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Bardutzky J, Kollmar R, Al-Rawi F, Lambeck J, Fazel M, Taschner C, Niesen WD. COmbination of Targeted temperature management and Thrombectomy after acute Ischemic Stroke (COTTIS): a pilot study. Stroke Vasc Neurol 2024; 9:258-267. [PMID: 37612052 PMCID: PMC11221305 DOI: 10.1136/svn-2023-002420] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 08/05/2023] [Indexed: 08/25/2023] Open
Abstract
BACKGROUND To evaluate the feasibility and safety of a fast initiation of cooling to a target temperature of 35°C by means of transnasal cooling in patients with anterior circulation large vessel occlusion (LVO) undergoing endovascular thrombectomy (EVT). METHODS Patients with an LVO onset of <24 hour who had an indication for EVT were included in the study. Transnasal cooling (RhinoChill) was initiated immediately after the patient was intubated for EVT and continued until an oesophageal target temperature of 35°C was reached. Hypothermia was maintained with surface cooling for 6-hour postrecanalisation, followed by active rewarming (+0.2°C/hour). The primary outcome was defined as the time required to reach 35°C, while secondary outcomes comprised clinical, radiological and safety parameters. RESULTS Twenty-two patients (median age, 77 years) were included in the study (14 received additional thrombolysis, 4 additional stenting of the proximal internal carotid artery). The median time intervals were 309 min for last-seen-normal-to-groin, 58 min for door-to-cooling-initiation, 65 min for door-to-groin and 123 min for door-to-recanalisation. The target temperature of 35°C was reached within 30 min (range 13-78 min), corresponding to a cooling rate of 2.6 °C/hour. On recanalisation, 86% of the patients had a body temperature of ≤35°C. The median National Institutes of Health Stroke Scale at admission was 15 and improved to 2 by day 7, and 68% of patients had a good outcome (modified Rankin Scale 0-2) at 3 months. Postprocedure complications included asymptomatic bradycardia (32%), pneumonia (18%) and asymptomatic haemorrhagic transformation (18%). CONCLUSION The combined application of hypothermia and thrombectomy was found to be feasible in sedated and ventilated patents. Adverse events were comparable to those previously described for EVT in the absence of hypothermia. The effect of this procedure will next be evaluated in the randomised COmbination of Targeted temperature management and Thrombectomy after acute Ischemic Stroke-2 trial.
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Affiliation(s)
- Jürgen Bardutzky
- Department of Neurology and Neurophysiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Rainer Kollmar
- Neurology and Neurointensive Care, Darmstadt Hospital, Darmstadt, Germany
| | - Forat Al-Rawi
- Department of Neurology and Neurophysiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Johann Lambeck
- Department of Neurology and Neurophysiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | | | - Christian Taschner
- Department of Neuroradiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Wolf-Dirk Niesen
- Department of Neurology and Neurophysiology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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Abstract
PURPOSE OF REVIEW To address the impact of therapeutic hypothermia induced already during cardiopulmonary resuscitation (i.e. intra-arrest cooling) and its association with neurologic functional outcome. RECENT FINDINGS Intra-arrest cooling is superior than post-ROSC cooling to mitigate brain injuries in experimental models of cardiac arrest. The delayed initiation of hypothermia in human studies may not have adequately addressed the underlying pathophysiology of ischemia and reperfusion. The assessment of early initiation of cooling has been complicated by increased rate of hemodynamic adverse events caused by infusion of cold intravenous fluids. These adverse events have been more deleterious in patients with initial shockable rhythms. A recent randomized study shows that an alternative intra-arrest cooling method using trans-nasal evaporative cooling was well tolerated and effective to shorten time to target temperature. However, the neurologic outcomes (CPC 1-2 at 90 days) in favor of intra-arrest cooling compared to hospital cooling (34.8% vs 25.9%, P = 0.11) in patients with initial shockable rhythms did not reach statistical significance. SUMMARY Therapeutic intra-arrest hypothermia can be initiated safely at the scene of the arrest using transnasal evaporative cooling. The potential beneficial effect of intra-arrest cooling on neurologic recovery in patients with initial shockable rhythms should be explored further.
