Cerebral Perfusion Goals During Cardiopulmonary Bypass—The Goldilocks Effect

We read with great interest the article by Brown et al¹ in this issue of JAMA Surgery on the effects of mean arterial pressure (MAP) management strategies during cardiopulmonary bypass on postoperative delirium. This nested randomized clinical trial compared the use of cerebral autoregulation with transcranial Doppler to target MAP for cardiopulmonary bypass at the lower threshold of cerebral autoregulation with the standard of care in patients at high risk for neurologic complications. The authors emphasize the importance of targeting MAP using cerebral blood flow monitoring, because cerebral hypoperfusion and hyperemia are individual phenomena that can both occur during cardiopulmonary bypass and either may result in postoperative delirium if cerebral perfusion is not “just right.”