should produce analgesia in humans and may also protect from chronic pain after injury. In this article, the authors report preclinical toxicity screening of oxytocin for intrathecal delivery. METHODS Intrathecal oxytocin, 11 μg (6 U) or vehicle, was injected intrathecally in 24 rats, followed by frequent behavioral assessment and histologic examination of spinal contents 2 or 14 days after injection. In three dogs, a range of intrathecal oxytocin doses (18 to 550 μg in 0.5 ml) was injected followed by physiologic, biochemical, and behavioral assessments. Ten dogs were then randomized to receive five daily injections of intrathecal oxytocin, 550 μg in 0.5 ml, or vehicle with similar assessments and, necropsy and histologic analysis were conducted 2 days later. RESULTS In rats, intrathecal oxytocin resulted in transient scratching and itching behaviors, without other differences from vehicle. There was no behavioral, gross anatomic, or histologic evidence of neurotoxicity. Dose ranging in dogs suggested mild effects on motor tone, blood pressure, and heart rate at the 550 μg dose. Repeated boluses in dogs did not produce behavioral, biochemical, neurological, gross anatomic, or histologic evidence of neurotoxicity. CONCLUSIONS Substances, including natural neurotransmitters, may be toxic when administered in pharmacologic doses in the spinal cord. This preclinical toxicity screen in two species suggests that bolus injections of oxytocin in concentrations up to 1,100 μg/ml are unlikely to cause neurotoxicity. The authors also support cautious clinical application of intrathecal oxytocin under regulatory supervision.
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Affiliation(s)
- Tony L. Yaksh
- Department of Anesthesiology, University of California, San Diego (UCSD), CA
| | - Shotaro Hobo
- Department of Anesthesiology, Wake Forest School of Medicine (WFSM), Winston-Salem, NC
| | - Christopher Peters
- Department of Anesthesiology, Wake Forest School of Medicine, WFSM, Winston-Salem, NC
| | - Kent G. Osborn
- Diagnostic Laboratory, Animal Care Program, University of California, San Diego,(UCSD), CA
| | - Philip J. Richter
- Animal Care Program, Department of Pathology, University of California, San Diego,(UCSD), CA
| | - Steven S. Rossi
- Project Scientist, Anesthesiology Research laboratory, (UCSD), CA
| | - Marjorie R. Grafe
- Department of Pathology Medical Director, Neuropathology Oregon Health Sciences University, Portland, OR
| | - James C. Eisenach
- Department of Anesthesiology, Wake Forest School of Medicine, WFSM, Winston-Salem, NC
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Role of meningeal mast cells in intrathecal morphine-evoked granuloma formation. Anesthesiology 2013; 118:664-78. [PMID: 23426209 DOI: 10.1097/aln.0b013e31828351aa] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Intrathecal morphine forms granulomas that arise from the adjacent arachnoid membrane. The authors propose that these inflammatory cells exit the meningeal vasculature secondary to meningeal mast cell degranulation. METHODS Three sets of experiments were accomplished in dogs: (1) ex vivo meningeal mast cell degranulation (histamine release was measured ex vivo from canine dura incubated with opiates); (2) in vivo cutaneous mast cell degranulation (flare areas on the dog abdomen were measured after subcutaneous opiates); and (3) in vivo granuloma pharmacology. Dogs with lumbar intrathecal catheters received infusion of intrathecal saline or intrathecal morphine. Intrathecal morphine dogs received (1) no other treatment (control); (2) twice-daily subcutaneous naltrexone; (3) intrathecal co-infusion of cromolyn; or (4) twice-daily subcutaneous cromolyn for the 24- to 28-day study course. RESULTS Morphine but not fentanyl evoked dural histamine release, which was blocked by cromolyn but not naloxone. Wheal/flare was produced by subcutaneous morphine, methadone, hydromorphone, but not fentanyl, and was unaffected by naltrexone but prevented by cromolyn. Granulomas occurred in all dogs receiving intrathecal morphine (15 of 15); subcutaneous naltrexone had no effect on granulomas (six of six) but was reduced by concurrent intrathecal cromolyn (zero of five) or twice-daily subcutaneous cromolyn (one of five). CONCLUSIONS The pharmacology of cutaneous/dural mast cell degranulation and intrathecal granulomas are comparable, not mediated by opioid receptors, and reduced by agents preventing mast cell degranulation. If an agent produces cutaneous mast cell degranulation at concentrations produced by intrathecal delivery, the agent may initiate granulomas.
