Perfluorocarbon-associated gas exchange in gastric aspiration.
OBJECTIVE
To test whether perfluorocarbon-associated gas exchange (gas ventilation of the perfluorocarbon-liquid filled lung) could support oxygenation better than conventional positive pressure breathing in a piglet model of gastric aspiration-induced adult respiratory distress syndrome (ARDS).


METHODS
Prospective, randomized, blinded, controlled study.


METHODS
A critical care research laboratory in a university medical school.


METHODS
Fourteen healthy piglets.


METHODS
Under alpha-chloralose anesthesia and metocurine iodide neuromuscular blockade, 14 piglets underwent tracheostomy; central venous, systemic and pulmonary arterial catheterizations; and volume-regulated continuous positive-pressure breathing. Homogenized gastric aspirate (1 mL/kg) titrated to pH of 1.0 was instilled into the tracheostomy tube of each subject at 0 min to induce ARDS. Hemodynamics, lung mechanics, and gas exchange were evaluated every 30 mins for 6 hrs. Seven piglets were treated at 60 mins by tracheal instillation of perflubron, a volume selected to approximate normal functional residual capacity, and were supported by perfluorocarbon-associated gas exchange without modifying ventilatory settings. Perflubron was added to the trachea every hour to replace evaporative losses.


RESULTS
There was a significant difference in oxygenation over time when tested by repeated-measures analysis of variance (F test = 8.78, p < .01). On further analysis, the differences were not significant from baseline to 2.5 hrs but became increasingly significant from 2.5 to 6 hrs after injury (p < .05) in the inflammatory phase of gastric aspiration-induced ARDS. Histologic evidence for ARDS in the treated group 6 hrs after injury was lacking.


CONCLUSIONS
In the piglet model, perfluorocarbon-associated gas exchange with perflubron facilitates oxygenation in the acute phase of gastric aspiration-induced inflammatory ARDS when compared with conventional positive-pressure breathing. Histologic and physiologic data suggest that perfluorocarbon-associated gas exchange with perflubron might prevent ARDS if instituted after aspiration in the time window before the acute inflammatory process is manifest.
Nesti
F D
FD
School of Medicine and Biomedical Sciences, State University of New York at Buffalo.
Fuhrman
B P
BP
Steinhorn
D M
DM
Papo
M C
MC
Hernan
L J
LJ
Duffy
L C
LC
Fisher
J E
JE
Leach
C L
CL
Paczan
P R
PR
Burak
B A
BA
D000704:Analysis of Variance; D000818:Animals; D005466:Fluorocarbons / Q000494:pharmacology*; D006439:Hemodynamics / Q000502:physiology; D011015:Pneumonia, Aspiration / Q000503:physiopathology; D011446:Prospective Studies; D011659:Pulmonary Gas Exchange / Q000187:drug effects*; D011897:Random Allocation; D012128:Respiratory Distress Syndrome / Q000503:physiopathology*; D012129:Respiratory Function Tests; D016037:Single-Blind Method; D013552:Swine; D013997:Time Factors
D005466:Fluorocarbons