Dataset Information

Elevated Driving Pressure and Elastance Does Not Increase In-Hospital Mortality Among Obese and Severely Obese Patients With Ventilator Dependent Respiratory Failure

ABSTRACT: Supplemental Digital Content is available in the text. Importance: Existing recommendations for mechanical ventilation are based on studies that under-sampled or excluded obese and severely obese individuals.

Objective:

To determine if driving pressure (DP) and total respiratory system elastance (Ers) differ among normal/overweight (body mass index [BMI] < 30 kg/m2), obese, and severely obese ventilator-dependent respiratory failure (VDRF) patients and if there any associations with clinical outcomes.

Design, Setting, and Participants:

Retrospective observational cohort study during 2016–2018 at two tertiary care academic medical centers using electronic health record data from the first 2 full days of mechanical ventilation. The cohort was stratified by BMI classes to measure median DP, time-weighted mean tidal volume, plateau pressure, and Ers for each BMI class.

Setting and Participants:

Mechanically ventilated patients in medical and surgical ICUs.

Main Outcomes and Measures:

Primary outcome and effect measures included relative risk of in-hospital mortality, ventilator-free days, ICU length of stay, and hospital length of stay with multivariable adjustment.

Results:

The cohort included 3,204 patients with 976 (30.4%) and 382 (11.9%) obese and severely obese patients, respectively. Severe obesity was associated with a DP greater than or equal to 15 cm H2O (relative risk [RR], 1.51 [95% CI, 1.26–1.82]) and Ers greater than or equal to 2 cm H2O/(mL/kg) (RR, 1.31 [95% CI, 1.14–1.49]). Despite elevated DP and Ers, there were no differences in in-hospital mortality, ventilator-free days, or ICU length of stay among all three groups.

Conclusions and Relevance:

Despite higher DP and ERS among obese and severely obese VDRF patients, there were no differences in in-hospital mortality or duration of mechanical ventilation, suggesting that DP has less prognostic value in obese and severely obese VDRF patients.

SUBMITTER: Terry C

PROVIDER: S-EPMC9750660 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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