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de Paiva BLC, Bor-Seng-Shu E, Silva E, Barreto ÍBM, de Lima Oliveira M, Ferreira RES, Cavalcanti AB, Teixeira MJ. Inducing Brain Cooling Without Core Temperature Reduction in Pigs Using a Novel Nasopharyngeal Method: An Effectiveness and Safety Study. Neurocrit Care 2020; 32:564-574. [PMID: 31317319 PMCID: PMC7223440 DOI: 10.1007/s12028-019-00789-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Acute brain lesions constitute an alarming public health concern. Neuroprotective therapies have been implemented to stabilize, prevent, or reduce brain lesions, thus improving neurological outcomes and survival rates. Hypothermia is the most effective approach, mainly attributed to the reduction in cellular metabolic activity. Whole-body cooling is currently implemented by healthcare professionals; however, adverse events are frequent, limiting the potential benefits of therapeutic hypothermia. Therefore, selective methods have been developed to reduce adverse events while delivering neuroprotection. Nasopharyngeal approaches are the safest and most effective methods currently considered. Our primary objective was to determine the effects of a novel nasopharyngeal catheter on the brain temperature of pigs. METHODS In this prospective, non-randomized, interventional experimental trial, 10 crossbred pigs underwent nasopharyngeal cooling for 60 min followed by 15 min of rewarming. Nasopharyngeal catheters were inserted into the left nostril and properly positioned at the nasopharyngeal cavity. RESULTS Nasopharyngeal cooling was associated with a decrease in brain temperature, which was more significant in the left cerebral hemisphere (p = 0.01). There was a reduction of 1.47 ± 0.86 °C in the first 5 min (p < 0.001), 2.45 ± 1.03 °C within 10 min (p < 0.001), and 4.45 ± 1.36 °C after 1 h (p < 0.001). The brain-core gradient was 4.57 ± 0.87 °C (p < 0.001). Rectal, esophageal, and pulmonary artery temperatures and brain and systemic hemodynamic parameters, remained stable during the procedure. Following brain cooling, values of oxygen partial pressure in brain tissue significantly decreased. No mucosal lesions were detected during nasal, pharyngeal, or oral inspection after nasopharyngeal catheter removal. CONCLUSIONS In this study, a novel nasopharyngeal cooling catheter effectively induced and maintained exclusive brain cooling when combined with effective counter-warming methods. Exclusive brain cooling was safe with no device-related local or systemic complications and may be desired in selected patient populations.
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Affiliation(s)
- Bernardo Lembo Conde de Paiva
- Neurology Department, School of Medicine, University of São Paulo, Avenida Moema, 170, Cj. 83 - Moema, São Paulo, SP, CEP: 04077-020, Brazil.
- Neurocritical Care Unit, Hospital Santa Paula, São Paulo, SP, Brazil.
| | - Edson Bor-Seng-Shu
- Neurology Department, School of Medicine, University of São Paulo, Avenida Moema, 170, Cj. 83 - Moema, São Paulo, SP, CEP: 04077-020, Brazil
- Neurocritical Care Unit, Hospital Santa Paula, São Paulo, SP, Brazil
| | - Eliezer Silva
- Intensive Care Unit, Hospital Israelita Albert Einstein, São Paulo, Brazil
| | | | - Marcelo de Lima Oliveira
- Neurology Department, School of Medicine, University of São Paulo, Avenida Moema, 170, Cj. 83 - Moema, São Paulo, SP, CEP: 04077-020, Brazil
- Neurocritical Care Unit, Hospital Santa Paula, São Paulo, SP, Brazil
| | - Raphael Einsfeld Simões Ferreira
- Neurocritical Care Unit, Hospital Santa Paula, São Paulo, SP, Brazil
- Research Centre, Centro Universitário São Camilo, São Paulo, SP, Brazil
| | | | - Manoel Jacobsen Teixeira
- Neurology Department, School of Medicine, University of São Paulo, Avenida Moema, 170, Cj. 83 - Moema, São Paulo, SP, CEP: 04077-020, Brazil
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Chen Y, Quddusi A, Harrison KA, Ryan PE, Cook DJ. Selection of preclinical models to evaluate intranasal brain cooling for acute ischemic stroke. Brain Circ 2019; 5:160-168. [PMID: 31950091 PMCID: PMC6950506 DOI: 10.4103/bc.bc_20_19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 10/28/2019] [Indexed: 01/12/2023] Open
Abstract
Stroke accounts for a large proportion of global mortality and morbidity. Selective hypothermia, via intranasal cooling devices, is a promising intervention in acute ischemic stroke. However, prior to large clinical trials, preclinical studies in large animal models of ischemic stroke are needed to assess the efficacy, safety, and feasibility of intranasal cooling for selective hypothermia as a neuroprotective strategy. Here, we review the available scientific literature for evidence supporting selective hypothermia and make recommendations of a preclinical, large, animal-based, ischemic stroke model that has the greatest potential for evaluating intranasal cooling for selective hypothermia and neuroprotection. We conclude that among large animal models of focal ischemic stroke including pigs, sheep, dogs, and nonhuman primates (NHPs), cynomolgus macaques have nasal anatomy, nasal vasculature, neuroanatomy, and cerebrovasculature that are most similar to those of humans. Moreover, middle cerebral artery stroke in cynomolgus macaques produces functional and behavioral deficits that are quantifiable to a greater degree of precision and detail than those that can be revealed through available assessments for other large animals. These NHPs are also amenable to extensive neuroimaging studies as a means of monitoring stroke evolution and evaluating infarct size. Hence, we suggest that cynomolgus macaques are best suited to assess the safety and efficacy of intranasal selective hypothermia through an evaluation of hyperacute diffusion-weighted imaging and subsequent investigation of chronic functional recovery, prior to randomized clinical trials in humans.
