Complications in Pediatric Mechanical Circulatory Assistance: Evaluation of Infection Management.

Overview

End-stage heart failure in children is a rare cause of infant mortality. The most frequent cause is dilated cardiomyopathy, often of undetermined origin, which can lead to cardiogenic shock refractory to standard medical treatment. In such cases, it is essential to resort to exceptional means, available at tertiary care hospitals such as in Lyon. The therapeutic means includes long-term circulatory assistance (VAD). This type of circulatory assistance is becoming increasingly used in view of the shortage of heart transplants. Indeed, the average waiting time on the paediatric transplant list varies from 3 months to over a year for children under 5. Berlin Heart EXCOR (BHE) is the only long-term support available for children (2). It is a pulsatile para-corporeal assisting device with percutaneous cannulas. Despite technical and medical advances in circulatory support, the presence of foreign material is frequently complicated by infection. Infection is a major cause of morbidity and mortality in this population. It is most often of nosocomial origin, linked to central line infections. The germs associated with these infections are mainly bacteria, with a small proportion of fungi. The most common pathogens are multi-resistant gram-positive bacteria, which colonize the skin, adhere to the implanted equipment and create biofilms. Infections have a major impact on the morbidity and mortality of patients undergoing mechanical assistance, with an increased risk of thrombo-embolic events and difficulty in managing anticoagulation, secondary to inflammation.

There are few literatures on the management of infections under mechanical assistance. Current ISHLT (International Society for Heart and Lung Transplantation) recommendations are based on expert opinion and observational studies. Actual recommendations are long-term anti-infective therapy, even up to the time of transplantation in the case of assistance-specific or assistance-associated infections. At the Hospices Civils de Lyon, BH-assisted patients awaiting transplantation are cared for in the paediatric cardiac intensive care unit (PCICU). Infections are managed jointly with the infectious diseases team, through weekly consultations and RCP. The management strategy is directed towards the rational use of antibiotics and antifungals, to limit the impact of broad-spectrum, long-term antibiotic therapy on the microbiological environment and on the patient. The duration of anti-infective therapy is limited on the basis of clinical and biological criteria. In some cases, recurrence of the infectious episode may occur. This study will provide information on the therapeutic strategy for VAD infections.