Perfluorocarbon-associated gas exchange (partial liquid ventilation) in respiratory distress syndrome: a prospective, randomized, controlled study.
OBJECTIVE
To determine the efficacy of perfluorocarbon-associated gas exchange (partial liquid ventilation) in respiratory distress syndrome.


METHODS
Prospective, randomized, controlled study.


METHODS
State University of New York at Buffalo, School of Medicine and Biomedical Sciences.


METHODS
Eleven premature lambs with respiratory distress syndrome, delivered by cesarean section.


METHODS
Five lambs were supported by conventional mechanical ventilation alone. Six lambs were switched to perfluorocarbon-associated gas exchange after 60 to 90 mins of conventional mechanical ventilation. Perfluorocarbon-associated gas exchange was accomplished by instilling a volume of liquid perfluorocarbon equivalent to normal functional residual capacity (30 mL/kg) into the trachea, performing 3 to 4 mins of tidal liquid ventilation, and, at end-expiration, with liquid functional residual capacity of 30 mL/kg remaining in the lung, reconnecting the animal to the volume ventilator for gas tidal volumes.


RESULTS
Serial arterial blood gases and lung mechanics were measured. While receiving conventional ventilation, all animals developed progressive hypoxemia, hypercarbia, and acidosis. However, in the perfluorocarbon-associated gas exchange group, within 5 mins of the initiation of perfluorocarbon-associated gas exchange, mean PaO2 increased four-fold, from 59 +/- 6 torr (7.9 +/- 0.8 kPa) during conventional ventilation to 250 +/- 28 torr (33.3 +/- 3.7 kPa; p < .05) during perfluorocarbon-associated gas exchange, and this increase was sustained at 60 mins of perfluorocarbon-associated gas exchange (268 +/- 38 torr; 35.7 +/- 5.1 kPa; p < .05). Mean PaCO2 decreased progressively from 62 +/- 4 torr (8.3 +/- 0.5 kPa) during conventional ventilation to 38 +/- 3.3 torr (5.1 +/- 0.4 kPa) at 60 mins of perfluorocarbon-associated gas exchange (p < .05). Mean pH concomitantly increased. Dynamic compliance increased three-fold within 15 mins of instituting perfluorocarbon-associated gas exchange, from 0.31 +/- 0.02 mL/cm H2O during conventional ventilation to 0.90 +/- 0.11 mL/cm H2O during perfluorocarbon-associated gas exchange, and this increase was sustained at 60 mins of perfluorocarbon-associated gas exchange (p < .05). Mean peak expiratory flow and mean expiratory resistance were essentially unchanged during perfluorocarbon-associated gas exchange as compared with conventional ventilation in the same group.


CONCLUSIONS
We conclude that perfluorocarbon-associated gas exchange, which employs liquid functional residual capacity and gas tidal volumes delivered by a conventional ventilator, can facilitate oxygenation and CO2 removal, and dramatically improve lung mechanics in the premature lamb with respiratory distress syndrome.
Leach
C L
CL
Department of Pediatrics, School of Medicine and Biomedical Science, State University of New York at Buffalo 14222.
Fuhrman
B P
BP
Morin
F C
FC
Rath
M G
MG
D000403:Airway Resistance; D000818:Animals; D000831:Animals, Newborn; D001784:Blood Gas Analysis; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D005260:Female; D005466:Fluorocarbons / Q000494:pharmacology / Q000627:therapeutic use*; D005652:Functional Residual Capacity; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007322:Instillation, Drug; D008170:Lung Compliance; D010366:Peak Expiratory Flow Rate; D011247:Pregnancy; D011659:Pulmonary Gas Exchange; D011897:Random Allocation; D012121:Respiration, Artificial / Q000295:instrumentation / Q000379:methods*; D012127:Respiratory Distress Syndrome, Newborn / Q000097:blood / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D015996:Survival Rate; D013990:Tidal Volume
D005466:Fluorocarbons