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Harkouk H, de Préville G, Benhamou D. Hypothermie profonde après rachianesthésie et morphine intrathécale après césarienne : un nouveau cas clinique. ACTA ACUST UNITED AC 2013; 32:53-5. [DOI: 10.1016/j.annfar.2012.10.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Accepted: 10/11/2012] [Indexed: 10/27/2022]
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Yaksh TL, Steinauer JJ, Veesart SL, Malkmus SA. Alfentanil: correlations between absence of effect upon subcutaneous mast cells and absence of granuloma formation after intrathecal infusion in the dog. Neuromodulation 2012; 16:459-66; discussion 466. [PMID: 23170763 DOI: 10.1111/j.1525-1403.2012.00534.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 09/20/2012] [Accepted: 09/28/2012] [Indexed: 12/11/2022]
Abstract
BACKGROUND We hypothesize that intrathecal (IT) granulomas arising from the IT infusion of several opiates may result from the degranulation of meningeal mast cells (MC). Given functional covariance between cutaneous and meningeal MC, we propose that opioids that do not degranulate cutaneous MC will not produce a granuloma. An opioid meeting this criteria is the phenylpiperadine alfentanil HCl. METHODS Three experiments were accomplished in dogs. 1) Cutaneous MC degranulation. Flare areas on the dog abdomen were measured after intradermal alfentanil, morphine, or compound 48-80. 2) Dose ranging of analgesic effects of IT alfentanil infusion. Dogs with lumbar IT catheters received continuous infusion for 24 hours of different concentrations (1-20 mg/mL/d) of alfentanil and analgesic effects were assessed. 3) Granuloma inducing effects. Dogs received IT alfentanil (20 mg/mL/d; N = 5; 22-28 days) or morphine (12 mg/mL/d; N = 3; 22-30 days) and spinal cord harvested for histopathology after 22-30 days of infusion. RESULTS 1) Intradermal morphine (10 mg/mL) and compound 48-80 (1 mg/mL) but not alfentanil at concentrations up to 20 mg/mL produced a cutaneous flare. IT alfentanil infusion produced increases in thermal escape latency at concentrations as low as 2 mg/mL/day. A significant depression of arousal was noted in the dogs receiving 20 mg/mL. Over the 22- to 30-day infusion period, morphine (12 mg/mL/day) resulted in granulomas in all three animals examined whereas IT alfentanil at 20 mg/mL/day failed to initiate a granuloma in any animal. CONCLUSIONS These results support the hypothesis linking MC degranulation and IT granulomas.
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Affiliation(s)
- Tony L Yaksh
- Anesthesiology Research, Department of Anesthesiology, University of California, San Diego, CA, USA
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Wallace M, Yaksh TL. Characteristics of distribution of morphine and metabolites in cerebrospinal fluid and plasma with chronic intrathecal morphine infusion in humans. Anesth Analg 2012; 115:797-804. [PMID: 22822192 DOI: 10.1213/ane.0b013e3182645dfd] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Despite widespread use of chronic intrathecal (IT) infusions of morphine, there is little systematic human work evaluating the steady state morphine concentrations or cerebrospinal (CSF) chemistry after long-term IT morphine delivery. We sought to address these issues in patients receiving chronic IT morphine infusion. METHODS Pain patients with implanted catheters and pumps (range: 127 to 2165 days), receiving a stable dosing (>1 week) of IT morphine by infusion, were entered into the study. The following sequence was performed: (1) estimation of pain score; (2) radiograph localization of catheter tip; (3) percutaneous sampling of lumbar CSF at the L4 to 5 or L5-S1 space. CSF/plasma samples were assayed for chemistry, and morphine and its 3/6 glucuronide metabolites (M3G, M6G) by liquid chromatography mass spectrometry. RESULTS Nineteen patients were enrolled. CSF samples were obtained from 16 subjects. Three patients were not included in the primary analysis because 1 catheter was epidural, 1 catheter was fractured, and 1 had a granuloma at the catheter tip. Of the 13 sampled patients, the range of daily doses, rates, and concentrations were 1.6 to 25 mg/d and 0.1 to 1 mL/d, 5 to 50 mg/mL, respectively. The principal observations were as follows: (i) morphine, M3G, and M6G were present in the CSF and plasma and showed a significant regression slope when plotted versus daily dose; (ii) in contrast, the regression slope of the group ratio morphine:M3G:M6G plotted versus daily dose in CSF or plasma was not different from zero; (iii) plotting "normalized" CSF analyte concentration (e.g., concentration at site/daily IT morphine dose) against the segmental distance of the sampling site from the catheter tip revealed a significant decline in concentration of morphine, but not of conjugates as a function of distance from the catheter tip; (iv) plotting CSF protein, glucose, and red and white cell counts versus daily morphine dose or morphine concentration at the sampling site revealed no significant regression; and (v) patients with a catheter failure or a granuloma showed reduced concentrations of morphine in their CSF. CONCLUSION Chronic infusion of morphine shows high concentrations, which correlate with the infusion dose and the proximity of the sampling site to the infusion site with no effects on CSF chemistry.
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Affiliation(s)
- Mark Wallace
- Department of Anesthesiology, University of California-San Diego, La Jolla, CA, USA.
