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Decompressive craniectomy for intracranial hypertension in vaccine-induced immune thrombotic thrombocytopaenia: a case series.

BACKGROUND
Vaccines have been key in preventing COVID-19 infections and the AstraZeneca (AZ) vaccine has been widely used. However, increased rates of thromboembolic events were identified in recipients and, subsequently, a syndrome of vaccine-induced immune thrombotic thrombocytopaenia (VITT) was described whereby recipients presented with venous sinus thromboses, haemorrhagic infarctions, and - consequently - raised intracranial pressure. National guidance recommended decompressive craniectomies for refractory intracranial hypertension. We describe our neurosurgical experience in managing a cohort of patients with VITT.


CLINICAL PRESENTATION
Four patients were included (three females and one male); median age was 46 years. All patients presented with a constellation of headache, focal neurological deficit(s), altered consciousness, and/or seizure at a median 11 d post-vaccine. Pre-operatively, median GCS was 7 and the median platelet count was 28 × 109/L. Mean craniectomy size was 13 cm × 10 cm. All four cases tested positive for anti-PF4 antibodies. Median length of stay was 9 d (range: 2-25). Of the four who were operated upon, two survived to hospital discharge, and one of these subsequently died at a peripheral hospital.


CONCLUSIONS
VITT-related sinus thromboses and associated infarcts are rare complications of the AZ vaccine. Neurosurgical management involves treating intracranial hypertension however survival outcomes in our cohort were poor. In our series, decompression was performed in deteriorating patients however prophylactic decompression, in the presence of extensive venous sinus thrombosis, should be considered on a case-by-case basis. As vaccination programmes accelerate across the world, neurosurgeons are likely to be increasingly involved in managing intracranial hypertension in patients with VITT-related sinus thromboses.