Esophageal Pressure Measurement in Acute Hypercapnic Respiratory Failure Due to Severe COPD Exacerbation Requiring NIV-A Pilot Safety Study.

Abstract

Esophageal pressure (Pes) measurements could optimise ventilator parameters in acute respiratory failure (ARF) patients requiring noninvasive ventilation (NIV). Consequently, the objectives of our study were to evaluate the safety and accuracy of applying a Pes measuring protocol in ARF patients with AECOPD under NIV in our respiratory intermediate care unit (RICU). An observational cohort study was undertaken. The negative inspiratory swing of Pes (ΔPes) was measured: in an upright/supine position in the presence/absence of NIV at D1 (day of admission), D3 (3rd day of NIV), and DoD (day of discharge). A digital filter for artefact removal was developed. We included 15 patients. The maximum values for ∆Pes were recorded at admission (mean ∆Pes 23.2 cm H2O) in the supine position. ∆Pes decreased from D1 to D3 (p < 0.05), the change being BMI-dependent (p < 0.01). The addition of NIV decreased ∆Pes at D1 and D3 (p < 0.01). The reduction of ∆Pes was more significant in the supine position at D1 (8.8 cm H2O, p < 0.01). Under NIV, ∆Pes values remained higher in the supine versus upright position. Therefore, the measurement of Pes in AECOPD patients requiring NIV can be safely done in an RICU. Under NIV, ∆Pes reduction is most significant within the first 24 h of admission.