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Yaksh TL, de Kater A, Dean R, Best BM, Miljanich GP. Pharmacokinetic analysis of ziconotide (SNX-111), an intrathecal N-type calcium channel blocking analgesic, delivered by bolus and infusion in the dog. Neuromodulation 2012; 15:508-19; discussion 519. [PMID: 22748108 DOI: 10.1111/j.1525-1403.2012.00479.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND PURPOSE Ziconotide is a peptide that blocks N-type calcium channels and is antihyperalgesic after intrathecal (IT) delivery. We here characterize the spinal kinetics of IT bolus and infused ziconotide in dog. EXPERIMENTAL APPROACH Male beagle dogs (N= 5) were prepared with chronic IT lumbar injection and cerebrospinal fluid (LCSF) sampling catheters connected to vest-mounted pumps. Each dog received the following: 1) IT bolus ziconotide (10 µg + 1 µCi (3) H-inulin); 2) IT infusion for 48 hours of ziconotide (1 µg/100 µL/hour); 3) IT infusion for 48 hours of ziconotide (5 µg/100 µL/hour); and 4) intravenous injection of ziconotide (0.1 mg/kg). After IT bolus, LCSF ziconotide and inulin showed an initial peak and biphasic (distribution/elimination) clearance (ziconotide T(1/2-α/β) = 0.14 and 1.77 hours, and inulin T(1/2-α/β) = 0.16 and 3.88 hours, respectively). The LCSF : plasma ziconotide concentration ratio was 20,000:1 at 30 min and 30:1 at eight hours. IT infusion of 1 and then 5 µg/hour resulted in LCSF concentrations that peaked by eight hours and remained stable at 343 and 1380 ng/mL, respectively, to the end of the 48-hour infusions. Terminal elimination T(1/2) after termination of continuous infusion was 2.47 hours. Ziconotide LCSF : cisternal CSF : plasma concentration ratios after infusion of 1 and 5 µg/hour were 1:0.017:0.001 and 1:0.015:0.003, respectively. IT infusion of ziconotide at 1 µg/hour inhibited thermal skin twitch by 24 hours and produced modest trembling, ataxia, and decreased arousal. Effects continued through the 48-hour infusion period, increased in magnitude during the subsequent 5 µg/hour infusion periods, and disappeared after drug clearance. CONCLUSIONS AND IMPLICATIONS After IT bolus or infusion, ziconotide displays linear kinetics that are consistent with a hydrophilic molecule of approximately 2500 Da that is cleared slightly more rapidly than inulin from the LCSF. Behavioral effects were dose dependent and reversible.
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Affiliation(s)
- Tony L Yaksh
- Department of Anesthesiology, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
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Persistent hypothermia after intrathecal morphine: case report and literature review. Can J Anaesth 2011; 59:384-8. [PMID: 22161244 DOI: 10.1007/s12630-011-9650-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 12/01/2011] [Indexed: 02/07/2023] Open
Abstract
PURPOSE To describe a case of persistent hypothermia following spinal anesthesia with intrathecal morphine. CLINICAL FEATURES Following elective right total knee arthroplasty under spinal anesthesia with isobaric 0.5% bupivacaine 11 mg, fentanyl 15 μg, and preservative-free morphine 150 μg, a 57-yr-old female (93.5 kg, 151 cm) developed postoperative hypothermia with a nadir rectal temperature of 33.6°C four hours after surgery. At times, her temperature could not be measured by tympanic, temporal arterial, oral, axillary, or rectal routes. In spite of the low temperature, the patient complained of feeling hot and was diaphoretic without shivering. With the exception of her temperature, her vital signs were normal postoperatively, and aside from hyperglycemia, complete blood count, electrolytes, thyroid-stimulating hormone, serum cortisol, troponin, and twelve-lead electrocardiogram were normal. Her temperature did not respond to warming efforts with a forced-air warming blanket, infusion of warmed intravenous crystalloid, and hourly bladder irrigation with warm saline through an indwelling urinary catheter. Normothermia returned after she received a small dose of sublingual lorazepam eight hours after surgery. The remainder of her postoperative stay was uneventful. CONCLUSION Patients undergoing spinal anesthesia with intrathecal morphine may develop postoperative hypothermia that is resistant to warming measures. This complication may be treated successfully with lorazepam.
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Validation of a preclinical spinal safety model: effects of intrathecal morphine in the neonatal rat. Anesthesiology 2010; 113:183-99. [PMID: 20526189 DOI: 10.1097/aln.0b013e3181dcd6ec] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Preclinical studies demonstrate increased neuroapoptosis after general anesthesia in early life. Neuraxial techniques may minimize potential risks, but there has been no systematic evaluation of spinal analgesic safety in developmental models. We aimed to validate a preclinical model for evaluating dose-dependent efficacy, spinal cord toxicity, and long-term function after intrathecal morphine in the neonatal rat. METHODS Lumbar intrathecal injections were performed in anesthetized rats aged postnatal day (P) 3, 10, and 21. The relationship between injectate volume and segmental spread was assessed postmortem and by in vivo imaging. To determine the antinociceptive dose, mechanical withdrawal thresholds were measured at baseline and 30 min after intrathecal morphine. To evaluate toxicity, doses up to the maximum tolerated were administered, and spinal cord histopathology, apoptosis, and glial response were evaluated 1 and 7 days after P3 or P21 injection. Sensory thresholds and gait analysis were evaluated at P35. RESULTS Intrathecal injection can be reliably performed at all postnatal ages and injectate volume influences segmental spread. Intrathecal morphine produced spinally mediated analgesia at all ages with lower dose requirements in younger pups. High-dose intrathecal morphine did not produce signs of spinal cord toxicity or alter long-term function. CONCLUSIONS The therapeutic ratio for intrathecal morphine (toxic dose/antinociceptive dose) was at least 300 at P3 and at least 20 at P21 (latter doses limited by side effects). These data provide relative efficacy and safety for comparison with other analgesic preparations and contribute supporting evidence for the validity of this preclinical neonatal safety model.
