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Hitosugi N, Hotta K, Taketa Y, Takamizawa R, Fujii Y, Ikegami R, Tamiya H, Inoue T, Tsubaki A. The effect of sepsis and reactive oxygen species on skeletal muscle interstitial oxygen pressure during contractions. Microcirculation 2024; 31:e12833. [PMID: 37800537 DOI: 10.1111/micc.12833] [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: 05/29/2023] [Revised: 09/09/2023] [Accepted: 09/23/2023] [Indexed: 10/07/2023]
Abstract
OBJECTIVE This study aims to examine the effect of sepsis on the dynamics of skeletal muscle partial oxygen pressure during muscle contractions as well as the effect of reactive oxygen species (ROS) scavenger (ascorbic acid, Asc). METHODS Twenty-seven male Sprague-Dawley rats (2-3 months old) were randomly assigned to three groups; sham, cecal ligation and puncture (CLP), or CLP plus ascorbic acid treatment group (CLP + Asc). Electrical stimuli-induced muscle contractions and partial oxygen pressure measurements were performed at 3 h after CLP. The interstitial oxygen pressure (PO2 is) in the spinotrapezius muscle was measured by the phosphorescence quenching method. RESULTS The PO2 is at rest was not different between the three groups. The PO2 is decreased from rest to contraction in all groups. Compared to the sham, the time to decrease PO2 is was significantly faster in CLP but not in CLP + Asc (p < .05). Compared to the sham, the PO2 is during muscle contractions was significantly lower in both CLP and CLP + Asc (p < .05, respectively). CONCLUSIONS Our results suggest that CLP-induced sepsis accelerated the decay of PO2 is at the onset of muscle contractions and maintained a low level of PO2 is during muscle contractions.
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Affiliation(s)
- Naoki Hitosugi
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
| | - Kazuki Hotta
- Department of Rehabilitation Sciences, Graduate School of Medical Sciences, Kitasato University, Sagamihara, Japan
- Department of Rehabilitation, Kitasato University School of Allied Health Sciences, Sagamihara, Japan
| | - Yoshikazu Taketa
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan
| | - Ren Takamizawa
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
| | - Yutaka Fujii
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
- Department of Clinical Engineering and Medical Technology, Niigata University of Health and Welfare, Niigata, Japan
| | - Ryo Ikegami
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan
| | - Hajime Tamiya
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan
| | - Tatsuro Inoue
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan
| | - Atsuhiro Tsubaki
- Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata, Japan
- Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan
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Belbis MD, Yap Z, Hobart SE, Ferguson SK, Hirai DM. Effects of acute phosphodiesterase type 5 inhibition on skeletal muscle interstitial PO 2 during contractions and recovery. Nitric Oxide 2024; 142:16-25. [PMID: 37979932 DOI: 10.1016/j.niox.2023.11.004] [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: 07/10/2023] [Revised: 10/26/2023] [Accepted: 11/14/2023] [Indexed: 11/20/2023]
Abstract
The oxygen partial pressure within the interstitial space (PO2is; mmHg) provides the driving force for oxygen diffusion into the myocyte thereby supporting oxidative phosphorylation. We tested the hypothesis that potentiation of the nitric oxide pathway with sildenafil (phosphodiesterase type 5 inhibitor) would enhance PO2is during muscle metabolic transitions, thereby slowing PO2is on- and accelerating PO2is off-kinetics. The rat spinotrapezius muscle (n = 17) was exposed for PO2is measurements via phosphorescence quenching under control (CON), low-dose sildenafil (1 mg/kg i.a., SIL1) and high-dose sildenafil (7 mg/kg i.a., SIL7). Data were collected at rest and during submaximal twitch contractions (1 Hz, 4-6 V, 3 min) and recovery (3 min). Mean arterial blood pressure (MAP; mmHg) was reduced with both SIL1 (pre:132 ± 5; post:99 ± 5) and SIL7 (pre:111 ± 6; post:99 ± 4) (p < 0.05). SIL7 elevated resting PO2is (18.4 ± 1.1) relative to both CON (15.7 ± 0.7) and SIL1 (15.2 ± 0.7) (p < 0.05). In addition, SIL7 increased end-recovery PO2is (17.7 ± 1.6) compared to CON (12.8 ± 0.9) and SIL1 (13.4 ± 0.8) (p < 0.05). The overall PO2is response during recovery (i.e., area under the PO2is curve) was greater in SIL7 (4107 ± 444) compared to CON (3493 ± 222) and SIL1 (3114 ± 205 mmHg s) (p < 0.05). Contrary to our hypothesis, there was no impact of acute SIL (1 or 7 mg/kg) on the speed of the PO2is response during contractions or recovery (p > 0.05). However, sildenafil lowered MAP and improved skeletal muscle interstitial oxygenation in healthy rats. Specifically, SIL7 enhanced PO2is at rest and during recovery from submaximal muscle contractions. Potentiation of the nitric oxide pathway with sildenafil enhances microvascular blood-myocyte O2 transport and is expected to improve repeated bouts of contractile activity.
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Affiliation(s)
- Michael D Belbis
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, USA; Department of Exercise Science, Aurora University, Aurora, IL, USA
| | - Zhen Yap
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, USA
| | - Sara E Hobart
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, USA
| | - Scott K Ferguson
- Department of Human Factors and Behavioral Neurobiology, Embry-Riddle Aeronautical University, Daytona Beach, FL, USA
| | - Daniel M Hirai
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, USA.
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Witthauer L, Roussakis E, Cascales JP, Goss A, Li X, Cralley A, Yoeli D, Moore HB, Wang Z, Wang Y, Li B, Huang CA, Moore EE, Evans CL. Development and in-vivo validation of a portable phosphorescence lifetime-based fiber-optic oxygen sensor. Sci Rep 2023; 13:14782. [PMID: 37679415 PMCID: PMC10484954 DOI: 10.1038/s41598-023-41917-5] [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: 04/14/2023] [Accepted: 09/04/2023] [Indexed: 09/09/2023] Open
Abstract
Oxygenation is a crucial indicator of tissue viability and function. Oxygen tension ([Formula: see text]), i.e. the amount of molecular oxygen present in the tissue is a direct result of supply (perfusion) and consumption. Thus, measurement of [Formula: see text] is an effective method to monitor tissue viability. However, tissue oximetry sensors commonly used in clinical practice instead rely on measuring oxygen saturation ([Formula: see text]), largely due to the lack of reliable, affordable [Formula: see text] sensing solutions. To address this issue we present a proof-of-concept design and validation of a low-cost, lifetime-based oxygen sensing fiber. The sensor consists of readily-available off-the shelf components such as a microcontroller, a light-emitting diode (LED), an avalanche photodiode (APD), a temperature sensor, as well as a bright in-house developed porphyrin molecule. The device was calibrated using a benchtop setup and evaluated in three in vivo animal models. Our findings show that the new device design in combination with the bright porphyrin has the potential to be a useful and accurate tool for measuring [Formula: see text] in tissue, while also highlighting some of the limitations and challenges of oxygen measurements in this context.
