[Ultrasound and nerve stimulator guided continuous femoral nerve block analgesia after total knee arthroplasty: a multicenter randomized controlled study]

Peripheral Nerve Stimulator Versus Ultrasound-Guided Femoral Nerve Block for Knee Arthroscopy Procedures: A Randomized Controlled Trial

Background

Femoral nerve block (FNB) provides effective analgesia and is a widely used technique for postoperative pain relief for orthopedic procedures on lower limbs. This study aims to compare the efficacy of ultrasonography (USG) versus peripheral nerve stimulator (PNS)-guided FNB in knee arthroscopic procedures.

Methodology

This randomized comparative study included two study groups with 30 participants in each group who were given FNB with either PNS or USG for knee arthroscopic procedures following spinal anesthesia. The study evaluated the number of needle repositioning, the time taken for performing the block, the efficacy of postoperative analgesia based on the duration of the block, and patient satisfaction.

Results

The number of needle repositioning and time taken to finish the procedure using USG was lower compared to the group using PNS (p < 0.001). The duration of the block was comparable in both groups (p = 0.584). Patients were satisfied with both techniques and responded as either very good or outstanding and chose neither as inferior (p = 0.310).

Conclusions

Both techniques have equal efficacy concerning the duration of the effect of the block and patient satisfaction. However, the procedural time and number of needle repositioning were significantly less in the group where USG was used for the block.

Evaluation of analgesic regimens in total knee arthroplasty, retrospective study

OBJECTIVE:

Analgesic therapies have an immense role in early rehabilitation period after total knee arthroplasty (TKA) and multimodal approaches should be considered as the first choice of treatment. In this retrospective study, the aim was to evaluate the effectiveness of multimodal analgesic therapies for TKA, including femoral nerve block (FNB) and patient controlled analgesia (PCA).

METHODS:

The data of 79 patients who underwent TKA between January and December 2016 were retrospectively evaluated. In all, 63 patients met the inclusion criteria. Hemodynamic records and Visual Analogue Scale (VAS) pain scores for postoperative 0, 2, 4, 6, 9, and 12 hours were evaluated and patients were separated into 3 groups. Group 1: FNB with 0.25% bupivacaine, Group 2: FNB with 0.166% bupivacaine, and Group 3: No FNB.

RESULTS:

The average age of the patients was 64.3±14.9 years and average body mass index (BMI) was 32.5±5.3 kg/m². There was no statistical difference between groups in age, gender, American Society of Anesthesiologists (ASA) classification of physical health scores, BMI, or anesthesia type (p<0.05). When VAS scores at postoperative time intervals were compared, there was a statistically significant difference between Group 1 and Group 2 (p>0.05). When difference between Groups 1 and 3 and Groups 2 and 3 were compared, the difference was statistically significant for VAS 0 (p>0.05). Additional analgesic use was highest in Group 3.

CONCLUSION:

This study demonstrated that FNB significantly decreases postoperative pain intensity and additional analgesia requirement in patients undergoing TKA. A concentration of 0.166% bupivacaine is as effective as a concentration of 0.25% when used as part of a multimodal analgesia regimen in TKA.