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Valverde A. Epidural Analgesia and Anesthesia in Dogs and Cats. Vet Clin North Am Small Anim Pract 2008; 38:1205-30, v. [DOI: 10.1016/j.cvsm.2008.06.004] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Low-dose sufentanil dœs not potentiate intra-thecal morphine for perioperative analgesia after major colorectal surgery. Can J Anaesth 2007; 54:811-7. [DOI: 10.1007/bf03021708] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Lou L, Orbegozo M, King CL. Rationale and technique for single and multiple drug combinations in long-term intrathecal infusions. Pain Pract 2006; 1:68-78; quiz 79-80. [PMID: 17129286 DOI: 10.1046/j.1533-2500.2001.01010.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- L Lou
- International Pain Institute, Texas Tech University Health Sciences Center, Lubbock, Texas 79413, USA
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Lee IH, Lee IO. Antipruritic and antiemetic effect of epidural droperidol. Eur J Anaesthesiol 2006; 23:213-8. [PMID: 16430793 DOI: 10.1017/s0265021505002218] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2005] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND OBJECTIVES This study was designed to investigate whether single epidural droperidol or continuous epidural droperidol inhibit pruritus and postoperative nausea and vomiting induced by postoperative continuous epidural fentanyl administration, and to identify the optimal method of administering epidural droperidol. METHODS 120 ASA I-II patients undergoing subtotal gastrectomy with general anaesthesia combined with epidural anaesthesia were randomly allocated into three groups: control (no droperidol), single injection (droperidol 2.5 mg) and continuous group (droperidol 2.5 mg 2 day(-1)). Postoperatively the frequency and severity of pruritus and postoperative nausea and vomiting in all groups were compared during 48 h. RESULTS The frequency and severity of pruritus was significantly lower in both single injection and continuous groups than control group after epidural fentanyl administration (P < 0.05). The frequency and severity of postoperative nausea and vomiting was significantly lower in single injection group than control group after epidural fentanyl administration (P < 0.05). CONCLUSION Epidural continuous droperidol is effective for reducing pruritus, and single epidural droperidol injection is effective for reducing pruritus and postoperative nausea and vomiting induced by postoperative continuous epidural fentanyl analgesia.
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Affiliation(s)
- I H Lee
- Department of Anesthesiology, Samsung Cheil Hospital, Sungkyunkwan University School of Medicine, Seoul, South Korea
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Yaksh TL, Allen JW. Preclinical insights into the implementation of intrathecal midazolam: a cautionary tale. Anesth Analg 2004; 98:1509-1511. [PMID: 15155298 DOI: 10.1213/01.ane.0000121768.79904.7f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Tony L Yaksh
- Department of Anesthesiology, University of California, San Diego
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Spinal Cord Compression From Intrathecal Catheter-Tip Inflammatory Mass. Reg Anesth Pain Med 2004. [DOI: 10.1097/00115550-200405000-00011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Allen JW, Yaksh TL. Assessment of acute thermal nociception in laboratory animals. METHODS IN MOLECULAR MEDICINE 2004; 99:11-23. [PMID: 15131325 DOI: 10.1385/1-59259-770-x:139] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Models of acute nociception using a thermal stimulus are widely employed as screening methods for nociceptive properties of new drug compounds. In this chapter, detailed descriptions for conducting of two of the most commonly used models; the hot plate test and the "Hargreaves test," are described. These models are applicable to both rats and mice and have the advantage of allowing repeated and multiple testing using a single animal because the stimulus is transitory and produces no tissue damage. Additionally, a modification of these models using a skin-twitch reflex that is applicable to large laboratory animals such a dogs or sheep is described. Guidance concerning potential confounding variable are discussed, as are tips for reducing variably among testing sessions.
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Affiliation(s)
- Jeffrey W Allen
- Department of Anesthesiology, University of California San Diego, La Jolla, USA
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Abstract
Systemic administration of analgesics can lead to serious adverse side effects compromising therapeutic benefit in some patients. Information coding pain transmits along an afferent neuronal network, the first synapses of which reside principally in the spinal cord. Delivery of compounds to spinal cord, the intended site of action for some analgesics, is potentially a more efficient and precise method for inhibiting the pain signal. Activation of specific proteins that reside in spinal neuronal membranes can result in hyperpolarization of secondary neurons, which can prevent transmission of the pain signal. This is one of the mechanisms by which opioids induce analgesia. The spinal cord is enriched in such molecular targets, the activation of which inhibit the transmission of the pain signal early in the afferent neuronal network. This review describes the pre-clinical models that enable new target discovery and development of novel analgesics for site-directed pain management.
