Optimizing tourniquet pressures in knee arthroscopy: an international survey on current practice and a double-blind randomized trial.

BACKGROUND & PURPOSE: Pneumatic tourniquets improve surgical visualization during knee arthroscopy, but fixed high pressures may increase postoperative pain. This study investigated whether a minimal effective individualized occlusion pressure (MEIOP), calculated as limb occlusion pressure plus a safety margin, maintains surgical field quality while reducing pain compared to a standardized occlusion pressure (SOP).

METHODS

A preliminary survey of 79 orthopaedic surgeons identified 350 mmHg as the routine SOP. In a subsequent double-blind randomized clinical trial, patients undergoing elective knee arthroscopy were assigned to SOP (350 mmHg) or MEIOP, defined as Doppler-derived limb occlusion pressure plus a safety margin (mean ≈ 230 mmHg). Outcomes included surgical field quality, postoperative using a visual analog scale (VAS) up to 15 days, overall 15-day pain perception, and analgesic consumption.

RESULTS

Both groups achieved 100% excellent surgical field ratings. Pain trajectories differed significantly between groups over time (group × time interaction, p = 0.022). The MEIOP group experienced significantly lower pain at discharge (~ 6 h; p = 0.013, d = 1.14) and lower overall 15-day pain perception (p = 0.043, d = 0.89). Analgesic consumption showed a consistent descriptive trend favoring MEIOP throughout follow-up.

CONCLUSION

This proof-of-concept study suggests that individualizing tourniquet pressure using predefined MEIOP protocol preserves satisfactory surgical visualization and is associate with lower postoperative pain compared with a standard high-pressure protocol. This trial was prospectively registered at the Brazilian Clinical Trials Registry (ReBEC; RBR-4xd6cxm).