Improvement in Sonographic Vasospasm Following Intravenous Milrinone in a Subarachnoid Hemorrhage Patient with Normal Cardiac Function

Cerebral vasospasm and delayed cerebral ischemia are well-known complications of an aneurysmal subarachnoid hemorrhage (aSAH), generally occurring days to weeks after hemorrhagic ictus. Management strategies for these complications are controversial and vary in efficacy. There is a growing interest in supporting the use of intravenous (IV) milrinone to manage vasospasm. A 31-year-old male presented to the hospital after being found down outside his home. Computed tomography (CT) of the head and subsequent CT angiogram revealed a Fisher Grade 4 aneurysmal subarachnoid hemorrhage (aSAH). Six hours after admission, he became hypotensive and his neurological examination declined. A repeat CT head showed a new, left frontoparietal intracerebral hemorrhage (ICH) along with increasing SAH. He was stabilized with vasopressors and underwent emergent decompressive hemicraniectomy with subsequent clipping of the aneurysm. Approximately one week later, transcranial Doppler (TCD) showed increasing mean flow velocities in the bilateral anterior and middle cerebral arteries consistent with cerebral vasospasm. He was treated with intravenous milrinone. Repeat TCD 6.5 hours after the initial TCD showed improved mean flow velocities. His cardiac function by echocardiogram assessment was normal. The decrease in TCD velocity following treatment with milrinone indicates an improvement in the cerebral vasospasm regardless of cardiac output in a patient with subarachnoid hemorrhage. This case suggests that augmenting cardiac output may not be the only mechanism for the therapeutic benefit of milrinone.