Prone position reverses gravitational distribution of perfusion in dog lungs with oleic acid-induced injury

Journal Article · Sun Apr 01 04:00:00 EDT 1990 · Journal of Applied Physiology (1985); (USA)

OSTI ID:6705146

Wiener, C M; Kirk, W; Albert, R K ^[1]

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1. Veterans Administration Medical Center, Seattle, WA (USA)

Although oxygenation improves in patients with the adult respiratory distress syndrome and in animals with oleic acid- (OA) induced acute lung injury when they are turned from the supine to the prone position, the mechanism(s) by which this improvement occurs is not known. Several groups have speculated that this improvement results from preferential edema accumulation in the dorsal lung regions and redistribution of perfusion away from these regions when the patients are turned to the prone position. We used radiolabeled microspheres to measure the regional distribution of perfusion (Qr) to the dorsal, mid, and ventral lungs of eight dogs in vivo in the supine and prone positions, before and after inducing acute lung injury with OA, and correlated the Qr observed after injury with the degree of regional extravascular lung water (EVLWr). Before OA, Qr increased along the gravitational gradient when the animals were supine but was more uniformly distributed when they were prone. After OA, Qr again followed a gravitational gradient when the animals were supine but was preferentially distributed to the nondependent regions when they were prone. EVLWr was similar in all regions, regardless of whether OA was injected when the animals were supine or prone. The gravitational Qr gradient is markedly reduced in the prone position, both before and after lung injury. The prone position-induced improvement in oxygenation is not the result of redistribution of Qr away from areas in which edema preferentially develops.

• OSTI ID: 6705146
• Journal Information: Journal of Applied Physiology (1985); (USA), Journal Name: Journal of Applied Physiology (1985); (USA) Vol. 68:4; ISSN JAPHE; ISSN 8750-7587
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMALS
BODY
CARBOXYLIC ACIDS
CERIUM ISOTOPES
DISEASES
DOGS
EDEMA
ELEMENTS
ISOTOPE APPLICATIONS
ISOTOPES
LUNGS
MAMMALS
MICROSPHERES
MONOCARBOXYLIC ACIDS
NONMETALS
OLEIC ACID
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
OXYGEN
PATHOLOGICAL CHANGES
PERFUSED ORGANS
POSITIONING
RARE EARTH ISOTOPES
RESPIRATORY SYSTEM
RESPIRATORY SYSTEM DISEASES
RUTHENIUM ISOTOPES
SYMPTOMS
THERAPY
TRACER TECHNIQUES
VERTEBRATES