急性颅脑损伤救治:不能忽视的脑血流调节功能

Management of acute brain injury:importance of cerebral blood flow regulation

脑血流调节依赖于心血管、呼吸和神经生理学之间复杂的相互作用,以保障脑代谢供需的匹配,保护大脑免受缺血或充血损伤。其调节机制包括心输出量调节、脑血管自动调节、脑血管二氧化碳反应性、神经调节以及神经血管耦联。急性颅脑损伤患者脑损伤机制复杂多样,涉及脑动脉压、脑血流、脑代谢的紊乱。这些参数的紊乱,导致了其脑血流调节功能损伤,而紊乱的脑血流调节功能加重了脑损伤。监测脑血流调节功能是急性颅脑损伤患者救治的重要环节。脑血流调节功能可实现床旁连续动态监测。在临床工作中,优化脑代谢及脑电活动,优化心输出量、保证脑血流充足性,通过脑血流自动调节寻找合适的脑灌注压,优化二氧化碳分压提供最优血管储备等治疗是急性颅脑损伤脑保护不容忽视的核心原则。

Regulation of the cerebral blood flow relies on the complex interplay between cardiovascular,respiratory,and neural physiology.The precise regulation of cerebral blood flow is critical for maintenance of constant nutrient and oxygen supply to the brain,protecting the brain from ischemia or hyperemia.The mechanism of regulation of cerebral blood flow,including cardiac output regulation,cerebral autoregulation,carbon dioxide reactivity,neuroregulation,and neurovascular coupling,is multifactorial,but all of them must act on the cerebral circulation.The pathophysiology of acute brain injury is complex and diverse,which involves the disorder of cerebral arterial pressure,cerebral blood flow,and cerebral metabolism.The disorder of these parameters leads to the impairment of cerebral blood flow regulation,thus aggravating the brain injury.Monitoring regulation of cerebral blood flow is important in the treatment of acute brain injury.Regulation of cerebral blood flow can be realized by continuous dynamic bedside monitoring.The core principles for the treatment of acute brain injury are optimizing cardiac output,ensuring cerebral perfusion,optimizing cerebral metabolism and neuronal activity,finding appropriate cerebral arterial pressure to match cerebral blood flow through cerebral autoregulation,and optimizing pressure of arterial carbon dioxide to provide optimal vascular reserve.