Efficacy of Noninvasive Ventilatory Therapies Through Different Interfaces in the Postoperative Care of Cardiac Surgery Patients: A Randomized Controlled Trial.

Abstract

Objectives: To compare the clinical efficacy of 5 noninvasive ventilatory strategies-delivered via a conventional oronasal mask, a conventional full-face mask, the Wolf Mask full-face interface, the ELMO helmet (continuous positive airway pressure), and high-flow nasal cannula-against conventional physiotherapy without active ventilatory support in patients following elective cardiac surgery.

Design: Prospective, randomized, controlled trial.

Setting: High-complexity intensive care unit (ICU) of a tertiary care hospital from July 2023 to May 2026.

Participants: In total, 172 patients undergoing elective coronary artery bypass grafting or valve surgery, randomized into 6 groups (G-FA, G-FULL, G-WOLF, G-ELMO, G-TAF, and G-CONTR).

Interventions: Three daily 60-minute sessions of the assigned ventilatory modality integrated into standard physiotherapy care, from ICU admission to discharge.

Measurements and main results: The primary outcomes were interface comfort and mobilization progression, with postoperative pulmonary complications as a secondary outcome. The Wolf Mask achieved the highest comfort score (9.41 ± 0.68 on a 0-10 visual analog scale) and required the lowest inspiratory pressure support (5.62 ± 2.08 cmH₂O) to reach the target tidal volume (6 mL/kg ideal body weight), suggesting superior mechanical efficiency. It was the only interface with no recorded cases of bibasal atelectasis and showed the lowest overall pulmonary complication rate. The conventional full-face mask yielded the second-best performance in comfort, arterial oxygenation, and pulmonary protection. High-flow nasal cannula proved safe but offered no advantage over full-face interfaces in pulmonary or functional outcomes. The ELMO helmet was hemodynamically safe and produced no hypercapnia but registered comfort scores among the lowest, statistically comparable to those of the conventional oronasal mask, along with the poorest oxygenation values. The control group had the highest complication rate, the lowest mobilization levels, and the smallest proportion of patients reaching mobilization level 3 at ICU discharge (18% v 73%-74% in the full-face groups). Interface comfort was identified as an independent positive predictor of mobilization progression by linear mixed-effects modeling (p = 0.004).

Conclusions: In this trial, full-face interfaces, and the Wolf Mask in particular, were associated with the highest comfort and the lowest inspiratory pressure support, and interface comfort was an independent predictor of mobilization progression. The pulmonary and oxygenation findings were exploratory and hypothesis-generating. These results support the deliberate selection of well-tolerated full-face interfaces in postoperative cardiac surgery care and warrant confirmation in multicenter trials with longer follow-up.