Journal Article

Pandemic 2009 Influenza A in Argentina: A Study of 337 Patients on Mechanical Ventilation

Reina, Rosa, Valentini, Ricardo, Orlandi, Cristina, Brizuela, Matías, Mare, Sebastián, Balasini, Carina, Ilutovich, Santiago, Giuliani, Javiera, Estenssoro, Elisa, Neira, Jorge, Tiribelli, Norberto, Ríos, Fernando G., Apezteguía, Carlos, Valdez, Pascual, Gómez, Alejandro, Ceraso, Daniel H., Barrios, Cecilia, Domeniconi, Gustavo

2010

Overview

Abstract Rationale The rapid spread of the 2009 Influenza A (H1N1) around the world underscores the need for a better knowledge of epidemiology, clinical features, outcomes, and mortality predictors, especially in the most severe presentations. Objectives To describe these characteristics in patients with confirmed, probable, and suspected viral pneumonia caused by 2009 influenza A (H1N1) admitted to 35 intensive care units with acute respiratory failure requiring mechanical ventilation in Argentina, between June 3 and September 7. Methods Inception-cohort study including 337 consecutive adult patients. Data were collected in a form posted on the Argentinian Society of Intensive Care website. Measurements and Main Results Proportions of confirmed, probable, or suspected cases were 39%, 8%, and 53% and had similar outcomes. APACHE II was 18 ± 7; age 47 ± 17 years; 56% were male; and 64% had underlying conditions, with obesity (24%), chronic obstructive respiratory disease (18%), and immunosupression (15%) being the most common. Seven percent were pregnant. On admission, patients had severe hypoxemia (PaO2/FiO2 140 [87–200]), extensive lung radiologic infiltrates (2.87 ± 1.03 quadrants) and bacterial coinfection, (25%; mostly with Streptococcus pneumoniae). Use of adjuvants such as recruitment maneuvers (40%) and prone positioning (13%), and shock (72%) and acute kidney injury requiring hemodialysis (17%), were frequent. Mortality was 46%, and was similar across all ages. APACHE II, lowest PaO2/FiO2, shock, hemodialysis, prone positioning, and S. pneumoniae coinfection independently predicted death. Conclusions Patients with 2009 influenza A (H1N1) requiring mechanical ventilation were mostly middle-aged adults, often with comorbidities, and frequently developed severe acute respiratory distress syndrome and multiorgan failure requiring advanced organ support. Case fatality rate was accordingly high.

• Publisher: Oxford University Press,American Thoracic Society
• Subject: Adult / Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy / APACHE / Argentina - epidemiology / Biological and medical sciences / Body mass index / Chronic obstructive pulmonary disease / Cohort analysis / Cohort Studies / Disease Outbreaks / Emergency and intensive respiratory care / Fatalities / Female / Hemodialysis / Hospitals / Humans / Hypoxia - mortality / Illnesses / Influenza / Influenza A Virus, H1N1 Subtype / Influenza, Human - complications / Influenza, Human - mortality / Influenza, Human - therapy / Intensive care / Intensive care medicine / Kidneys / Laboratories / Male / Medical sciences / Middle Aged / Mortality / Pandemics / Patient positioning / Pneumonia / Pneumonia, Pneumococcal - complications / Pneumonia, Pneumococcal - mortality / Pregnancy / Respiration, Artificial / Respiratory distress syndrome / Respiratory Distress Syndrome, Adult - etiology / Respiratory Distress Syndrome, Adult - mortality / Respiratory Distress Syndrome, Adult - therapy / Respiratory failure / Streptococcus infections / Ventilators / Viruses