The Effect of the IPACK Block on Pain After Primary TKA: A Double-Blinded, Prospective, Randomized Trial.

BACKGROUND: The purpose of this study was to determine if infiltration of local anesthetic between the interspace between the popliteal artery and capsule of the knee (IPACK) provides benefit in total knee arthroplasty. METHODS: Patients were randomized into continuous adductor canal block with IPACK block or continuous adductor canal block with sham subcutaneous saline injection. Only the anesthesiologist performing the block was aware of randomization status. After surgery, a blinded assessor recorded opioid consumption, pain scores, and gait distance. RESULTS: There were 35 patients in the IPACK group and 34 in the NO IPACK group. There was no difference demographically between the groups. In the postanesthesia care unit (PACU), the average (P = .0122) and worst (P = .0168) pain scores at rest were statistically lower in the IPACK group. There was no difference in the pain scores during physical therapy (P = .2080). There was no difference in opioid consumption in the PACU (P = .7928), or at 24 hours (P = .7456). There was no difference in pain scores on POD 1 in the AM (P = .4597) or PM (P = .6273), or in the walking distance (P = .5197). There was also no difference in length of stay in the PACU (P = .9426) or hospital (P = .2141). CONCLUSION: The IPACK group had lower pain scores at rest in the PACU, but this is likely not clinically significant. The routine use of the IPACK is not supported by the results of this study. There may be indications for the use of the IPACK block as a rescue block or in patients who have contraindications to our standard multimodal treatment regimen or in patients with chronic pain or opioid dependence.

Novel Regional Techniques for Total Knee Arthroplasty Promote Reduced Hospital Length of Stay: An Analysis of 106 Patients.

BACKGROUND: Novel regional techniques, including the adductor canal block (ACB) and the local anesthetic infiltration between the popliteal artery and capsule of the knee (IPACK) block, provide an alternative approach for controlling pain following total knee arthroplasty (TKA). This study compared 3 regional techniques (femoral nerve catheter [FNC] block alone, FNC block with IPACK, and ACB with IPACK) on pain scores, opioid consumption, performance during physical therapy, and hospital length of stay in patients undergoing TKA. METHODS: All patients had a continuous perineural infusion, either FNC block or ACB. Patients in the IPACK block groups also received a single injection 30-mL IPACK block of 0.25% ropivacaine. Pain scores and opioid consumption were recorded at postanesthesia care unit discharge and again at 8-hour intervals for 48 hours. Physical therapy performance was measured on postoperative days (POD) 1 and 2, and hospital length of stay was recorded. RESULTS: We found no significant differences in the 3 groups with regard to baseline patient demographics. Although we observed no differences in pain scores between the 3 groups, opioid consumption was significantly reduced in the FNC with IPACK group. Physical therapy performance was significantly better on POD 1 in the ACB with IPACK group compared to the other 2 groups. Hospital length of stay was significantly shorter in the ACB with IPACK group. CONCLUSION: This study demonstrated that an IPACK block reduced opioid consumption by providing effective supplemental analgesia following TKA compared to the FNC-only technique. ACB with IPACK provided equivalent analgesia and improved physical therapy performance, allowing earlier hospital discharge.

Ultrasound-guided popliteal sciatic nerve blockade in the severely and morbidly obese: a prospective and randomized study.

PURPOSE: Limited research data exist regarding optimal block techniques in the severely and morbidly obese patient population. We compared two approaches to sciatic nerve blockade at the popliteal fossa in severely and morbidly obese patients. The purpose of this study was to identify differences in pain scores, block onset characteristics, and adverse events between the proximal (prebifurcation) and the distal (postbifurcation) sites. METHODS: Patients with a body mass index ≥35 scheduled for unilateral foot surgery with a popliteal block were randomized to receive an ultrasound-guided popliteal block proximal or distal to the bifurcation of the sciatic nerve. The primary endpoint was numerical rating scale (NRS) scores in the post anesthesia care unit (PACU). RESULTS: Thirty patients were enrolled in each group for a total of 60 participants. Patients in the distal group had lower NRS scores upon entry into the PACU (0.70 ± 1.91) compared with the proximal group (2.17 ± 3.37), had a faster onset of sensorimotor blockade, and were less likely to require a repeat block procedure, conversion to general anesthesia, or local anesthetic supplementation by the surgical team. There was no difference in block procedure times or incidence of nerve injury between the two groups. CONCLUSIONS: The distal approach to the popliteal block provided several intraoperative and analgesic benefits without a difference in block procedural times in the severely and morbidly obese. It is a cost-free intervention that results in a higher likelihood of a successful block in a population where avoidance of opioids is desirable.

The adductor canal block provides effective analgesia similar to a femoral nerve block in patients undergoing total knee arthroplasty--a retrospective study.

STUDY OBJECTIVE: To determine the ability of an ultrasound-guided single-shot adductor canal block to provide adequate analgesia and improve performance during physical therapy. DESIGN: A retrospective chart review. SETTING: All procedures were performed at Ochsner Medical Center. MEASUREMENTS: Patient demographics as well as the type of peripheral nerve block performed. Pain scores and opioid consumption were recorded at postanesthesia care unit discharge and again at 8 ± 3, 16 ± 3, and 24 ± 3 hours. In addition, physical therapy performance was analyzed. MAIN RESULTS: There were no significant differences in pain scores or cumulative hydromorphone requirements between the adductor canal block group and the femoral nerve block group at any of the time points analyzed. Gait distance measured during physical therapy sessions in the adductor canal block group was superior compared with the femoral nerve block group. CONCLUSION: Within the first 24 hours, a single-shot adductor canal block provides equally effective analgesia when compared with a femoral nerve block and improves postoperative physical therapy performance.