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Fushimi M, Takeda Y, Mizoue R, Sato S, Kawase H, Takasugi Y, Murai S, Morimatsu H. Cardiopulmonary Resuscitation May Not Stop Glutamate Release in the Cerebral Cortex. J Neurosurg Anesthesiol 2023; 35:341-346. [PMID: 35275099 DOI: 10.1097/ana.0000000000000838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 01/28/2022] [Indexed: 11/27/2022]
Abstract
BACKGROUND Cardiopulmonary resuscitation (CPR) may not be sufficient to halt the progression of brain damage. Using extracellular glutamate concentration as a marker for neuronal damage, we quantitatively evaluated the degree of brain damage during resuscitation without return of spontaneous circulation. MATERIALS AND METHODS Extracellular cerebral glutamate concentration was measured with a microdialysis probe every 2 minutes for 40 minutes after electrical stimulation-induced cardiac arrest without return of spontaneous circulation in Sprague-Dawley rats. The rats were divided into 3 groups (7 per group) according to the treatment received during the 40 minutes observation period: mechanical ventilation without chest compression (group V); mechanical ventilation and chest compression (group VC) and; ventilation, chest compression and brain hypothermia (group VCH). Chest compression (20 min) and hypothermia (40 min) were initiated 6 minutes after the onset of cardiac arrest. RESULTS Glutamate concentration increased in all groups after cardiac arrest. Although after the onset of chest compression, glutamate concentration showed a significant difference at 2 min and reached the maximum at 6 min (VC group; 284±48 μmol/L vs. V group 398±126 μmol/L, P =0.003), there was no difference toward the end of chest compression (513±61 μmol/L vs. 588±103 μmol/L, P =0.051). In the VCH group, the initial increase in glutamate concentration was suddenly suppressed 2 minutes after the onset of brain hypothermia. CONCLUSIONS CPR alone reduced the progression of brain damage for a limited period but CPR in combination with brain cooling strongly suppressed increases in glutamate levels.
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Affiliation(s)
| | - Yoshimasa Takeda
- Department of Anesthesiology, Faculty of Medicine, Toho University, Tokyo, Japan
| | | | | | | | - Yuji Takasugi
- Neurological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama
| | - Satoshi Murai
- Neurological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama
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Depolarization time and extracellular glutamate levels aggravate ultraearly brain injury after subarachnoid hemorrhage. Sci Rep 2022; 12:10256. [PMID: 35715559 PMCID: PMC9205962 DOI: 10.1038/s41598-022-14360-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 06/06/2022] [Indexed: 11/15/2022] Open
Abstract
Early brain injury after aneurysmal subarachnoid hemorrhage (SAH) worsens the neurological outcome. We hypothesize that a longer duration of depolarization and excessive release of glutamate aggravate neurological outcomes after SAH, and that brain hypothermia can accelerate repolarization and inhibit the excessive release of extracellular glutamate and subsequent neuronal damage. So, we investigated the influence of depolarization time and extracellular glutamate levels on the neurological outcome in the ultra-early phase of SAH using a rat injection model as Experiment 1 and then evaluated the efficacy of brain hypothermia targeting ultra-early brain injury as Experiment 2. Dynamic changes in membrane potentials, intracranial pressure, cerebral perfusion pressure, cerebral blood flow, and extracellular glutamate levels were observed within 30 min after SAH. A prolonged duration of depolarization correlated with peak extracellular glutamate levels, and these two factors worsened the neuronal injury. Under brain hypothermia using pharyngeal cooling after SAH, cerebral perfusion pressure in the hypothermia group recovered earlier than that in the normothermia group. Extracellular glutamate levels in the hypothermia group were significantly lower than those in the normothermia group. The early induction of brain hypothermia could facilitate faster recovery of cerebral perfusion pressure, repolarization, and the inhibition of excessive glutamate release, which would prevent ultra-early brain injury following SAH.
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Ma D, An Q, Zhang Z, Bian Q, Li Y, Li Y, Zhang S. Head Mild Hypothermia Exerts a Neuroprotective Role in Ischemia–Reperfusion Injury by Maintaining Glial Glutamate Transporter 1. Ther Hypothermia Temp Manag 2021; 11:155-163. [PMID: 32985953 DOI: 10.1089/ther.2020.0012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Dongyang Ma
- Department of Anesthesiology, Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
| | - Qi An
- Department of Anesthesiology, Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
| | - Zhiqiang Zhang
- Department of Anesthesiology, Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
| | - Qinghu Bian
- Department of Anesthesiology, Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
| | - Yanan Li
- Department of Anesthesiology, Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
| | - Yanli Li
- Department of Anesthesiology, Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
| | - Shan Zhang
- Department of Anesthesiology, Second Hospital of Hebei Medical University, Shijiazhuang, P.R. China
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Ferreira RES, de Paiva BLC, de Freitas FGR, Machado FR, Silva GS, Raposo RM, Silveira CF, Centeno RS. Efficacy and Safety of a Nasopharyngeal Catheter for Selective Brain Cooling in Patients with Traumatic Brain Injury: A Prospective, Non-randomized Pilot Study. Neurocrit Care 2021; 34:581-592. [PMID: 32676873 DOI: 10.1007/s12028-020-01052-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 07/05/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND The efficacy objective was to determine whether a novel nasopharyngeal catheter could be used to cool the human brain after traumatic brain injury, and the safety objective was to assess the local and systemic effects of this therapeutic strategy. METHODS This was a prospective, non-randomized, interventional clinical trial that involved five patients with severe traumatic brain injury. The intervention consisted of inducing and maintaining selective brain cooling for 24 h by positioning a catheter in the nasopharynx and circulating cold water inside the catheter in a closed-loop arrangement. Core temperature was maintained at ≥ 35 °C using counter-warming. RESULTS In all study participants, a brain temperature reduction of ≥ 2 °C was achieved. The mean brain temperature reduction from baseline was 2.5 ± 0.9 °C (P = .04, 95% confidence interval). The mean systemic temperature was 37.3 ± 1.1 °C at baseline and 36.0 ± 0.8 °C during the intervention. The mean difference between the brain temperature and the systemic temperature during intervention was - 1.2 ± 0.8 °C (P = .04). The intervention was well tolerated with no significant changes observed in the hemodynamic parameters. No relevant variations in intracranial pressure and transcranial Doppler were observed. The laboratory results underwent no major changes, aside from the K+ levels and blood counts. The K+ levels significantly varied (P = .04); however, the variation was within the normal range. Only one patient experienced an event of mild localized and superficial nasal discoloration, which was re-evaluated on the seventh day and indicated complete recovery. CONCLUSION The results suggest that our noninvasive method for selective brain cooling, using a novel nasopharyngeal catheter, was effective and safe for use in humans.
