Neue Influenza-A/H1N1-2009-Virus-Pandemie: Herausforderung für die Intensivmedizin

The novel pandemic influenza A/H1N1v has also led to a rapid increase in the number of new cases in Germany. In the majority of patients the disease has taken a mild clinical course. However, in isolated cases severe complications requiring hospitalization or intensive care treatment have occurred. Most of the current recommendations refer to outpatients or mild diseases and are not always suitable and practicable for the management of a life-threatening influenza A/H1N1v infection in an intensive care setting. The aim of this review is to present a reliable diagnostic and therapeutic approach for critically ill patients, considering the current literature, case-based experiences from our own intensive care unit and including relevant recommendations of public health authorities. Initial measures regarding therapeutic, diagnostic and isolation precautions arise from past medical history, current anamnesis and characteristic symptoms and their progression. Patients suspected of having acquired an influenza A/H1N1v infection should be isolated. Early laboratory diagnosis of A/H1N1v infection ideally utilizes the reverse transcriptase polymerase chain reaction (RT-PCR) as the most sensitive diagnostic method. Emerging evidence suggests that incidence and severity of life-threatening influenza A/H1N1v infection increase with several risk factors (e.g. pregnancy, immunosuppression, obesity). Treatment decisions should not be delayed to await laboratory confirmation in these patients as early initiation of antiviral therapy is recommended. Elements of supportive care depend on the presentation of complications and secondary organ failure. If rapidly progressive lung dysfunction occurs, refractory to routine mechanical ventilation, early reporting to centers experienced in the use of extracorporeal membrane oxygenation (ECMO) should be established.