Esophageal Manometry and Regional Transpulmonary Pressure in Lung Injury

Abstract

These data support the use of esophageal manometry in acute respiratory distress syndrome. Assuming correct calibration, expiratory Pl derived from Pes reflects Pl in dependent to middle lung, where atelectasis usually predominates; inspiratory Pl estimated from elastance ratio may indicate the highest level of lung stress in nondependent "baby" lung, where it is vulnerable to ventilator-induced lung injury.

Ventilatory support and mechanical properties of the fibrotic lung acting as a “squishy ball”

“…Monitoring P L through esophageal pressure assessment [27] has been proposed to identify patients with regional alveolar collapse at the end of expiration, suggested by a negative end-expiratory P L . Physiologic studies confirmed that P L estimated by esophageal manometry reflects the regional P L of dependent lung areas where atelectasis predominate [28,29]. Titrating PEEP to target a positive P L at end-expiration maximizes lung recruitment and improves respiratory mechanics and oxygenation in ARDS [30], but did not improve survival in ARDS when compared to empirical high PEEP [31].…”

Advanced respiratory monitoring in COVID-19 patients: use less PEEP!

“…Respiratory mechanics was assessed in COVID-19 patients admitted to the Radboud University Nijmegen Medical Center as part of standard patient care. Brief occlusions were performed to assess end-inspiratory and end-expiratory airway and transpulmonary pressures (absolute and elastance ratio method) and to calculate respiratory and lung compliances as previously described [3,4]. Dead space ventilation was assessed using two methods:…”

Guiding ventilation with transpulmonary pressure

“…As for the absolute values of P es , in line with a classical study [1], recent experiments in pigs and in human cadavers showed that the absolute value of the P es is highly reliable, provided that a proper technique is used [2]. There is, however, no unique value of P pl , and a gradient of pressure exists between the upper, anterior part of the pleural space when the patient is lying supine, also referred to as the 'non-dependent' pleural regions, vs. the dorsal, posterior part of the pleural space, also referred to as the 'dependent' pleural regions.…”

“…better oxygenation and better respiratory system compliance in patients with ARDS [5]. Our recent validation study (pigs and human cadavers) of P es using direct P pl sensor revealed that measured P es accurately reflects local P pl in the mid to dependent lung, adjacent to the oesophageal balloon [2]. Since lung collapse usually predominates in dependent lung in ARDS, setting PEEP using expiratory P es to prevent dependent atelectasis makes sense ( Fig.…”