CO2 and indomethacin vasoreactivity in patients with cranial trauma

: The purpose of this study was to compare the effect of hyperventilation and indomethacin on cerebral circulation, metabolism and systemic and intracerebral pressures in patients with severe head injury. Fourteen moderately (PaCO2 = 4.05 kPa) hyperventilated patients with median [CP = 14.8 mmHg entered the study. Cerebral blood flow (CBF), intracranial pressure (ICP), arteriovenous difference of oxygen (AVDO2) and lactate (AVdL) and oxygen saturation in the jugular bulb (SvjO2) were measured before and after hyperventilation and after a bolus dose of indomethacin (30 mg). During hyperventilation CBF decreased by 11.8%/kPa and ICP decreased by 3.8 mmHg. AVDO2 increased by 34.0%/kPa. After indomethacin CBF decreased by 14.7% and ICP decreased by 4.3 mmHg. AVDO2 increased with 27.8%. No changes in median SvjO2 and AVdL were observed after the two treatments. The risk of cerebral ischaemia seems identical after the two treatments. No correlations between the effects of the two treatments on CBF, ICP and AVDO2 were found. These results suggest that indomethacin and hyperventilation might act independently or in a complementary fashion in the treatment of patients with severe head injury.