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Affiliation(s)
- Lilian Witthauer
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
- Department of Diabetes, Endocrinology, Nutritional Medicine and Metabolism, Inselspital, Bern University Hospital and University of Bern, 3010, Bern, Switzerland
| | - Emmanuel Roussakis
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Juan Pedro Cascales
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Avery Goss
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Xiaolei Li
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA
| | - Alexis Cralley
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus, Aurora, CO, USA
| | - Dor Yoeli
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus, Aurora, CO, USA
| | - Hunter B Moore
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus, Aurora, CO, USA
| | - Zhaohui Wang
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus, Aurora, CO, USA
| | - Yong Wang
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus, Aurora, CO, USA
| | - Bing Li
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus, Aurora, CO, USA
| | - Christene A Huang
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus, Aurora, CO, USA
| | - Ernest E Moore
- Department of Surgery, University of Colorado Denver/Anschutz Medical Campus, Aurora, CO, USA
| | - Conor L Evans
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, 02129, USA.
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Nelskylä A, Humaloja J, Litonius E, Pekkarinen P, Babini G, Mäki-Aho TP, Heinonen JA, Skrifvars MB. The use of 100% compared to 50% oxygen during ineffective experimental cardiopulmonary resuscitation improves brain oxygenation. Resuscitation 2023; 182:109656. [PMID: 36470536 DOI: 10.1016/j.resuscitation.2022.11.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 11/17/2022] [Accepted: 11/26/2022] [Indexed: 12/07/2022]
Abstract
INTRODUCTION Perfusion pressure and chest compression quality are generally considered key determinants of brain oxygenation during cardiopulmonary resuscitation (CPR) and the impact of oxygen administration is less clear. We compared ventilation with 100% and 50% oxygen during ineffective manual chest compressions and hypothesized that 100% oxygen would improve brain oxygenation. METHODS Ventricular fibrillation (VF) was induced electrically in anaesthetized pigs and left untreated for 5 minutes, followed by randomization to ineffective manual CPR with ventilation of 50% or 100% oxygen. The first defibrillation was performed 10 minutes after induction of VF, and CPR continued with mechanical chest compressions (LUCAS2™) and defibrillation every 2 minutes until 36 minutes or return of spontaneous circulation (ROSC). Brain oxygenation was measured with near-infrared spectroscopy (rSO2) and invasive brain tissue oxygen (PbtO2) with a probe (NEUROVENT-PTO, RAUMEDIC) inserted into frontal brain tissue. Cerebral oxygenation was compared between groups with Mann-Whitney U tests and linear mixed models. RESULTS Twenty-eight pigs were included in the study: 14 subjects in each group. During ineffective chest compressions relative PbtO2 was higher in the group ventilated with 100% compared to 50% oxygen (5.2 mmHg [1.4-20.5] vs 2.2 [0.8-6.8], p = 0.001), but there was no difference in rSO2 (22% [16-28] vs 18 [15-25], p = 0.090). The use of 50% or 100% oxygen showed no difference in relative PbtO2 (p = 1.00) and rSO2 (p = 0.206) during mechanical CPR. CONCLUSIONS The use of 100% compared to 50% oxygen during ineffective manual CPR improved brain oxygenation measured invasively in brain tissue, but there was no difference in rSO2.
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Affiliation(s)
- Annika Nelskylä
- Department of Emergency Medicine and Services, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Jaana Humaloja
- Department of Emergency Medicine and Services, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Erik Litonius
- Division of Intensive Care, Department of Anaesthesiology, Intensive Care, and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Pirkka Pekkarinen
- Division of Intensive Care, Department of Anaesthesiology, Intensive Care, and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Giovanni Babini
- Department of Emergency Medicine and Services, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Tomi P Mäki-Aho
- Department of Emergency Medicine and Services, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Juho A Heinonen
- Division of Intensive Care, Department of Anaesthesiology, Intensive Care, and Pain Medicine, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Markus B Skrifvars
- Department of Emergency Medicine and Services, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.
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5
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Dong GJ, Yang J, Zhao X, Guo SB. Anisodamine hydrobromide ameliorates cardiac damage after resuscitation. Exp Ther Med 2022; 23:422. [PMID: 35601065 PMCID: PMC9117957 DOI: 10.3892/etm.2022.11349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 04/14/2022] [Indexed: 11/16/2022] Open
Abstract
The microcirculation is correlated with the prognosis of patients with cardiac arrest and changes after resuscitation. In the present study, the effects of anisodamine hydrobromide (AH) on microcirculation was investigated and its potential mechanisms were explored. A total of 24 pigs were randomly grouped into three groups (n=8): Sham, Saline and AH group. After pigs were anesthetized, intubated and mechanically ventilated, ventricular fibrillation was induced by electrical stimulation. After 8 min, cardiopulmonary resuscitation was given to the restoration of spontaneous circulation (ROSC). Arteriovenous blood was collected at baseline and 0, 1, 2, 4 and 6 h after ROSC to measure blood gas and cytokines. Perfused vessel density (PVD) and microvascular flow index (MFI) were measured to reflect the microcirculation. Continuous cardiac output and global ejection fraction were measured to indicate hemodynamics. Compared with Sham group, PVD and MFI in the intestines and the sublingual regions decreased significantly after resuscitation. The microcirculation recovered faster in the AH group than the SA group. The decrease of intestinal microcirculatory blood flow was closely related to the decrease of sublingual microcirculatory blood flow. The cardiac function was impaired after resuscitation, and a decrease of IFN-γ as well as IL-2 and an increase of IL-4 as well as IL-10 suggested the immune imbalance. The microcirculation changes in sublingual regions were closely related to the changes in intestines. AH could improve the immune imbalance after resuscitation and was beneficial to the recovery of cardiac function.
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Affiliation(s)
- Gui-Juan Dong
- Emergency Medicine Clinical Research Center, Beijing Chaoyang Hospital Affiliated to Capital Medical University, Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation, Beijing 100020, P.R. China
| | - Jun Yang
- Emergency Medicine Clinical Research Center, Beijing Chaoyang Hospital Affiliated to Capital Medical University, Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation, Beijing 100020, P.R. China
| | - Xin Zhao
- Emergency Medicine Clinical Research Center, Beijing Chaoyang Hospital Affiliated to Capital Medical University, Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation, Beijing 100020, P.R. China
| | - Shu-Bin Guo
- Emergency Medicine Clinical Research Center, Beijing Chaoyang Hospital Affiliated to Capital Medical University, Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation, Beijing 100020, P.R. China
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6
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Temporal changes in peripheral regional oxygen saturation associated with return of spontaneous circulation after out-of-hospital cardiac arrest: A prospective observational cohort study in Japan. Resuscitation 2022; 174:68-74. [DOI: 10.1016/j.resuscitation.2022.03.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 03/20/2022] [Accepted: 03/21/2022] [Indexed: 11/22/2022]
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7
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Mandigers L, Pooth JS, Wefers Bettink MA, den Uil CA, Damjanovic D, Mik EG, Brixius S, Gommers D, Trummer G, Dos Reis Miranda D. Monitoring Mitochondrial Partial Oxygen Pressure During Cardiac Arrest and Extracorporeal Cardiopulmonary Resuscitation. An Experimental Pilot Study in a Pig Model. Front Cardiovasc Med 2021; 8:754852. [PMID: 34760949 PMCID: PMC8572977 DOI: 10.3389/fcvm.2021.754852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 09/27/2021] [Indexed: 11/30/2022] Open
Abstract
Introduction: Ischemia and reperfusion are crucial in determining the outcome after cardiac arrest and can be influenced by extracorporeal cardiopulmonary resuscitation (ECPR). The effect of ECPR on the availability and level of oxygen in mitochondria remains unknown. The aim of this study was to find out if skin mitochondrial partial oxygen pressure (mitoPO2) measurements in cardiac arrest and ECPR are feasible and to investigate its course. Materials and Methods: We performed a feasibility test to determine if skin mitoPO2 measurements in a pig are possible. Next, we aimed to measure skin mitoPO2 in 10 experimental pigs. Measurements were performed using a cellular oxygen metabolism measurement monitor (COMET), at baseline, during cardiac arrest, and during ECPR using the controlled integrated resuscitation device (CIRD). Results: The feasibility test showed continuous mitoPO2 values. Nine experimental pigs could be measured. Measurements in six experimental pigs succeeded. Our results showed a delay until the initial spike of mitoPO2 after ECPR initiation in all six experimental tests. In two experiments (33%) mitoPO2 remained present after the initial spike. A correlation of mitoPO2 with mean arterial pressure (MAP) and arterial partial oxygen pressure measured by CIRD (CIRD-PaO2) seemed not present. One of the experimental pigs survived. Conclusions: This experimental pilot study shows that continuous measurements of skin mitoPO2 in pigs treated with ECPR are feasible. The delay in initial mitoPO2 and discrepancy of mitoPO2 and MAP in our small sample study could point to the possible value of additional measurements besides MAP to monitor the quality of tissue perfusion during cardiac arrest and ECPR.
