Examining the benefit of graduated compression stockings in the prevention of hospital-associated venous thromboembolism in low-risk surgical patients: a multicentre cluster randomised controlled trial (PETS trial).

INTRODUCTION: Hospital-acquired thrombosis (HAT) is defined as any venous thromboembolism (VTE)-related event during a hospital admission or occurring up to 90 days post discharge, and is associated with significant morbidity, mortality and healthcare-associated costs. Although surgery is an established risk factor for VTE, operations with a short hospital stay (<48 hours) and that permit early ambulation are associated with a low risk of VTE. Many patients undergoing short-stay surgical procedures and who are at low risk of VTE are treated with graduated compression stockings (GCS). However, evidence for the use of GCS in VTE prevention for this cohort is poor. METHODS AND ANALYSIS: A multicentre, cluster randomised controlled trial which aims to determine whether GCS are superior in comparison to no GCS in the prevention of VTE for surgical patients undergoing short-stay procedures assessed to be at low risk of VTE. A total of 50 sites (21 472 participants) will be randomised to either intervention (GCS) or control (no GCS). Adult participants (18-59 years) who undergo short-stay surgical procedures and are assessed as low risk of VTE will be included in the study. Participants will provide consent to be contacted for follow-up at 7-days and 90-days postsurgical procedure. The primary outcome is the rate of symptomatic VTE, that is, deep vein thrombosis or pulmonary embolism during admission or within 90 days. Secondary outcomes include healthcare costs and changes in quality of life. The main analysis will be according to the intention-to-treat principle and will compare the rates of VTE at 90 days, measured at an individual level, using hierarchical (multilevel) logistic regression. ETHICS AND DISSEMINATION: Ethical approval was granted by the Camden and Kings Cross Research Ethics Committee (22/LO/0390). Findings will be published in a peer-reviewed journal and presented at national and international conferences. TRIAL REGISTRATION NUMBER: ISRCTN13908683.

Traumatic dislocation of the pisiform: a case report.

Isolated pisiform dislocation is rare. We present one such case in a 20-year-old man occurring after a direct injury to the wrist. After an initial delay in diagnosis and unsuccessful closed reduction, he underwent resection of the pisiform. At 12-month follow-up, he had full range of movement of the wrist and no residual pain.

Venous thromboembolic disease after total hip and knee arthroplasty: current perspectives in a regulated environment.

Venous thromboembolic disease is the single most common reason for readmission to the hospital following total hip and total knee arthroplasty and remains a genuine threat to the life of the patient. Nevertheless, advances in surgical procedure, anesthetic management, and postoperative convalescence have altered the risks of venous thromboembolism after total joint arthroplasty in the lower extremity. Regional anesthetic techniques reduce the prevalence of venographic thrombosis by approximately 50%, and intraoperative monitoring has identified preparation of the femoral canal as the sentinel event that activates the coagulation cascade by the intravasation of marrow fat into the systemic circulation. Prevention of venographic thrombosis is most efficacious by administering fractionated heparin followed by warfarin; warfarin (international normalized ratio 2.0) appears to have a greater safety margin than fractionated heparin based on clinically meaningful bleeding events. Prevention of readmission events, proximal thrombosis, or pulmonary embolism has been demonstrated by using low-intensity warfarin. Aspirin, when used in conjunction with hypotensive epidural anesthesia after hip arthroplasty and regional anesthesia after knee arthroplasty, combined with pneumatic compression devices, also has been suggested to prevent clinical venous thromboembolism, as measured by readmission events. Oral thrombin inhibitors hold promise, but instances of liver toxicity have precluded approval in North America to date. Mechanical compression devices enhance venous flow and increase fibrinolytic activity in the lower extremity; clinical trials demonstrate efficacy in reducing venographic thrombosis alone after total knee arthroplasty and in combination with other chemoprophylactic agents after total hip arthroplasty. Extended chemoprophylaxis for 3 to 6 weeks after surgery is prudent in view of the protracted risk of thrombogenesis and the late occurrence of readmission for venous thrombosis and pulmonary embolism.

A novel approach to mechanical prophylaxis: calf impulse technology mimics natural ambulation more effectively than sequential calf compression.

BACKGROUND: The risk of thrombosis can be reduced by mechanical compression, but the optimal device is unknown. OBJECTIVES: To record the effect of natural ambulation on deep venous flow, providing a reference for evaluating the efficacy of mechanical compression systems, assuming that ambulation is the gold standard against which such systems should be compared; and to compare the hemodynamic effect of the A-V Impulse System CalfPad garment (A-VI) (Orthofix Vascular Novamedix, United Kingdom) with the SCD Express calf compression garment (SCD) (Covidien, USA). METHODS: Twelve healthy volunteers were recruited and randomly assigned to either A-VI or SCD in a two-device, two-period crossover design. Peak femoral velocity (PFV) was calculated using custom ultrasound software and compared with baseline values. Ultrasound images were recorded. RESULTS: A-VI augmented the mean (± SD) PFV to 59.79±29.07 cm/s compared with 22.86±5.73 cm/s for SCD. The actual percentage increase from baseline was approximately five times greater for A-VI (mean increase 385%±260%) than SCD (mean increase 81%±53%). Using an analysis of covariance model, with baseline fitted as a covariate, a highly statistically significant difference in favour of A-VI was detected (P=0.0002). Least square (adjusted) means (±95% CIs) were 37.24 cm/s (21.39 cm/s to 64.84 cm/s) for A-VI and 6.71 cm/s (3.86 cm/s to 11.69 cm/s) for SCD, representing more than fivefold greater improvement in PFV from rest with the A-VI device than with the SCD device. CONCLUSION: Pulsatile impulse calf compression (A-VI) more closely mimics PFV of normal ambulation than slow-squeeze sequential compression (SCD). Pulsatile calf compression may provide superior protection against thrombosis in immobile patients.

Venous impulse foot pumps: should graduated compression stockings be used?

It is not known whether the effect of Foot Pumps (Novamedix, Andover, UK) is enhanced by simultaneous use of graduated compression stockings (by controlling calf compliance) or hindered (by restricting preload). To address this question, we studied 20 healthy volunteers with duplex ultrasound. The peak velocity in the popliteal vein was measured at rest with the legs flat, foot-up, and foot-down, then it was measured when the AV Impulse Foot Pump was activated. These measurements each were performed with and without graduated compression stockings. In each leg position, the use of simultaneous graduated compression stockings reduced the peak velocity. On physiologic grounds, graduated stockings should not be used simultaneously with Foot Pumps.