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Affiliation(s)
- Raphael Einsfeld Simões Ferreira
- Departamento de Neurologia e Neurocirurgia, Universidade Federal de São Paulo, Av. Moema 170, Cj. 83. Moema, São Paulo, SP, 04077-020, Brazil.
| | | | | | - Flávia Ribeiro Machado
- Departamento de Anestesiologia, Dor e Terapia Intensiva, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Gisele Sampaio Silva
- Departamento de Neurologia e Neurocirurgia, Universidade Federal de São Paulo, Av. Moema 170, Cj. 83. Moema, São Paulo, SP, 04077-020, Brazil
| | - Rafael Mônaco Raposo
- Serviço de Otorrinolaringologia UNIFESP e Serviço de Otorrinolaringologia, Hospital Santa Paula, São Paulo, Brazil
| | - Conrado Feisthauer Silveira
- Departamento de Neurologia e Neurocirurgia, Universidade Federal de São Paulo, Av. Moema 170, Cj. 83. Moema, São Paulo, SP, 04077-020, Brazil
| | - Ricardo Silva Centeno
- Departamento de Neurologia e Neurocirurgia, Universidade Federal de São Paulo, Av. Moema 170, Cj. 83. Moema, São Paulo, SP, 04077-020, Brazil
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Sato S, Takeda Y, Mizoue R, Kawase H, Fushimi M, Shimizu T, Morimatsu H. Determination of the Target Temperature Required to Block Increases in Extracellular Glutamate Levels During Intraischemic Hypothermia. Ther Hypothermia Temp Manag 2018; 8:83-89. [PMID: 29406818 DOI: 10.1089/ther.2017.0041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This study aimed to determine a target temperature for intraischemic hypothermia that can block increases in extracellular glutamate levels. Two groups of 10 rats each formed the normothermia and intraischemic hypothermia groups. Extracellular glutamate levels, the extracellular potential, and the cerebral blood flow were measured at the adjacent site in the right parietal cerebral cortex. Cerebral ischemia was induced by occlusion of the bilateral common carotid arteries and hypotension. In the intraischemic hypothermia group, brain hypothermia was initiated immediately after the onset of membrane potential loss. In the normothermia group, extracellular glutamate levels began to increase simultaneously with the onset of membrane potential loss and reached a maximum level of 341.8 ± 153.1 μmol·L-1. A decrease in extracellular glutamate levels was observed simultaneously with the onset of membrane potential recovery. In the intraischemic hypothermia group, extracellular glutamate levels initially began to increase, similarly to those in the normothermia group, but subsequently plateaued at 140.5 ± 105.4 μmol·L-1, when the brain temperature had decreased to <32.6°C ± 0.9°C. A decrease in extracellular glutamate levels was observed simultaneously with the onset of membrane potential recovery, similarly to the findings in the normothermia group. The rate of decrease in extracellular glutamate levels was the same in both groups (-36.6 and -36.0 μmol·L-1 in the normothermia and intraischemic hypothermia groups, respectively). In conclusion, the target temperature for blocking glutamate release during intraischemic hypothermia was found to be 32.6°C ± 0.9°C. Our results suggest that the induction of intraischemic hypothermia can maintain low glutamate levels without disrupting glutamate reuptake. Institutional protocol number: OKU-2016146.