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Affiliation(s)
- Loes Mandigers
- Department of Intensive Care, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Jan-Steffen Pooth
- Department of Cardiovascular Surgery, Heart Center Freiburg University, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Mark A Wefers Bettink
- Department of Anaesthesiology, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Corstiaan A den Uil
- Department of Intensive Care, Erasmus University Medical Center, Rotterdam, Netherlands.,Department of Cardiology, Erasmus University Medical Center, Rotterdam, Netherlands.,Department of Intensive Care, Maasstad Hospital, Rotterdam, Netherlands
| | - Domagoj Damjanovic
- Department of Cardiovascular Surgery, Heart Center Freiburg University, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Egbert G Mik
- Department of Anaesthesiology, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Sam Brixius
- Department of Cardiovascular Surgery, Heart Center Freiburg University, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Diederik Gommers
- Department of Intensive Care, Erasmus University Medical Center, Rotterdam, Netherlands
| | - Georg Trummer
- Department of Cardiovascular Surgery, Heart Center Freiburg University, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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8
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Zhao S, Yang Z, Sun P, Wu X, Tang W, Shao F, Tang Z. Conjunctival microcirculation is associated with cerebral cortex microcirculation in post-resuscitation mild hypothermia: A rat model. Microcirculation 2020; 27:e12604. [PMID: 31876330 DOI: 10.1111/micc.12604] [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] [Received: 09/26/2019] [Revised: 11/30/2019] [Accepted: 12/19/2019] [Indexed: 12/28/2022]
Abstract
OBJECTIVE This study aimed to compare the changes in sublingual and conjunctival microcirculation occurring with cerebral cortex microcirculation changes during mild hypothermia in a rat model of cardiac arrest. METHODS Twenty-four rats were randomized into mild hypothermia (M) or normothermia (C) groups. Ventricular fibrillation was electrically induced and left untreated for 8 minutes, followed by 8 minutes of cardiopulmonary resuscitation. The core temperature in group M reduced to 33 ± 0.5°C at 13 minutes after restoration of spontaneous circulation and was maintained for 8 hours. In group C, the core temperature was maintained at 37 ± 0.2°C. The hemodynamics and microcirculation in the sublingual region, bulbar conjunctiva, and cerebral cortex were measured at baseline and 1, 2, 3, 4, 6, and 8 hours after restoration of spontaneous circulation. RESULTS The M group showed significantly worse sublingual microcirculation at 6 hours post-resuscitation. However, microcirculation in the conjunctiva and cerebral cortex at 3 hours post-resuscitation were better in the M group. In the M group, microcirculation in the cerebral cortex was significantly correlated with that in the conjunctiva but not the sublingual microcirculation. CONCLUSIONS Changes in conjunctival microcirculation are closely related to cerebral cortex microcirculation during mild hypothermia, indicating that cerebral cortex microcirculation could be monitored by measuring conjunctival microcirculation.
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Affiliation(s)
- Shen Zhao
- Department of Emergency Medicine, Fujian Provincial Hospital, Fujian Institute of Emergency Medicine, Fujian Medical University, Fuzhou, China
| | - Zhengfei Yang
- Department of Emergency Medicine, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Peng Sun
- Department of Emergency Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaobo Wu
- Weil Institute of Emergency and Critical Care Research, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Wanchun Tang
- Weil Institute of Emergency and Critical Care Research, School of Medicine, Virginia Commonwealth University, Richmond, VA, USA
| | - Fei Shao
- Department of Emergency Medicine, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
| | - Ziren Tang
- Department of Emergency Medicine, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Cardiopulmonary Cerebral Resuscitation, Beijing Chao-Yang Hospital, Capital Medical University, Beijing, China
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9
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Hirai DM, Craig JC, Colburn TD, Eshima H, Kano Y, Musch TI, Poole DC. Skeletal muscle interstitial Po 2 kinetics during recovery from contractions. J Appl Physiol (1985) 2019; 127:930-939. [PMID: 31369325 DOI: 10.1152/japplphysiol.00297.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The oxygen partial pressure in the interstitial space (Po2 is) drives O2 into the myocyte via diffusion, thus supporting oxidative phosphorylation. Although crucial for metabolic recovery and the capacity to perform repetitive tasks, the time course of skeletal muscle Po2 is during recovery from contractions remains unknown. We tested the hypothesis that Po2 is would recover to resting values and display considerable on-off asymmetry (fast on-, slow off-kinetics), reflective of asymmetric capillary hemodynamics. Microvascular Po2 (Po2 mv) was also evaluated to test the hypothesis that a significant transcapillary gradient (ΔPo2 = Po2 mv - Po2 is) would be sustained during recovery. Po2 mv and Po2 is (expressed in mmHg) were determined via phosphorescence quenching in the exposed rat spinotrapezius muscle during and after submaximal twitch contractions (n = 12). Po2 is rose exponentially (P < 0.05) from end-contraction (11.1 ± 5.1), such that the end-recovery value (17.9 ± 7.9) was not different from resting Po2 is (18.5 ± 8.1; P > 0.05). Po2 is off-kinetics were slower than on-kinetics (mean response time: 53.1 ± 38.3 versus 18.5 ± 7.3 s; P < 0.05). A significant transcapillary ΔPo2 observed at end-contraction (16.6 ± 7.4) was maintained throughout recovery (end-recovery: 18.8 ± 9.6; P > 0.05). Consistent with our hypotheses, muscle Po2 is recovered to resting values with slower off-kinetics compared with the on-transient in line with the on-off asymmetry for capillary hemodynamics. Maintenance of a substantial transcapillary ΔPo2 during recovery supports that the microvascular-interstitium interface provides considerable resistance to O2 transport. As dictated by Fick's law (V̇o2 = Do2 × ΔPo2), modulation of O2 flux (V̇o2) during recovery must be achieved via corresponding changes in effective diffusing capacity (Do2; mainly capillary red blood cell hemodynamics and distribution) in the face of unaltered ΔPo2.NEW & NOTEWORTHY Capillary blood-myocyte O2 flux (V̇o2) is determined by effective diffusing capacity (Do2; mainly erythrocyte hemodynamics and distribution) and microvascular-interstitial Po2 gradients (ΔPo2 = Po2 mv - Po2 is). We show that Po2 is demonstrates on-off asymmetry consistent with Po2 mv and erythrocyte kinetics during metabolic transitions. A substantial transcapillary ΔPo2 was preserved during recovery from contractions, indicative of considerable resistance to O2 diffusion at the microvascular-interstitium interface. This reveals that effective Do2 declines in step with V̇o2 during recovery, as per Fick's law.
