Schultz MJ, et al. - In this randomized clinical trial, researchers compared the effectiveness of a low tidal volume ventilation strategy vs an intermediate tidal volume strategy in critically ill patients in the intensive care unit (ICU) without acute respiratory distress syndrome (ARDS). Results showed that a low tidal volume strategy did not result in a greater number of ventilator-free days vs an intermediate tidal volume strategy in ICU patients without ARDS who were expected not to be extubated within 24 hours of randomization.

Methods

• This trial conducted from September 1, 2014, through August 20, 2017, and involved patients without ARDS expected to not be extubated within 24 hours after start of ventilation from six ICUs in the Netherlands.
• Main intervention analyzed was invasive ventilation using low tidal volumes (n=477) or intermediate tidal volumes (n=484).
• The number of ventilator-free days and alive at day 28 was the primary outcome.
• Length of ICU and hospital stay; ICU, hospital, and 28- and 90-day mortality; and development of ARDS, pneumonia, severe atelectasis, or pneumothorax were included secondary outcomes.

Results

• Participants included 961 patients (65% male), with a median age of 68 years (IQR: 59-76).
• A total of 475 patients in the low tidal volume group had a median of 21 ventilator-free days (IQR: 0-26), and 480 patients in the intermediate tidal volume group had a median of 21 ventilator-free days (IQR: 0-26) (mean difference, –0.27 [95% CI: –1.74 to 1.19] P=0.71) at day 28.
• No significant difference was found in ICU (median, 6 vs 6 days; 0.39 [–1.09 to 1.89] ; P=0.58) and hospital (median, 14 vs 15 days; –0.60 [–3.52 to 2.31]; P=0.68) length of stay or 28-day (34.9% vs 32.1%; HR: 1.12 [0.90 to 1.40]; P=0.30) and 90-day (39.1% vs 37.8%; HR: 1.07 [0.87 to 1.31]; P=0.54) mortality.
• No significant difference was found in the percentage of patients developing the following adverse events: ARDS (3.8% vs 5.0%; RR: 0.86 [0.59 to 1.24]; P=0.38), pneumonia (4.2% vs 3.7%; RR: 1.07 [0.78 to 1.47]; P=0.67), severe atelectasis (11.4% vs 11.2%; RR: 1.00 [0.81 to 1.23]; P=0.94), and pneumothorax (1.8% vs 1.3%; RR: 1.16 [0.73 to 1.84]; P=0.55).