High Positive End-Expiratory Pressure Is Associated with Improved Survival in Obese Patients with Acute Respiratory Distress Syndrome.

Abstract

BACKGROUND:

In acute respiratory distress syndrome, minimizing lung injury from repeated collapse and reopening of alveoli by applying a high positive end-expiratory pressure improves oxygenation without influencing mortality. Obesity causes alveolar atelectasis, thus suggesting that a higher positive end-expiratory pressure might be more protective among the obese. We hypothesized that the effect of applying a high positive end-expiratory pressure on mortality from acute respiratory distress syndrome would differ by obesity status.

METHODS:

This was a retrospective analysis of 505 patients from the Assessment of Low tidal Volume and elevated End-expiratory volume to Obviate Lung Injury Trial, a multicenter randomized trial that compared a higher vs a lower positive end-expiratory pressure ventilatory strategy in acute respiratory distress syndrome. We examined the relationship between positive end-expiratory pressure strategy and 60-day mortality stratified by obesity status.

RESULTS:

Among obese patients with acute respiratory distress syndrome, those assigned to a high positive end-expiratory pressure strategy experienced lower mortality compared with those assigned to a low strategy (18% vs 32%; P = .04). Among the nonobese, those assigned to high positive end-expiratory pressure strategy experienced similar mortality with those assigned to low strategy (34% vs 23%; P = .13). Multivariate analysis demonstrated an interaction between obesity status and the effect of positive end-expiratory pressure strategy on mortality (P <.01).

CONCLUSIONS:

Ventilation with higher levels of positive end-expiratory pressure was associated with improved survival among the subgroup of patients with acute respiratory distress syndrome who are obese.

• Authors: Christian Bime, Mallorie Fiero, Zhenqiang Lu, Eyal Oren, Cristine E Berry, Sairam Parthasarathy, Joe G N Garcia
• Journal: The American journal of medicine (Am J Med) Vol. 130 Issue 2 Pg. 207-213 (Feb 2017) ISSN: 1555-7162 [Electronic] United States
• PMID: 27984004 (Publication Type: Journal Article, Multicenter Study, Randomized Controlled Trial)
• Copyright: Copyright © 2016 Elsevier Inc. All rights reserved.

Topics

• Female
• Humans
• Male
• Middle Aged
• Obesity (complications, mortality)
• Positive-Pressure Respiration (methods)
• Respiratory Distress Syndrome (complications, mortality, physiopathology, therapy)
• Retrospective Studies
• Tidal Volume