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Affiliation(s)
- Daniel M Hirai
- Department of Health and Kinesiology, Purdue University, West Lafayette, Indiana.,Department of Kinesiology, Kansas State University, Manhattan, Kansas.,Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Jesse C Craig
- Department of Kinesiology, Kansas State University, Manhattan, Kansas.,Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas.,Department of Internal Medicine, University of Utah, Salt Lake City, Utah.,Geriatric Research, Education, and Clinical Center, Veterans Affairs Medical Center, Salt Lake City, Utah
| | - Trenton D Colburn
- Department of Kinesiology, Kansas State University, Manhattan, Kansas.,Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - Hiroaki Eshima
- Department of Nutrition and Integrative Physiology, University of Utah, Salt Lake City, Utah
| | - Yutaka Kano
- Department of Engineering Science, University of Electro-Communications, Tokyo, Japan
| | - Timothy I Musch
- Department of Kinesiology, Kansas State University, Manhattan, Kansas.,Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
| | - David C Poole
- Department of Kinesiology, Kansas State University, Manhattan, Kansas.,Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas
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10
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Nosrati R, Lin S, Mohindra R, Ramadeen A, Toronov V, Dorian P. Study of the Effects of Epinephrine on Cerebral Oxygenation and Metabolism During Cardiac Arrest and Resuscitation by Hyperspectral Near-Infrared Spectroscopy. Crit Care Med 2019; 47:e349-e357. [PMID: 30747772 DOI: 10.1097/ccm.0000000000003640] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Epinephrine is routinely administered to sudden cardiac arrest patients during resuscitation, but the neurologic effects on patients treated with epinephrine are not well understood. This study aims to assess the cerebral oxygenation and metabolism during ventricular fibrillation cardiac arrest, cardiopulmonary resuscitation, and epinephrine administration. DESIGN To investigate the effects of equal dosages of IV epinephrine administrated following sudden cardiac arrest as a continuous infusion or successive boluses during cardiopulmonary resuscitation, we monitored cerebral oxygenation and metabolism using hyperspectral near-infrared spectroscopy. SETTINGS A randomized laboratory animal study. SUBJECTS Nine healthy pigs. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Our study showed that although continuous epinephrine administration had no significant impact on overall cerebral hemodynamics, epinephrine boluses transiently improved cerebral oxygenation (oxygenated hemoglobin) and metabolism (cytochrome c oxidase) by 15% ± 6.7% and 49% ± 18%, respectively (p < 0.05) compared with the baseline (untreated) ventricular fibrillation. Our results suggest that the effects of epinephrine diminish with successive boluses as the impact of the third bolus on brain oxygen metabolism was 24.6% ± 3.8% less than that of the first two boluses. CONCLUSIONS Epinephrine administration by bolus resulted in transient improvements in cerebral oxygenation and metabolism, whereas continuous epinephrine infusion did not, compared with placebo. Future studies are needed to evaluate and optimize the use of epinephrine in cardiac arrest resuscitation, particularly the dose, timing, and mode of administration.
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Affiliation(s)
- Reyhaneh Nosrati
- Department of Physics, Ryerson University, Toronto, ON, Canada
- Physical Sciences Platform, Sunnybrook Research Institute, Toronto, ON, Canada
| | - Steve Lin
- Department of Physics, Ryerson University, Toronto, ON, Canada
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
- Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada
| | - Rohit Mohindra
- Jewish General Hospital Department of Emergency Medicine, 3755 Ch de la Côte-Sainte-Catherine, Montreal, QC, Canada
- Department of Critical Care Research, McGill University, Montreal, QC, Canada
| | - Andrew Ramadeen
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
| | | | - Paul Dorian
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
- Department of Medicine, University of Toronto, Toronto, ON, Canada
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11
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Nguyen PL, Alreshaid L, Poblete RA, Konye G, Marehbian J, Sung G. Targeted Temperature Management and Multimodality Monitoring of Comatose Patients After Cardiac Arrest. Front Neurol 2018; 9:768. [PMID: 30254606 PMCID: PMC6141756 DOI: 10.3389/fneur.2018.00768] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 08/24/2018] [Indexed: 01/14/2023] Open
Abstract
Out-of-hospital cardiac arrest (CA) remains a leading cause of sudden morbidity and mortality; however, outcomes have continued to improve in the era of targeted temperature management (TTM). In this review, we highlight the clinical use of TTM, and provide an updated summary of multimodality monitoring possible in a modern ICU. TTM is neuroprotective for survivors of CA by inhibiting multiple pathophysiologic processes caused by anoxic brain injury, with a final common pathway of neuronal death. Current guidelines recommend the use of TTM for out-of-hospital CA survivors who present with a shockable rhythm. Further studies are being completed to determine the optimal timing, depth and duration of hypothermia to optimize patient outcomes. Although a multidisciplinary approach is necessary in the CA population, neurologists and neurointensivists are central in selecting TTM candidates and guiding patient care and prognostic evaluation. Established prognostic tools include clinal exam, SSEP, EEG and MR imaging, while functional MRI and invasive monitoring is not validated to improve outcomes in CA or aid in prognosis. We recommend that an evidence-based TTM and prognostication algorithm be locally implemented, based on each institution's resources and limitations. Given the high incidence of CA and difficulty in predicting outcomes, further study is urgently needed to determine the utility of more recent multimodality devices and studies.
