Risk factors for median sternotomy dehiscence in cardiac surgery

We retrospectively reviewed several risk factors for median sternotomy dihiscence in our cardiac surgery patients for a recent 18-month period. We studied these factors by univariate and multivariate analysis with respect to sternal dehiscence. Univariate analysis showed several factors to be significant: female sex (P = .03), obesity (P = .002), diabetes (P = .01), and prolonged postoperative ventilation (P = .006). Mammary artery bypass versus saphenous vein bypass only approached significance (14% vs 3%, P = .11). Multivariate analysis showed obesity (P = .002), diabetes (P = .041), and prolonged postoperative ventilation (P = .005) to be important. We conclude that obese diabetic women are at extremely high risk for sternotomy dehiscence, and mammary artery bypass in this high-risk population may be a relative contraindication.