Yes, this is reasonable. While it may seem somewhat counterintuitive, we need to try augmenting her BP with a systemic, IV vasopressor, like norepinephrine. The hope is that she has impaired imperfusion that can be improved, and that she hasn't yet progressed to DCI with infarction. The 2023 AHA/ASA guidelines for aSAH do recommend reactive (not prophylactic) BP augmentation for symptomatic vasospasm. The exact MAP target varies by local practice patterns. You could try raising the goal MAP to > 85mmHg first. If the patient improves, then that's an adequate target right there. If not, you could consider raising the goal even further, to 100mmHg, and reassessing for clinical benefit. Others would advocate for starting with this higher target of > 100mmHg first. There's no clear answer.
With our patient here, there's a slight wrinkle that is important to recognize. Two, actually. For one, augmenting BP increases cardiac afterload. This is fine if her LV function is adequate. If it's diminished, though, then that's a problem, as raising afterload will reduce her cardiac output, which would yield a counterproductive result of reduced systemic and cerebral perfusion. For this patient, her LV systolic function was mildly reduced early in the course. We should repeat a TTE. If her LV function has recovered, then we're good to proceed with BP augmentation. If it's stably mildly impaired, we could choose to be more modest with our MAP goal and closely monitor for signs/symptoms of shock, reassessing with this titration approach to see if we can even go up further. If it's worse, then we need to avoid BP augmentation with vasopressors entirely and choose another option.*
The second wrinkle is that the patient actually has an unsecured aneurysm-- the small right ophthalmic artery one. Luckily, the larger, presumed ruptured aneurysm at the basilar tip was confidently secured. Augmenting her BP may raise the risk of rupture of this unsecured aneurysm. However, given the patient's poor clinical exam now, and the small size of this other, somewhat incidental aneurysm, it's reasonable to say that the risk/benefit profile favors BP augmentation with continued close monitoring.
Another reasonably correct answer choice was to contact neuroIR for consideration of angioplasty or IA vasodilator injection (e.g. milrinone, nicardipine, nitroglycerin, verapamil). Whether this or BP augmentation happens first (realistically, you'd augment BP while awaiting their decision anyway) is dependent on local practice patterns. Anatomical considerations, such as the presence of dissections, may preclude endovascular rescue therapy. Some interventionalists may prefer a trial of medical management first.
* You could argue that IV milrinone gtt would be a better fit here. As an inodilator, it could achieve cerebral vasodilation while also improving cardiac contractility. There isn't strong data for milrinone. (The best data we have is from MILRISPASM, which was a non-randomized prospective study that suggested benefit, but the doses used were very very high and many couldn't tolerate this.) If we did go this route, then the vasodilator effect would have to also be counteracted with a vasopressor to ensure adequate systemic perfusion.
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