Salvage therapies for refractory hypoxemia in ARDS

Respir Med. 2018 Aug:141:150-158. doi: 10.1016/j.rmed.2018.06.030. Epub 2018 Jul 3.

Abstract

Acute Respiratory Distress Syndrome (ARDS) is a condition of varied etiology characterized by the acute onset (within 1 week of the inciting event) of hypoxemia, reduced lung compliance, diffuse lung inflammation and bilateral opacities on chest imaging attributable to noncardiogenic (increased permeability) pulmonary edema. Although multi-organ failure is the most common cause of death in ARDS, an estimated 10-15% of the deaths in ARDS are caused due to refractory hypoxemia, i.e.- hypoxemia despite lung protective conventional ventilator modes. In these cases, clinicians may resort to other measures with less robust evidence -referred to as "salvage therapies". These include proning, 48 h of paralysis early in the course of ARDS, various recruitment maneuvers, unconventional ventilator modes, inhaled pulmonary vasodilators, and Extracorporeal membrane oxygenation (ECMO). All the salvage therapies described have been associated with improved oxygenation, but with the exception of proning and 48 h of paralysis early in the course of ARDS, none of them have a proven mortality benefit. Based on the current evidence, no salvage therapy has been shown to be superior to the others and each of them is associated with its own risks and benefits. Hence, the order of application of these therapies varies in different institutions and should be applied following a risk-benefit analysis specific to the patient and local experience. This review explores the rationale, evidence, advantages and risks behind each of these strategies.

Keywords: Acute respiratory distress syndrome; Lung; Refractory hypoxemia; Salvage therapies.

Publication types

  • Review

MeSH terms

  • Administration, Inhalation
  • Continuous Positive Airway Pressure / methods
  • Extracorporeal Membrane Oxygenation / methods
  • Humans
  • Hypoxia / complications*
  • Hypoxia / mortality
  • Hypoxia / therapy*
  • Neuromuscular Blocking Agents / therapeutic use
  • Nitric Oxide / administration & dosage
  • Nitric Oxide / therapeutic use
  • Observational Studies as Topic
  • Prone Position / physiology
  • Prostaglandins I / administration & dosage
  • Prostaglandins I / therapeutic use
  • Randomized Controlled Trials as Topic
  • Respiratory Distress Syndrome / etiology*
  • Respiratory Distress Syndrome / physiopathology
  • Risk Assessment
  • Salvage Therapy / methods*
  • Vasodilator Agents / administration & dosage
  • Vasodilator Agents / therapeutic use

Substances

  • Neuromuscular Blocking Agents
  • Prostaglandins I
  • Vasodilator Agents
  • Nitric Oxide