The Specific Features of Oxygen Transport in the Acute Period of Ischemic Stroke

Abstract

Objective: to study the oxygen transport system in the acute period of ischemic stroke (IS). Subjects and methods. Central hemodynamics and the oxygen transport system were studied, intracranial pressure was measured, cerebral perfusion pressure was calculated and neurophysiological and X-ray studies were conducted in 36 patients in the first 7 days of IS. Results. In the first 5 study days, circulatory hypoxia developed due to evolving hypodynamic circulation. Later on, the situation was deteriorated by arterial hypoxemia due to acute respiratory distress syndrome and increased pulmonary shunting. Simultaneously on days 5 and 7, there were reductions in the oxygen consumption index and oxygen extraction coefficient, which was due to vasoconstriction, higher blood flow velocity, and lower oxygen extraction. Neurophysiological evidence was used to diagnose sub- and decompensation of stem structural functions. Conclusion. Vasoconstriction leads to the development of circulatory hypoxia. Thus, the early period of ischemic stroke is marked by the decreased oxygen delivery index due to the development of hypodynamic circulation. This is further attended by pulmonary complications and microcircula-tory disorders. On day 5 of the acute period, noncardiogenic pulmonary edema developed and pulmonary shunt increased, by worsening hypoxia. Impaired function of stem structures due to their damage, as evidenced by clinical, neurophysiologi-cal, radiological, and autoptic studies, is one of the causes of hemodynamic disorders, thereby impairing the oxygen transport system. Key words: acute cerebral circulatory disorder, oxygen transport system.