Factors associated with death or intensive care unit admission due to pandemic 2009 influenza A (H1N1) infection

Abstract

Background : In preparation for pandemic HINI or H1N1 influenza (H1N1) it is necessary to identify factors associated with mortality of patients with HINI and hospital admissions to intensive care unit (ICU) of patients diagnosed in 2009 with HINI. Objectives : To describe the clinical and epidemiological features associated with 2009 HIN1 mortality and ICU patient admissions to Masih Daneshvari Teaching Hospital, Iran. Methods : A retrospective cross-sectional study was conducted among patients with mortality and admissions to ICU with confirmed HINI. Demographic, clinical, laboratory, radiological findings, and epidemiologic data were abstracted from medical records, using a standardized datasheet. Results : From June through December 2009, 20 out of the 46 confirmed hospitalized patients with confirmed H1NI were admitted to the ICU and 7 (15%) died. Among various variables, opium inhalation (P = 0.01), having productive cough, hemoptysis, chest pain, confusion, and loss of consciousness were significantly related to ICU admission (P < 0.05). Pleural effusion (P = 0.006), elevated liver enzymes, as well as CPK and LDH level were significantly relevant to ICU admission (P < 0.05). Delayed antiviral treatment was more common among patients who died and the elderly. Discussion : Patients who were admitted to ICU with confirmed H1N1 included the following risk factors: delayed initiation of antiviral therapy, history of opium inhalation and symptoms including; productive cough, hemoptysis, chest pain, confusion, and loss of consciousness. The mortality rate in the study population was high but compares favorably with other recent published studies.