DVT/PE Rates and Etiologies after Endoscopic/Endoscopic-Assisted Skull Base Surgery

Introduction: Endonasal/endoscopic-assisted (endo-assisted) skull base surgery is associated with protracted operative times, often followed by prolonged periods without ambulation, possibly increasing the risks of postoperative deep vein thrombosis (DVT) and pulmonary embolism (PE). However, perioperative DVT/PE prophylaxis is rarely administered for these procedures due to concern for intracranial hemorrhage. We therefore sought to establish the first evidence regarding incidence of DVT/PE after endoscopic/endo-assisted skull base surgery, and define any predisposing factors for DVT/PE following endoscopic skull base procedures.

Methods: Single institution, retrospective review of all endoscopic/endo-assisted skull base surgeries in patients >15 years old, over a 10-year period from 2009 to 2019, was conducted. Patient demographics, DVT/PE incidence and risk factors, hospital course, comorbidities, and Caprini’s score were enumerated. Skull base tumor properties including malignancy, functional adenomas, were also assessed. Revision surgeries performed in the same patient were each counted as separate events.

Results: A total of 1,122 patients met inclusion criteria. Overall incidence of DVT and/or PE in endoscopic/endo-assisted skull base surgery was 2.32% (26/1,122), including 1.6% (18/1,122) who experienced DVT only, and 1.25% (14/1,122) who had DVT with PE. With malignancies excluded, the absolute rate of DVT/PE for associated with endonasal skull base procedures was 1.9% (18/966). The overall mean, median and most frequent postoperative durations prior to DVT/PE occurrence were 5, 4.5, and 2 days respectively for the entire patient cohort, and 9, 6, and 4 days when malignant pathologies are excluded. For all patients, an increased risk of DVT and/or PE was associated with (1) decreased mobility (p < 0.000001); (2) recent pneumonia (p < 0.00001); (3) extended lumbar drain use (p < 0.0001); (4) recent stroke (p < 0.00018); (5) recent prior DVT/PE (p = 0.011); (6) malignant skull base tumor (p = 0.016); (7) varicose vein presence (p = 0.022); (8) hypertension (p = 0.024; (9) recent prior major surgery (p = 0.033; (10) hyperlipidemia (0.034); and (11) male gender (p = 0.037). Several preoperative endocrinopathies were also independent risk factors for postoperative development of DVT/PE: SIADH (p = 0.014), adrenal insufficiency (p = 0.002), hypothyroidism (p = 0.005), and Cushing’s syndrome (p = 0.013). For every 10 hours of inpatient admission, postoperative risk of DVT/PE incrementally increased (OR = 1.03, p = 0.003). Prolonged duration of hospitalization over 5 days from any condition also significantly augmented the risk of DVT/PE (OR = 4.47, p = 0.008). Finally, a mild elevation in the Caprini score (5.92 vs. 4.39) also increased the risk of DVT/PE (OR = 1.39, p = 0.003) following endoscopic/endo-assisted skull base surgery.

Conclusion: The incidence of DVT/PE following endoscopic/endo-assisted skull base surgery is approximately 2% (1.9–2.3%), with numerous associated risk factors also identified. A low-to-moderate Caprini’s score is still associated with increased DVT/PE risk after these advanced endonasal procedures. These data provide evidence to assist treatment teams in the design of DVT/PE prophylaxis guidelines for endoscopic/endo-assisted skull base surgery, and suggest that post-operative DVT/PE prophylaxis be considered following completion of postoperative days 3 and 4 in patients with preoperative risk factors or who require prolonged inpatient admission where appropriate.

No conflict of interest has been declared by the author(s).