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Affiliation(s)
- Yining Chen
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Ayesha Quddusi
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | | | - Paige E Ryan
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada
| | - Douglas J Cook
- Centre for Neuroscience Studies, Queen's University, Kingston, ON, Canada.,Department of Surgery, Division of Neurosurgery, Kingston General Hospital, Kingston, ON, Canada
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Neuroprotective Effects of Nasopharyngeal Perfluorochemical Cooling in a Rat Model of Subarachnoid Hemorrhage. World Neurosurg 2018; 121:e481-e492. [PMID: 30267945 DOI: 10.1016/j.wneu.2018.09.142] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 09/16/2018] [Accepted: 09/18/2018] [Indexed: 11/22/2022]
Abstract
OBJECTIVE Subarachnoid hemorrhage (SAH) frequently results in severe morbidity, even mortality. Hypothermia is known to have a neuroprotective effect in ischemic injuries. The aim of this study was to determine whether nasopharyngeal (NP) perfluorochemical (PFC) cooling could be used in a rat model of SAH model for neuroprotection. METHODS SAH was induced in 16 male Sprague-Dawley rats by cisterna magna injection of 0.3 mL autologous blood. Vital signs, temperatures, cerebral blood flow (CBF), and brain histology were assessed. Brain cooling was performed on the treatment group using the NP-PFC method starting from 20 minutes after SAH. RESULTS No SAH-related deaths were observed in either group. SAH caused an immediate decrease in mean arterial pressure (17.0% ± 4.90% below baseline values). SAH induction caused a significant and rapid decrease in CBF from baseline (approximately -65%, ranging from -32% to -85%) in both hemispheres. In the left hemisphere, cooling facilitated the return of CBF to baseline values within 20 minutes of treatment with further increase in CBF that stabilized by the 2 hours after injury time point. Quantitative immunohistochemistry showed that there were significantly more NeuN-positive cells in the cortex and significantly fewer IBA-1-positive microglia and glial fibrillary acidic protein-positive astrocytes cells in both cortex and hippocampus in the animals that received NP-PFC cooling compared with no treatment, reflecting preserved neuronal integrity and reduced inflammation. CONCLUSIONS The data from this study indicate that local hypothermia by NP-PFC cooling supports return of CBF and neuronal integrity and suppresses the inflammatory response in SAH, suggestive of a promising neuroprotective approach in management of SAH.
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Sedlacik J, Kjørstad Å, Nagy Z, Buhk JH, Behem CR, Trepte CJ, Fiehler J, Temme F. Feasibility Study of a Novel High-Flow Cold Air Cooling Protocol of the Porcine Brain Using MRI Temperature Mapping. Ther Hypothermia Temp Manag 2017; 8:45-52. [PMID: 29099343 DOI: 10.1089/ther.2017.0031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Early, prehospital cooling seeks to reduce and control the body temperature as early as possible to protect the brain and improve patient outcome in cardiac arrest, stroke, and traumatic brain injury. In this study, we investigate the feasibility of localized cooling of the porcine brain by using a novel high-flow cold air protocol, which utilizes the close proximity between the nasal cavity and the brain. Five adult pigs were anesthetized and temperature change was mapped before, during, and after cooling by using the proton resonance frequency method on a 3 T Siemens Magnetom Skyra system. Cooling was performed by inserting a tube blowing high-flow (250 L/min) cold air (-10°C) through the nasal cavity for 5-20 minutes. The brain temperature change was measured by using an MRI phase mapping technique utilizing the temperature-dependent proton resonance frequency change. MRI maps showed significant temperature reduction of the porcine brain. On average, a mean whole-brain cooling effect of -0.33°C ± 0.30°C was found after 5 minutes of cooling. The anterior part of the brain was directly exposed to the cold and showed a significantly larger temperature drop (-0.83°C ± 0.51°C) than the posterior part (-0.03°C ± 0.21°C). However, a large variability of the temperature drop was observed between the animals. This variability may be caused by not well-controlled factors confounding the MRI temperature mapping, for example, subject movement, or cooling effectiveness, for example, core temperature or nasal patency. The results indicate that the proposed high-flow cold air protocol allows for localized cooling of the frontal porcine brain, which may be clinically relevant for traumatic injuries of the frontal brain where systemic cooling is unfavorable.
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Affiliation(s)
- Jan Sedlacik
- 1 Department of Neuroradiology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
| | - Åsmund Kjørstad
- 1 Department of Neuroradiology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
| | - Zsuzsanna Nagy
- 1 Department of Neuroradiology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
| | - Jan-Hendrik Buhk
- 1 Department of Neuroradiology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
| | - Christoph R Behem
- 2 Department of Anaesthesiology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
| | - Constantin J Trepte
- 2 Department of Anaesthesiology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
| | - Jens Fiehler
- 1 Department of Neuroradiology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
| | - Fabian Temme
- 1 Department of Neuroradiology, University Medical Center Hamburg-Eppendorf , Hamburg, Germany
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7
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Abstract
BACKGROUND Mild hypothermia is an effective neuroprotective strategy for a variety of acute brain injuries. Cooling the nasopharynx may offer the capability to cool the brain selectively due to anatomic proximity of the internal carotid artery to the cavernous sinus. This study investigated the feasibility and efficiency of nasopharyngeal brain cooling by continuously blowing room temperature or cold air at different flow rates into the nostrils of normal newborn piglets. METHODS Experiments were conducted on thirty piglets (n = 30, weight = 2.7 ± 1.5 kg). Piglets were anesthetized with 1–2% isoflurane and were randomized to receive one of four different nasopharyngeal cooling treatments: I. Room temperature at a flow rate of 3–4 L min(−1) (n = 6); II. −1 ± 2 °C at a flow rate of 3–4 L min(−1) (n = 6); III. Room temperature at a flow rate of 14–15 L min(−1) (n = 6); IV. −8 ± 2 °C at a flow rate of 14–15 L min(−1) (n = 6). To control for the normal thermal regulatory response of piglets without nasopharyngeal cooling, a control group of piglets (n = 6) had their brain temperature monitored without nasopharyngeal cooling. The duration of treatment was 60 min, with additional 30 min of observation. RESULTS In group I, median cooling rate was 1.7 ± 0.9 °C/h by setting the flow rate of room temperature air to 3–4 L min(−1). Results of comparing different temperatures and flow rates in the nasopharyngeal cooling approach reveal that the brain temperature could be reduced rapidly at a rate of 5.5 ± 1.1 °C/h by blowing −8 ± 2 °C air at a flow rate of 14–15 L min(−1). CONCLUSIONS Nasopharyngeal cooling via cooled insufflated air can lower the brain temperature, with higher flows and lower temperatures of insufflated air being more effective.
