Comparative analysis of pain in patients who underwent total knee replacement regarding the tourniquet pressure.

OBJECTIVES: To evaluate through the visual analog scale (VAS) the pain in patients undergoing total knee replacement (TKR) with different pressures of the pneumatic tourniquet.

METHODS: An observational, randomized, descriptive study on an analytical basis, with 60 patients who underwent TKR, divided into two groups, which were matched: a group where TKR was performed with tourniquet pressures of 350 mmHg (standard) and the other with systolic blood pressure plus 100 mmHg (P + 100). These patients had their pain assessed by VAS at 48 h, and at the 5th and 15th days after procedure. Secondarily, the following were also measured: range of motion (ROM), complications, and blood drainage volume in each group; the data were subjected to statistical analysis.

RESULTS: After data analysis, there was no statistical difference regarding the incidence of complications ( p  = 0.612), ROM ( p  = 0.202), bleeding after 24 and 48 h ( p  = 0.432 and p  = 0.254) or in relation to VAS. No correlation was observed between time of ischemia compared to VAS and bleeding.

CONCLUSIONS: The use of the pneumatic tourniquet pressure at 350 mmHg or systolic blood pressure plus 100 mmHg did not influence the pain, blood loss, ROM, and complications. Therefore the pressures at these levels are safe and do not change the surgery outcomes; the time of ischemia must be closely observed to avoid major complications.