It remains unclear how the timing of in-hospital calcium channel blockers (CCBs; Nimodipine or Cardene) initiation effects the risk for vasospasm after aneurysmal subarachnoid hemorrhage (aSAH).

After aSAH patients are given CCB to prevent vasospasm which is associated with worsened outcomes.

This retrospective cohort study included adults (≥ 18) with aSAH at a Comprehensive Stroke Center (1/18-11/21) who were taking the following prehospital antihypertensives: CCBs, Angiotensin-converting enzyme (ACE) inhibitors or Angiotensin II receptor blockers (ARBs). Comparisons were made between those who received vasospasm prevention (‘in-hospital CCBs’) ≤ 1 hour of arrival to those who received in-hospital CCBs > 1 hour from arrival.  Outcomes included: vasospasm, length of stay (LOS), and death.

There were 252 patients, 18% were taking prehospital antihypertensives. Of those 80% received in-hospital CCBs: 35% ≤ 1 hour of arrival, 65% received them > 1 hour of arrival. Patients were similar in their baseline characteristics. The time to in-hospital CCBs was significantly longer for patients who had a vasospasm, 1.3 vs 5.2 h, p=0.02. Those who received in-hospital CCBs ≤ 1 hour of arrival experienced a significantly lower vasospasm rate (0% vs. 38%, p=0.01), LOS (11 vs 22, p=0.006), and death rate (0% vs 38%, p=0.01) than among those who did not. These results were not replicated for patients who were not on prehospital antihypertensives; the timing to in-hospital CCB initiation had no effect on vasospasm (p=0.18), death (p=0.28), or LOS (p=0.08) for patients not on prehospital antihypertensives.

While larger studies are needed, this study showed that those on prehospital CCBs, ACE-inhibitors, or ARBs, receipt of in-hospital CCBs ≤ 1 hour of arrival significantly reduced the vasospasm rate, HLOS, and death rate. Reducing disruption times in prehospital antihypertensive treatment through in-hospital CCB receipt ≤ 1 hour of arrival, may prevent worsened outcomes.