Distribution of pulmonary blood flow and total lung water during partial liquid ventilation in acute lung injury.
BACKGROUND
Gas exchange is improved during partial liquid ventilation (PLV) with perfluorocarbon in animal models of acute lung injury. The mechanisms are not fully defined. We hypothesize that redistribution of pulmonary blood flow (PBF) along with redistribution of, and decrease in, total lung water (TLW) during PLV may improve oxygenation.


METHODS
We characterized PBF and TLW in anesthetized adult dogs by using positron emission tomography with H2(15)O. Measurements of gas exchange, PBF, and TLW were made before and after acute lung injury was induced with intravenous oleic acid. The same measurements were made during PLV (with 30 ml/kg perfluorocarbon) and compared with gas ventilated (GV) controls.


RESULTS
Oxygenation was significantly improved during PLV. PBF redistributed from the dependent zone of the lung to the nondependent zones, thus potentially improving ventilation/perfusion relationships. However, a similar pattern of PBF redistribution was observed during GV such that there was no significant difference between groups. TLW redistributed in a similar pattern during PLV. By quantitative measurements, PLV ameliorated the continued accumulation of TLW compared with GV animals.


CONCLUSIONS
We conclude that PBF and TLW redistribution and attenuation of increases in TLW may contribute to the improvement in gas exchange during PLV in the setting of acute lung injury.
Gauger
P G
PG
Department of Surgery, University of Michigan Medical School, Ann Arbor, USA.
Overbeck
M C
MC
Koeppe
R A
RA
Shulkin
B L
BL
Hrycko
J N
JN
Weber
E D
ED
Hirschl
R B
RB
D000818:Animals; D001834:Body Water / Q000502:physiology*; D004285:Dogs; D005466:Fluorocarbons; D008168:Lung / Q000000981:diagnostic imaging / Q000502:physiology*; D055370:Lung Injury; D010104:Oxygen Radioisotopes; D011652:Pulmonary Circulation / Q000502:physiology*; D012123:Pulmonary Ventilation; D012039:Regional Blood Flow; D013997:Time Factors; D014055:Tomography, Emission-Computed
D005466:Fluorocarbons; D010104:Oxygen Radioisotopes