Does local infiltration analgesia reduce peri-operative inflammation following total hip arthroplasty? A randomized, double-blind study

Abstract Background Postoperative inflammation following total hip arthroplasty (THA) can lead to delayed mobilization and return of hip function. Our primary aim was to assess whether local infiltration analgesia (LIA) during surgery can prevent postoperative inflammation. Methods This is a sub-analysis of data from a broader double-blind study where 56 patients received spinal anaesthesia for THA. Additionally, Group FNB (Femoral Nerve Block) received an ultrasound-guided femoral nerve block using 30 mL of ropivacaine 7.5 mg/mL (225 mg), and 151.5 mL of saline peri-articularly intra-operatively. Group LIA received 30 mL saline in the femoral nerve block and ropivacaine 2 mg/mL, 300 mg (150 mL) + ketorolac 30 mg (1 mL) + adrenaline 0.5 mg (0.5 mL) peri-articularly. After 23 h, the LIA mixture (22 mL) was injected via a catheter placed peri-articularly in Group LIA and 22 mL saline in Group FNB. A battery of pro- and anti-inflammatory cytokines was assessed using a commercially available kit preoperatively and after 4 h and 3 days postoperatively. Additionally, CRP, platelet count and white blood count was determined pre- and postoperatively. Results There was a general trend towards an increase in pro-inflammatory cytokines postoperatively, which returned to normal levels after 3 days. IL-6 concentration was significantly lower 4 h postoperatively in Group LIA compared to Group FNB (p = 0.015). No other significant differences were found between the groups in other cytokines. CRP levels were significantly higher in Group FNB compared to Group LIA 3 days postoperatively (p < 0.001). No other significant differences were seen between the groups. Conclusion Local infiltration analgesia has a modest but short-lasting effect on postoperative inflammation in patients undergoing total hip arthroplasty. This is likely to be due to local infiltration of ketorolac and/or local anaesthetics in the LIA mixture. Future studies should be directed towards assessing whether the use of LIA translates into better patient outcomes. Trial registration EudraCT Number 2012-003875-20 . Registered 3 December 201

Pain management after total hip arthroplasty at five different Danish hospitals : A prospective, observational cohort study of 501 patients

BACKGROUND: The available literature does not present a "gold standard" for post-operative pain treatment after total hip arthroplasty (THA). The aim of this prospective observational study was to explore and document post-operative pain treatment, including outcomes, in a large cohort of patients undergoing THA at five different Danish hospitals.METHODS: This prospective, multicentre, observational cohort study of 501 THA patients was performed at five different hospitals in the Capital Region and at the Region Zealand in Denmark, from April 2014 to April 2016. The study had two co-primary outcomes: Pain during mobilisation at 6 hours post-operatively (numeric rating scale [NRS] [0-10]) and morphine consumption 0-24 hours post-operatively.RESULTS: A large variety of analgesic treatments were used at the included hospitals and none of the hospitals used the same non-opioid basic analgesic regimen. For all patients at all hospitals, the NRS-pain level during mobilisation at 6 hours was 5 (3-6), (median [interquartile range]) and the 24-hour intravenous morphine (eqv) consumption was 25 mg (18-35). Although some statistically significant differences between hospitals were found for morphine use, no non-opioid analgesic regimen demonstrated consistent clinically relevant superior efficacy. In general, pain levels at rest were low to moderate and pain during mobilisation was moderate.CONCLUSIONS: Analgesic treatment routines differed between hospitals. Pain levels, however, did not differ substantially and were in general low at rest and moderate during mobilisation. No non-opioid analgesic treatment demonstrated consistent analgesic superiority