gms | German Medical Science

Objective: Severe aneurysmal subarachnoid hemorrhage (SAH) may lead, primarily or during the time course, to the necessity of decompressive craniectomy (DC) in order to treat refractory elevated intracranial pressure (ICP). In some patients, adequate deep sedation, as one part of conservative treatment of elevated ICP, can’t be achieved. Recent investigations suggest that inhalative sedation protocols might not be as detrimental as considered before, and might be an option in this clinical setting.

Method: We treated 5 patients with severe SAH (Hunt & Hess 3–5, Fisher 3), all suffering from elevated ICP refractory to conservative therapeutic regime, who underwent DC. Difficulties in reaching the targeted deep sedation (Richmond Aggitation Sedation Scale (RASS) -5) with high doses of i.v. sedatives lead to the start of inhalational sedation with Isoflurane in combination with opioids.

Results: Deep sedation (Mean-Fet 0,85%) was achieved in all patients within seconds after initiation of the inhalative sedation. ICP remained stable comparing the status one hour before onset of Isoflurane sedation (1) to the status 6 (2), and 12 hours (3) afterwards (mean ICP (1) 14,2 mmHg; (2) 13 mmHg; (3) 9,4 mmHg). The mean duration of application was 8 (±5) days. Cerebral perfusion pressure (CPP) could be maintained in our therapeutical range above 70mmHg without the need for extended vasopressor usage.

Conclusions: In a setting of severe SAH and critically elevated ICP with the need for aggressive multimodal therapy, including DC and deep sedation, inhalative Isoflurane was safely applied. Our sedation goal was easily achieved and undesirable effects like a critical rise in ICP were not observed. Further investigations are warranted, since Isoflurane has better controllable pharmacokinetics, no accumulation of clinical importance and neuroprotective effects in animal models as well.