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Affiliation(s)
- Sachiko Sato
- 1 Department of Anesthesiology, Okayama University Medical School , Okayama, Japan
| | - Yoshimasa Takeda
- 1 Department of Anesthesiology, Okayama University Medical School , Okayama, Japan
| | - Ryoichi Mizoue
- 1 Department of Anesthesiology, Okayama University Medical School , Okayama, Japan
| | - Hirokazu Kawase
- 1 Department of Anesthesiology, Okayama University Medical School , Okayama, Japan
| | - Miki Fushimi
- 1 Department of Anesthesiology, Okayama University Medical School , Okayama, Japan
| | - Tomohisa Shimizu
- 2 Department of Neurological Surgery, Okayama University Medical School , Okayama, Japan
| | - Hiroshi Morimatsu
- 1 Department of Anesthesiology, Okayama University Medical School , Okayama, Japan
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Fukuda T. Targeted temperature management for adult out-of-hospital cardiac arrest: current concepts and clinical applications. J Intensive Care 2016; 4:30. [PMID: 27123306 PMCID: PMC4847228 DOI: 10.1186/s40560-016-0139-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 02/04/2016] [Indexed: 11/25/2022] Open
Abstract
Targeted temperature management (TTM) (primarily therapeutic hypothermia (TH)) after out-of-hospital cardiac arrest (OHCA) has been considered effective, especially for adult-witnessed OHCA with a shockable initial rhythm, based on pathophysiology and on several clinical studies (especially two randomized controlled trials (RCTs) published in 2002). However, a recently published large RCT comparing TTM at 33 °C (TH) and TTM at 36 °C (normothermia) showed no advantage of 33 °C over 36 °C. Thus, this RCT has complicated the decision to perform TH after cardiac arrest. The results of this RCT are sometimes interpreted fever control alone is sufficient to improve outcomes after cardiac arrest because fever control was not strictly performed in the control groups of the previous two RCTs that showed an advantage for TH. Although this may be possible, another interpretation that the optimal target temperature for TH is much lower than 33 °C may be also possible. Additionally, there are many points other than target temperature that are unknown, such as the optimal timing to initiate TTM, the period between OHCA and initiating TTM, the period between OHCA and achieving the target temperature, the duration of maintaining the target temperature, the TTM technique, the rewarming method, and the management protocol after rewarming. RCTs are currently underway to shed light on several of these underexplored issues. In the present review, we examine how best to perform TTM after cardiac arrest based on the available evidence.
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Affiliation(s)
- Tatsuma Fukuda
- Department of Emergency and Critical Care Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8655 Japan
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Cerebral Blood Flow Threshold Is Higher for Membrane Repolarization Than for Depolarization and Is Lowered by Intraischemic Hypothermia in Rats*. Crit Care Med 2015; 43:e350-5. [DOI: 10.1097/ccm.0000000000001095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Feasibility study of immediate pharyngeal cooling initiation in cardiac arrest patients after arrival at the emergency room. Resuscitation 2014; 85:1647-53. [PMID: 25263513 DOI: 10.1016/j.resuscitation.2014.09.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 08/04/2014] [Accepted: 09/06/2014] [Indexed: 11/20/2022]
Abstract
AIM Cooling the pharynx and upper oesophagus would be more advantageous for rapid induction of therapeutic hypothermia since the carotid arteries run in their vicinity. The aim of this study was to determine the effects of pharyngeal cooling on brain temperature and the safety and feasibility for patients under resuscitation. METHODS Witnessed non-traumatic cardiac arrest patients (n=108) were randomized to receive standard care with (n=53) or without pharyngeal cooling (n=55). In the emergency room, pharyngeal cooling was initiated before or shortly after return of spontaneous circulation by perfusing physiological saline (5 °C) into a pharyngeal cuff for 120 min. RESULTS There was a significant decrease in tympanic temperature at 40 min after arrival (P=0.02) with a maximum difference between the groups at 120 min (32.9 ± 1.2°C, pharyngeal cooling group vs. 34.1 ± 1.3°C, control group; P<0.001). The return of spontaneous circulation (70% vs. 65%, P=0.63) and rearrest (38% vs. 47%, P=0.45) rates were not significantly different based on the initiation of pharyngeal cooling. No post-treatment mechanical or cold-related injury was observed on the pharyngeal epithelium by macroscopic observation. The thrombocytopaenia incidence was lower in the pharyngeal cooling group (P=0.001) during the 3-day period after arrival. The cumulative survival rate at 1 month was not significantly different between the two groups. CONCLUSIONS Initiation of pharyngeal cooling before or immediately after the return of spontaneous circulation is safe and feasible. Pharyngeal cooling can rapidly decrease tympanic temperature without adverse effects on circulation or the pharyngeal epithelium.
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Scolletta S, Taccone FS, Nordberg P, Donadello K, Vincent JL, Castren M. Intra-arrest hypothermia during cardiac arrest: a systematic review. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2012; 16:R41. [PMID: 22397519 PMCID: PMC3681365 DOI: 10.1186/cc11235] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2011] [Revised: 02/20/2012] [Accepted: 03/07/2012] [Indexed: 11/23/2022]
Abstract
Introduction Therapeutic hypothermia is largely used to protect the brain following return of spontaneous circulation (ROSC) after cardiac arrest (CA), but it is unclear whether we should start therapeutic hypothermia earlier, that is, before ROSC. Methods We performed a systematic search of PubMed, EMBASE, CINAHL, the Cochrane Library and Ovid/Medline databases using "arrest" OR "cardiac arrest" OR "heart arrest" AND "hypothermia" OR "therapeutic hypothermia" OR "cooling" as keywords. Only studies using intra-arrest therapeutic hypothermia (IATH) were selected for this review. Three authors independently assessed the validity of included studies and extracted data regarding characteristics of the studied cohort (animal or human) and the main outcomes related to the use of IATH: Mortality, neurological status and cardiac function (particularly, rate of ROSC). Results A total of 23 animal studies (level of evidence (LOE) 5) and five human studies, including one randomized controlled trial (LOE 1), one retrospective and one prospective controlled study (LOE 3), and two prospective studies without a control group (LOE 4), were identified. IATH improved survival and neurological outcomes when compared to normothermia and/or hypothermia after ROSC. IATH was also associated with improved ROSC rates and with improved cardiac function, including better left ventricular function, and reduced myocardial infarct size, when compared to normothermia. Conclusions IATH improves survival and neurological outcome when compared to normothermia and/or conventional hypothermia in experimental models of CA. Clinical data on the efficacy of IATH remain limited.
