Compression stockings unnecessary for inpatients who undergo elective surgery

Reference

Shalhoub J, Lawton R, Hudson J, et al, for the GAPS trial investigators. Graduated compression stockings as adjuvant to pharmaco-thromboprophylaxis in elective surgical patients (GAPS study): a randomised trial. BMJ 2020;369:m1309.

Synopsis

For surgical patients, the need for GCS as an adjunct to pharmacotherapy for thromboprophylaxis is unclear. In this UK study, investigators randomized adult inpatients who were undergoing elective surgery and had a moderate or high risk of VTE to receive either LMWH plus GCS (the current standard of care; n = 921) or LMWH alone (n = 937) throughout their hospital admission. The patients' risk of VTE was determined by the UK Department of Health risk assessment tool, as well as the Caprini risk assessment tool that takes into account factors such as age, significant comorbidities, and obesity. Pregnant women, patients with history of VTE, and those who required extended thromboprophylaxis beyond discharge were excluded. The 2 groups were similar at baseline: two-thirds were women, the mean age was 59 years, mean body mass index was 29, 84% had a high VTE risk, and 16% had a moderate VTE risk. The type of stockings used were mainly below-the-knee compression stockings. Approximately 60% of surgeries in both groups were classified as general upper gastrointestinal, obstetrics and gynecology, or general lower gastrointestinal, but no additional details were provided. The average length of hospital stay (and thus the duration of treatment) was also not provided. The full study intervention was delivered in 80% of patients in both groups. The primary outcome was new VTE within 90 days, either imaging-confirmed lower limb deep venous thrombosis with or without symptoms or pulmonary embolism with symptoms. The LMWH-alone group had a rate of VTE of 1.7% compared with 1.4% in the LMWH plus GCS group (risk difference 0.3%; 95% CI -0.65% to 1.26%). Since the 95% confidence interval did not cross the noninferiority margin of 3.5%, treatment with LMWH alone was shown to be noninferior to the other group. Results were similar in the per-protocol analysis and in subanalyses based on age (younger or older than 65 years) and baseline VTE risk (moderate or high).