Cerebral perfusion and cerebrovascular pressure reactivity

A 4-year-old female underwent multimodality neurologic monitoring with intraparenchymal intracranial pressure monitoring. The pressure reactivity index was used to evaluate cerebrovascular pressure reactivity efficiency. When plotting the pressure reactivity index over cerebral perfusion pressure in an epoch of 8 hours, there is a parabolic curve, suggesting that the optimal cerebral perfusion pressure for cerebrovascular pressure reactivity efficiency (CPPOpt) is approximately 64.8 mmHg, with an estimated lower limit of cerebrovascular pressure reactivity (LL) at approximately 48.9 mmHg and an upper limit of cerebrovascular pressure reactivity (UL) at approximately 80.8 mmHg. In the fourth row from the top, the green band represents the theoretical range of LL and UL, the red line represents real-time calculated CPPOpt, and the yellow line represents the patient’s actual cerebral perfusion pressure values. (Contributed by Dr. Brian Appavu.)