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

Minimal important difference in postoperative morphine consumption after hip and knee arthroplasty using nausea, vomiting, sedation and dizziness as anchors

BACKGROUND

Morphine-sparing effects are often used to evaluate non-opioid analgesic interventions. The exact effect that would warrant the implementation of these interventions in clinical practice (a minimally important difference) remains unclear. We aimed to determine this with anchor-based methods.

METHODS

This was a post hoc analysis of three studies investigating pain management after hip or knee arthroplasty (PANSAID [NCT02571361], DEX-2-TKA [NCT03506789] and Pain Map [NCT02340052]). The overall population was median aged 70, median ASA 2, 54% female. We examined the correlation between 0 and 24 h postoperative iv morphine equivalent consumption and the severity of nausea, vomiting, sedation and dizziness. The anchor was different severity degrees of these opioid-related adverse events. The primary outcome was the difference in morphine consumption between patients experiencing no versus only mild events. Secondary outcomes included the difference in morphine consumption between patients with mild versus moderate and moderate versus severe events. We used Hodges-Lehmann median differences, exact Wilcoxon-Mann-Whitney tests and quantile regression.

RESULTS

The difference in iv morphine consumption was 6 mg (95% confidence interval: 4-8) between patients with no versus only mild events, 5 mg (2-8) between patients with mild versus moderate events and 0 mg (-4 to 4) between patients with moderate versus severe events.

CONCLUSIONS

In populations comparable to this post-hoc analysis (orthopaedic surgery, median age 70 and ASA 2), we suggest a minimally important difference of 5 mg for 0-24 h postoperative iv morphine consumption.

Better Before-Better After: A Qualitative Phenomenology Study of Older Adults' Experiences With Prehabilitation Before Total Hip Replacement

Total hip replacement is considered a successful intervention for pain relief and improved function. However, poor presurgery physical function may increase the likelihood of delayed postsurgery recovery. The purpose of this study was to describe community-dwelling older adults' experiences with a prehabilitation program (preoperative exercise) before total hip replacement. Four participants were interviewed 13 and 15 weeks postsurgery. The interviews were recorded, transcribed, and analyzed with systematic text condensation. Physical, mental, and social limitations were, to a higher or lesser degree, part of the participants' life presurgery. The results indicate that tailored close supervised training presurgery increased the participants' amount of and adherence to exercise, confidence, and sense of control. The participants had a positive experience of increased strength during the training period and gained motivation to perform progressive training. The exercise program helped the participants be physically and mentally prepared. The results indicate that close supervised prehabilitation in community-dwelling older adults undergoing total hip replacement can contribute to improved function and increase the level of activity and self-efficacy postsurgery.

Minimal important difference in opioid consumption based on adverse event reduction-A study protocol

BACKGROUND

The patient-relevant minimal important difference for opioid consumption remains undetermined, despite its frequent use as primary outcome in trials on postoperative pain management. A minimal important difference is necessary to evaluate whether significant trial results are clinically relevant. Further, it can be used as effect size to ensure that trials are powered to find clinically relevant effects. By exploring the dose-response relationship between postoperative opioid consumption and opioid-related adverse effects, we aim to approximate the minimal important difference in opioid consumption anchored to opioid-related adverse effects.

METHODS

This is a post-hoc analysis of aggregated data from two clinical trials (PANSAID NCT02571361 and DEX2TKA NCT03506789) and one observational cohort study (Pain Map NCT02340052) on pain management after total hip and knee arthroplasty. The primary outcome is the Hodges-Lehmann median difference in opioid consumption between patients with no opioid-related adverse effects and patients experiencing the mildest degree of one or more opioid-related adverse effects (i.e., mild nausea, sedation and/or dizziness or vomiting). Secondary outcomes include the Hodges-Lehmann median difference in opioid consumption that corresponds to one point on a cumulated opioid-related adverse event 0-10 scale. Further, we will explore the proportion of patients that experience opioid-related adverse effects for consecutive opioid dose intervals of 2 mg iv morphine equivalents. Quantile regression will be used to assess any significant interactions with patient baseline characteristics.

CONCLUSIONS

This study will hopefully bring us one step closer to determining relevant opioid reductions and thereby improve our understanding of intervention effects and planning of future trials.

