DEX-2-TKA - DEXamethasone twice for pain treatment after Total Knee Arthroplasty: Detailed statistical analysis plan for a randomized, blinded, three-group multicentre clinical trial

Associations of dexamethasone's effect on morphine consumption after total knee arthroplasty-Subgroup analyses

The DEXamethasone twice for pain treatment after Total Knee Arthroplasty (DEX-2-TKA) trial showed that adding one and two doses of 24 mg intravenous dexamethasone to paracetamol, ibuprofen and local infiltration analgesia, reduced morphine consumption (primary outcome) within 48 h after TKA. We aimed to explore the differences in the effect of dexamethasone on morphine consumption in different subgroups. Quantile regression adjusted for site was used to test for significant interaction between the predefined dichotomised subgroups and treatment group. The subgroups were defined based on baseline data: sex (male/female), age (≤65 years/>65 years), American Society of Anaesthesiologists (ASA)-score (ASA I + II/III), visual analogue score of preoperative pain at rest (≤30 mm/>30 mm), pain during mobilisation (≤30 mm/>30 mm), type of anaesthesia (spinal anaesthesia/general anaesthesia and spinal converted to general anaesthesia), and prior daily use of analgesics (either paracetamol and/or NSAID/neither). These analyses were supplemented with post hoc multivariate linear regression analyses. Test of interaction comparing sex in the pairwise comparison between DX2 (dexamethasone [24 mg] + dexamethasone [24 mg]) versus placebo (p = .02), showed a larger effect of dexamethasone on morphine consumption in male patients compared to females. Test of interaction comparing age in the pairwise comparison between DX1 (dexamethasone [24 mg] + placebo) versus placebo (p = .04), showed a larger effect of dexamethasone on morphine consumption in younger patients (≤65 years) compared to older. All remaining subgroup analyses showed no evidence of a difference. The supplemental multivariate analyses did not support any significant interaction for sex (p = .256) or age (p = .730) but supported a significant interaction with the type of anaesthesia (p < .001). Our results from the quantile regression analyses indicate that the male sex and younger age (≤65 years) may be associated with a larger analgesic effect of dexamethasone than the effects in other types of patients. However, this is not supported by post-hoc multivariate linear regression analyses. The two types of analyses both supported a possible interaction with the type of anaesthesia.

Chronic Pain and Functional Outcome 3 years After Total Knee Arthroplasty and Perioperative Dexamethasone: A Follow-Up of the Randomized, Clinical DEX-2-TKA Trial

BACKGROUND

Perioperative dexamethasone as an adjunct to multimodal analgesia, has an opioid-sparing and pain alleviating effect after total knee arthroplasty (TKA), however, the 3-year effects are unknown. We aimed to investigate the 3-year effect of 1 (DX1) or 2 (DX2) intravenous doses of 24 mg dexamethasone or placebo on pain, physical function, and health-related quality of life after TKA.

METHODS

Patients who participated in the Dexamethasone Twice for Pain Treatment after TKA (DEX-2-TKA) were invited to physical tests and questionnaires (self-reported characteristics, Oxford Knee Score, EuroQol-5Dimensions-5Levels (EQ5D5L), and PainDetect). The tests were 40-meter Fast Paced Walk (40FPW) test, Timed Up and Go (TUG), 30 Second Chair Stand test (30CST), Stair Climb Test (SCT), bilateral knee Range of Motion, and knee extension torque. For each test the peak pain intensity was registered on a 0 to 100 mm Visual Analogue Scale. Primary outcome was average peak pain intensity during the 40FPW, TUG, 30CST and SCT. Secondary outcomes were the tests and questionnaires. Out of 252 eligible patients, 133 (52.8%) underwent the tests and 160 (63.5%) answered the questionnaires. Mean follow-up time was 33 months (range, 23 to 40).

RESULTS

Median (interquartile range) peak pain intensity was 0 (0 to 65) for the DX2 group, 0 (0 to 51) for DX1 group and 0 (0 to 70) for the placebo group (P = .72). No differences in secondary outcomes were identified.

CONCLUSION

One or 2 intravenous doses of 24 mg dexamethasone did not impact chronic pain development or physical function 3 years after TKA.

Effect of Dexamethasone on Myocardial Injury After Total Knee Arthroplasty: A Substudy of the Randomized Clinical DEX-2-TKA Trial

BACKGROUND

Myocardial injury after noncardiac surgery (MINS) carries a high postoperative mortality. In this preplanned, subgroup analysis of the randomized DEX-2-TKA Trial, we investigated the effect of dexamethasone versus placebo on the concentration of cardiac troponin I and T (TnI and TnT) on the first postoperative morning after total knee arthroplasty. In addition, frequency of MINS, myocardial infarction, and major adverse cardiovascular events where evaluated.

METHODS

We included 290 patients who received either 24 mg of dexamethasone intravenously (given perioperatively) or placebo. Blood samples were analyzed as either TnI or T depending on trial site.

RESULTS

A total of 236 samples were eligible for analysis of TnI and 38 samples for TnT on the first postoperative morning. The median (IQR) TnI concentration was 4.6 ng/L (0-7.2 ng/L) in the dexamethasone group and 4.5ng/l (0-7.0 ng/L) in the placebo group (P = .96) on the first postoperative morning. The median TnT was 9 ng/L (6-11 ng/L) in the dexamethasone group and 8 ng/L (5-10 ng/L) in the placebo group (P = .68). The frequencies of MINS, myocardial infarction, and major adverse cardiovascular events were similar in the compared groups, but these analyses were underpowered.

CONCLUSION

We found no effect of dexamethasone on postoperative concentration of troponin I or T on the first postoperative morning after total knee arthroplasty.

