Minimal Change in Cardiac Index With Increasing PEEP in Pediatric Acute Respiratory Distress Syndrome

Manpreet K Virk,Justin C Hotz,Robinder G Khemani,Wendy Wong,Christopher J L Newth,Patrick A Ross

doi:10.3389/fped.2019.00009

Abstract

Objective: To determine if increasing positive end expiratory pressure (PEEP) leads to a change in cardiac index in children with Pediatric Acute Respiratory Distress Syndrome ranging from mild to severe.Design: Prospective interventional study.Setting: Multidisciplinary Pediatric Intensive Care Unit in a University teaching hospital.Patients: Fifteen intubated children (5 females, 10 males) with a median age of 72 months (IQR 11, 132) and a median weight of 19.3 kg (IQR 7.5, 53.6) with a severity of Pediatric Acute Respiratory Distress Syndrome that ranged from mild to severe with a median lung injury score of 2.3 (IQR 2.0, 2.7).Measurements: Cardiac index (CI) and stroke volume (SV) were measured on baseline ventilator settings and subsequently with a PEEP 4 cmH2O higher than baseline. Change in CI and SV from baseline values was evaluated using Wilcoxon signed rank test.Results: A total of 19 paired measurements obtained. The median baseline PEEP was 8 cmH2O (IQR 8, 10) Range 6–14 cmH2O. There was no significant change in cardiac index or stroke volume with change in PEEP. Baseline median CI 4.4 L/min/m2 (IQR 3.4, 4.8) and PEEP 4 higher median CI of 4.3 L/min/m2 (IQR 3.6, 4.8), p = 0.65. Baseline median SV 26 ml (IQR 13, 44) and at PEEP 4 higher median SV 34 ml (IQR 12, 44) p = 0.63.Conclusion: There is no significant change in cardiac index or stroke volume with increasing PEEP by 4 cmH2O in a population of children with mild to severe PARDS.Clinical Trial Registration: The study is registered on Clinical trails.gov under the Identifier: NCT02354365.

Highlights

Pediatric Acute Respiratory Distress Syndrome (PARDS) comprises a small fraction of critically ill children but continues to have high mortality up to 30–35% in severe PARDS patients [1,2,3]
A recent study has shown positive end-expiratory pressure (PEEP) is often conservatively applied in PARDS, which may be associated with harm [6]
There was no significant change in median indexed oxygen delivery (D’O2I) between baseline PEEP [493 ml/min/m2 (IQR 446, 687)] and PEEP 4 cmH2O higher [527 ml/min/m2 (IQR 471, 672)] (p = 0.98)

Summary

Introduction

Pediatric Acute Respiratory Distress Syndrome (PARDS) comprises a small fraction of critically ill children but continues to have high mortality up to 30–35% in severe PARDS patients [1,2,3]. There have been very few subsequent investigations of the impact of PEEP on cardiac output in children with ARDS, and recent recommendations by the Pediatric Acute Lung Injury Consensus Conference (PALICC) stress the importance of monitoring the cardiac output and oxygen delivery with PEEP titration for PARDS but that it is a research priority to further evaluate the hemodynamic and potential barotrauma effects of higher PEEP titration [10, 11]. It is possible given the recent findings delineating potential deleterious effects of PEEP [6] lower than ARDSNet protocol in PARDS along with the potential employment of transpulmonary pressure measurements to determine PEEP application in ARDS [12] PEEP levels higher than previously used will be applied in pediatric ARDS management

Methods

Results

Conclusion