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Affiliation(s)
- Sabino Scolletta
- Department of Intensive Care, Erasme Hospital, Université libre de Bruxelles, Route de Lennik 808, 1070 Brussels, Belgium
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Kaneko T, Kibayashi K. Mild hypothermia facilitates the expression of cold-inducible RNA-binding protein and heat shock protein 70.1 in mouse brain. Brain Res 2012; 1466:128-36. [PMID: 22609236 DOI: 10.1016/j.brainres.2012.05.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Revised: 04/28/2012] [Accepted: 05/01/2012] [Indexed: 10/28/2022]
Abstract
An appropriate thermal control system is essential for maintaining brain homeostasis. Hypothermia is a decrease in core body temperature that occurs when the thermoregulatory responses of homeothermic animals are impaired by environmental and situational influences, such as cold ambience and anesthesia. In recent years, hypothermia has been used for medical treatment, i.e., therapeutic hypothermia, for patients with stroke, traumatic brain injury, and heart surgery. However, the target molecules acting during hypothermia have not been identified. To understand the molecular mechanisms, we generated a mouse model of mild hypothermia (1°C-2°C below normal), and analyzed the expression of several genes. After mice were exposed to cold for 24 and 48 h, their rectal temperature reached 33°C-35°C. Then, using real-time quantitative PCR, we analyzed the mRNA expression levels of c-fos, cold-inducible RNA-binding protein (CIRP), heat shock protein (hsp) 70.1, oxytocin, and representative inflammatory cytokines, i.e., tumor necrosis factor (TNF)-α and interleukin (IL)-6 in target organs. Importantly, we found that the expression levels of CIRP and hsp70.1 were elevated in the olfactory bulb within 48 h. In the hypothalamus, CIRP expression levels increased and were followed by an increase in hsp70.1 expression. Meanwhile, TNF-α and IL-6 expression decreased gradually over 24 and 48 h in the olfactory bulb and hypothalamus. These specific expression profiles, i.e., enhanced CIRP and hsp70.1 expression and depressed cytokine expression, suggest that they could regulate apoptosis related to the cytokine signaling.
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Affiliation(s)
- Tomomi Kaneko
- Department of Legal Medicine, School of Medicine, Tokyo Women's Medical University, 8‐1 Kawada-cho, Shinjuku-ku, Tokyo 162‐8666, Japan.
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Straus D, Prasad V, Munoz L. Selective therapeutic hypothermia: A review of invasive and noninvasive techniques. ARQUIVOS DE NEURO-PSIQUIATRIA 2011; 69:981-7. [DOI: 10.1590/s0004-282x2011000700025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Accepted: 08/03/2011] [Indexed: 12/18/2022]
Abstract
OBJECTIVE: Therapeutic hypothermia is a promising treatment to prevent secondary neurologic injury. Clinical utility is limited by systemic complications of global hypothermia. Selective brain cooling remains a largely uninvestigated application. We review techniques of inducing selective brain cooling. METHOD: Literature review. RESULTS: Strategies of inducing selective brain cooling were divided between non-invasive and invasive techniques. Non-invasive techniques were surface cooling and cooling via the upper airway. Invasive cooling methods include transvascular and compartmental (epidural, subdural, subarachnoid and intraventricular) cooling methods to remove heat from the brain. CONCLUSION: Selective brain cooling may offer the best strategy for achieving hypothermic neuroprotection. Non-invasive strategies have proven disappointing in human trials. There is a paucity of human experiments using invasive methods of selective brain cooling. Further application of invasive cooling strategies is needed.
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Gupta D. Transnasal cooling: a Pandora's box of transnasal patho-physiology. Med Hypotheses 2011; 77:275-7. [PMID: 21600699 DOI: 10.1016/j.mehy.2011.04.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Revised: 04/11/2011] [Accepted: 04/28/2011] [Indexed: 11/18/2022]
Abstract
The innovative concept of transnasal evaporative cooling for therapeutic hypothermia in cardio-pulmonary-cerebro-resuscitation has therapeutic implications with evidence of rapid and selective brain cooling; however, this author wants to elicit that this concept may hold answers for many physiological phenomena which have not been explored or completely understood up till now. To affirm the physiological role of transnasal cooling, the innovative non-invasive brain temperature monitoring can help the investigators to explore and understand the following transnasal pathophysiological phenomena: (1) understanding correlation of brain temperature and sinus headache secondary to nasal blockade, (2) exploring the therapeutic role of nasal oxygen for prevention of delirium in intubated patients, (3) realizing the impact of controlled enclosed environments on the mood and affect of the inhabitants, (4) understanding the etio-pathogenesis of claustrophobia after excluding the confounding factors of morbid obesity, severe cardiopulmonary disease and incapacitating musculoskeletal diseases, (5) exploring the anthropological role of male pattern of moustache, beard and hair loss, and (6) possible development of a coolant moustache as proposed by the author. In summary, transnasal pathophysiology offers many promising lines of fruitful research to explore the non-olfactory physiological functions of nose in human beings.
