[Intensive care patients with influenza A (H1N1) infection in Iceland 2009].

Background: We describe the main characteristics of patients that required intensive care due to the influenza (H1N1) outbreak in 2009.

Methods: Retrospective and prospective analysis of medical records from patients admitted to ICU with positive RT-PCR for (H1N1).

Results: During a six week period in the fall of 2009, 16 patients were admitted to intensive care in Iceland with confirmed H1N1 infection. Mean age was 48 years (range 1-81). Most patients were considered quite healthy but the majority had risk factors such as smoking, obesity or hypertension. All but one had fever, cough, dyspnea and bilateral infiltrates on chest x-ray and developed any organ failures (mean SOFA score 7). 12 needed mechanical ventilation and two extra corporeal membrane oxygenation (ECMO). Mean APACHE II score was 20. No patient died in the ICU but one elderly patient with multiple underlying diseases died a few days after being discharged from the ICU.

Conclusions: (1) The incidence of severe influenza A (H1N1) that leads to ICU admission appears to be high in Iceland. (2) Many patients developed acute respiratory distress syndrome in addition to other organ failures, and required additional measures for oxygenation such as prone position, nitric oxide inhalation and ECMO. (3) 28 day mortality was low. (4) This study will aid in future outbreak planning in Iceland. Key words: influenza A, pneumonia, multiple organ failure, death rate, intensive care, ventilator therapy, ECMO.