Esophageal Pressure
ProcedureA transnasally placed esophageal balloon catheter was inserted. Following a positive-pressure occlusion test, end-inspiratory and end-expiratory esophageal pressures (Pes) were measured to estimate pleural pressure, thereby enabling the calculation of transpulmonary pressure in the non-dependent lung regions.Under conditions of homogeneous lung parenchyma, the physiological upper limit of transpulmonary pressure is 20 cmH₂O. To achieve this upper limit at end-inspiration in the non-dependent lung tissue, the lung recruitment pressure is calculated with the formula: P = 20 × ΔP / [ΔP - (Pes_insp - Pes_exp)], where the maximum pressure does not exceed 40 cmH₂O. Using the calculated pressure, a single-cycle recruitment maneuver is performed both 30 minutes after pneumoperitoneum establishment and before the end of surgery, each maintained for 10 seconds.
Other names: Transpulmonary Pressure, Pleural Pressure