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

ABSTRACT

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.