Pulmonary effects of positive end-expiratory pressure and fluid therapy in experimental lung injury.

Abstract

The separate effects of positive end-expiratory pressure (PEEP) and intravascular volume administration on the histopathologic lung injury were not investigated in experimental lung injury previously. The authors hypothesized that high PEEP and a restrictive volume therapy would yield the best oxygenation and the least degree of lung injury. Pigs (52.8 ± 3.4 kg) underwent saline lavage-induced lung injury. The animals were ventilated either with low PEEP (mean PEEP 9 to 12 cm H₂O) and liberal volume therapy using hydroxyethyl starch (LowP/Vol+) or high PEEP (mean PEEP 21 cm H₂O) combined with recruitment maneuvers and liberal (HighP/Vol+) or restrictive volume therapy (HighP/Vol-). After 6.5 hours, lung injury was determined by using a histopathologic score evaluating overdistension, edema, exsudation, and inflammation. When volume therapy was liberal, high PEEP (HighP/Vol+) improved the Pao₂/Fio₂ index (416 ± 80 mm Hg) compared to low PEEP (LowP/Vol+, 189 ± 55 mm Hg; P < .05) but there was no difference in the median (interquartile range) lung injury score: 1.6 (1.2-1.9) and 1.9 (1.4-2.0). High PEEP with restrictive volume therapy (HighP/Vol-) did not further improve oxygenation (400 ± 55 mm Hg) but ameliorated the degree of lung injury: 0.9 (0.8-1.4) (P < .05). In lavage-induced lung injury, high PEEP improved oxygenation, but restrictive volume administration markedly reduced the lung injury score, mainly by reduced edema.

• Authors: Markus Kredel, Ralf M Muellenbach, Nicolas Schlegel, Christian Wunder, Michael Klingelhöfer, Markus Lange, Norbert Roewer, Jens Waschke, Jörg Brederlau
• Journal: Experimental lung research (Exp Lung Res) Vol. 37 Issue 1 Pg. 35-43 (Feb 2011) ISSN: 1521-0499 [Electronic] England
• PMID: 21077780 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Hydroxyethyl Starch Derivatives
• Plasma Substitutes
• Sodium Chloride

Topics

• Animals
• Combined Modality Therapy
• Disease Models, Animal
• Female
• Fluid Therapy
• Hemodynamics
• Hydroxyethyl Starch Derivatives (pharmacology)
• Lung (pathology, physiopathology)
• Lung Compliance
• Lung Injury (etiology, pathology, physiopathology, therapy)
• Plasma Substitutes (pharmacology)
• Pneumonia (physiopathology, therapy)
• Positive-Pressure Respiration
• Pressure
• Pulmonary Edema (physiopathology, therapy)
• Respiratory Mechanics
• Respiratory Rate
• Severity of Illness Index
• Sodium Chloride
• Swine
• Time Factors