Low Tidal Volume Ventilation Is Associated with Reduced Mortality in HIV Patients with Acute Lung Injury

Respiratory failure remains the main indication for intensive care unit (ICU) admission and is still a leading cause of death for HIV-infected individuals despite overall improvements in ICU mortality.

It is unclear whether these improvements are due to combination antiretroviral therapy, low tidal-volume ventilation for acute lung injury, or both.

The aims of the current study, published in the June 5, 2008 online edition of Thorax, were to:

• Identify therapies and clinical factors associated with mortality related to acute lung injury among HIV-infected patients with respiratory failure during the period 1996-2004.

• Compare mortality in 2002, before and after introduction of low tidal volume-ventilation, a method that supports adequate ventilation and oxygenation in people with acute lung injury, such as may occur due to Pneumocystis pneumonia or other serious lung conditions.

Researchers at the University of California in San Francisco performed a retrospective cohort study of 148 consecutive HIV-infected adults admitted to the ICU at San Francisco General Hospital with acute lung injury requiring mechanical ventilation.

The investigators abstracted demographic and clinical information from medical records, including data on mechanical ventilation, and performed multivariate analysis using logistic regression.

Results

• In-hospital mortality was similar before and after introduction of a low tidal-volume ventilation protocol, although the study was not powered to exclude a clinically significant difference (P = 0.51).

• Combination antiretroviral therapy was not clearly associated with mortality, except among patients with Pneumocystis pneumonia.

• Among patients with acute lung injury, lower tidal volume was associated with decreased mortality after controlling for Pneumocystis pneumonia, serum albumin, severity of illness, gas-exchange impairment, and plateau pressure (P = 0.043).

Based on these findings, the study authors concluded, "Lower tidal volume ventilation was independently associated with reduced mortality in HIV-infected patients with acute lung injury and respiratory failure."

University of California, San Francisco, CA.

6/17/08

Reference

JL Davis, A Morris, RH KAller, and others. Low Tidal Volume Ventilation Is Associated with Reduced Mortality in HIV-infected Patients with Acute Lung Injury. Thorax. June 5, 2008 [Epub ahead of print].

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