Traitement des médiastinites post-sternotomie

Abstract

Mediastinitis occurs with an incidence of 1–2% in patients undergoing median sternotomy. Treatment requires prompt medical and surgical intervention. Pus evacuation and debridement of infected necrotic tissues are essential steps. The surgeon can either let the thorax open or use a closed technique. Open method requires daily dressings. Healing is obtained by granulation tissue formation but needs a long period of time. Thus, secondary closure is performed in the majority of cases. More often, mediastinal closure is performed using either continuous irrigation or vacuum drainage with Redon catheters or transposition of muscle or omental flaps. In our current practice, closed drainage using Redon catheters is the therapy of choice of acute mediastinitis because it is simple and efficient. It is only in case of closed drainage failure or in patients with extensive destruction and loss of tissue that transposition of muscle or omental flaps is used. Medical treatment is based on bactericidal systemic antibiotic therapy. Combine and prolonged antibiotic therapy is recommended, using drugs diffusing well in bone. Staphylococci are responsible for 70% of infections. Thus, antibiotics with antistaphylococcal spectrum should be considered in the absence of positive cultures. Shock, multiorgan failure or local complications can justify a prolonged ICU stay. Prognosis has improved over the last two decades but overall mortality is still approximately 20%. Several factors were found to be associated with bad outcome. Preventive measures are essential to reduce the risk of this nosocomial infection.