Assessment of nasal pressure swing predicts respiratory support dependency in patients with hypoxic respiratory failure

Abstract

Background

Monitoring is essential in managing acute hypoxemic respiratory failure (AHRF). Nasal pressure swing (P_nose) may predict high-flow nasal oxygen (HFNO) therapy failure and respiratory support dependency. This study investigates P_nose's predictive value for respiratory support needs and clinical outcomes in AHRF patients initially treated with HFNO.

Methods

This post-hoc analysis included 60 AHRF patients treated with HFNO. Respiratory variables, including P_nose, were assessed at baseline and two hours after HFNO initiation. Patients were classified into high (HG) and low (LG) Pnose groups based on a 5.1 cmH2O threshold. The primary outcome was RS-free survival at day 7; HFNO failure, escalation to non-invasive ventilation (NIV) or mechanical ventilation (MV), mortality, and HFNO weaning time were also analyzed. Predictive accuracy of respiratory indices, including P_nose, was evaluated.

Results

Out of the patients enrolled, 35 were in the HG, and 25 in LG group. HG patients showed a lower RS-free survival at day 7 (adjusted HR=0.26, p < 0.0001), and experienced higher failure rates of HFNO (88 % versus 0 %, p < 0.0001), escalation to NIV (84 % versus 0 %, p < 0.0001), endotracheal intubation (36 % versus 0 %, p < 0.0001), and mortality (24 % versus 6 %, p = 0.0001) compared to LG. Accordingly, RS-free days at day 28 were lower in HG (11 days versus 23 days, p < 0.0001). Finally, among the respiratory variables, P_nose resulted independently associated with the primary outcome (OR=0.64 95 %CI [0.42–0.90], p = 0.02).

Conclusions

In patients with AHRF admitted to the ward and treated by HFNO, P_nose is an independent and accurate factor in forecasting the dependency from RS and survival within the first week.