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Kohlhauer M, Berdeaux A, Kerber RE, Micheau P, Ghaleh B, Tissier R. Liquid Ventilation for the Induction of Ultrafast Hypothermia in Resuscitation Sciences: A Review. Ther Hypothermia Temp Manag 2016; 6:63-70. [DOI: 10.1089/ther.2015.0024] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Matthias Kohlhauer
- Inserm, Unité 955, Equipe 03, Créteil, France
- Université Paris Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France
- Université Paris Est, École Nationale Vétérinaire d'Alfort, Maisons-Alfort Cedex, France
| | - Alain Berdeaux
- Inserm, Unité 955, Equipe 03, Créteil, France
- Université Paris Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France
- Université Paris Est, École Nationale Vétérinaire d'Alfort, Maisons-Alfort Cedex, France
| | - Richard E. Kerber
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Iowa Hospitals and Clinics, Iowa City, Iowa
| | - Philippe Micheau
- Department of Mechanical Engineering, Université de Sherbrooke, Sherbrooke, Canada
| | - Bijan Ghaleh
- Inserm, Unité 955, Equipe 03, Créteil, France
- Université Paris Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France
- Université Paris Est, École Nationale Vétérinaire d'Alfort, Maisons-Alfort Cedex, France
| | - Renaud Tissier
- Inserm, Unité 955, Equipe 03, Créteil, France
- Université Paris Est, UMR_S955, DHU A-TVB, UPEC, Créteil, France
- Université Paris Est, École Nationale Vétérinaire d'Alfort, Maisons-Alfort Cedex, France
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9
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Kim F, Bravo PE, Nichol G. What is the use of hypothermia for neuroprotection after out-of-hospital cardiac arrest? Stroke 2015; 46:592-7. [PMID: 25563645 DOI: 10.1161/strokeaha.114.006975] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Francis Kim
- From the Department of Medicine, Harborview Medical Center, University of Washington, Seattle
| | - Paco E Bravo
- From the Department of Medicine, Harborview Medical Center, University of Washington, Seattle
| | - Graham Nichol
- From the Department of Medicine, Harborview Medical Center, University of Washington, Seattle.
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10
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Bravo PE, Kim F. Enhancing approaches to therapeutic hypothermia in patients with sudden circulatory arrest. Curr Atheroscler Rep 2014; 16:451. [PMID: 25216814 DOI: 10.1007/s11883-014-0451-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Cardiac arrest is common and causes substantial morbidity and mortality. Despite advances in prevention and resuscitation, most patients remain unconscious and survival remains poor. Therapeutic hypothermia (32-34 °C) has emerged as a potent neuroprotective modality following resuscitation. In early clinical trials, application of therapeutic hypothermia improved survival in patients with ventricular fibrillation (VF), which led to the recommended use of therapeutic hypothermia for patients resuscitated from VF. However, two recent clinical trials have challenged some assumptions. First, the use of paramedic-initiated rapid infusion of cold crystalloids as a mean to achieve faster cooling rates after resuscitation in patients with and without VF arrest did not improve survival. Second, once patients were admitted to the hospital, targeting their temperature to 33 versus 36 °C for 36 h (in addition to active hyperthermia prevention) after out-of-hospital cardiac arrest did not to change clinical outcomes, suggesting that 36 °C may represent the target temperature instead of temperatures of less than 34 °C.