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Affiliation(s)
- Deepak Gupta
- Department of Anesthesiology, Wayne State University/Detroit Medical Center, School of Medicine, Box No. 162, 3990 John R, Detroit, MI 48201, USA.
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A comparison between head cooling begun during cardiopulmonary resuscitation and surface cooling after resuscitation in a pig model of cardiac arrest. Crit Care Med 2010; 36:S428-33. [PMID: 20449906 DOI: 10.1097/ccm.0b013e31818a8876] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Employing transnasal head-cooling in a pig model of prolonged ventricular fibrillation, we compared the effects of 4 hrs of head-cooling started during cardiopulmonary resuscitation with those of 8 hrs of surface-cooling started at 2 hrs after resuscitation on 96-hr survival and neurologic outcomes. DESIGN Prospective controlled animal study. SETTING University-affiliated research laboratory. SUBJECTS Domestic pigs. INTERVENTIONS Twenty-four male pigs were subjected to 10 min of untreated ventricular fibrillation followed by 5 min of cardiopulmonary resuscitation. In the head-cooling group, hypothermia was started with cardiopulmonary resuscitation and continued for 4 hrs after resuscitation. In the surface-cooling group, systemic hypothermia with a cooling blanket was started, in accord with current clinical practices, at 2 hrs after resuscitation and continued for 8 hrs. Methods in the control animal studies were identical except for temperature interventions. MEASUREMENTS AND MAIN RESULTS All animals were resuscitated except for one animal in each of the surface-cooling and control groups. After 5 min of cardiopulmonary resuscitation, jugular vein temperature was significantly decreased in the head-cooled animals. However, there were no differences in pulmonary artery temperatures among the three groups at that time. Nevertheless, both head-cooled and surface-cooled animals had an improved 96-hr survival after resuscitation. Significantly better neurologic outcomes were observed in early head-cooled animals in the first 3 days after resuscitation. CONCLUSION Early head-cooling during cardiopulmonary resuscitation continuing for 4 hrs after resuscitation produced favorable survival and neurologic outcomes in comparison with delayed surface-cooling of 8 hrs duration.
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Zushi R, Hazui H, Hoshiga M, Yagi Y, Goto T, Mori T, Kawakami M, Nishihara I, Kobata H, Ohishi Y, Akimoto H. Therapeutic hypothermia with immunosuppressive drugs for a comatose renal transplant patient who survived out-of-hospital cardiac arrest. J Cardiol Cases 2010; 1:e147-e150. [PMID: 30524525 DOI: 10.1016/j.jccase.2009.12.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2009] [Revised: 11/28/2009] [Accepted: 12/04/2009] [Indexed: 11/19/2022] Open
Abstract
A 31-year-old man suddenly collapsed at work. His colleagues witnessed the event, applied basic life support, and called for an ambulance. After the ambulance arrived, the initial rhythm was confirmed as ventricular fibrillation (VF) and he was defibrillated with an automated external defibrillator. Spontaneous circulation was regained at 8 min after collapse. He was thought to be a good candidate for therapeutic hypothermia because he was comatose and had survived outside hospital VF cardiac arrest due to cardiac etiology. However, he was taking immunosuppressive drugs after undergoing a kidney transplant. We obtained written, informed consent from the patient's family to start therapeutic hypothermia at 33.5-34.5 °C for 48 h, although he was at high risk for such induction. Serious complications and neurological deficits did not develop and the patient was referred to another hospital on day 42 for implantation with a cardioverter defibrillator.
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Affiliation(s)
- Ryosuke Zushi
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Hiroshi Hazui
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Masaaki Hoshiga
- First Department of Internal Medicine, Osaka Medical College, Takatsuki, Osaka, Japan
| | - Yoshiki Yagi
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Takuya Goto
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Toshizumi Mori
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Makiko Kawakami
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Isao Nishihara
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Hitoshi Kobata
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Yasuo Ohishi
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
| | - Hiroshi Akimoto
- Department of Emergency Medicine, Osaka Mishima Emergency and Critical Care Center, 11-1 Minami Akutagawa-cho, Takatsuki, Osaka 569-1124, Japan
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Weis J, Covaciu L, Rubertsson S, Allers M, Lunderquist A, Ahlström H. Noninvasive monitoring of brain temperature during mild hypothermia. Magn Reson Imaging 2009; 27:923-32. [PMID: 19282122 DOI: 10.1016/j.mri.2009.01.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Accepted: 01/11/2009] [Indexed: 10/21/2022]
Abstract
The main purpose of this study was to verify the feasibility of brain temperature mapping with high-spatial- and reduced-spectral-resolution magnetic resonance spectroscopic imaging (MRSI). A secondary goal was to determine the temperature coefficient of water chemical shift in the brain with and without internal spectral reference. The accuracy of the proposed MRSI method was verified using a water and vegetable oil phantom. Selective decrease of the brain temperature of pigs was induced by intranasal cooling. Temperature reductions between 2 degrees C and 4 degrees C were achieved within 20 min. The relative changes in temperature during the cooling process were monitored using MRSI. The reference temperature was measured with MR-compatible fiber-optic probes. Single-voxel (1)H MRS was used for measurement of absolute brain temperature at baseline and at the end of cooling. The temperature coefficient of the water chemical shift of brain tissue measured by MRSI without internal reference was -0.0192+/-0.0019 ppm/degrees C. The temperature coefficients of the water chemical shift relative to N-acetylaspartate, choline-containing compounds and creatine were -0.0096+/-0.0009, -0.0083+/-0.0007 and -0.0091+/-0.0011 ppm/degrees C, respectively. The results of this study indicate that MRSI with high spatial and reduced spectral resolutions is a reliable tool for monitoring long-term temperature changes in the brain.
