Journal List > Tuberc Respir Dis > v.68(3) > 1001483

Choi, Kim, Kim, Hong, Lim, Koh, Kim, and Lim: Associated Factor Related to Major Complications of Patients with Hospitalized for 2009 H1N1 Influenza Pneumonia

Abstract

Background

To date, there are few data on the risk factors for severe cases and deaths associated with the 2009 pandemic H1N1 influenza A. Here, we describe the clinical and epidemiologic characteristics of patients hospitalized for pneumonia and identify those factors associated with the development of major complications (MC).

Methods

We reviewed the medical records of 41 cases of pneumonia admitted to a university-affiliated tertiary hospital between Aug 26 and Dec 10, 2009, and who had confirmed H1N1 influenza A based on real-time reverse transcriptase-polymerase-chain-reaction assay. There were 7,962 patients that fit these criteria. We compared the clinical features and demographic characteristics of patients who developed MC to with those who did not develop MC.

Results

During the study period, 10 patients developed MC (required admission to the intensive care unit, n=10; required ventilator therapy, n=6; death, n=4). Patients with MC were significantly older than those without MC and more frequently had underlying medical conditions (90.0% vs 41.9%, p-value <0.01). In the patients with developed MC, the median PaO2/FiO2 ratio of 230.0 (145.0~347.3) at admission and pneumonia severity index (PSI) score of 141.5 (88.3~158.5) were higher than patients without MC. However, no differences were observed in laboratory findings or in viral shedding between the 2 groups.

Conclusion

In hospitalized pneumonia patients of 2009 H1N1 influenza, old age, a history of malignancy, initial hypoxemia, PaO2/FiO2 ratio, and PSI score appear to be risk factor significantly related to developing MC. These findings might be the basis to influence strategies for admitting patients to an intensive or intermediate care unit and for pre-emptive antiviral therapy.

Figures and Tables

Table 1
Baseline clinical characteristics of major complications (MC) group and non-MC group
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Values are expressed as median (inter-quartile range) or n (%).

MC: major complications; DM: diabetes mellitus; BMI: body mass index; SBP: systolic blood pressure; DBP: diastolic blood pressure; PaO2: partial oxygen tension in arterial blood; FiO2: fraction of inspired oxygen; PSI: pneumonia severity index.

Table 2
Baseline laboratory findings and outcomes of the study population
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Values are expressed as median (inter-quartile range) or n (%).

MC: major complications, WBC: White blood cell, BUN: blood urea nitrogen, CK: creatinine phosphokinase, LD: lactate dehydrogenase; BNP: B-natriuretic peptide, CRP: C-reactive protein, ABGA: arterial blood gas analysis, PaO2: partial oxygen tension in arterial blood.

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