Fig. 5

Effect on cerebral blood flow caused by augmentation of PaCO₂. A male in his 30s suffered a traffic accident. Initial CT scan demonstrated acute subdural hematoma. Increased PaCO₂ could stimulate the vasodilation cascade in the brain. As a result of an increase in PaCO₂, the brain vasculature goes through vasodilation, with a subsequent increase in cerebral blood flow (and cerebral blood volume), leading to increased ICP. Physicians would be able to detect this from increased SjO₂ in the clinical setting. Resp. respiration, SAP systemic arterial pressure, ICP intracranial pressure, SjO ₂ jugular bulb oxygen saturation, CPP cerebral perfusion pressure. Data were obtained from brain injury patient monitored at our hospital in the 1990s