[Central and cerebral hemodynamics during general anesthesia in intracranial interventions in a sitting position].

Cerebral bloodflow and central hemodynamics were studied during general anesthesia in patients with tumors of the posterior cranial fossa operated on in a sitting posture. A sitting posture during general anesthesia is conductive to a marked reduction of the stroke volume and linear velocity of the cerebral bloodflow, this creating a risk of cerebral tissue ischemia under conditions of intracranial hypertension and a hardly adequate short-term compensatory increase of the total vascular resistance and "paradoxical" increase of cerebrovascular tone. Since the neurogenous mechanisms of cerebral bloodflow autoregulation are disordered during anesthesia, one should admit that stabilization of central hemodynamics at all stages of anesthesia is a most important condition for optimizing brain tissue perfusion.