Venous thromboembolism chemical prophylaxis after endoscopic trans-sphenoidal pituitary surgery.

Purpose: There is no compelling outcome data or clear guidance surrounding postoperative venous thromboembolism (VTE) prophylaxis using low molecular weight heparin (chemoprophylaxis) in patients undergoing pituitary surgery. Here we describe our experience of early chemoprophylaxis (post-operative day 1) following trans-sphenoidal pituitary surgery.

Methods: Single-centre review of a prospective surgical database and VTE records. Adults undergoing first time trans-sphenoidal pituitary surgery were included (2009-2018). VTE was defined as either deep vein thrombosis and/or pulmonary embolism within 3 months of surgery. Postoperative haematomas were those associated with a clinical deterioration together with radiological evidence.

Results: 651 Patients included with a median age of 55 years (range 16-86 years). Most (99%) patients underwent trans-sphenoidal surgery using a standard endoscopic single nostril or bi-nostril trans-sphenoidal technique. More than three quarters had pituitary adenomas (n = 520, 80%). Postoperative chemoprophylaxis to prevent VTE was administered in 478 patients (73%). Chemoprophylaxis was initiated at a median of 1 day post-procedure (range 1-5 days postoperatively; 92% on postoperative day 1). Tinzaparin was used in 465/478 patients (97%) and enoxaparin was used in 14/478 (3%). There were no cases of VTE, even in 78 ACTH-dependent Cushing's disease patients. Six patients (1%) developed postoperative haematomas. Chemoprophylaxis was not associated with a significantly higher rate of postoperative haematoma formation (Fisher's Exact, p = 0.99) or epistaxis (Fisher's Exact, p > 0.99).

Conclusions: Chemoprophylaxis after trans-sphenoidal pituitary surgery on post-operative day 1 is a safe strategy to reduce the risk of VTE without significantly increasing the risk of postoperative bleeding events.