| Recruitment maneuver in experimental acute lung injury: the role of alveolar collapse and edema. | |
| | |
MedLine Citation:
|
PMID: 20818231 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
OBJECTIVE: In acute lung injury, recruitment maneuvers have been used to open collapsed lungs and set positive end-expiratory pressure, but their effectiveness may depend on the degree of lung injury. This study uses a single experimental model with different degrees of lung injury and tests the hypothesis that recruitment maneuvers may have beneficial or deleterious effects depending on the severity of acute lung injury. We speculated that recruitment maneuvers may worsen lung mechanical stress in the presence of alveolar edema. DESIGN: Prospective, randomized, controlled experimental study. SETTING: University research laboratory. SUBJECTS: Thirty-six Wistar rats randomly divided into three groups (n = 12 per group). INTERVENTIONS: In the control group, saline was intraperitoneally injected, whereas moderate and severe acute lung injury animals received paraquat intraperitoneally (20 mg/kg [moderate acute lung injury] and 25 mg/kg [severe acute lung injury]). After 24 hrs, animals were further randomized into subgroups (n = 6/each) to be recruited (recruitment maneuvers: 40 cm H₂O continuous positive airway pressure for 40 secs) or not, followed by 1 hr of protective mechanical ventilation (tidal volume, 6 mL/kg; positive end-expiratory pressure, 5 cm H₂O). MEASUREMENTS AND MAIN RESULTS: Only severe acute lung injury caused alveolar edema. The amounts of alveolar collapse were similar in the acute lung injury groups. Static lung elastance, viscoelastic pressure, hyperinflation, lung, liver, and kidney cell apoptosis, and type 3 procollagen and interleukin-6 mRNA expressions in lung tissue were more elevated in severe acute lung injury than in moderate acute lung injury. After recruitment maneuvers, static lung elastance, viscoelastic pressure, and alveolar collapse were lower in moderate acute lung injury than in severe acute lung injury. Recruitment maneuvers reduced interleukin-6 expression with a minor detachment of the alveolar capillary membrane in moderate acute lung injury. In severe acute lung injury, recruitment maneuvers were associated with hyperinflation, increased apoptosis of lung and kidney, expression of type 3 procollagen, and worsened alveolar capillary injury. CONCLUSIONS: In the presence of alveolar edema, regional mechanical heterogeneities, and hyperinflation, recruitment maneuvers promoted a modest but consistent increase in inflammatory and fibrogenic response, which may have worsened lung function and potentiated alveolar and renal epithelial injury. |
| | |
Authors:
|
Viviane R Santiago; Andréia F Rzezinski; Liliane M Nardelli; Johnatas D Silva; Cristiane S N B Garcia; Tatiana Maron-Gutierrez; Debora S Ornellas; Marcelo M Morales; Vera L Capelozzi; John Marini; Paolo Pelosi; Patricia R M Rocco |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: Critical care medicine Volume: 38 ISSN: 1530-0293 ISO Abbreviation: Crit. Care Med. Publication Date: 2010 Nov |
Date Detail:
|
Created Date: 2010-10-20 Completed Date: 2010-11-02 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 0355501 Medline TA: Crit Care Med Country: United States |
Other Details:
|
Languages: eng Pagination: 2207-14 Citation Subset: AIM; IM |
Affiliation:
|
Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Acute Lung Injury
/
complications,
pathology,
physiopathology,
therapy* Animals Collagen Type III / biosynthesis Continuous Positive Airway Pressure* Interleukin-6 / biosynthesis Kidney / pathology Liver / pathology Lung / pathology Microscopy, Electron, Transmission Pulmonary Alveoli / injuries, pathology, physiopathology Pulmonary Atelectasis / etiology*, therapy Pulmonary Edema / etiology*, therapy Rats Rats, Wistar Respiration, Artificial Respiratory Mechanics / physiology |
| Chemical | |
Reg. No./Substance:
|
0/Collagen Type III; 0/Interleukin-6 |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Cauliflower urinary bladder caused by multiple diverticula.
Next Document: Age still matters: Prognosticating short- and long-term mortality for critically ill patients with p...