Popliteal Vein Compression Under General Anaesthesia

• Published in: European journal of vascular and endovascular surgery 2009-04, Vol.37 (4), p.464-469
• Main Authors: Huber, D.E, Huber, J.P
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Anesthesia, General - adverse effects; Body Mass Index; Constriction, Pathologic - etiology; Constriction, Pathologic - physiopathology; Deep vein thrombosis; Female; Heel elevator; Humans; Male; Middle Aged; Popliteal compression; Popliteal Vein - diagnostic imaging; Prospective Studies; Regression Analysis; Supine Position - physiology; Surgery; Ultrasonography, Doppler, Duplex; Young Adult
• ISSN: 1078-5884; 1532-2165
• DOI: 10.1016/j.ejvs.2008.11.015

Abstract Objectives To determine the incidence of popliteal vein compression in supine patients, who are under general anaesthesia and using heel elevators. Design A prospective cohort study. Methods The popliteal veins of 50 patients, lying supine under general anaesthesia, were insonated using duplex ultrasonography to determine the incidence of popliteal vein compression when the knees were flexed and extended. Result There was a statistically significant reduction in popliteal vein diameter in extension compared with the diameter in flexion (median diameter: flexed 7.6 mm, extended 2.1 mm, p < 0.001, Wilcoxon test). In extension, 43% of veins occluded, and a further 21% was compressed by ≥50%. There was a significant relationship to body mass index (BMI) but not to height, gender or age; all patients with BMI ≥30 displayed narrowing at least one vein by ≥50%. The relative risk of vein narrowing ≥50% or occlusion was 1.55 for BMI ≥25 versus