[Complications of cardiac surgery: sternal dehiscence after median sternotomy. Analysis of 14,171 cases operated on in years 1990–2009].

Introduction: Dehiscence of the sternum is one of the most serious complications following cardiac surgery. It occurs after 0.2–5% of interventions with sternotomy access. The aim of the study was the evaluation of factors that may influence the frequency of this complication.

Material And Methods: A retrospective review of 14,171 patients undergoing median sternotomy for cardiac surgery between 1990 and 2009 at the Cardiac Surgery Department of the Pomeranian Medical University in Szczecin (Poland) was performed. The studied group consisted of 3,999 women (28.2%) and 10,172 men (71.8%) aged 11–87 years (59.8 years on average). We analysed cases with sternal dehiscence (SD), which occurred in 298 (2.1%) of the patients.

Results: The significant risk factors were: male sex (p = 0.0003), age (p < 0.00006), body mass (p < 0.00007), and use of both internal thoracic arteries (p < 0.00001). The risk of SD was also increased by coexisting diabetes and chronic obstructive lung disease (p < 0.012 and p < 0.02 respectively); however, discriminant analysis revealed that these variables were only linked to age. Apart from CABG, the type of surgical intervention had no influence on the frequency of SD. The total length of hospital stay in patients with SD was more than two times longer than in the rest of the patients (p < 0.00001). However, there were no significant differences in postoperative mortality between these two groups – 4.4% in the group with SD and 4.2% in the group without it.

Conclusions: Not being able to eliminate the influence of risk factors, since 2010 we decided to introduce changes in the method of sternum closure by increasing the number of wire loops from 6 to at least 8. For patients heavier than 80 kg, we assumed a ratio of one additional loop per every 10 kg of body mass, which should result in improved sternum stabilisation and reduce the risk of dehiscence.