Outcomes of initial conservative management in patients with acute subdural hematoma

<p>Although the surgical indication of acute subdural hematoma (ASDH) is described in guidelines, outcomes of initial conservative management have not been investigated in detail. The purpose of the present study was to clarify frequency and causes of neurological aggravation during initial conservative management for ASDH.</p><p>Patients with ASDH treated at the Akita University Hospital between April 2014 and September 2022 were reviewed retrospectively. Patients who received initial conservative management because of non–severe neurological deficits were divided into two groups; with or without fur­ther neurological aggravation. Risk factors, reasons of the aggrava­tion, treatment after the aggravation and clinical outcomes were analyzed.</p><p>In a total of 73 patients with ASDH, 58 (79.5%) patients were initially managed conservatively. Among 42 non–severe cases, 30 (71.4%) pa­tients had no further neurological aggravation. Twelve (28.6%) patients with neurological aggravation (between day 1 – 11) had significantly thicker initial ASDHs and lower Glasgow Coma Scales at discharge than those without aggravation. The causes of the aggravation included hematoma enlargement and seizure in 2 cases each, systemic complications in 1, and others in 7 cases. In the last 7 cases, hyperintensity lesions in the cerebral cortex adjacent to the hematoma on arterial spin labelling (ASL) images were observed in 6 cases and abnormal electro­encephalography (EEG) findings (spike–and–waves or slow waves) in 3 cases. In four of these 7 cases, hematoma removal was performed resulting in improving their clinical symptoms.</p><p>In conclusion, in patients with ASDH who were initially managed conservatively due to non–severe neurological deficits, further aggravation was observed in 12 (28.6%). Six (50.0%) of these showed ASL and/or EEG findings that may not contradict non–convulsive seizures. To clarify the causes of neurological aggravation during initial con­servative management more precisely, further investigation employing continuous EEG will be expected.</p>