Response to: “Precise Clinical Outcome in High-Grade Aneurysmal Subarachnoid Hemorrhage: Brain Oxygenation Matters!”

By Teodor Svedung Wettervik & Per Enblad
First Online:
27 April 2021

We thank Dr. Schmitt and colleagues for finding our original article “Temporal dynamics of ICP, CPP, PRx, and CPPopt in high-grade aneurysmal subarachnoid hemorrhage and the relation to clinical outcome” [1] interesting and for the important comments.
First, pCO2 is a relevant factor to consider because it is an important modulator of cerebral blood flow (CBF) in general and after acute brain injury. Taking into consideration the risk of developing cerebral vasospasm after aneurysmal subarachnoid hemorrhage (aSAH), our management protocol targets normoventilation (pCO2 within 5.5–6.0 kPa), and hyperventilation should generally be avoided so not to induce and/or worsen vasospasm [1]. It is therefore unlikely that not including pCO2 in our analyses biased the results significantly. Regarding the problem that sedation may limit the possibility to assess the neurological status of mechanically ventilated patients, this can be overcome by performing frequent neurological wake-up tests to detect neurological deterioration in time. Wake-up tests are performed approximately six times per day in patients with aSAH at our neurointensive care unit.

Read the full article here.