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Affiliation(s)
- Peggy L Nguyen
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Laith Alreshaid
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Roy A Poblete
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Geoffrey Konye
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Jonathan Marehbian
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Gene Sung
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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12
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Hirai DM, Craig JC, Colburn TD, Eshima H, Kano Y, Sexton WL, Musch TI, Poole DC. Skeletal muscle microvascular and interstitial PO2 from rest to contractions. J Physiol 2018; 596:869-883. [PMID: 29288568 DOI: 10.1113/jp275170] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 12/01/2017] [Indexed: 01/21/2023] Open
Abstract
KEY POINTS Oxygen pressure gradients across the microvascular walls are essential for oxygen diffusion from blood to tissue cells. At any given flux, the magnitude of these transmural gradients is proportional to the local resistance. The greatest resistance to oxygen transport into skeletal muscle is considered to reside in the short distance between red blood cells and myocytes. Although crucial to oxygen transport, little is known about transmural pressure gradients within skeletal muscle during contractions. We evaluated oxygen pressures within both the skeletal muscle microvascular and interstitial spaces to determine transmural gradients during the rest-contraction transient in anaesthetized rats. The significant transmural gradient observed at rest was sustained during submaximal muscle contractions. Our findings support that the blood-myocyte interface provides substantial resistance to oxygen diffusion at rest and during contractions and suggest that modulations in microvascular haemodynamics and red blood cell distribution constitute primary mechanisms driving increased transmural oxygen flux with contractions. ABSTRACT Oxygen pressure (PO2) gradients across the blood-myocyte interface are required for diffusive O2 transport, thereby supporting oxidative metabolism. The greatest resistance to O2 flux into skeletal muscle is considered to reside between the erythrocyte surface and adjacent sarcolemma, although this has not been measured during contractions. We tested the hypothesis that O2 gradients between skeletal muscle microvascular (PO2 mv ) and interstitial (PO2 is ) spaces would be present at rest and maintained or increased during contractions. PO2 mv and PO2 is were determined via phosphorescence quenching (Oxyphor probes G2 and G4, respectively) in the exposed rat spinotrapezius during the rest-contraction transient (1 Hz, 6 V; n = 8). PO2 mv was higher than PO2 is in all instances from rest (34.9 ± 6.0 versus 15.7 ± 6.4) to contractions (28.4 ± 5.3 versus 10.6 ± 5.2 mmHg, respectively) such that the mean PO2 gradient throughout the transient was 16.9 ± 6.6 mmHg (P < 0.05 for all). No differences in the amplitude of PO2 fall with contractions were observed between the microvasculature and interstitium (10.9 ± 2.3 versus 9.0 ± 3.5 mmHg, respectively; P > 0.05). However, the speed of the PO2 is fall during contractions was slower than that of PO2 mv (time constant: 12.8 ± 4.7 versus 9.0 ± 5.1 s, respectively; P < 0.05). Consistent with our hypothesis, a significant transmural gradient was sustained (but not increased) from rest to contractions. This supports that the blood-myocyte interface is the site of a substantial PO2 gradient driving O2 diffusion during metabolic transients. Based on Fick's law, elevated O2 flux with contractions must thus rely primarily on modulations in effective diffusing capacity (mainly erythrocyte haemodynamics and distribution) as the PO2 gradient is not increased.
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Affiliation(s)
- Daniel M Hirai
- Departments of Anatomy & Physiology, Kinesiology, Kansas State University, Manhattan, KS, USA
| | - Jesse C Craig
- Departments of Anatomy & Physiology, Kinesiology, Kansas State University, Manhattan, KS, USA
| | - Trenton D Colburn
- Departments of Anatomy & Physiology, Kinesiology, Kansas State University, Manhattan, KS, USA
| | - Hiroaki Eshima
- Department of Engineering Science, University of Electro-Communications, Tokyo, Japan
| | - Yutaka Kano
- Department of Engineering Science, University of Electro-Communications, Tokyo, Japan
| | - William L Sexton
- Department of Physiology, A.T. Still University of Health Sciences, Kirksville, MO, USA
| | - Timothy I Musch
- Departments of Anatomy & Physiology, Kinesiology, Kansas State University, Manhattan, KS, USA
| | - David C Poole
- Departments of Anatomy & Physiology, Kinesiology, Kansas State University, Manhattan, KS, USA
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13
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Solomatina AI, Su SH, Lukina MM, Dudenkova VV, Shcheslavskiy VI, Wu CH, Chelushkin PS, Chou PT, Koshevoy IO, Tunik SP. Water-soluble cyclometalated platinum(ii) and iridium(iii) complexes: synthesis, tuning of the photophysical properties, and in vitro and in vivo phosphorescence lifetime imaging. RSC Adv 2018; 8:17224-17236. [PMID: 35539280 PMCID: PMC9080394 DOI: 10.1039/c8ra02742k] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 04/29/2018] [Indexed: 12/12/2022] Open
Abstract
This paper presents synthesis and photophysical investigation of cyclometalated water-soluble Pt(ii) and Ir(iii) complexes containing auxiliary sulfonated diphosphine (bis(diphenylphosphino)benzene (dppb), P^P*) ligand. The complexes demonstrate considerable variations in excitation (extending up to 450 nm) and emission bands (with maxima ranging from ca. 450 to ca. 650 nm), as well as in the sensitivity of excited state lifetimes to molecular oxygen (from almost negligible to more than 4-fold increase in degassed solution). Moreover, all the complexes possess high two-photon absorption cross sections (400–500 GM for Pt complexes, and 600–700 GM for Ir complexes). Despite their negative net charge, all the complexes demonstrate good uptake by HeLa cells and low cytotoxicity within the concentration and time ranges suitable for two-photon phosphorescence lifetime (PLIM) microscopy. The most promising complex, [(ppy)2Ir(sulfo-dppb)] (Ir1*), upon incubation in HeLa cells demonstrates two-fold lifetime variations under normal and nitrogen atmosphere, correspondingly. Moreover, its in vivo evaluation in athymic nude mice bearing HeLa tumors did not reveal acute toxicity upon both intravenous and topical injections. Finally, Ir1* demonstrated statistically significant difference in lifetimes between normal tissue (muscle) and tumor in macroscopic in vivo PLIM imaging. Novel water-soluble iridium complexes with sulfonated diphosphine allow in vitro and in vivo lifetime hypoxia imaging.![]()
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Affiliation(s)
| | - Shih-Hao Su
- Department of Chemistry
- National Taiwan University
- Taipei
- Republic of China
| | - Maria M. Lukina
- Institute of Biomedical Technologies
- Privolzhskiy Research Medical University
- Nizhny Novgorod 603005
- Russia
| | - Varvara V. Dudenkova
- Institute of Biomedical Technologies
- Privolzhskiy Research Medical University
- Nizhny Novgorod 603005
- Russia
| | | | - Cheng-Ham Wu
- Department of Chemistry
- National Taiwan University
- Taipei
- Republic of China
| | | | - Pi-Tai Chou
- Department of Chemistry
- National Taiwan University
- Taipei
- Republic of China
| | - Igor O. Koshevoy
- Department of Chemistry
- University of Eastern Finland
- 80101 Joensuu
- Finland
| | - Sergey P. Tunik
- St. Petersburg State University
- Institute of Chemistry
- St. Petersburg
- Russia
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14
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Nelskylä A, Nurmi J, Jousi M, Schramko A, Mervaala E, Ristagno G, Skrifvars MB. The effect of 50% compared to 100% inspired oxygen fraction on brain oxygenation and post cardiac arrest mitochondrial function in experimental cardiac arrest. Resuscitation 2017; 116:1-7. [DOI: 10.1016/j.resuscitation.2017.04.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 03/27/2017] [Accepted: 04/18/2017] [Indexed: 12/17/2022]
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15
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Nosrati R, Lin S, Ramadeen A, Monjazebi D, Dorian P, Toronov V. Cerebral Hemodynamics and Metabolism During Cardiac Arrest and Cardiopulmonary Resuscitation Using Hyperspectral Near Infrared Spectroscopy. Circ J 2017; 81:879-887. [PMID: 28302943 DOI: 10.1253/circj.cj-16-1225] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Maintaining cerebral oxygen delivery and metabolism during cardiac arrest (CA) through resuscitation is essential to improve the survival rate while avoiding brain injury. The effect of CA and cardiopulmonary resuscitation (CPR) on cerebral and muscle oxygen delivery and metabolism is not clearly quantified.Methods and Results:A novel hyperspectral near-infrared spectroscopy (hNIRS) technique was developed and evaluated to measure cerebral oxygen delivery and aerobic metabolism during ventricular fibrillation (VF) CA and CPR in 14 pigs. The hNIRS parameters were measured simultaneously on the dura and skull to investigate the validity of non-invasive hNIRS measurements. In addition, we compared the hNIRS data collected simultaneously on the brain and muscle. Following VF induction, oxygenated hemoglobin (HbO2) declined with a 9.9 s delay and then cytochrome-c-oxidase (Cyt-ox) decreased on average 4.4 s later (P<0.05). CPR improved cerebral metabolism, which was reflected by an average 0.4 μmol/L increase in Cyt-ox, but had no significant effect on HbO2, deoxygenated hemoglobin (HHb) and tissue oxygen saturation (tSO2). Cyt-ox had greater correlation with HHb than HbO2. Muscle metabolism during VF and CPR was significantly different from that of the brain. The total hemoglobin concentration (in the brain only) increased after ~200 s of untreated CA, which is most likely driven by cerebral autoregulation through vasodilation. CONCLUSIONS Overall, hNIRS showed consistent measurements of hemodynamics and metabolism during CA and CPR.
