ANESTHESIOLOGY FAST REVIEW

ANESTHESIOLOGY_FAST_REVIEWKAPAK1-0-25

NEUROPHYSIOLOGY

Burak Nalbant

Ankara Yıldırım Beyazıt University, Faculty of Medicine, Department of Anesthesiology and Reanimation, Ankara, Türkiye

Nalbant B. Neurophysiology. In: Kazancı D, editor. Anesthesiology Fast Review. 1st ed. Ankara: Türkiye Klinikleri; 2025. p.23-34.

ABSTRACT

  • Understanding neurophysiological processes during anesthesia is crucial for preventing cerebral complications and ensuring patient safety.
  • The increasing elderly population and the high prevalence of cerebral diseases in the perioperative period underscore the critical role of neurophysiological knowledge in anesthesia practice.
  • The circle of Willis ensures cerebral blood flow by distributing blood through its vascular network; cerebrospinal fluid (CSF) provides mechanical protection, metabolic support, and chemical homeostasis; and the blood-brain barrier (BBB) regulates selective permeability to protect the brain from harmful substances.
  • The brain consumes 20% of the body’s oxygen supply, with glucose as its primary energy source. Even a brief interruption (3–5 minutes) of cerebral blood flow can lead to irreversible cellular damage.
  • Cerebral blood flow (CBF) is regulated according to metabolic demands and maintained through autoregulatory mechanisms. However, factors such as hypertension, hypocapnia, and anesthetic agents can impair this regulation.
  • Intracranial pressure (ICP) is determined by the balance among brain tissue, blood, and CSF; an increase in ICP can result in brain herniation, a life-threatening condition. Cerebral ischemia occurs due to reduced cerebral perfusion and leads to neuronal cell death.
  • Energy depletion, excitotoxicity, tissue acidosis, and neuroinflammation are key contributors to ischemic brain injury.
  • The primary neuroprotective strategies include optimizing cerebral perfusion, reducing metabolic demand, and preventing secondary injury. Hypothermia, glycemic control, and seizure prophylaxis are among the most effective protective interventions.
  • Barbiturates, propofol, and volatile anesthetics may exert neuroprotective effects by reducing cerebral metabolic rate and oxygen consumption.
  • The maintenance and precise management of physiological parameters are more critical than the choice of anesthetic agent in ensuring optimal patient outcomes.

Keywords: Neurophysiology; Cerebrovascular circulation; Hypoxia-ischemia; Brain

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