Objectives: Analyses of incidence and time required to heal sternal wound infections after heart surgery performed via a median sternotomy between 2020 and 2022. Results: Superficial wound infections (SWI) were five times more common (2.7%) than mediastinitis (0.5%) among 2693 patients. The median time between the operation and diagnosis of SWI was 26 (interquartile range [IQR] 15-33) days vs. 16 (IQR 9-25) days for mediastinitis (p = .12). Gram-negative bacteria caused 44% of the 85 infections. Sternal wound infection correlated to higher body mass index, female sex, smoking, diabetes mellitus, previous myocardial infarction, coronary artery bypass grafting, use of internal mammary graft, and re-entry for postoperative bleeding. Eight of 59 patients (13.6%) with sternal wound infections had bilateral mammary grafts, compared to 102 of 1191 patients (8.6%) without wound infections (p = .28). Negative pressure wound therapy was always used to treat mediastinitis and applied in 63% of patients with SWI. Two of 13 patients with mediastinitis (15%) and none of 72 patients with SWI died within 90 days after the operation. The median time until the wound healed was 1.9 (IQR 1.3-3.7) months after SWI vs. 1.7 (IQR 1.3-5.3) months after mediastinitis (p = .63). Six patients (7%) required longer than one year to treat the infection. Conclusions: Postoperative sternal wound infections usually appeared several weeks after surgery and were associated with factors as high body mass index, diabetes mellitus and coronary artery bypass. SWI were more common than mediastinitis and often required negative pressure wound therapy and similar treatment time as mediastinitis.

To assess the impact of topical vancomycin (TV) application in decreasing sternal wound infections (SWIs) post cardiac surgery (CS), we lead a meta-analysis. Twenty-three thousand seven hundred and forty five participants had CS at the outset of the investigations, according to a thorough evaluation of the literature done up to November 2022; 8730 of them used TV, while 15 015 were controls. To assess the effectiveness of TV application in lowering SWIs following CS, odds ratios (OR) with 95% confidence intervals (CIs) were computed with dichotomous technique with a fixed- or random-effect model. The TV had significantly lower SWIs post CS (OR, 0.34; 95% CI, 0.20-0.57; P < .001), and deep SWIs post CS (OR, 0.26; 95% CI, 0.11-0.65; P = .004) compared with control as shown in Figures 2 and 3. Yet, there was no significant difference found amongst TV and control in superficial SWIs post CS (OR, 0.30; 95% CI, 0.07-1.30; P = .011). The TV had significantly lower SWIs, and deep SWIs post CS, and no significant difference was found in superficial SWIs post CS compared with control. The low number of included studies in this meta-analysis for superficial SWIs calls for precaution when analysing the outcomes.

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was is there a role for HbA1c in predicting morbidity and mortality outcomes after coronary artery bypass surgery? Eleven studies presented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The studies presented analyse the relationship between preoperative HbA1c levels and postoperative outcomes following coronary artery bypass graft (CABG) in diabetic, non-diabetic or mixed patient groups. Four studies found significant increases in early and late mortality at higher HbA1c levels, regardless of a preoperative diagnosis of diabetes. One study demonstrated that 30-day survival outcomes were significantly worse in patients with previously undiagnosed diabetes and elevated HbA1c compared with those with good control [HbA1c >6%; odds ratio 1.53, confidence interval (CI) (1.24-1.91); P = 0.0005]. However, four studies of early mortality outcomes in diabetic patients only showed no significant differences between patients with normal and those with deranged HbA1c levels (P = 0.99). There were mixed reports on morbidity outcomes. Three studies identified a significant increase in infectious complications in patients with poorly controlled HbA1c, two of which were irrespective of previous diabetic status [deep sternal wound infection (P = 0.014); superficial sternal wound infection (P = 0.007) and minor infections (P = 0.006) in poorly controlled diabetics only]. Four studies presented outcomes for total length of stay (LOS). Three of these papers looked specifically at diabetic patients, of which two found no significant differences in length of stay between good and poor preoperative glycaemic control [LOS: P = 0.59 and 0.86 vs P < 0.001]. However, elevated HbA1c vs normal HbA1c was associated with prolonged stay in hospital and in intensive care unit (ICU) in patients irrespective of previous diabetic status [total LOS (P < 0.001)]. Elevated HbA1c levels were also a significant predictor of reduced intraoperative insulin sensitivity in diabetic patients (R = -0.527; P < 0.001). Furthermore, higher HbA1c levels were associated with a reduced incidence of postoperative atrial fibrillation (P = 0.001). We conclude that elevated HbA1c is a strong predictor of mortality and morbidity irrespective of previous diabetic status. In particular, the mortality risk for CABG is quadrupled at HbA1c levels >8.6%. Some studies have called into question the predictive value of HbA1c on short-term outcomes in well-controlled diabetics; however, long-term outcomes in this population have not been reported.