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Affiliation(s)
- Paco E Bravo
- Division of Cardiology, Department of Medicine, University of Washington, Box 356422, Seattle, WA, 98195, USA,
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Poli S, Purrucker J, Priglinger M, Sykora M, Diedler J, Rupp A, Bulut C, Hacke W, Hametner C. Safety Evaluation of Nasopharyngeal Cooling (RhinoChill®) in Stroke Patients: An Observational Study. Neurocrit Care 2013; 20:98-105. [DOI: 10.1007/s12028-013-9904-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Nadeau M, Micheau P, Robert R, Avoine O, Tissier R, Germim PS, Walti H. Control of rapid hypothermia induction by total liquid ventilation: preliminary results. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2013; 2013:3757-3760. [PMID: 24110548 DOI: 10.1109/embc.2013.6610361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Mild therapeutic hypothermia (MTH) consists in cooling the body temperature of a patient to between 32 and 34 °C. This technique helps to preserve tissues and neurological functions in multi-organ failure by preventing ischemic injury. Total liquid ventilation (TLV) ensures gas exchange in the lungs with a liquid, typically perfluorocarbon (PFC). A liquid ventilator is responsible for ensuring cyclic renewal of tidal volume of oxygenated and temperature-controlled PFC. Hence, TLV using the lung as a heat exchanger and PFC as a heat carrier allows ultra fast cooling of the whole body which can help improve outcome after ischemic injuries. The present study was aimed to evaluate the control performance and safety of automated ultrarapid MTH induction by TLV. Experimentation was conducted using the Inolivent-5.0 liquid ventilator equipped with a PFC treatment unit that allows PFC cooling and heating from the flow of energy carrier water inside a double wall installed on an oxygenator. A water circulating bath is used to manage water temperature. A feedback controller was developed to modulate inspired PFC temperature and control body temperature. Such a controller is important since, with MTH induction, heart temperature should not reach 28 °C because of a high risk of fibrillation. The in vivo experimental protocol was conducted on a male newborn lamb of 4.7 kg which, after anesthetization, was submitted to conventional gas ventilation and instrumented with temperature sensors at the femoral artery, oesophagus, right ear drum and rectum. After stabilization, TLV was initiated with fast automated MTH induction to 33.5 °C until stabilization of all temperatures. MTH could be reached safely in 3 minutes at the femoral artery, in 3.6 minutes at the esophagus, in 7.7 minutes at the eardrum and in 15 minutes at the rectum. All temperatures were stable at 33.5 ± 0.5 °C within 15 minutes. The present results reveal that ultra-fast MTH induction by TLV with Inolivent-5.0 is safe for the heart while maintaining esophageal and arterial temperature over 32.6 °C.
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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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Campos F, Blanco M, Barral D, Agulla J, Ramos-Cabrer P, Castillo J. Influence of temperature on ischemic brain: Basic and clinical principles. Neurochem Int 2012; 60:495-505. [DOI: 10.1016/j.neuint.2012.02.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2011] [Revised: 01/31/2012] [Accepted: 02/04/2012] [Indexed: 12/24/2022]
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Abou-Chebl A, Barbut D. Response to Letter by Albin Regarding Article, “Local Brain Temperature Reduction via Intranasal Cooling With the RhinoChill Device: Preliminary Safety Data in Brain-Injured Patients”. Stroke 2012. [DOI: 10.1161/strokeaha.111.638684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Alex Abou-Chebl
- Department of Neurology
University of Louisville School of Medicine
Louisville, KY (Abou-Chebl)
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16
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Meloni BP, Mastaglia FL, Knuckey NW. Therapeutic applications of hypothermia in cerebral ischaemia. Ther Adv Neurol Disord 2011; 1:12-35. [PMID: 21180567 DOI: 10.1177/1756285608095204] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
There is considerable experimental evidence that hypothermia is neuroprotective and can reduce the severity of brain damage after global or focal cerebral ischaemia. However, despite successful clinical trials for cardiac arrest and perinatal hypoxia-ischaemia and a number of trials demonstrating the safety of moderate and mild hypothermia in stroke, there are still no established guidelines for its use clinically. Based upon a review of the experimental studies we discuss the clinical implications for the use of hypothermia as an adjunctive therapy in global cerebral ischaemia and stroke and make some suggestions for its use in these situations.
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Affiliation(s)
- Bruno P Meloni
- Australian Neuromuscular Research Institute A Block, 1st Floor QEII Medical Centre Nedlands, Western Australia, Australia 6009.
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Abou-Chebl A, Sung G, Barbut D, Torbey M. Local brain temperature reduction through intranasal cooling with the RhinoChill device: preliminary safety data in brain-injured patients. Stroke 2011; 42:2164-9. [PMID: 21680904 DOI: 10.1161/strokeaha.110.613000] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Hypothermia is neuroprotectant but currently available cooling methods are laborious, invasive, and require whole-body cooling. There is a need for less invasive cooling of the brain. This study was conducted to assess the safety and efficacy of temperature reduction of the RhinoChill transnasal cooling device. METHODS We conducted a prospective single-arm safety and feasibility study of intubated patients for whom temperature reduction was indicated. After rhinoscopy, the device was activated for 1 hour. Brain, tympanic, and core temperatures along with vital signs and laboratory studies were recorded. All general and device-related adverse events were collected for the entire hypothermia treatment. RESULTS A total of 15 patients (mean age, 50.3 ± 17.1 years) were enrolled. Brain injury was caused by intracerebral hemorrhage, trauma, and ischemic stroke in equal numbers. Hypothermia was induced for fever control in 9 patients and for neuroprotection/intracranial pressure control in 6. Core temperature, brain temperature, and tympanic temperature were reduced an average of 1.1 ± 0.6°C (range, 0.3 to 2.1°C), 1.4 ± 0.4°C (range, 0.8 to 5.1°C), and 2.2 ± 2°C (range, 0.5 to 6.5°C), respectively. Only 2 patients did not achieve the goal of ≥1°C decrease in temperature. Brain temperature, tympanic temperature, and core temperature reductions were similar between the afebrile and febrile patients. There were no unanticipated adverse events and only 1 anticipated adverse event: hypertension in 1 subject that led to discontinuation of cooling after 30 minutes. There were no nasal complications. CONCLUSIONS Intranasal cooling with the RhinoChill device appears safe and effectively lowers brain and core temperatures. Further study is warranted to assess the efficacy of hypothermia through intranasal cooling for brain-injured patients.