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Affiliation(s)
- Reyhaneh Nosrati
- Department of Physics, Ryerson University.,Medical Physics, Sunnybrook Health Sciences Centre
| | - Steve Lin
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital.,Department of Medicine, University of Toronto
| | - Andrew Ramadeen
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital
| | | | - Paul Dorian
- Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital.,Department of Medicine, University of Toronto
| | - Vladislav Toronov
- Department of Physics, Ryerson University.,Keenan Research Centre, Li Ka Shing Knowledge Institute, St. Michael's Hospital
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16
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Cahill LS, Gazdzinski LM, Tsui AK, Zhou YQ, Portnoy S, Liu E, Mazer CD, Hare GM, Kassner A, Sled JG. Functional and anatomical evidence of cerebral tissue hypoxia in young sickle cell anemia mice. J Cereb Blood Flow Metab 2017; 37:994-1005. [PMID: 27165012 PMCID: PMC5363475 DOI: 10.1177/0271678x16649194] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Cerebral ischemia is a significant source of morbidity in children with sickle cell anemia; however, the mechanism of injury is poorly understood. Increased cerebral blood flow and low hemoglobin levels in children with sickle cell anemia are associated with increased stroke risk, suggesting that anemia-induced tissue hypoxia may be an important factor contributing to subsequent morbidity. To better understand the pathophysiology of brain injury, brain physiology and morphology were characterized in a transgenic mouse model, the Townes sickle cell model. Relative to age-matched controls, sickle cell anemia mice demonstrated: (1) decreased brain tissue pO2 and increased expression of hypoxia signaling protein in the perivascular regions of the cerebral cortex; (2) elevated basal cerebral blood flow , consistent with adaptation to anemia-induced tissue hypoxia; (3) significant reduction in cerebrovascular blood flow reactivity to a hypercapnic challenge; (4) increased diameter of the carotid artery; and (5) significant volume changes in white and gray matter regions in the brain, as assessed by ex vivo magnetic resonance imaging. Collectively, these findings support the hypothesis that brain tissue hypoxia contributes to adaptive physiological and anatomic changes in Townes sickle cell mice. These findings may help define the pathophysiology for stroke in children with sickle cell anemia.
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Affiliation(s)
- Lindsay S Cahill
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Lisa M Gazdzinski
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Albert Ky Tsui
- 2 Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Anesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Yu-Qing Zhou
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Sharon Portnoy
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Elaine Liu
- 2 Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Anesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada
| | - C David Mazer
- 2 Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Anesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,3 Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Gregory Mt Hare
- 2 Keenan Research Centre for Biomedical Science and Li Ka Shing Knowledge Institute of St. Michael's Hospital, Department of Anesthesia, St. Michael's Hospital, University of Toronto, Toronto, Ontario, Canada.,3 Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Andrea Kassner
- 4 Department of Medical Imaging, University of Toronto and The Hospital for Sick Children, Toronto, Ontario, Canada
| | - John G Sled
- 1 Mouse Imaging Centre, The Hospital for Sick Children, Toronto, Ontario, Canada.,5 Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
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17
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Oxygen imaging of living cells and tissues using luminescent molecular probes. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2017. [DOI: 10.1016/j.jphotochemrev.2017.01.001] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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18
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Experimental assessment of oxygen homeostasis during acute hemodilution: the integrated role of hemoglobin concentration and blood pressure. Intensive Care Med Exp 2017; 5:12. [PMID: 28251580 PMCID: PMC5332316 DOI: 10.1186/s40635-017-0125-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 02/21/2017] [Indexed: 11/12/2022] Open
Abstract
Background Low hemoglobin concentration (Hb) and low mean arterial blood pressure (MAP) impact outcomes in critically ill patients. We utilized an experimental model of “normotensive” vs. “hypotensive” acute hemodilutional anemia to test whether optimal tissue perfusion is dependent on both Hb and MAP during acute blood loss and fluid resuscitation, and to assess the value of direct measurements of the partial pressure of oxygen in tissue (PtO2). Methods Twenty-nine anesthetized rats underwent 40% isovolemic hemodilution (1:1) (or sham-hemodilution control, n = 4) with either hydroxyethyl starch (HES) (n = 14, normotensive anemia) or saline (n = 11, hypotensive anemia) to reach a target Hb value near 70 g/L. The partial pressure of oxygen in the brain and skeletal muscle tissue (PtO2) were measured by phosphorescence quenching of oxygen using G4 Oxyphor. Mean arterial pressure (MAP), heart rate, temperature, arterial and venous co-oximetry, blood gases, and lactate were assessed at baseline and for 60 min after hemodilution. Cardiac output (CO) was measured at baseline and immediately after hemodilution. Data were analyzed by repeated measures two-way ANOVA. Results Following “normotensive” hemodilution with HES, Hb was reduced to 66 ± 6 g/L, CO increased (p < 0.05), and MAP was maintained. These conditions resulted in a reduction in brain PtO2 (22.1 ± 5.6 mmHg to 17.5 ± 4.4 mmHg, p < 0.05), unchanged muscle PO2, and an increase in venous oxygen extraction. Following “hypotensive” hemodilution with saline, Hb was reduced to 79 ± 5 g/L and both CO and MAP were decreased (P < 0.05). These conditions resulted in a more severe reduction in brain PtO2 (23.2 ± 8.2 to 10.7 ± 3.6 mmHg (p < 0.05), a reduction in muscle PtO2 (44.5 ± 11.0 to 19.9 ± 12.4 mmHg, p < 0.05), a further increase in venous oxygen extraction, and a threefold increase in systemic lactate levels (p < 0.05). Conclusions Acute normotensive anemia (HES hemodilution) was associated with a subtle decrease in brain tissue PtO2 without clear evidence of global tissue hypoperfusion. By contrast, acute hypotensive anemia (saline hemodilution) resulted in a profound decrease in both brain and muscle tissue PtO2 and evidence of inadequate global perfusion (lactic acidosis). These data emphasize the importance of maintaining CO and MAP to ensure adequacy of vital organ oxygen delivery during acute anemia. Improved methods of assessing PtO2 may provide an earlier warning signal of vital organ hypoperfusion.
