Limb occlusion pressure-based individualized tourniquet pressure management in patients undergoing internal fixation...

This study aimed to evaluate the feasibility of limb occlusion pressure (LOP)-based individualized tourniquet pressure management and to quantify the reduction in applied tourniquet pressure compared with a traditional fixed-pressure protocol in patients undergoing internal fixation for extremity fractures.

A prospective comparative study was conducted at Civil Aviation Shanghai Hospital from January to September 2025. Patients undergoing internal fixation for extremity fractures were enrolled and allocated to either the LOP-based group (n = 171) or the traditional fixed-pressure group (n = 235) according to the attending surgical team and operative scheduling, without randomization. The LOP-based group received individualized tourniquet pressure based on preoperative LOP measurement plus a safety margin, while the control group received standardized pressures (40-50 kPa; 300-375 mmHg). The primary outcome was applied tourniquet inflation pressure. Secondary outcomes included demographic characteristics, extremity location, operative duration, and subgroup analyses stratified by extremity location, age, and sex; multivariable linear regression was performed to adjust for potential confounders.

The LOP-based group demonstrated significantly lower mean tourniquet pressure compared with the traditional group (32.82 +/- 3.63 kPa [246 +/- 27 mmHg] versus 48.21 +/- 3.84 kPa [362 +/- 29 mmHg]; mean difference: 15.39 kPa; 95% CI: 14.66-16.12; P < 0.001), representing a 31.93% reduction; the difference remained significant after adjustment for extremity location, age, and sex (adjusted mean difference: 15.71 kPa; 95% CI: 15.36-16.06; P < 0.001). Baseline characteristics including age (46.09 +/- 15.20 versus 47.51 +/- 15.66 years; P = 0.361), sex distribution (P = 0.809), extremity location (P = 0.457), and operative duration (82.80 +/- 46.64 versus 80.55 +/- 43.50 min; P = 0.618) were comparable between groups. Within the LOP-based group, applied pressure was lower for upper than for lower extremity procedures (26.24 +/- 4.21 versus 34.16 +/- 1.30 kPa; P < 0.001), while exploratory analyses revealed no significant pressure variations across sex (male: 32.97 +/- 3.52 kPa; female: 32.53 +/- 3.85 kPa; P = 0.445) or age categories (< 40, 40-59, >=60 years; P = 0.807). All procedures achieved adequate intraoperative hemostasis without pressure escalation.

LOP-based individualized tourniquet pressure management was feasible and achieved a substantial reduction in applied tourniquet pressure while maintaining adequate intraoperative surgical field visualization in extremity fracture internal fixation. Applied pressure varied with extremity location but was independent of patient age and sex. Because patient-centered clinical outcomes were not assessed, these findings demonstrate the feasibility and pressure-reducing effect of LOP-based protocols rather than proven clinical superiority; randomized trials with clinical endpoints are warranted.