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Affiliation(s)
- Alex Abou-Chebl
- Department of Neurology, University of Louisville School of Medicine, Louisville, KY 40202, USA.
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Maaret C. Response: the use of hypothermia therapy in cardiac arrest survivors. Ther Hypothermia Temp Manag 2011; 1:115-6. [PMID: 24717040 DOI: 10.1089/ther.2011.0011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Castrén Maaret
- Department of Clinical Science and Education, Södersjukhuset Karolinska Institutet , Stockholm, Sweden
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19
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King C, Robinson T, Dixon CE, Rao GR, Larnard D, Nemoto CEM. Brain Temperature Profiles during Epidural Cooling with the ChillerPad in a Monkey Model of Traumatic Brain Injury. J Neurotrauma 2010; 27:1895-903. [DOI: 10.1089/neu.2009.1178] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Christopher King
- Department of Emergency Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | | | - C. Edward Dixon
- Neurosurgery University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Gutti R. Rao
- Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania
| | | | - C. Edwin M. Nemoto
- Department of Neurosurgery, University of New Mexico, Albuquerque, New Mexico
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20
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Castrén M, Nordberg P, Svensson L, Taccone F, Vincent JL, Desruelles D, Eichwede F, Mols P, Schwab T, Vergnion M, Storm C, Pesenti A, Pachl J, Guérisse F, Elste T, Roessler M, Fritz H, Durnez P, Busch HJ, Inderbitzen B, Barbut D. Intra-arrest transnasal evaporative cooling: a randomized, prehospital, multicenter study (PRINCE: Pre-ROSC IntraNasal Cooling Effectiveness). Circulation 2010; 122:729-36. [PMID: 20679548 DOI: 10.1161/circulationaha.109.931691] [Citation(s) in RCA: 271] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Transnasal evaporative cooling has sufficient heat transfer capacity for effective intra-arrest cooling and improves survival in swine. The aim of this study was to determine the safety, feasibility, and cooling efficacy of prehospital transnasal cooling in humans and to explore its effects on neurologically intact survival to hospital discharge. METHODS AND RESULTS Witnessed cardiac arrest patients with a treatment interval <or=20 minutes were randomized to intra-arrest cooling with a RhinoChill device (treatment group, n=96) versus standard care (control group, n=104). The final analysis included 93 versus 101 patients, respectively. Both groups were cooled after hospital arrival. The patients had similar demographics, initial rhythms, rates of bystander cardiopulmonary resuscitation, and intervals to cardiopulmonary resuscitation and arrival of advanced life support personnel. Eighteen device-related adverse events (1 periorbital emphysema, 3 epistaxis, 1 perioral bleed, and 13 nasal discolorations) were reported. Time to target temperature of 34 degrees C was shorter in the treatment group for both tympanic (102 versus 282 minutes, P=0.03) and core (155 versus 284 minutes, P=0.13) temperature. There were no significant differences in rates of return of spontaneous circulation between the groups (38% in treated subjects versus 43% in control subjects, P=0.48), in overall survival of those admitted alive (44% versus 31%, respectively, P=0.26), or in neurologically intact survival to discharge (Pittsburgh cerebral performance category scale 1 to 2, 34% versus 21%, P=0.21), although the study was not adequately powered to detect changes in these outcomes. CONCLUSIONS Prehospital intra-arrest transnasal cooling is safe and feasible and is associated with a significant improvement in the time intervals required to cool patients.
