Better understand respiratory system mechanics
Insights from the inside. Esophageal pressure measurement
Esophageal pressure (Pes) measurement is a minimally invasive monitoring method, which enables us to determine the transpulmonary pressure.
The most common way to measure Pes is using an air-filled balloon integrated into an esophageal catheter.
Seeing is believing! Pes and Ptranspulm on the display
After you have connected the esophageal balloon catheter to the auxiliary port and confirmed the correct placement, the ventilator display shows esophageal pressure (Pes) and transpulmonary pressure (Ptranspulm) as a waveform.
You can measure static Ptranspulm using inspiratory and expiratory hold maneuvers.
PEEP setting based on transpulmonary pressure improved compliance and oxygenation in ARDS patients (Talmor D, Sarge T, Malhotra A, et al. Mechanical ventilation guided by esophageal pressure in acute lung injury. N Engl J Med. 2008;359(20):2095-2104. doi:10.1056/NEJMoa07086381).
Targeting positive transpulmonary pressure improved elastance and driving pressures, and may be associated with improved 28-day mortality (Baedorf Kassis E, Loring SH, Talmor D. Mortality and pulmonary mechanics in relation to respiratory system and transpulmonary driving pressures in ARDS. Intensive Care Med. 2016;42(8):1206-1213. doi:10.1007/s00134-016-4403-72).
Transpulmonary pressure measurement can avoid the use of ECMO in the most severe patients (Grasso S, Terragni P, Birocco A, et al. ECMO criteria for influenza A (H1N1)-associated ARDS: role of transpulmonary pressure. Intensive Care Med. 2012;38(3):395-403. doi:10.1007/s00134-012-2490-73).
A ventilation strategy guided by transpulmonary pressure may increase the proportion of patients with severe ARDS successfully weaned from ECMO (Wang R, Sun B, Li X, et al. Mechanical Ventilation Strategy Guided by Transpulmonary Pressure in Severe Acute Respiratory Distress Syndrome Treated With Venovenous Extracorporeal Membrane Oxygenation. Crit Care Med. 2020;48(9):1280-1288. doi:10.1097/CCM.00000000000044454).
Pes measurement is the gold-standard technique to assess respiratory effort and work of breathing (Bertoni M, Spadaro S, Goligher EC. Monitoring Patient Respiratory Effort During Mechanical Ventilation: Lung and Diaphragm-Protective Ventilation. Crit Care. 2020;24(1):106. Published 2020 Mar 24. doi:10.1186/s13054-020-2777-y5).