Pulmonary clearance of radiotracers after positive end-expiratory pressure or acute lung injury

Journal Article · Sun Jan 01 04:00:00 EST 1989 · J. Appl. Physiol.; (United States)

OSTI ID:6325114

Barrowcliffe, M P; Zanelli, G D; Jones, J G

In anesthetized rabbits we measured clearance from lung to blood of eight aerosolized technetium-99m-labeled compounds: diethylenetriaminepentaacetate (99mTc-DTPA); cytochrome c; myoglobin; a myoglobin polymer; albumin; and anionic, cationic, and neutral dextrans of equivalent molecular size. We investigated the effect of applying positive end-expiratory pressure (PEEP) and, on a subsequent occasion, of injecting oleic acid intravenously to produce acute lung injury on the pulmonary clearance rate. Base-line clearance rates were monoexponential and varied with the molecular weights of the radiotracers. For each tracer the rate of clearance was increased a similar degree by either PEEP or oleic acid. However, with PEEP, clearance remained monoexponential, whereas after oleic acid, smaller molecular-weight radiotracers had multiexponential clearance curves. This suggests that after oleic acid the alveolar epithelium breaks down in a nonuniform fashion. We conclude that differentiation of the effect of PEEP from that of severe lung injury caused by oleic acid is not readily accomplished by either increasing the size of the tracer molecule or by varying the molecular charge.

• Research Organization: Northwick Park Hospital, Harrow, Middlesex (England)
• OSTI ID: 6325114
• Journal Information: J. Appl. Physiol.; (United States), Journal Name: J. Appl. Physiol.; (United States) Vol. 66:1; ISSN JAPYA
• Country of Publication: United States
• Language: English

Related Subjects

550901* -- Pathology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALBUMINS
AMINO ACIDS
ANIMAL TISSUES
ANIMALS
ARTERIES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BLOOD SUBSTITUTES
BLOOD VESSELS
BODY
CARBOHYDRATES
CARBOXYLIC ACIDS
CARDIOVASCULAR SYSTEM
CHELATING AGENTS
CLEARANCE
CYTOCHROMES
DEXTRAN
DRUGS
DTPA
ELEMENTS
EPITHELIUM
EXCRETION
GLOBIN
HEMATOLOGIC AGENTS
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HOURS LIVING RADIOISOTOPES
INJURIES
INTERMEDIATE MASS NUCLEI
ISOMERIC NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LABELLED COMPOUNDS
LUNG CLEARANCE
LUNGS
MAMMALS
MOLECULAR WEIGHT
MONOCARBOXYLIC ACIDS
MYOGLOBIN
NONMETALS
NUCLEI
ODD-EVEN NUCLEI
OLEIC ACID
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANS
OXYGEN
PARTICLE SIZE
PIGMENTS
POLYSACCHARIDES
PORPHYRINS
PROTEINS
RABBITS
RADIOISOTOPES
RADIOPROTECTIVE SUBSTANCES
RESPIRATION
RESPIRATORY SYSTEM
SACCHARIDES
SIZE
TECHNETIUM 99
TECHNETIUM ISOTOPES
TISSUES
VERTEBRATES
YEARS LIVING RADIOISOTOPES