Intrathoracic Pressure Regulator Performance in the Setting of Hemorrhage and Acute Lung Injury

Abstract

Introduction: The intrathoracic pressure regulator (ITPR) is a device designed to enhance venous return to the heart and subsequently cardiac preload by inducing negative end expiratory pressure in mechanically ventilated patients. Previous preclinical studies have shown increased mean arterial pressure (MAP) and decreased intracranial pressure (ICP) with use of the device. The aim of this study was to evaluate the hemodynamic and respiratory effects of ITPR in a porcine polytrauma model of hemorrhagic shock and acute lung injury (ALI). Methods: Swine were anesthetized and underwent a combination of sham, hemorrhage, and/or lung injury. Our experimental groups included no injury with and without ITPR (ITPR, Sham), hemorrhage with and without ITPR (ITPR/Hem, Hem), and hemorrhage and acute lung injury with and without ITPR (ITPR/Hem/ALI, Hem/ALI). The ITPR device was started at a setting of -3 cmH2O and incrementally decreased by 3 cmH2O after 30 minutes on each setting with 15 minutes allowed for recovery between settings to a nadir of - 12 cmH2O. Vital signs and ventilator settings were recorded at baseline, following each injury, at the end of each respective ITPR setting, and at the end of each recovery period.Arterial blood gas measurements were obtained at baseline, following each injury, and at the end of recovery period. Of note, due to gasping (at pressures below -6 cmH2O) with the ITPR device, all animals were chemically paralyzed.

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Document Details

Document Type
Technical Report
Publication Date
Apr 30, 2019
Accession Number
AD1097142

Entities

People

  • Dario Jr Rodriquez
  • Grace M. Niziolek
  • Mackenzie C. Morris
  • Michael D Goodman
  • Richard D Branson
  • Rosalie Veile
  • Sabre Stevens-topie
  • Thomas C Blakeman

Tags

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Airway Management
  • Arteries
  • Blood
  • Cardiovascular Diseases
  • Cardiovascular Physiological Phenomena
  • Cardiovascular System
  • Health Services
  • Heart Rate
  • Hemorrhage
  • Hemorrhagic Shock
  • Pressure Regulators
  • Pulmonary Function
  • Regulators
  • Respiratory Physiological Phenomena
  • Vital Signs

Fields of Study

  • Medicine

Readers

  • Cardiovascular Physiology
  • Neurotrauma and Rehabilitation Medicine.