A randomized comparative evaluation of local infiltration analgesia, extended nerve blocks, and conventional analgesia in pain management after total knee arthroplasty

Abstract

Objectives: The aim of this study was to analyze the postoperativeeffects of extended nerve blocks and local infiltration analgesia (LIA) onpostoperative pain control, muscle weakness, and blood loss after totalknee arthroplasty (TKA).Patients and methods: Between February 24th 2020 andJuly 10th 2020, a total of 161 patients (55 males, 106 females;median age: 69.0 years [IQR 63.0-75.0], range, 41 to 81 years) whounderwent primary TKA were randomly allocated into three parallelgroups according to their concomitant procedure in a double-blindfashion: (i) those to whom nerve blockade was performed aftercompetition of surgery under the duration of spinal anesthesia(n=50); (ii) those to whom LIA was performed during surgery (n=52),and (iii) control group (n=59). The content of LIA was 10-10 mL of20 mg lidocaine with 0.01 mg adrenalin and 100 mg ropivacaine,1 mL (30 mg) ketorolac, and 5 mL (500 mg) tranexamic acid wasdiluted by 50 mL 0.9% NaCl under aseptic conditions. Outcomeparameters were the evaluation of pain until the evening of firstpostoperative day (24 to 36 h), mobilization, and blood loss withinthe first three postoperative days.Results: The pain was maximal between 4 and 8 h postoperatively,when the effect of the spinal anesthetic drugs disappeared. During thiscritical period, tolerable pain (Numerical Rating Scale, NRS ≤3) wasobserved in 52%, 42%, and 19% of nerve blockade in LIA and controlgroups, respectively. None of the patients complained of high-intensitypain (NRS >8) in the LIA group, which was a significant differencefrom the block and control groups (10% and 14%, p