Comparison of noninvasive respiratory support methods in the postoperative period in cardiac surgery patients: a prospective randomized trial

Abstract

INTRODUCTION: The frequency of respiratory failure in the postoperative period is 17–22 % [1–3]. The most commonly used methods: noninvasive positive pressure mask ventilation (NIPPMV), high-flow nasal cannula (HFNС), noninvasive positive pressure helmet ventilation (NIPPHV). OBJECTIVE: Comparison of the effectiveness of respiratory support methods depending on their effect on gas exchange in patients with mild to moderate respiratory failure in the early period after cardiac surgery. MATERIALS AND METHODS: The study included 42 cardiac surgery patients with 200 < P/F < 300 who were divided into 3 groups depending on the methods of respiratory support used (NIPPMV, HFNС, NIPPHV). The main point of the study is to assess the dynamics of the gas exchange indicators before, during and after their use. RESULTS: All three methods of NIVL contribute to a statistically significant improvement in gas exchange during NIVL, which persisted after the end of therapy (SpO2, PaO2, P/F, Qsp/Qt). In the group with the use of NIPPMV and HFNС an increase in the oxyhemoglobin fraction. In the course of this study, no data were revealed on changes in PaCO2. The largest increase in SpO2 was revealed in groups using a mask and helmet, but at the end of the NIVL session there were no statistically significant differences between the groups. A decrease in the proportion of patients with P/F < 300 after a single session in the NIPPMV group by 2 times, in the HFNC group — by 1.6 times, in the NIPPHV group — by 3.5 times. CONCLUSIONS: Conducting noninvasive respiratory support significantly improves the indicators of oxygenating lung function in the early postoperative period in cardiac surgery patients. NIPPHV and NIPPMV are more effective compared to HFNC. When using a helmet, a higher level of support is required.