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19
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Mullah SH, Abutarboush R, Moon-Massat PF, Saha BK, Haque A, Walker PB, Auker CR, Arnaud FG, McCarron RM, Scultetus AH. Sanguinate's effect on pial arterioles in healthy rats and cerebral oxygen tension after controlled cortical impact. Microvasc Res 2016; 107:83-90. [PMID: 27287870 DOI: 10.1016/j.mvr.2016.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 05/23/2016] [Accepted: 06/06/2016] [Indexed: 01/18/2023]
Abstract
Sanguinate, a polyethylene glycol-conjugated carboxyhemoglobin, was investigated for cerebral vasoactivity in healthy male Sprague-Dawley rats (Study 1) and for its ability to increase brain tissue oxygen pressure (PbtO2) after controlled cortical impact (CCI) - traumatic brain injury (TBI) (Study 2). In both studies ketamine-acepromazine anesthetized rats were ventilated with 40% O2. In Study 1, a cranial window was used to measure the diameters of medium - (50-100μm) and small-sized (<50μm) pial arterioles before and after four serial infusions of Sanguinate (8mL/kg/h, cumulative 16mL/kg IV), volume-matched Hextend, or normal saline. In Study 2, PbtO2 was measured using a phosphorescence quenching method before TBI, 15min after TBI (T15) and then every 10min thereafter for 155min. At T15, rats received either 8mL/kg IV Sanguinate (40mL/kg/h) or no treatment (saline, 4mL/kg/h). Results showed: 1) in healthy rats, percentage changes in pial arteriole diameter were the same among the groups, 2) in TBI rats, PbtO2 decreased from 36.5±3.9mmHg to 19.8±3.0mmHg at T15 in both groups after TBI and did not recover in either group for the rest of the study, and 3) MAP increased 16±4mmHg and 36±5mmHg after Sanguinate in healthy and TBI rats, respectively, while MAP was unchanged in control groups. In conclusion, Sanguinate did not cause vasoconstriction in the cerebral pial arterioles of healthy rats but it also did not acutely increase PbtO2 when administered after TBI. Sanguinate was associated with an increase in MAP in both studies.
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Affiliation(s)
- Saad H Mullah
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Rania Abutarboush
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Paula F Moon-Massat
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Biswajit K Saha
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Ashraful Haque
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Peter B Walker
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Charles R Auker
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA.
| | - Francoise G Arnaud
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA; Uniformed Services University of the Health Sciences, Department of Surgery, Bethesda, MD 20814, USA.
| | - Richard M McCarron
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA; Uniformed Services University of the Health Sciences, Department of Surgery, Bethesda, MD 20814, USA.
| | - Anke H Scultetus
- Naval Medical Research Center, NeuroTrauma Department, 503 Robert Grant Avenue Silver Spring, MD 20910, USA; Uniformed Services University of the Health Sciences, Department of Surgery, Bethesda, MD 20814, USA.
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20
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Perfluorocarbon NVX-108 increased cerebral oxygen tension after traumatic brain injury in rats. Brain Res 2016; 1634:132-139. [PMID: 26794250 DOI: 10.1016/j.brainres.2016.01.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 12/23/2015] [Accepted: 01/08/2016] [Indexed: 11/23/2022]
Abstract
BACKGROUND Hypoxia is a critical secondary injury mechanism in traumatic brain injury (TBI), and early intervention to alleviate post-TBI hypoxia may be beneficial. NVX-108, a dodecafluoropentane perfluorocarbon, was screened for its ability to increase brain tissue oxygen tension (PbtO2) when administered soon after TBI. METHODS Ketamine-acepromazine anesthetized rats ventilated with 40% oxygen underwent moderate controlled cortical impact (CCI)-TBI at time 0 (T0). Rats received either no treatment (NON, n=8) or 0.5 ml/kg intravenous (IV) NVX-108 (NVX, n=9) at T15 (15 min after TBI) and T75. RESULTS Baseline cortical PbtO2 was 28±3 mm Hg and CCI-TBI resulted in a 46±6% reduction in PbtO2 at T15 (P<0.001). Significant differences in time-group interactions (P=0.013) were found when comparing either absolute or percentage change of PbtO2 to post-injury (mixed-model ANOVA) suggesting that administration of NVX-108 increased PbtO2 above injury levels while it remained depressed in the NON group. Specifically in the NVX group, PbtO2 increased to a peak 143% of T15 (P=0.02) 60 min after completion of NVX-108 injection (T135). Systemic blood pressure was not different between the groups. CONCLUSION NVX-108 caused an increase in PbtO2 following CCI-TBI in rats and should be evaluated further as a possible immediate treatment for TBI.
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21
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Zhdanov AV, Golubeva AV, Okkelman IA, Cryan JF, Papkovsky DB. Imaging of oxygen gradients in giant umbrella cells: an ex vivo PLIM study. Am J Physiol Cell Physiol 2015; 309:C501-9. [DOI: 10.1152/ajpcell.00121.2015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Accepted: 08/03/2015] [Indexed: 12/29/2022]
Abstract
O2 plays a pivotal role in aerobic metabolism and regulation of cell and tissue function. Local differences and fluctuations in tissue O2 levels are well documented; however, the physiological significance of O2 microgradients, particularly at the subcellular level, remains poorly understood. Using the cell-penetrating phosphorescent O2 probe Pt-Glc and confocal fluorescence microscopy, we visualized O2 distribution in individual giant (>100-μm) umbrella cells located superficially in the urinary bladder epithelium. We optimized conditions for in vivo phosphorescent staining of the inner surface of the mouse bladder and subsequent ex vivo analysis of excised live tissue. Imaging experiments revealed significant (≤85 μM) and heterogeneous deoxygenation within respiring umbrella cells, with radial O2 gradients of up to 40 μM across the cell, or ∼0.6 μM/μm. Deeply deoxygenated (5–15 μM O2) regions were seen to correspond to the areas enriched with polarized mitochondria. Pharmacological activation of mitochondrial respiration decreased oxygenation and O2 gradients in umbrella cells, while inhibition with antimycin A dissipated the gradients and caused gradual reoxygenation of the tissue to ambient levels. Detailed three-dimensional maps of O2 distribution potentially can be used for the modeling of intracellular O2-dependent enzymatic reactions and downstream processes, such as hypoxia-inducible factor signaling. Further ex vivo and in vivo studies on intracellular and tissue O2 gradients using confocal imaging can shed light on the molecular mechanisms regulating O2-dependent (patho)physiological processes in the bladder and other tissues.
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Affiliation(s)
- A. V. Zhdanov
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | - A. V. Golubeva
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland; and
| | - I. A. Okkelman
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
| | - J. F. Cryan
- Alimentary Pharmabiotic Centre, University College Cork, Cork, Ireland; and
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - D. B. Papkovsky
- School of Biochemistry and Cell Biology, University College Cork, Cork, Ireland
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22
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De Santis V, Singer M. Tissue oxygen tension monitoring of organ perfusion: rationale, methodologies, and literature review. Br J Anaesth 2015. [PMID: 26198717 DOI: 10.1093/bja/aev162] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Tissue oxygen tension is the partial pressure of oxygen within the interstitial space of an organ bed. As it represents the balance between local oxygen delivery and consumption at any given time, it offers a ready monitoring capability to assess the adequacy of tissue perfusion relative to local demands. This review covers the various methodologies used to measure tissue oxygen tension, describes the underlying physiological and pathophysiological principles, and summarizes human and laboratory data published to date.
