Comparison of airway pressure release ventilation with low tidal volume ventilation in patients with acute respiratory failure

Abstract

Background and aims:Acute respiratory failure (ARF) frequently requires invasive mechanical ventilation. Though low tidal volume ventilation has improved outcome of these patients, mortality is still high. We aimed to assess whether the use of Airway Pressure Release Ventilation (APRV) results in better oxygenation compared to Low Tidal Volume (LTV) ventilation in patients with ARF.

Methods: Patients with ARF requiring mechanical ventilation were randomized into either APRV or LTV ventilation. PaO₂ and PaO₂/FiO₂ ratio were recorded and compared between the groups for the assessment of effect on oxygenation.

Results: Two hundred and two patients were included in the study with 101 patients in each group. Baseline oxygenation status, APACHE II scores, and demographic parameters were similar in both the groups. PaO2 values at the time of admission (73.73 ± 22.23 mmHg in APRV group and 75.13 ± 20.43 mmHg in LTV group; p = 0.643), at 24 hours (176.21 ± 50.70 vs 180.62 ± 53.19 mmHg; p = 0.547) and at 72 hours (208.17 ± 61.20 vs 211.36 ± 50.89 mmHg; p = 0.688) were similar between the groups. The mean values of PaO₂/FiO₂ ratio at 0, 24, and 72 hours were 178.67 ± 55.51 vs 186.09 ± 53.34, 285.87 ± 69.08 vs 290.95 ± 63.56, and 288.95 ± 71.51 vs 283.78 ± 59.13 mmHg respectively in APRV and LTV groups.

Conclusion: Both APRV and LTV modes improved oxygenation and had similar effects on oxygenation in patients with ARF.