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Affiliation(s)
- Maaret Castrén
- Department of Clinical Science and Education, Karolinska Institutet, Stockholm, Sweden
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21
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Boller M, Lampe JW, Katz JM, Barbut D, Becker LB. Feasibility of intra-arrest hypothermia induction: A novel nasopharyngeal approach achieves preferential brain cooling. Resuscitation 2010; 81:1025-30. [PMID: 20538402 DOI: 10.1016/j.resuscitation.2010.04.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2010] [Revised: 03/16/2010] [Accepted: 04/05/2010] [Indexed: 01/21/2023]
Abstract
AIM In patients with cardiopulmonary arrest, brain cooling may improve neurological outcome, especially if applied prior to or during early reperfusion. Thus it is important to develop feasible cooling methods for pre-hospital use. This study examines cerebral and compartmental thermokinetic properties of nasopharyngeal cooling during various blood flow states. METHODS Ten swine (40+/-4kg) were anesthetized, intubated and monitored. Temperature was determined in the frontal lobe of the brain, in the aorta, and in the rectum. After the preparatory phase the cooling device (RhinoChill system), which produces evaporative cooling in the nasopharyngeal area, was activated for 60min. The thermokinetic response was evaluated during stable anaesthesia (NF, n=3); during untreated cardiopulmonary arrest (ZF, n=3); during CPR (LF, n=4). RESULTS Effective brain cooling was achieved in all groups with a median cerebral temperature decrease of -4.7 degrees C for NF, -4.3 degrees C for ZF and -3.4 degrees C for LF after 60min. The initial brain cooling rate however was fastest in NF, followed by LF, and was slowest in ZF; the median brain temperature decrease from baseline after 15min of cooling was -2.48 degrees C for NF, -0.12 degrees C for ZF, and -0.93 degrees C for LF, respectively. A median aortic temperature change of -2.76 degrees C for NF, -0.97 for LF and +1.1 degrees C for ZF after 60min indicated preferential brain cooling in all groups. CONCLUSION While nasopharyngeal cooling in swine is effective at producing preferential cerebral hypothermia in various blood flow states, initial brain cooling is most efficient with normal circulation.
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Affiliation(s)
- Manuel Boller
- Center for Resuscitation Science, Department of Emergency Medicine, School of Medicine, University of Pennsylvania, Philadelphia, PA 19146, United States.
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22
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Busch HJ, Eichwede F, Födisch M, Taccone FS, Wöbker G, Schwab T, Hopf HB, Tonner P, Hachimi-Idrissi S, Martens P, Fritz H, Bode C, Vincent JL, Inderbitzen B, Barbut D, Sterz F, Janata A. Safety and feasibility of nasopharyngeal evaporative cooling in the emergency department setting in survivors of cardiac arrest. Resuscitation 2010; 81:943-9. [PMID: 20627524 DOI: 10.1016/j.resuscitation.2010.04.027] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 04/13/2010] [Accepted: 04/28/2010] [Indexed: 10/19/2022]
Abstract
AIM Mild therapeutic hypothermia improves survival and neurologic recovery in primary comatose survivors of cardiac arrest. Cooling effectivity, safety and feasibility of nasopharyngeal cooling with the RhinoChill device (BeneChill Inc., San Diego, USA) were determined for induction of therapeutic hypothermia. METHODS Eleven emergency departments and intensive care units participated in this multi-centre, single-arm descriptive study. Eighty-four patients after successful resuscitation from cardiac arrest were cooled with nasopharyngeal delivery of an evaporative coolant for 1h. Subsequently, temperature was controlled with systemic cooling at 33 degrees C. Cooling rates, adverse events and neurologic outcome at hospital discharge using cerebral performance categories (CPC; CPC 1=normal to CPC 5=dead) were documented. Temperatures are presented as median and the range from the first to the third quartile. RESULTS Nasopharyngeal cooling for 1h reduced tympanic temperature by median 2.3 (1.6; 3.0) degrees C, core temperature by 1.1 (0.7; 1.5) degrees C. Nasal discoloration occurred during the procedure in 10 (12%) patients, resolved in 9, and was persistent in 1 (1%). Epistaxis was observed in 2 (2%) patients. Periorbital gas emphysema occurred in 1 (1%) patient and resolved spontaneously. Thirty-four of 84 patients (40%) patients survived, 26/34 with favorable neurological outcome (CPC of 1-2) at discharge. CONCLUSIONS Nasopharyngeal evaporative cooling used for 1h in primary cardiac arrest survivors is feasible and safe at flow rates of 40-50L/min in a hospital setting.
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Affiliation(s)
- H-J Busch
- Albert Ludwigs University Freiburg, Department of Cardiology and Angiology, Freiburg i. Br., Germany
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23
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Schratter A, Weihs W, Janata A, Bayegan K, Holzer M, Sterz F, Behringer W. Surface vs. aortic flush cooling during cardiac arrest in pigs. Acta Anaesthesiol Scand 2010; 54:206-11. [PMID: 19735492 DOI: 10.1111/j.1399-6576.2009.02113.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND To investigate the feasibility and efficacy of earlier induction of hypothermia already during the 'no-flow' period of cardiac arrest with non-invasive surface cooling or invasive aortic flush cooling. METHODS This was a prospective randomized experimental study that included 14 pigs, Large White breed (30-38 kg), with ventricular fibrillation cardiac arrest plus blanket surface and an invasive cold saline flush cooling. The endpoint was a decline in brain temperature (T(br)) at 35 min after cardiac arrest. RESULTS With surface cooling, T(br) decreased from 38.7+/-0.2 degrees C to 37.4+/-0.8 degrees C (P=0.02) and with invasive cooling T(br) decreased from 38.8+/-0.13 degrees C to 19.0+/-2.8 degrees C within 216+/-23 s (P=0.02) and increased back to 33.0+/-0.6 degrees C at 35 min of cardiac arrest (P=0.02 vs. T(br) at 15 min, P=0.002 vs. T(br) at 35 min in the surface cooling groups). CONCLUSION Invasive cooling by aortic flush with cold saline rapidly induces deep cerebral hypothermia, whereas non-invasive surface cooling only marginally decreases brain temperature.
