High PEEP decreases hyaline membrane formation in surfactant deficient lungs.
Lung lavage was performed in 16 anaesthetized rabbits to produce surfactant-deficient lungs. This resulted in alveolar collapse, an arterial PO2 of less than 15 kPa on 100% oxygen and an inflection point on the inspiratory limb of the pressure-volume curve at an airway pressure of 8-10 mm Hg. One group of eight animals was then ventilated with a positive end-expiratory pressure (PEEP) equal to the pressure at the inflection point, whilst the second group of eight was ventilated with a PEEP 5 mm Hg less than the inflection point. Animals in the high PEEP group had a significantly greater arterial PO2 than those in the low PEEP group, but the mean survival time for each group was similar. However, there was a significantly greater incidence of hyaline membranes in the low PEEP group. Various mechanisms to explain these findings are discussed.
Argiras
E P
EP
Nuffield Department of Anaesthetics, Radcliffe Infirmary, Oxford.
Blakeley
C R
CR
Dunnill
M S
MS
Otremski
S
S
Sykes
M K
MK
D000818:Animals; D006801:Humans; D006819:Hyaline Membrane Disease / Q000473:pathology / Q000517:prevention & control*; D007231:Infant, Newborn; D008168:Lung / Q000473:pathology; D008176:Lung Volume Measurements; D010100:Oxygen / Q000097:blood; D011175:Positive-Pressure Respiration; D011663:Pulmonary Surfactants / Q000172:deficiency*; D011817:Rabbits
D011663:Pulmonary Surfactants; D010100:Oxygen