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Affiliation(s)
- Jan Weis
- Department of Radiology, MR Unit, Uppsala University Hospital, Uppsala, Sweden.
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17
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Katz LM, Frank JE, Dvorak A, Finch A, Szymanowski A, Gordon CJ. Independence of brain and trunk temperature during hypothermic preconditioning in rats. J Neurosci Methods 2009; 179:179-83. [PMID: 19428525 DOI: 10.1016/j.jneumeth.2009.01.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2008] [Revised: 01/24/2009] [Accepted: 01/26/2009] [Indexed: 12/01/2022]
Abstract
UNLABELLED Hypothermic preconditioning is rapid cooling and warming to induce tolerance to ischemia. The purpose of the study was to examine differences in brain and trunk temperature during hypothermic preconditioning. METHODS Rats (n=18) were implanted with telemetric probes for simultaneous measure of brain and trunk temperature. Hypothermic preconditioning was produced by exposing rats to cool and warm environments that produced rapid cooling to 30 degrees C and warming to 35 degrees C. RESULTS Brain temperature was warmer (37.56+/-0.45 degrees C) than trunk (37.17+/-0.29 degrees C) temperature in unanesthetized, free roaming rats at room temperature (t-test p=0.04). The brain cooled (0.59+/-0.1 degrees C/min) quicker than the trunk (0.44+/-0.19 degrees C/min) during cooling cycles of hypothermic preconditioning and the brain (0.28+/-0.04 degrees C/min) warmed quicker than the trunk (0.18+/-0.07 degrees C/min) during the warming cycle of hypothermic preconditioning (t-test p<0.0001). When the trunk temperature probe was designated to reach the target temperature of 35 degrees C during warming, the brain temperature (38.1+/-0.44 degrees C) was warmer than trunk temperature (34.95+/-0.16 degrees C) during the peak of warming (t-test p<0.0001). CONCLUSION The brain cools and warms quicker than the trunk during hypothermic preconditioning. Failure to anticipate these differences could lead to unrecognized brain hyperthermia during warming. Appreciation of differences in rates of change between brain and trunk temperature may be important when designing hypothermic preconditioning experiments.
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Affiliation(s)
- Laurence M Katz
- University of North Carolina School of Medicine, Department of Emergency Medicine, CB 7594, Neurosciences Hospital Ground Floor, 101 Manning Drive, Chapel Hill, NC 27599, USA.
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18
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Hauck EF, Wei J, Quast MJ, Nauta HJW. A new technique allowing prolonged temporary cerebral artery occlusion. J Neurosurg 2008; 109:1127-33. [PMID: 19035732 DOI: 10.3171/jns.2008.109.12.1127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Clipping of complex cerebral aneurysms often requires temporary vessel occlusion. The risk of stroke, however, increases exponentially with occlusion time. The authors hypothesized that prolonged temporary occlusion might be tolerated if the occluded vessels were perfused with cold physiological saline solution (CPSS). A low-flow perfusion rate would permit surgical manipulation of an aneurysm distal to the occlusion. METHODS To test this hypothesis, the authors temporarily occluded the middle cerebral artery (MCA) with an endovascular catheter in 6 rats. Three animals, the treatment group, were perfused with 5-ml CPSS/hour through the occluding endovascular catheter into the MCA, and the other 3 served as an ischemic control group. In both groups, the catheter was removed after 90 minutes of occlusion. The brain temperature was monitored with a stereotactically placed probe in the caudate-putamen in 2 separate experimental groups (11 animals). RESULTS Magnetic resonance imaging perfusion scanning during vessel occlusion confirmed similar reduction of cerebral blood flow during MCA occlusion in both the simple-occlusion and perfusion-occlusion groups. Magnetic resonance imaging diffusion scans performed 24 hours after temporary occlusion revealed infarcts in the ischemic control group of 138.3 +/- 28.0 mm(3) versus 9.9 +/- 9.9 mm(3) in the cold saline group (p < 0.005). A focal cooling effect during perfusion with CPSS was demonstrated (p < 0.05). CONCLUSIONS Prolonged temporary cerebral vessel occlusion can be tolerated using superselective CPSS perfusion through an occluding endovascular catheter into the ischemic territory. This technique could possibly be applied in neurosurgery practice to the management of complex intracranial aneurysms.
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Affiliation(s)
- Erik F Hauck
- Division of Neurosurgery, University of Texas Medical Branch at Galveston, Texas, USA.