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Affiliation(s)
- A Schratter
- Department of Emergency Medicine and Core Unit for Biomedical Research, Medical University of Vienna, Wien, Austria
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25
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Tang XN, Yenari MA. Hypothermia as a cytoprotective strategy in ischemic tissue injury. Ageing Res Rev 2010; 9:61-8. [PMID: 19833233 DOI: 10.1016/j.arr.2009.10.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2009] [Revised: 10/02/2009] [Accepted: 10/06/2009] [Indexed: 12/19/2022]
Abstract
Hypothermia is a well established cytoprotectant, with remarkable and consistent effects demonstrated across multiple laboratories. At the clinical level, it has recently been shown to improve neurological outcome following cardiac arrest and neonatal hypoxia-ischemia. It is increasingly being embraced by the medical community, and could be considered an effective neuroprotectant. Conditions such as brain injury, hepatic encephalopathy and cardiopulmonary bypass seem to benefit from this intervention. It's role in direct myocardial protection is also being explored. A review of the literature has demonstrated that in order to appreciate the maximum benefits of hypothermia, cooling needs to begin soon after the insult, and maintained for relatively long period periods of time. In the case of ischemic stroke, cooling should ideally be applied in conjunction with the re-establishment of cerebral perfusion. Translating this to the clinical arena can be challenging, given the technical challenges of rapidly and stably cooling patients. This review will discuss the application of hypothermia especially as it pertains to its effects neurological outcome, cooling methods, and important parameters in optimizing hypothermic protection.
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Affiliation(s)
- Xian N Tang
- Department of Neurology, University of California, San Francisco, CA 94121, USA
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Christian E, Zada G, Sung G, Giannotta SL. A review of selective hypothermia in the management of traumatic brain injury. Neurosurg Focus 2008; 25:E9. [DOI: 10.3171/foc.2008.25.10.e9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Traumatic brain injury (TBI) remains a significant cause of morbidity and death in the US and worldwide. Resuscitative systemic hypothermia following TBI has been established as an effective neuroprotective treatment in multiple studies in animals and humans, although this intervention carries with it a significant risk profile as well. Selective, or preferential, methods of inducing cerebral hypothermia have taken precedence over the past few years in order to minimize systemic adverse effects. In this report, the authors explore the current methods available for inducing selective cerebral hypothermia following TBI and review the literature regarding the results of animal and human trials in which these methods have been implemented.
Methods
A search of the PubMed archive (National Library of Medicine) and the reference lists of all relevant articles was conducted to identify all animal and human studies pertaining to the use of selective brain cooling, selective hypothermia, preferential hypothermia, or regional hypothermia following TBI.
Results
Multiple methods of inducing selective cerebral hypothermia are currently in the experimental phases, including surface cooling, intranasal selective hypothermia, transarterial or transvenous endovascular cooling, extraluminal vascular cooling, and epidural cerebral cooling.
Conclusions
Several methods of conferring preferential neuroprotection via selective hypothermia currently are being tested. Class I prospective clinical trials are required to assess the safety and efficacy of these methods.
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Affiliation(s)
| | | | - Gene Sung
- 2Neurology, Keck School of Medicine, University of Southern California, Los Angeles, California
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Campbell K, Meloni BP, Knuckey NW. Combined magnesium and mild hypothermia (35 degrees C) treatment reduces infarct volumes after permanent middle cerebral artery occlusion in the rat at 2 and 4, but not 6 h. Brain Res 2008; 1230:258-64. [PMID: 18644354 DOI: 10.1016/j.brainres.2008.06.110] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Revised: 06/25/2008] [Accepted: 06/27/2008] [Indexed: 01/10/2023]
Abstract
BACKGROUND AND PURPOSE Using transient focal and global cerebral ischemia models in the rat, we have previously shown that MgSO4 is not neuroprotective unless it is combined with mild hypothermia. This study establishes a therapeutic time window for combined MgSO4 and mild hypothermia treatment after permanent middle cerebral artery occlusion (MCAO). METHODS Rats were subjected to permanent intraluminal thread MCAO and animals were treated 2, 4 or 6 h after ischemia with a MgSO4 infusion (360 micromol/kg, then 120 micromol/kg/h) and mild hypothermia (35 degrees C) or with vehicle for 24 h. At the 2 h time point, treatment with hypothermia alone and MgSO4 alone were also assessed. Infarct volumes were measured 48 h after MCAO induction. RESULTS After permanent MCAO, combined MgSO4 and hypothermia treatment reduced infarct volumes by 54% at 2 h (P = 0.048) and by 39% at 4 h (P = 0.012), but there was no treatment effect detected at 6 h or in the hypothermia alone or MgSO4 alone groups. CONCLUSIONS These findings support our earlier work highlighting the neuroprotective effect of MgSO4 when combined with mild hypothermia, even when treatment is delayed by several hours.
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Affiliation(s)
- Kym Campbell
- Centre for Neuromuscular and Neurological Disorders/University of Western Australia, Australian Neuromuscular Research Institute, Department of Neurosurgery/Sir Charles Gairdner Hospital, Nedlands, WA, Australia
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