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Hypothermia and Excessive Sweating Following Intrathecal Morphine in a Parturient Undergoing Cesarean Delivery. Reg Anesth Pain Med 2003. [DOI: 10.1097/00115550-200303000-00012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Krames E. Implantable devices for pain control: spinal cord stimulation and intrathecal therapies. Best Pract Res Clin Anaesthesiol 2002; 16:619-49. [PMID: 12516895 DOI: 10.1053/bean.2002.0263] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Untreated chronic pain is costly to society and to the individual suffering from it. The treatment of chronic pain, a multidimensional disease, should rely on the expertise of varying health care providers and should focus not only on the neurobiological mechanisms of the process but also on the psychosocial aspects of the disease. Implantable devices are costly and invasive, and such efficacious therapies should be used only when more conservative and less costly therapies have failed to provide relief of pain and suffering. Spinal cord stimulation provides neuromodulation of neuropathic, but not nociceptive, pain signals and when used for appropriate indications in the right individuals provides approximately 60-80% long-term pain relief in 60-80% of patients trialled for efficacy. Intrathecal therapies with opioids such as morphine, fentanyl, sufentanil or meperidine--or non-opioids such as clonidine or bupivacaine--provide analgesia in patients with nociceptive or neuropathic pain syndromes. Baclofen, intrathecally, provides profound relief of muscle spasticity due to multiple sclerosis, spinal cord injuries, brain injuries or cerebral palsy.
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Affiliation(s)
- Elliot Krames
- Pacific Pain Treatment Centers and Neuromodulation, Journal of the International Neuromodulation Society, San Francisco, California 94109, USA
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Troncy E, Junot S, Keroack S, Sammut V, Pibarot P, Genevois JP, Cuvelliez S. Results of preemptive epidural administration of morphine with or without bupivacaine in dogs and cats undergoing surgery: 265 cases (1997-1999). J Am Vet Med Assoc 2002; 221:666-72. [PMID: 12216906 DOI: 10.2460/javma.2002.221.666] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine prevalence of adverse effects associated with epidural administration of morphine with or without bupivacaine in dogs and cats undergoing surgery and evaluate effects of epidural administration of morphine on postoperative pain severity. DESIGN Retrospective study. ANIMALS 242 dogs and 23 cats. PROCEDURE Morphine with or without bupivacaine was administered prior to surgery with a Tuohy needle, spinal needle, or epidural catheter. In 18 dogs that underwent surgery twice, results of preemptive epidural administration of morphine with or without bupivacaine were compared with results of systemic administration of oxymorphone and ketoprofen. RESULTS The delivered fraction of isoflurane was significantly lower in animals given morphine and bupivacaine than in animals given morphine alone. Analgesia was of significantly longer duration in dogs given morphine and bupivacaine than in dogs given morphine alone. During anesthesia, mild respiratory and cardiovascular depression was reported. Seven dogs and 2 cats had urine retention, and 2 dogs developed pruritus. Six dogs vomited when a second dose of morphine was given epidurally the day after surgery. Eight of 72 dogs had delayed hair growth. In 18 dogs that underwent surgery twice, the delivered fraction of isoflurane was significantly lower and the duration of analgesia was significantly longer when morphine with or without bupivacaine was given epidurally than when oxymorphone and ketoprofen were given. CONCLUSIONS AND CLINICAL RELEVANCE Results suggest that preemptive epidural administration of morphine with or without bupivacaine is a safe and effective method of inducing long-lasting analgesia in dogs and cats and is superior to standard management of postoperative pain with repeated injection of oxymorphone and ketoprofen.
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MESH Headings
- Analgesia, Epidural/adverse effects
- Analgesia, Epidural/veterinary
- Analgesics, Opioid/administration & dosage
- Analgesics, Opioid/adverse effects
- Anesthetics, Local/administration & dosage
- Anesthetics, Local/adverse effects
- Anesthetics, Local/pharmacology
- Animals
- Bupivacaine/administration & dosage
- Bupivacaine/adverse effects
- Cats/physiology
- Cats/surgery
- Dogs/physiology
- Dogs/surgery
- Female
- Injections, Epidural/veterinary
- Ketoprofen
- Male
- Morphine/administration & dosage
- Morphine/adverse effects
- Oxymorphone
- Pain Measurement/veterinary
- Pain, Postoperative/prevention & control
- Pain, Postoperative/veterinary
- Retrospective Studies
- Safety
- Time Factors
- Treatment Outcome
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Affiliation(s)
- Eric Troncy
- Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, QC, Canada
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Dobrydnjov I, Axelsson K, Samarütel J, Holmström B. Postoperative pain relief following intrathecal bupivacaine combined with intrathecal or oral clonidine. Acta Anaesthesiol Scand 2002; 46:806-14. [PMID: 12139535 DOI: 10.1034/j.1399-6576.2002.460709.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The purpose of the present study was to evaluate the postoperative analgesic and adverse effects of equal doses of oral or intrathecal clonidine in spinal anaesthesia with bupivacaine plain. METHODS Forty-five ASA I-III orthopaedic patients scheduled for osteosynthesis of a traumatic femur fracture were randomised in a double-blind fashion to one of 3 groups. Patients received 15 mg of plain bupivacaine intrathecally (group B) or an intrathecal mixture of bupivacaine 15 mg and clonidine 150 mg (group CIT). In group CPO oral clonidine 150 mg was administered 60 min before intrathecal injection of bupivacaine 15 mg. RESULTS Oral and intrathecal clonidine prolonged the time until the first request for analgesics, 313 +/- 29 and 337 +/- 29 min, respectively, vs. 236 +/- 27 min in group B (P < 0.01). The total 24- h PCA morphine dose was significantly lower in group CIT(19.3 +/- 1.3 mg) compared to groups B and CPO(33.4 +/- 2.0 and 31.2 +/- 3.1 mg). MAP was decreased significantly during the first hour after intrathecal clonidine(14%) and during the first 5 h after oral clonidine(14-19%). HR decreased in CIT during the 5th and 6th postoperative hours(7-9%) and during the first 2 h(9%) in CPO (P < 0.01). The degree of sedation was more pronounced in group CPO during the first 3 h. Four patients had pruritus in group B. CONCLUSIONS Addition of intrathecal clonidine prolonged analgesia and decreased morphine consumption postoperatively more than oral clonidine. Hypotension was more pronounced after oral than after intrathecal clonidine. Intrathecal clonidine is therefore recommended.
