Infectious Complications after Therapeutic Hypothermia for Cardiac Arrest

Abstract

Post-cardiac arrest shock and post-anoxic encephalopathy are the main determinants of the outcome after cardiac arrest. However, patients are also exposed to infectious complications, which affect a large proportion of survivors and represent supplementary insults. Diagnosis of infections is complicated after cardiac arrest, not only by the physiological effects of therapeutic hypothermia, which itself promotes bacterial infection by anti-inflammatory mechanisms, but also by the consequences of post-cardiac arrest syndrome. Studies are often impaired by retrospective design and lack of consensus on infections criteria in this setting. However, pneumonia and bloodstream infections are the most frequent infections, occurring in more than half of the survivors. Data converge on a lack of impact on survival or neurological outcome, but increased duration of mechanical ventilation or length of hospital stay is almost constant. Our article summarizes the epidemiology of infectious complications occurring after cardiac arrest, by examining pathophysiology, with special focus on therapeutic hypothermia. Prevention and antimicrobial therapy strategies are then reviewed. Notably, the possibility of antibiotic prophylaxis in patients after cardiac arrest is discussed. Throughout the article, we also expose and propose our practices of management of infectious complications after cardiac arrest.