A novel method for assessment of airway opening pressure without the need for low-flow insufflation

BACKGROUND: Airway opening pressure (AOP) detection and measurement are essential for assessing respiratory mechanics and adapting ventilation. We propose a novel approach for AOP assessment during volume assist control ventilation at a usual constant-flow rate of 60 L/min. OBJECTIVES: To validate the conductive pressure (P(cond)) method, which compare the P(cond)—defined on the airway pressure waveform as the difference between the airway pressure level at which an abrupt change in slope occurs at the beginning of insufflation and PEEP—to resistive pressure for AOP detection and measurement, and to compare its respiratory and hemodynamic tolerance to the standard low-flow insufflation method. METHODS: The proof-of-concept of the P(cond) method was assessed on mechanical (lung simulator) and physiological (cadavers) bench models. Its diagnostic performance was evaluated in 213 patients, using the standard low-flow insufflation method as a reference. In 45 patients, the respiratory and hemodynamic tolerance of the P(cond) method was compared with the standard low-flow method. MEASUREMENTS AND MAIN RESULTS: Bench assessments validated the P(cond) method proof-of-concept. Sensitivity and specificity of the P(cond) method for AOP detection were 93% and 91%, respectively. AOP obtained by P(cond) and standard low-flow methods strongly correlated (r = 0.84, p < 0.001). Changes in SpO(2) were significantly lower during P(cond) than during standard method (p < 0.001). CONCLUSION: Determination of P(cond) during constant-flow assist control ventilation may permit to easily and safely detect and measure AOP. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13054-023-04560-0.