Brain stem haemorrhage during transsphenoidal surgery. Possible risk of the manoeuvre of increasing the endexpiratory pressure in a case of pituitary adenoma associated with dural arteriovenous malformation. Case report.

The authors report a case of pituitary adenoma associated with dural arteriovenous malformation (AVM), which caused brain stem haemorrhage during transsphenoidal surgery. The manoeuvre of increasing the endexpiratory pressure in order to push the suprasellar component of the adenoma down to the sella turcica could be the reason of this bleeding. The authors therefore recommend that in cases of such a combination any manoeuvres which are likely to increase the intracranial venous pressure or otherwise affect the intracranial pressure, are avoided. The dural AVM spontaneously regressed after haemorrhage.