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Affiliation(s)
- I Dobrydnjov
- Department of Anesthesiology and Intensive Care, Orebro University Hospital, Sweden.
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Brown DC, Perkowski SZ, Shofer F, Amico JA. Effect of centrally administered opioid receptor agonists on CSF and plasma oxytocin concentrations in dogs. Am J Vet Res 2001; 62:496-9. [PMID: 11327454 DOI: 10.2460/ajvr.2001.62.496] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To measure oxytocin concentrations in blood and CSF following central administration of opioid agonists in dogs. ANIMALS 5 male dogs. PROCEDURE In a crossover design, CSF and blood were collected immediately before and 15 and 30 minutes after cisternal administration of D-Ala2, MePhe4, Gly-ol-enkephalin (DAMGO, a mu-receptor agonist); D-Pen, pCl-Phe4, D-Pen5-enkephalin (a delta-receptor agonist); U50488H (a kappa-receptor agonist); morphine; and saline (0.9% NaCl) solution. RESULTS Plasma oxytocin concentration was significantly increased 15 minutes after administration of DAMGO and 30 minutes after administration of U50488H, compared with concentrations obtained after administration of saline solution. Concentration of oxytocin in CSF was significantly decreased 30 minutes after administration of U50488H, compared with concentration after administration of saline solution. CONCLUSIONS AND CLINICAL RELEVANCE Results suggest that in male dogs, activation of centrally located mu and kappa receptors elicits an overall excitatory effect on neurons that regulate peripheral release of oxytocin, whereas activation of centrally located kappa receptors elicits an overall inhibitory effect on neurons that regulate central release. These results are in contrast to those reported for other species, in which opioids have a pronounced inhibitory effect on release of oxytocin from the neurohypophysis.
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Affiliation(s)
- D C Brown
- Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia 19104-6010, USA
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Lou L, Orbegozo M, King CL. Rationale and Technique for Single and Multiple Drug Combinations in Long‐term Intrathecal Infusions. Pain Pract 2001. [DOI: 10.1111/j.1533-2500.2001.01010.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Leland Lou
- International Pain Institute, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Mauricio Orbegozo
- International Pain Institute, Texas Tech University Health Sciences Center, Lubbock, Texas
| | - Casey L. King
- International Pain Institute, Texas Tech University Health Sciences Center, Lubbock, Texas
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Bennett G, Serafini M, Burchiel K, Buchser E, Classen A, Deer T, Du Pen S, Ferrante FM, Hassenbusch SJ, Lou L, Maeyaert J, Penn R, Portenoy RK, Rauck R, Willis KD, Yaksh T. Evidence-based review of the literature on intrathecal delivery of pain medication. J Pain Symptom Manage 2000; 20:S12-36. [PMID: 10989255 DOI: 10.1016/s0885-3924(00)00204-9] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Evidence-based medicine depends on the existence of controlled clinical trials that establish the safety and efficacy of specific therapeutic techniques. Many interventions in clinical practice have achieved widespread acceptance despite little evidence to support them in the scientific literature; the critical appraisal of these interventions based on accumulating experience is a goal of medicine. To clarify the current state of knowledge concerning the use of various drugs for intraspinal infusion in pain management, an expert panel conducted a thorough review of the published literature. The exhaustive review included 5 different groups of compounds, with morphine and bupivacaine yielding the most citations in the literature. The need for additional large published controlled studies was highlighted by this review, especially for promising agents that have been shown to be safe and efficacious in recent clinical studies.
