Impact of the transpulmonary pressure on right ventricle impairment incidence during acute respiratory distress syndrome: a pilot study in adults and children

Abstract

Background: Right ventricle impairment (RVI) is common during acute respiratory distress syndrome (ARDS) in adults and children, possibly mediated by the level of transpulmonary pressure (P_L). We sought to investigate the impact of the level of P_L on ARDS-associated right ventricle impairment (RVI).

Methods: Adults and children (> 72 h of life) were included in this two centers prospective study if they were ventilated for a new-onset ARDS or pediatric ARDS, without spontaneous breathing and contra-indication to esophageal catheter. Serial measures of static lung, chest wall, and respiratory mechanics were coupled to critical care echocardiography (CCE) for 3 days. Mixed-effect logistic regression models tested the impact of lung stress (ΔP_L) along with age, lung injury severity, and carbon dioxide partial pressure, on RVI using two definitions: acute cor pulmonale (ACP), and RV dysfunction (RVD). ACP was defined as a dilated RV with septal dyskinesia; RVD was defined as a composite criterion using tricuspid annular plane systolic excursion, S wave velocity, and fractional area change.

Results: 46 patients were included (16 children, 30 adults) with 106 CCE (median of 2 CCE/patient). At day one, 19% of adults and 4/7 children > 1 year exhibited ACP, while 59% of adults and 44% of children exhibited RVD. In the entire population, ACP was present on 17/75 (23%) CCE. ACP was associated with an increased lung stress (mean ΔP_L of 16.2 ± 6.6 cmH₂O in ACP vs 11.3 ± 3.6 cmH₂O, adjusted OR of 1.33, CI95% [1.11-1.59], p = 0.002) and being a child. RVD was present in 59/102 (58%) CCE and associated with lung stress. In children > 1 year, PEEP was significantly lower in case of ACP (9.3 [8.6; 10.0] cmH₂O in ACP vs 15.0 [11.9; 16.3] cmH₂O, p = 0.03).

Conclusion: Lung stress was associated with RVI in adults and children with ARDS, children being particularly susceptible to RVI. Trial registration Clinical trials identifier: NCT0418467.

Keywords: Acute cor pulmonale; Acute respiratory distress syndrome; Lung stress; Pediatric acute respiratory distress syndrome; Right ventricle failure; Transpulmonary pressure.

Fig. 1

Flowchart

Fig. 2

Comparison of respiratory mechanics in patients older than one year of age with or without acute cor pulmonale. Each available measure of respiratory mechanics was coupled to the simultaneous cardiac ultrasound. Data are presented for A respiratory, B lung, and C chest wall mechanics in ultrasounds of adults (blue boxes) and children (white boxes), with or without acute cor pulmonale. The central bars represent the medians; the lower and upper ends of the box represent, respectively, the 1st and 3rd quartiles; the T-bars represent the 10th and 90th percentiles; circles are outliers; extreme outliers are not represented in the figure (n = 2 for the normalized C_L/kg, C_RS/kg, and C_CW/kg, n = 1 for ΔP_ES). * p < 0.01 when ACP compared to no ACP; p < 0.05 when ACP compared to no ACP. ACP, acute cor pulmonale; C_CW/kg, static compliance of the chest wall normalized per predicted body weight; C_L/kg, static compliance of the lungs normalized per predicted body weight; C_RS/kg, static compliance of the respiratory system normalized per predicted body weight; DeltaPaw, static airway driving pressure; DeltaPL, static transpulmonary driving pressure; DeltaPes, difference between end-inspiratory and end-expiratory oesophageal pressure; end-inspiratory Pes, value of oesophageal pressure at the end of the inspiratory hold; end-expiratory Pes, value of the oesophageal pressure at the end of the expiratory hold; end-inspiratory PL, end-inspiratory transpulmonary pressure (elastance-derived method); end-expiratory PL, end-expiratory transpulmonary pressure (direct method); PEEP, positive end-expiratory airway pressure; Pplat, airway plateau pressure