Hemodynamic changes during surgical decompression in traumatic brain injury patients.

Objective To understand the hemodynamic changes that occur with surgical decompression of lesions caused by traumatic brain injury. Methods In this prospective, observational study, patients with traumatic brain injury requiring craniotomy within 48 hours of injury were recruited. Cardiac index (CI), stroke volume index, stroke volume variation, systemic vascular resistance index (SVRI), heart rate, and mean arterial pressure were monitored throughout surgery using a FloTrac transducer. Standard anesthetic and surgical regimens were followed. Results Hemodynamic data in 107 patients were compared before skin incision and after hematoma decompression (comparable anesthetic state). There was a significant increase in CI and stroke volume index and a decrease in SVRI and mean arterial pressure following surgical decompression. On subgroup analysis based on preincision CI, the changes were similar in patients with low and normal CI, whereas in patients with high CI, SVRI did not decrease significantly. High preincision CI with no change in SVRI with decompression was associated with poor neurologic outcome at discharge. Conclusions In patients with TBI, surgical decompression leads to an increase in CI and a decrease in mean arterial pressure owing to a decrease in SVRI in patients with preincision low or normal cardiac output. These changes were not seen in patients with preincision high CI, and such patients had a poor neurologic outcome.