A Case Of Acute Subdural Hematoma After Spinal Subarachnoid Anaesthesia For Surgery In The Perianal Region. A 22 yr female patient of ASA-Grade 1 was given spinal Subarachnoid anaesthesia with 0.5% Bupivacaine 2.5 ml at L3-4 space with 23 G needle . Analgesia upto T10 is obtained . fistulectomy operation was done . Intraoperative and postoperative haemodynamics were stable . 24 hrs later patient complained of mild headache which relieved with analgesics . But patient continued to have headache associated with vomiting ,sweating, and also became drowsy but arousable (GCS : E3V4M5 ).

left side sluggish reacting to light and dilated Right side normal size and reacting to light CT BRAIN showed Left frontotemporo parietal SDH which was managed conservatively for 15 days .But patient continued to have headache . Repeat CT brain revealed increased