The role of carbon dioxide in acute brain injury

Abstract

Carbon dioxide is a common gas in the air which has been widely used in medical treatment. A carbon dioxide molecule consists of two oxygen atoms and one carbon atom through a covalent bond. In the body, carbon dioxide reacts with water to produce carbonic acid. In healthy people, carbon dioxide is maintained within a narrow range (35–45 mmHg) by physiological mechanisms. The role of hypocapnia (partial pressure of carbon dioxide < 35 mmHg) and hypercapnia (partial pressure of carbon dioxide > 45 mmHg) in the nervous system is intricate. Past researches mainly focus on the effect of hypocapnia to nerve protection. Nevertheless, Hypercapnia seems to play an important role in neuroprotection. The mechanisms of hypocapnia and hypercapnia in the nervous system deserve our attention. The purpose of this review is to summarize the effect of hypocapnia and hypercapnia in stroke and traumatic brain injury.

A Função Do Dióxido De Carbono Na Lesão Cerebral Aguda: Revisão Integrativa

“…Por outro lado, a hipercapnia grave parece estar associada a efeitos adversos, como aumento do edema cerebral e risco de hemorragia cerebral, destacando a importância de uma abordagem cautelosa ao gerenciamento dos níveis de CO2 em pacientes com lesões cerebrais agudas. (Deng et al, 2020) Essa dualidade de efeitos destaca a complexidade da resposta do SNC à hipercapnia e ressalta a necessidade de uma compreensão mais aprofundada dos mecanismos subjacentes e dos limites seguros dos níveis de CO2. Além disso, a pesquisa atual sugere que os efeitos da hipercapnia podem variar dependendo de fatores como a gravidade da lesão cerebral, a idade do paciente e o tempo de exposição à hipercapnia.…”

Perioperative management of adults with traumatic brain injury

“…PaCO 2 levels which rise above normal (5.2kPa) result in cerebral vasodilatation and an increase in ICP. PaCO 2 values which are uncontrolled may increase the risk of cerebral haemorrhage (Deng et al 2020).…”

Neuroprotective Potential of Mild Uncoupling in Mitochondria. Pros and Cons

“…In parallel with the activation of mitochondrial respiration, there is a proportional increase in the formation of CO 2 , which, in addition to being one of the main factors in maintaining intracellular pH homeostasis, regulates several integral intracellular processes [20,[40][41][42][43][44]. Carbon dioxide exerts a direct neuroprotective effect since mild hypercapnia during hypoxia-ischemia provides a long-lasting motor function, as well as neurologic protection for immature brains [45] or traumatic brain injury and stroke (see for review [46]) possibly through increasing cerebral blood flow during hypoxia. Bicarbonate transporters in neural cells were also shown to be protective against ischemia [47][48][49].…”