Regional cooling for reducing brain temperature and intracranial pressure

Abstract

-Objective:To evaluate the effectiveness of regional cooling for reducing brain temperature (BrTe) and intracranial pressure (ICP) in patients where conventional clinical treatment has failed. Method: Regional cooling was carried out using ice bags covering the area of the craniectomy (regional method) in 23 patients. The BrTe and ICP were determined using a fiber optic sensor. Thirteen patients (56.52%) were female. The ages ranged from 16 to 83 years (mean of 48.9). The mean APACHE II score was 25 points (11-35). The patients were submitted, on mean, to 61.7 hours (20-96) of regional cooling. Results: There was a significant reduction in mean BrTe (p<0.0001-from 37.1ºC to 35.2ºC) and mean ICP (p=0.0001-from 28 mmHg to 13 mmHg). Conclusion: Our results suggest that mild brain hypothermia induced by regional cooling was effective in the control of ICP in patients who had previously undergone decompressive craniectomy.KEy wORds: intracranial hypertension, intracranial pressure, cerebral hypothermia, brain edema, brain injuries. Resfriamento cerebral regional para redução da temperatura e pressão intracranianaResumo -Objetivo: Avaliar a eficácia do resfriamento regional na redução da temperatura cerebral (TeCe) e pressão intracraniana (PIC) após falha das medidas clínicas convencionais de tratamento. Método: O resfriamento cerebral foi realizado com bolsas com gelo, colocadas sobre a área de craniectomia (método regional) em 23 doentes. A TeCe e PIC foram verificadas com sensor de fibra óptica. Treze (56,52%) eram do sexo feminino. A idade variou de 16 a 83 anos (média 48,96). A pontuação média no índice APACHE II foi 25 pontos . Os doentes foram submetidos, em média, a 61,7 horas (20-96) de resfriamento regional. Resultados: Houve uma redução significativa da TeCe média (p<0,0001-de 37,1ºC para 35,2ºC) e da PIC média (p=0,0001-de 28 mmHg para 13 mmHg). Conclusão: Nossos resultados sugerem que o resfriamento regional foi eficaz no controle da PIC nos doentes submetidos, previamente, a craniectomia descompressiva.PAlAvRAs-CHAvE: hipertensão intracraniana, pressão intracraniana, hipotermia induzida, edema encefálico, traumatismos encefálicos.

Selective Brain Cooling after Traumatic Brain Injury: Effects of Three Different Cooling Methods—Case Report

“…Unfortunately, the authors did not report the course of core temperature during the 12-hour cooling period. 24 These data may well be in accordance with our finding that brain and core temperature both decrease by surface cooling and finally maintain a temperature difference of 0.8°C. In addition, ICP was reported to decrease a similar degree as observed in our case.…”

Temperatures Achieved in Human and Canine Neocortex During Intraoperative Passive or Active Focal Cooling

“…The results of our experiments involving direct brain cooling agree with those of a previous theoretical simulation and with several clinical trials of localized external head cooling in patients with traumatic brain injuries (Zhu and Diao, 2001;Wang et al, 2004;Forte et al, 2009;Harris et al, 2009). In those trials, external cooling was applied with cooling helmets or ice packs to achieve a comparable change in temperature within the brain of about 2°C.…”

Cerebral hemodynamics: concepts of clinical importance

“…In the injured brain, hyperthermia increases metabolic expenditure, blood flow, glutamate-induced neurotoxicity, neutrophil activity, and reactive oxygen species 63 . These events may further enhance the vulnerability of the brain to secondary pathogenic events, thereby exacerbating brain swelling and neuronal damage 64 . Glucose utilization in most regions of the brain changes by approximately 5 to 10% for every degree Celsius change in body temperature, underscoring the importance of preventing hyperthermia in the acute phase of severe brain injury.…”