Lung Protective Ventilation during Pregnancy: An Observational Cohort Study

Area of Science:

• Critical Care Medicine
• Obstetrics and Gynecology
• Respiratory Medicine

Background:

• Mechanical ventilation in pregnant patients presents unique challenges due to physiological changes during gestation.
• Understanding ventilation strategies and outcomes is crucial for optimizing care in this vulnerable population.
• Previous research has not fully elucidated the characteristics and outcomes associated with different tidal volume strategies in pregnant women.

Purpose of the Study:

• To characterize mechanically ventilated pregnant patients.
• To evaluate the utilization of low-tidal-volume ventilation (LTVV) versus high-tidal-volume ventilation (HTVV) across pregnancy trimesters.
• To describe maternal and fetal outcomes associated with each ventilation strategy.

Main Methods:

• Retrospective cohort study of pregnant women requiring mechanical ventilation for over 24 hours (July 2012 - August 2020).
• Defined LTVV as average daily tidal volume ≤ 8 mL/kg of predicted body weight; HTVV as > 8 mL/kg.
• Analyzed demographic, maternal, fetal characteristics, and outcomes stratified by ventilation strategy.

Main Results:

• 52 pregnant women were identified; 43 received LTVV and 9 received HTVV.
• Acute respiratory distress syndrome (ARDS) affected 73% of patients; infection was a common indication for ventilation (63%).
• High rates of obstetric complications (21% preeclampsia/eclampsia), preterm delivery (60%), and fetal demise (16%) were observed.

Conclusions:

• LTVV was the predominant ventilation strategy used in pregnant patients across all trimesters.
• The study highlights a significant burden of maternal and fetal morbidity and mortality in this cohort.
• Infection is a frequent reason for mechanical ventilation during pregnancy, and prone positioning is feasible in advanced gestations.