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Affiliation(s)
- V De Santis
- Bloomsbury Institute of Intensive Care Medicine, Division of Medicine, University College London, Cruciform Building, Gower Street, London WC1E 6BT, UK
| | - M Singer
- Bloomsbury Institute of Intensive Care Medicine, Division of Medicine, University College London, Cruciform Building, Gower Street, London WC1E 6BT, UK
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23
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Huang SH, Yu CH, Chien YL. Light-addressable measurement of in vivo tissue oxygenation in an unanesthetized zebrafish embryo via phase-based phosphorescence lifetime detection. SENSORS 2015; 15:8146-62. [PMID: 25856326 PMCID: PMC4431297 DOI: 10.3390/s150408146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 02/25/2015] [Accepted: 03/31/2015] [Indexed: 01/04/2023]
Abstract
We have developed a digital light modulation system that utilizes a modified commercial projector equipped with a laser diode as a light source for quantitative measurements of in vivo tissue oxygenation in an unanesthetized zebrafish embryo via phase-based phosphorescence lifetime detection. The oxygen-sensitive phosphorescent probe (Oxyphor G4) was first inoculated into the bloodstream of 48 h post-fertilization (48 hpf) zebrafish embryos via the circulation valley to rapidly disperse probes throughout the embryo. The unanesthetized zebrafish embryo was introduced into the microfluidic device and immobilized on its lateral side by using a pneumatically actuated membrane. By controlling the illumination pattern on the digital micromirror device in the projector, the modulated excitation light can be spatially projected to illuminate arbitrarily-shaped regions of tissue of interest for in vivo oxygen measurements. We have successfully measured in vivo oxygen changes in the cardiac region and cardinal vein of a 48 hpf zebrafish embryo that experience hypoxia and subsequent normoxic conditions. Our proposed platform provides the potential for the real-time investigation of oxygen distribution in tissue microvasculature that relates to physiological stimulation and diseases in a developing organism.
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Affiliation(s)
- Shih-Hao Huang
- Department of Mechanical and Mechatronic Engineering, National Taiwan Ocean University, Keelung 202-24, Taiwan.
- Center for Marine Mechatronic Systems, CMMS, National Taiwan Ocean University, Keelung 202-24, Taiwan.
| | - Chu-Hung Yu
- Department of Mechanical and Mechatronic Engineering, National Taiwan Ocean University, Keelung 202-24, Taiwan.
| | - Yi-Lung Chien
- Department of Mechanical and Mechatronic Engineering, National Taiwan Ocean University, Keelung 202-24, Taiwan.
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24
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Roussakis E, Spencer JA, Lin CP, Vinogradov SA. Two-photon antenna-core oxygen probe with enhanced performance. Anal Chem 2014; 86:5937-45. [PMID: 24848643 PMCID: PMC4066907 DOI: 10.1021/ac501028m] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Recent development of two-photon phosphorescence lifetime microscopy (2PLM) of oxygen enabled first noninvasive high-resolution measurements of tissue oxygenation in vivo in 3D, providing valuable physiological information. The so far developed two-photon-enhanced phosphorescent probes comprise antenna-core constructs, in which two-photon absorbing chromophores (antenna) capture and channel excitation energy to a phosphorescent core (metalloporphyrin) via intramolecular excitation energy transfer (EET). These probes allowed demonstration of the methods' potential; however, they suffer from a number of limitations, such as partial loss of emissivity to competing triplet state deactivation pathways (e.g., electron transfer) and suboptimal sensitivity to oxygen, thereby limiting spatial and temporal resolution of the method. Here we present a new probe, PtTCHP-C307, designed to overcome these limitations. The key improvements include significant increase in the phosphorescence quantum yield, higher efficiency of the antenna-core energy transfer, minimized quenching of the phosphorescence by electron transfer and increased signal dynamic range. For the same excitation flux, the new probe is able to produce up to 6-fold higher signal output than previously reported molecules. Performance of PtTCHP-C307 was demonstrated in vivo in pO2 measurements through the intact mouse skull into the bone marrow, where all blood cells are made from hematopoietic stem cells.
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Affiliation(s)
- Emmanuel Roussakis
- Department of Biochemistry and Biophysics, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States
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25
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The impact of oxygen and carbon dioxide management on outcome after cardiac arrest. Curr Opin Crit Care 2014; 20:266-72. [DOI: 10.1097/mcc.0000000000000084] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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26
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Qian J, Yang Z, Cahoon J, Xu J, Zhu C, Yang M, Hu X, Sun S, Tang W. Post-resuscitation intestinal microcirculation: its relationship with sublingual microcirculation and the severity of post-resuscitation syndrome. Resuscitation 2014; 85:833-9. [PMID: 24594091 DOI: 10.1016/j.resuscitation.2014.02.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 01/10/2014] [Accepted: 02/20/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Post-resuscitation syndrome has been recognized as one of the major causes of the poor outcomes of cardiopulmonary resuscitation. The aims of this study were to investigate the intestinal microcirculatory changes following cardiopulmonary resuscitation and relate those changes to sublingual microcirculation and the severity of post-resuscitation syndrome as measured by myocardial function and serum inflammatory cytokine levels. METHODS Twenty-five rats were randomized into three groups: (1) short duration of cardiac arrest (n=10): ventricular fibrillation (VF) was untreated for 4 min prior to 6 min of cardiopulmonary resuscitation (CPR); (2) long duration of cardiac arrest (n=10): VF was untreated for 8 min followed by 8 min of CPR; (3) sham control group (n=5): a sham operation was performed without VF induction and CPR. Intestinal and sublingual microcirculatory blood flow was visualized by a sidestream dark-field (SDF) imaging device at baseline and 1, 2, 4, 6, 8 h post-resuscitation. Myocardial function was measured by echocardiography and serum cytokine levels (TNF-α and IL-6) were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS Both intestinal and sublingual microcirculatory blood flow decreased significantly with increasing duration of cardiac arrest and resuscitation. The decreases in intestinal microcirculatory blood flow were closely correlated with the reductions of sublingual microcirculatory blood flow (perfused small vessels density: r=0.772, p<0.01; microcirculatory flow index: r=0.821, p<0.01). The decreased microcirculatory blood flow was closely correlated with weakened myocardial function and elevated inflammatory cytokine levels. CONCLUSIONS The severity of post-resuscitation intestinal microcirculatory dysfunction is closely correlated with that of myocardial function and inflammatory cytokine levels. The measurement of sublingual microcirculation reflects changes of intestinal microcirculation and may therefore provide a new option for post-resuscitation monitoring.
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Affiliation(s)
- Jie Qian
- Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States; Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
| | - Zhengfei Yang
- Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States.
| | - Jena Cahoon
- Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States.
| | - Jiefeng Xu
- Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States.
| | - Changqing Zhu
- Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
| | - Min Yang
- Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States.
| | - Xianwen Hu
- Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States.
| | - Shijie Sun
- Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States; Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States.
| | - Wanchun Tang
- Weil Institute of Critical Care Medicine, Rancho Mirage, CA, United States; Keck School of Medicine of the University of Southern California, Los Angeles, CA, United States.
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27
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Johnstone C. Brain oxygenation - does raised intracranial pressure play a role? Anaesthesia 2013; 68:1282. [DOI: 10.1111/anae.12470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- C. Johnstone
- Liverpool Heart and Chest Hospital; Liverpool UK
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