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19
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Nagel S, Papadakis M, Hoyte L, Buchan AM. Therapeutic hypothermia in experimental models of focal and global cerebral ischemia and intracerebral hemorrhage. Expert Rev Neurother 2008; 8:1255-68. [PMID: 18671669 DOI: 10.1586/14737175.8.8.1255] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Experimental evidence shows that therapeutic hypothermia (TH) protects the brain from cerebral injury in multiple ways. In different models of focal and global cerebral ischemia, mild-to-moderate hypothermia reduces mortality and neuronal injury and improves neurological outcome. In models of experimental intracerebral hemorrhage (ICH), TH reduces edema formation but does not show consistent benefi cial effects on functional outcome parameters. However, the number of studies of hypothermia on ICH is still limited. TH is most effective when applied before or during the ischemic event, and its neuroprotective properties vary according to species, strains and the model of ischemia used. Intrinsic changes in body and brain temperature frequently occur in experimental models of focal and global cerebral ischemia, and may have infl uenced studies on other neuroprotectants. This might be one explanation for the failure of a large amount of translational clinical neuroprotective trials. Hypothermia is the only neuroprotective therapeutic agent for cerebral ischemia that has successfully managed the transfer from bench to bedside, and it is an approved therapy for patients after cardiac arrest and children with hypoxic-ischemic encephalopathy. However, the implementation of hypothermia in the treatment of stroke patients is still far from routine clinical practice. In this article, the authors describe the development of TH in different models of focal and global cerebral ischemia, point out why hypothermia is so efficient in experimental cerebral ischemia, explain why temperature regulation is essential for further neuroprotective studies and discuss why TH for acute ischemic stroke still remains a promising but controversial therapeutic option.
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Affiliation(s)
- Simon Nagel
- Acute Stroke Programme, Nuffield Department of Clinical Medicine, John Radcliffe Hospital, Oxford, OX3 9DU, UK.
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21
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Cooling Therapies after Neuronal Injury: Direct Brain Cooling and Systemic Hypothermia. Intensive Care Med 2007. [DOI: 10.1007/978-0-387-49518-7_63] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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22
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Covaciu L, Allers M, Enblad P, Lunderquist A, Wieloch T, Rubertsson S. Intranasal selective brain cooling in pigs. Resuscitation 2007; 76:83-8. [PMID: 17709167 DOI: 10.1016/j.resuscitation.2007.07.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2007] [Revised: 06/20/2007] [Accepted: 07/02/2007] [Indexed: 11/28/2022]
Abstract
BACKGROUND Special clinical situations where general hypothermia cannot be recommended but can be a useful treatment demand a new approach, selective brain cooling. The purpose of this study was to selectively cool the brain with cold saline circulating in balloon catheters introduced into the nasal cavity in pigs. MATERIAL AND METHODS Twelve anaesthetised pigs were subjected to selective cerebral cooling for a period of 6 h. Cerebral temperature was lowered by means of bilaterally introduced nasal balloon catheters perfused with saline cooled by a heat exchanger to 8-10 degrees C. Brain temperature was measured in both cerebral hemispheres. Body temperature was measured in rectum, oesophagus and the right atrium. The pigs were normoventilated and haemodynamic variables were measured continuously. Acid-base and electrolyte status was measured hourly. RESULTS Cerebral hypothermia was induced rapidly and within the first 20 min of cooling cerebral temperature was lowered from 38.1+/-0.6 degrees C by a mean of 2.8+/-0.6 to 35.3+/-0.6 degrees C. Cooling was maintained for 6 h and the final brain temperature was 34.7+/-0.9 degrees C. Concomitantly, the body temperature, as reflected by oesophageal temperature was decreased from 38.3+/-0.5 to 36.6+/-0.9 degrees C. No circulatory or metabolic disturbances were noted. CONCLUSIONS Inducing selective brain hypothermia with cold saline via nasal balloon catheters can effectively be accomplished in pigs, with no major disturbances in systemic circulation or physiological variables. The temperature gradients between brain and body can be maintained for at least 6 h.
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Affiliation(s)
- L Covaciu
- Anesthesiology and Intensive Care, Uppsala University, Uppsala, Sweden.
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23
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Qiu W, Shen H, Zhang Y, Wang W, Liu W, Jiang Q, Luo M, Manou M. Noninvasive selective brain cooling by head and neck cooling is protective in severe traumatic brain injury. J Clin Neurosci 2007; 13:995-1000. [PMID: 17113984 DOI: 10.1016/j.jocn.2006.02.027] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2005] [Accepted: 02/17/2006] [Indexed: 11/22/2022]
Abstract
Therapeutic hypothermia is a promising treatment for patients with severe traumatic brain injury (TBI). We present here the results of a study in which noninvasive selective brain cooling (SBC) was achieved using a head cap and neckband. Ninety patients with severe TBI were divided into a normothermia control group (n=45) and a SBC group (n=45), whose brain temperature was maintained at 33-35 degrees C for 3 days using a combination of head and neck cooling. At 24, 48 and 72h after injury, the mean intracranial pressure (ICP) values of the patients who underwent SBC were lower than those of the normothermia controls (19.14+/-2.33, 19.72+/-1.73 and 17.29+/-2.07 mmHg, versus 23.41+/-2.51, 20.97+/-1.86, and 20.13+/-1.87 mmHg, respectively, P<0.01). There was a significant difference in the neurological recovery of the two groups at the 6-month follow-up after TBI. Good neurological outcome (Glasgow Outcome Scale score of 4 to 5) rates 6 months after injury were 68.9% for the SBC group, and 46.7% for the control group (P<0.05). There were no complications resulting in severe sequelae. In conclusion, the noninvasive SBC described here is a safe method of administering therapeutic hypothermia, which can reduce ICP and improve prognosis without severe complications in patients with severe TBI.