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Affiliation(s)
- G Bennett
- Department of Neurology, MCP Hahnemann University, Philadelphia, PA, USA
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Neath PJ, Brown DC, Hughes D, Perkowski SZ. The hemodynamic effects of intrathecal oxytocin in normal dogs. Vet Surg 2000; 29:272-7. [PMID: 10871229 DOI: 10.1053/jvet.2000.5613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To evaluate the hemodynamic effects produced by intrathecal administration of oxytocin in healthy isoflurane-anesthetized dogs. STUDY DESIGN Prospective single-dose trial. ANIMAL POPULATION Six healthy purpose-bred adult dogs weighing between 7.3 and 14.5 kg. METHODS Dogs were anesthetized with isoflurane and instrumented. Oxytocin at a dosage of 1.6 microg/kg was administered intrathecally at the cisternal space at time 0. Hemodynamic data were recorded immediately before and at 1, 5, 15, 30, and 60 minutes after oxytocin administration. Statistical analysis included an analysis of variance (ANOVA) for repeated measures over time. A P < .05 was considered significant. RESULTS Baseline values +/- standard error of the mean for heart rate, mean arterial pressure, central venous pressure, cardiac output, systemic vascular resistance, mean pulmonary arterial pressure, pulmonary arterial occlusion pressure, and pulmonary vascular resistance were 101 +/- 11 beats/minute, 76 +/- 7 mm Hg, 4 +/- 4 mm Hg, 1.9 +/- 0.7 L/min, 3834 +/- 2556 dynes x sec/cm5, 14 +/- 3 mm Hg, 4 +/- 2 mm Hg, and 430 +/- 201 dynes x sec/cm5, respectively. Variations from the baseline values were seen in all parameters after intrathecal oxytocin administration, but no statistically significant differences were found. CONCLUSION The intrathecal injection of 1.6 microg/kg of oxytocin is associated with minimal hemodynamic effects during isoflurane anesthesia. CLINICAL RELEVANCE This study revealed no clinically significant deleterious effects from the intrathecal administration of oxytocin, and investigations into its use as a perioperative analgesic are therefore warranted.
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Affiliation(s)
- P J Neath
- Department of Clinical Studies, University of Pennsylvania, School of Veterinary Medicine, Philadelphia 19104-6010, USA
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Yaksh TL, Provencher JC, Rathbun ML, Myers RR, Powell H, Richter P, Kohn FR. Safety assessment of encapsulated morphine delivered epidurally in a sustained-release multivesicular liposome preparation in dogs. Drug Deliv 2000; 7:27-36. [PMID: 10895417 DOI: 10.1080/107175400266768] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
We have shown that the epidural (EPI) delivery of morphine encapsulated in multivesicular liposomes (DepoFoam drug delivery system) produces a sustained clearance of morphine and a prolonged analgesia. We have sought to subsequently determine the likelihood of deleterious effects on local tissue of repetitive epidural injections of this encapsulated morphine preparation (C0401). Beagle dogs were prepared according to protocol approved by the Institutional Animal Care and Use Committee under volatile general anesthesia with chronic lumbar EPI catheters and subcutaneous injection ports. Male and female dogs (three groups) received a total of 4 EPI injections at 8-day intervals of 3 mL of C0401 (10 mg/mL morphine) (N = 6), DepoFoam vehicle (N = 6), or 0.9% sodium chloride (N = 6). Following EPI-C0401, but not saline or DepoFoam vehicle, there were transient (< 72 hr) decreases in food consumption, arousal, hindlimb muscle tone, and body temperature. Heart rate was unaltered, but there were modest decreases in blood pressure and respiratory rate, which persisted for 24-72 hr after C0401. No persistent changes in sensory/motor function, body weight, or stool/urine production were observed. Cerebrospinal fluid, blood chemistry, and urinalysis performed at surgery and on the day of sacrifice (24 hr after the last dose) were within normal ranges. Gross pathology at necropsy was unremarkable. Spinal histopathology findings were judged to be minimal (e.g., modest pericatheter inflammation and fibrosis) and present in all dogs. However, a statistical trend in the rank order of pathology scores was noted (Saline < DepoFoam vehicle < C0401). Repeated EPI injection of C0401 at the maximum dose that could be administered (30 mg) resulted in moderate, transient behavioral and physiological effects after each injection, consistent with morphine administration, and a modest effect on cord histopathology. This level of pathology is reflected in the lack of change observed in cerebrospinal fluid and lack of neurological findings. These results suggest that C0401 is without significant pathological effects at this dose after repeated epidural delivery in dogs.
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Affiliation(s)
- T L Yaksh
- Department of Anesthesiology, University of California, San Diego, La Jolla 92093-0818, USA
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Abstract
Overall, most spinal drugs in clinical use have been poorly studied for spinal cord and nerve root toxicity. Laboratory studies indicate that all local anesthetics are neurotoxic in high concentrations and that lidocaine and tetracaine have neurotoxic potential in clinically used concentrations. However, spinal anesthesia (including lidocaine and tetracaine) has a long and enviable history of safety. Spinal analgesics such as morphine, fentanyl, sufentanil, clonidine, and neostigmine seem to have a low potential for neurotoxicity based on laboratory and extensive clinical use. Most antioxidants, preservatives, and excipients used in commercial formulations seem to have a low potential for neurotoxicity. In addition to summarizing current information, we hope that this review stimulates future research on spinal drugs to follow a systematic approach to determining potential neurotoxicity. Such an approach would examine histologic, physiologic, and behavioral testing in several species, followed by cautious histologic, physiologic, and clinical testing in human volunteers and patients with terminal cancer refractory to conventional therapy.