Risk of serious adverse events associated with non-steroidal anti-inflammatory drugs in orthopaedic surgery. A protocol for a systematic review

BACKGROUND

Postoperative pain is a common condition following orthopaedic surgeries and causes prolonged hospitalisation, delayed rehabilitation and hamper the quality of life. Non-steroidal anti-inflammatory drugs (NSAIDs) are effective analgesics and anti-inflammatory mediators in the treatment of postoperative pain. The association of NSAIDs with serious adverse events may however keep some clinicians and clinical decision makers from using NSAIDs perioperatively. The evidence regarding the risks of serious adverse events following perioperative use of NSAIDs in orthopaedic surgery is sparse and needs to be assessed in a systematic review. This is a protocol for a systematic review that aims to identify the risks of serious adverse events from perioperative use of NSAIDs in orthopaedic patients.

METHODS

Our methodology is based on the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols and the eight-step assessment procedure suggested by Jakobsen and colleagues. We wish to assess if NSAIDs versus placebo, usual care or no intervention, will influence the risks of serious adverse events in patients undergoing orthopaedic surgery. We will include all randomised trials assessing the use of NSAIDs perioperatively. To identify trials we will search the Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cochrane Central Register, Science Citation Index Expanded on Web of Science and BIOSIS. Two authors will screen the literature and extract data. We will use the 'Risk of Bias 2 tool' to assess trials. Extracted data will be analysed using RStudio and Trial Sequential Analysis. We will create a 'Summary of Findings' table in which we will present our primary and secondary outcomes. We will assess the quality of evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE).

DISCUSSION

This systematic review can potentially aid clinicians and clinical decision makers in the use of NSAIDs for treatment of postoperative pain following orthopaedic surgeries.

Effect of dexamethasone on intraoperative remifentanil dose in total knee arthroplasty surgery under general anaesthesia

Background

The effects of glucocorticoids may include both genomic and rapid nongenomic effects. The potential rapid analgesic effect during surgery has not previously been investigated. We aimed to explore the effect of dexamethasone on intraoperative infusion rate of remifentanil in patients undergoing total knee arthroplasty (TKA) surgery under general anaesthesia.

Methods

In this post hoc subgroup analysis, we included patients randomised in the DEX‐2‐TKA trial, who were operated under total intravenous anaesthesia with remifentanil and propofol. Trial medication, intravenous dexamethasone 24 mg or placebo, was administered immediately after anaesthesia onset. The primary outcome was the median weight‐corrected infusion rate of remifentanil during surgery. Secondary outcomes included median weight‐corrected infusion rate of propofol, median intraoperative bispectral index and time spent in the post‐anaesthesia care unit.

Results

Eighty‐seven patients were included in the analysis of the primary outcome. A significantly higher remifentanil infusion rate was observed in the dexamethasone group compared with the placebo group, p = .02. None of the secondary outcomes resulted in statistically significant differences between groups.

Conclusion

This explorative post hoc analysis of the randomised DEX‐2‐TKA trail showed that patients undergoing TKA surgery under general anaesthesia and who received dexamethasone seemed to have a higher remifentanil infusion rate compared with patients who received placebo. The clinical implications of the potentially increased remifentanil infusion rate need to be validated and explored further.

Clinical trial registration

ClinicalTrials.gov Identifier: NCT05002361 (12 August 2021).

Effect of dexamethasone as an analgesic adjuvant to multimodal pain treatment after total knee arthroplasty: randomised clinical trial

OBJECTIVE

To investigate the effects of one and two doses of intravenous dexamethasone in patients after total knee arthroplasty.

DESIGN

Randomised, blinded, placebo controlled trial with follow-up at 90 days.

SETTING

Five Danish hospitals, September 2018 to March 2020.

PARTICIPANTS

485 adult participants undergoing total knee arthroplasty.

INTERVENTION

A computer generated randomised sequence stratified for site was used to allocate participants to one of three groups: DX1 (dexamethasone (24 mg)+placebo); DX2 (dexamethasone (24 mg)+dexamethasone (24 mg)); or placebo (placebo+placebo). The intervention was given preoperatively and after 24 hours. Participants, investigators, and outcome assessors were blinded. All participants received paracetamol, ibuprofen, and local infiltration analgesia.

MAIN OUTCOME MEASURES

The primary outcome was total intravenous morphine consumption 0 to 48 hours postoperatively. Multiplicity adjusted threshold for statistical significance was P<0.017 and minimal important difference was 10 mg morphine. Secondary outcomes included postoperative pain.

RESULTS

485 participants were randomised: 161 to DX1, 162 to DX2, and 162 to placebo. Data from 472 participants (97.3%) were included in the primary outcome analysis. The median (interquartile range) morphine consumptions at 0-48 hours were: DX1 37.9 mg (20.7 to 56.7); DX2 35.0 mg (20.6 to 52.0); and placebo 43.0 mg (28.7 to 64.0). Hodges-Lehmann median differences between groups were: -2.7 mg (98.3% confidence interval -9.3 to 3.7), P=0.30 between DX1 and DX2; 7.8 mg (0.7 to 14.7), P=0.008 between DX1 and placebo; and 10.7 mg (4.0 to 17.3), P<0.001 between DX2 and placebo. Postoperative pain was reduced at 24 hours with one dose, and at 48 hours with two doses, of dexamethasone.

CONCLUSION

Two doses of dexamethasone reduced morphine consumption during 48 hours after total knee arthroplasty and reduced postoperative pain.

TRIAL REGISTRATION

Clinicaltrials.gov NCT03506789.