Drug-related challenges following primary total hip and knee arthroplasty

We aimed to characterize the in-hospital analgesic use among total hip or knee arthroplasty (THA or TKA) patients, and to identify possible drug-related challenges. We identified 15 263 patients operated with a THA or TKA between 1 January 2012 and 30 April 2016. The prevalence of analgesic users and patients with potential clinically relevant drug-drug interactions (DDIs), along with the prevalence of readmission among patients with vs. without a DDI, were calculated. A DDI was defined as the combination of (A) a diuretic, an angiotensin-converting enzyme inhibitor or an angiotensin II receptor blocker, and an non-steroidal anti-inflammatory Drug (NSAID); (B) warfarin and an NSAID; and (C) a benzodiazepine or a benzodiazepine-related drug and an opioid. The prevalence of analgesics administered in THA and TKA patients was 99.3% and 99.1% for paracetamol and 93.8% and 98.8% for opioids, respectively. The prevalence of patients who received interaction A, B or C was 8.4%, 2.5% and 40.7%, respectively. Patients with vs. without a DDI had a higher prevalence of 30-day readmission. In conclusion, most THA and TKA patients were administered paracetamol or opioids. The prevalence of 30-day readmission was higher in patients with than in patients without a potential clinically relevant DDI.

PROSPECT guideline for total hip arthroplasty: a systematic review and procedure-specific postoperative pain management recommendations

The aim of this systematic review was to develop recommendations for the management of postoperative pain after primary elective total hip arthroplasty, updating the previous procedure-specific postoperative pain management (PROSPECT) guidelines published in 2005 and updated in July 2010. Randomised controlled trials and meta-analyses published between July 2010 and December 2019 assessing postoperative pain using analgesic, anaesthetic, surgical or other interventions were identified from MEDLINE, Embase and Cochrane databases. Five hundred and twenty studies were initially identified, of which 108 randomised trials and 21 meta-analyses met the inclusion criteria. Peri-operative interventions that improved postoperative pain include: paracetamol; cyclo-oxygenase-2-selective inhibitors; non-steroidal anti-inflammatory drugs; and intravenous dexamethasone. In addition, peripheral nerve blocks (femoral nerve block; lumbar plexus block; fascia iliaca block), single-shot local infiltration analgesia, intrathecal morphine and epidural analgesia also improved pain. Limited or inconsistent evidence was found for all other approaches evaluated. Surgical and anaesthetic techniques appear to have a minor impact on postoperative pain, and thus their choice should be based on criteria other than pain. In summary, the analgesic regimen for total hip arthroplasty should include pre-operative or intra-operative paracetamol and cyclo-oxygenase-2-selective inhibitors or non-steroidal anti-inflammatory drugs, continued postoperatively with opioids used as rescue analgesics. In addition, intra-operative intravenous dexamethasone 8-10 mg is recommended. Regional analgesic techniques such as fascia iliaca block or local infiltration analgesia are recommended, especially if there are contra-indications to basic analgesics and/or in patients with high expected postoperative pain. Epidural analgesia, femoral nerve block, lumbar plexus block and gabapentinoid administration are not recommended as the adverse effects outweigh the benefits. Although intrathecal morphine 0.1 mg can be used, the PROSPECT group emphasises the risks and side-effects associated with its use and provides evidence that adequate analgesia may be achieved with basic analgesics and regional techniques without intrathecal morphine.

Using four different clinical tools as predictors for pain after total hip arthroplasty: a prospective cohort study

Background

Treatment of postoperative pain remains a significant clinical problem, and prediction of patients with a risk of higher postoperative pain levels is an important focus. We aimed to identify patients undergoing total hip arthroplasty (THA) with risk of higher pain levels at 24 h postoperatively by using four simple and easily available clinical tools.

Methods

This prospective observational cohort study included 102 patients having THA at Zealand University Hospital in Denmark. The following predictive tools were investigated for identifying patients with higher postoperative pain levels at 24 h postoperatively, both at rest and during mobilization: preoperative pain by peripheral venous cannulation (PVC) (dichotomized according to numerical rating scale pain ≤ 2/> 2 (PVC-Low/PVC-High) (primary outcome); the post anesthesia care unit (PACU) nurses’ expectations of patients pain levels; patients early pain levels at the PACU; and patients own forecast of postoperative pain levels. The Mann-Whitney U test was used to analyze comparisons between prediction groups. For the primary outcome we considered a p-value < 0.01 as statistically significant and for other outcomes a p-value of 0.05.

Results

We found no significant differences between the PVC groups for pain during mobilization at 24-h postoperatively: PVC-Low: 6 (4–8) (median, (IQR)) versus PVC-High: 7 (5–8) (median, (IQR)), p = 0.10; and for pain at rest: PVC-Low 2 (0–3) (median, (IQR)) versus PVC-High 3 (2–5) (median, (IQR)), p = 0.12. Other comparisons performed between predictive groups did not differ significantly.

Conclusions

In this prospective cohort study of 102 THA patients, we did not find that preoperative pain by PVC, when using a cut-off point of NRS ≤ 2, were able to predict postoperative pain at 24 h postoperatively. Neither did PACU nurses’ prediction of pain, patients forecast of pain, nor did maximum pain levels at the PACU.

Trial registration

Retrospectively registered 20th February 2018 at ClinicalTrials.gov (NCT03439566).