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Affiliation(s)
- P S Hodgson
- Department of Anesthesiology, Virginia Mason Medical Center, Seattle, Washington 98111, USA
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Characteristics of Tolerance to Somatic and Visceral Antinociception After Continuous Epidural Infusion of Morphine in Rats. Anesth Analg 1998. [DOI: 10.1097/00000539-199812000-00024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Characteristics of Tolerance to Somatic and Visceral Antinociception After Continuous Epidural Infusion of Morphine in Rats. Anesth Analg 1998. [DOI: 10.1213/00000539-199812000-00024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wagemans MF, van der Valk P, Spoelder EM, Zuurmond WW, de Lange JJ. Neurohistopathological findings after continuous intrathecal administration of morphine or a morphine/bupivacaine mixture in cancer pain patients. Acta Anaesthesiol Scand 1997; 41:1033-8. [PMID: 9311403 DOI: 10.1111/j.1399-6576.1997.tb04832.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND As the number of terminal cancer patients receiving continuous intrathecal infusion of opioids and local anesthetics for relief of pain increases, we decided to investigate the post-mortem findings of the spinal cord, meninges and nerve roots of patients after continuous intrathecal administration of morphine and combined with bupivacaine. METHODS Neurohistopathological findings were obtained from 10 cancer patients [2 men and 8 women, 29-69 (median 52) yrs old] and 4 controls [4 men, 46-75 (median 64) yrs old]. The cancer patients had been treated for a mean of 98 (range 8-452) d with morphine/NaCl 0.9% or morphine/bupivacaine, administered through a polyamide lumbar catheter. Concomitant radiation therapy and chemotherapeutic drugs had been given to 5 and 6 patients, respectively. Cumulative doses of morphine ranged from 22 to 3895 mg, those of bupivacaine from 0 to 3250 mg and of sodium metabisulfite (antioxidant) from 0.6 to 97.4 mg. RESULTS No macroscopic abnormalities of the catheter tract, dura, leptomeninges, nerve roots or spinal cord were found. Microscopically, focal foreign body giant cells were seen in 2 cases in the area of the catheter pathway both without any sign of inflammation. In one case treated for 103 d, an intrathecal reaction was found. This consisted of small aggregates of lymphocytes predominantly in the leptomeninges and focally in the cord parenchyma. No abnormalities were found in the other cases when using hematoxylin-eosin and Kluver or Bodian stained specimens, indicating neither myelin nor axonal damage. Microglial reactions were similar in both cancer patients and controls. CONCLUSION The discrete and limited neurohistopathological findings in both catheter patients and controls suggest that intrathecal infusion of morphine and bupivacaine via a polyamide catheter is devoid of significant neurotoxic effects in cancer patients.
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Affiliation(s)
- M F Wagemans
- Department of Anesthesiology, Academic Hospital Vrije Universiteit, Amsterdam, The Netherlands
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Gurun MS, Leinbach R, Moore L, Lee CS, Owen MD, Eisenach JC. Studies on the Safety of Glucose and Paraben-Containing Neostigmine for Intrathecal Administration. Anesth Analg 1997. [DOI: 10.1213/00000539-199708000-00014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Gurun MS, Leinbach R, Moore L, Lee CS, Owen MD, Eisenach JC. Studies on the safety of glucose and paraben-containing neostigmine for intrathecal administration. Anesth Analg 1997; 85:317-23. [PMID: 9249107 DOI: 10.1097/00000539-199708000-00014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Initial toxicity testing of neostigmine for intrathecal (IT) injection was performed with preservative-free isobaric solution, yet currently available formulations contain the preservatives methyl- and propylparaben and are usually mixed with glucose to yield hyperbaric solutions. Since it has been proposed that preservatives and hyperbaricity increase the risk of neurotoxicity after IT injection, we examined the safety of chronically administered IT neostigmine containing these additives in sheep and rats. Rats receiving daily IT injections of glucose alone or of glucose with preservative-containing neostigmine, 5 and 10 microg, exhibited dose-related antinociception, tremor, and rigidity. In comparison to our previously published study of neostigmine injection in solution without glucose, rats receiving IT neostigmine with glucose displayed less rigidity, tremor, and salivation. Sheep receiving daily injection of glucose alone or with preservative-containing neostigmine, 1 mg, for 14 days exhibited no histologic evidence of neurotoxicity, nor did they exhibit abnormalities in cerebrospinal fluid chemistry aside from those caused by inflammation. Spinal cord histologic examination in both species revealed fibrosis and inflammation secondary to the catheter without evidence of neuronal damage. These studies support the safety of paraben- and glucose-containing IT neostigmine.
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Affiliation(s)
- M S Gurun
- Department of Anesthesia, Bowman Gray School of Medicine, Winston-Salem, North Carolina 27157-1009, USA
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