Changes in Blood Pressure and Heart Rate during Decompressive Craniectomy

Objective : Rapid increase in intracranial pressure (ICP) can result in hypertension, bradycardia and apnea, referred to as the Cushing phenomenon. During decompressive craniectomy (DC), rapid ICP decreases can cause changes in mean atrial blood pressure (mABP) and heart rate (HR), which may be an indicator of intact autoregulation and vasomotor reflex. Methods : A total of 82 patients who underwent DC due to traumatic brain injury (42 cases), hypertensive intracerebral hematoma (19 cases), or major infarction (21 cases) were included in this prospective study. Simultaneous ICP, mABP, and HR changes were monitored in one minute intervals during, prior to and 5-10 minutes following the DC. Results : After DC, the ICP decreased from 38.1 +/- 16.3 mmHg to 9.5 +/- 14.2 mmHg (p<0.001) and the mABP decreased from 86.4 +/- 14.5 mmHg to 72.5 +/- 11.4 mmHg (p<0.001). Conversly, overall HR was no significantly changed in HR, which was 100.1 +/- 19.7 rate/min prior to DC and 99.7 +/- 18.2 rate/min (p=0.848) after DC. Notably when the HR increased after DC, it correlated with a favorable outcome (p<0.001), however mortality was increased (p=0.032) when the HR decreased or remained unchanged. Conclusion : In this study, ICP was decreased in all patients after DC. Changes in HR were an indicator of preserved autoregulation and vasomotor reflex. The clinical outcome was improved in patients with increased HR after DC.