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Affiliation(s)
- Wusi Qiu
- Brain Center, Department of Neurosurgery, Second Affiliated Hospital, Zhejiang University, School of Medicine, 88 Jiefang Road, Hangzhou 310009, China
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Dohi K, Jimbo H, Abe T, Aruga T. Positive selective brain cooling method: a novel, simple, and selective nasopharyngeal brain cooling method. ACTA NEUROCHIRURGICA. SUPPLEMENT 2006; 96:409-12. [PMID: 16671495 DOI: 10.1007/3-211-30714-1_84] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Brain damage is worsened by hyperthermia and prevented by hypothermia. Conventional hypothermia is a non-selective brain cooling method that employs cooling blankets to achieve surface cooling. This complicated method sometimes induces unfavorable systemic complications. We have developed a positive selective brain cooling (PSBC) method to control brain temperature quickly and safely following brain injury. Brain temperature was measured in patients with a ventriculostomy CAMINO catheter. A Foley balloon catheter was inserted to direct chilled air (8 to 12 L/min) into each side of the nasal cavity. The chilled air was exhaled through the oral cavity. In most patients, PSBC maintained normal brain temperature. This new technique provides quick induction of brain temperature control and does not require special facilities.
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Affiliation(s)
- K Dohi
- Department of Emergency and Critical Care Medicine, Showa University School of Medicine, Tokyo, Japan.
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25
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Liu WG, Qiu WS, Zhang Y, Wang WM, Lu F, Yang XF. Effects of selective brain cooling in patients with severe traumatic brain injury: a preliminary study. J Int Med Res 2006; 34:58-64. [PMID: 16604824 DOI: 10.1177/147323000603400107] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We prospectively investigated non-invasive selective brain cooling (SBC) in patients with severe traumatic brain injury. Sixty-six in-patients were randomized into three groups. In one group, brain temperature was maintained at 33 - 35 degrees C by cooling the head and neck (SBC); in a second group, mild systemic hypothermia (MSH; rectal temperature 33 - 35 degrees C) was produced with a cooling blanket; and a control group was not exposed to hypothermia. Natural rewarming began after 3 days. Mean intracranial pressure 24, 48 or 72 h after injury was significantly lower in the SBC group than in the control group. Mean serum superoxide dismutase levels on Days 3 and 7 after injury in the SBC and MSH groups were significantly higher than in the control group. The percentage of patients with a good neurological outcome 2 years after injury was 72.7%, 57.1% and 34.8% in the SBC, MSH and control groups, respectively. Complications were managed without severe sequelae. Non-invasive SBC was safe and effective.
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Affiliation(s)
- W G Liu
- Department of Neurosurgery, The Second Affiliated Hospital, College of Medicine, Zhejiang University, China
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Takata K, Takeda Y, Sato T, Nakatsuka H, Yokoyama M, Morita K. Effects of hypothermia for a short period on histologic outcome and extracellular glutamate concentration during and after cardiac arrest in rats*. Crit Care Med 2005; 33:1340-5. [PMID: 15942353 DOI: 10.1097/01.ccm.0000166351.19369.d3] [Citation(s) in RCA: 65] [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
OBJECTIVE To evaluate the therapeutic effects of hypothermia for a short period (20 mins, 31 degrees C) using a cardiac arrest model (5 mins) in rats. DESIGN Prospective animal study. SETTING Experimental laboratory in a university hospital. SUBJECTS Male Wistar rats (n = 42). INTERVENTION Direct current (DC) potential and extracellular glutamate concentrations (microdialysis) were monitored in the hippocampal region. Histologic observation was performed 7 days later. MEASUREMENTS AND MAIN RESULTS No animal died or showed severe complications as a result of hypothermia for a short period. In nontreated animals (group F), extracellular glutamate concentration simultaneously increased with the onset of membrane depolarization and continued to increase during the reperfusion period (maximum, 212% +/- 40% of the pre-ischemia level) until the onset of DC recovery. In animals in which hypothermia was initiated before the onset of ischemia (group A), extracellular glutamate concentration did not increase during the ischemia period. When hypothermia was initiated at the onset of resuscitation (group B), the glutamate concentration immediately decreased. In animals in which hypothermia was initiated at 4.9 +/- 1.3 mins (immediately after DC recovery, group C), 10 mins (group D), and 20 mins (group E) after the onset of resuscitation, changes in extracellular glutamate concentration were the same as those in nontreated animals. The percentage of injured neurons was significantly attenuated (compared with group F, 82% +/- 10%) when hypothermia was initiated before DC recovery (group A, 5% +/- 3%; group B, 29% +/- 22%) or immediately after DC recovery (group C, 58% +/- 18%, 9.9 +/- 1.3 mins after the onset of ischemia). CONCLUSIONS Hypothermia for a short period decreased glutamate concentration when it was initiated before DC recovery and attenuated neuronal damage when it was initiated before or immediately after DC recovery. The therapeutic time window for hypothermia for a short period is about 10 mins after the onset of ischemia.
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Affiliation(s)
- Ken Takata
- Department of Anesthesiology and Resuscitology, Okayama University Medical School, Okayama City, Okayama, Japan
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