Does dexamethasone induce myocardial injury after total knee arthroplasty?

Use of dexamethasone has no effect on postoperative concentration of cardiac troponin I (TnI) or T (TnT) on the first postoperative morning after total knee arthroplasty (TKA), suggests a recent study.

A subgroup analysis of the randomized DEX-2-TKA trial was conducted to assess the effect of dexamethasone versus placebo on the concentration of TnI and TnT on the first postoperative morning following TKA. The researchers also evaluated the frequency of myocardial injury after noncardiac surgery (MINS), myocardial infarction, and major adverse cardiovascular events.

A total of 290 patients who received either 24 mg of dexamethasone intravenously (administered perioperatively) or placebo were included in the analysis. Their blood samples were analysed as either TnI or TnT depending on the trial site.

Of the patients, 236 and 38 had eligible sample for analysis of TnI and TnT, respectively, on the first postoperative morning. The median TnI concentrations were 4.6 and 4.5 ng/L (p=0.96) in the dexamethasone and placebo groups, respectively, while the corresponding median TnT concentrations were 9 and 8 ng/L.

In addition, no significant differences were observed in the frequencies of MINS, myocardial infarction, and major adverse cardiovascular events between groups. However, these analyses were underpowered, according to the authors.

“We found no effect of dexamethasone on postoperative concentration of TnI or TnT on the first postoperative morning after TKA,” the authors said.

“MINS carries a high postoperative mortality,” they noted.