[Effects of recruitment maneuvers in prone position for pulmonary or extra-pulmonary acute respiratory distress syndrome on hemodynamics in dog].
OBJECTIVE
To evaluate the effect of recruitment maneuvers in prone positioning on hemodynamic in dogs with acute respiratory distress syndrome (ARDS) of pulmonary or extra pulmonary origin.


METHODS
Forty-eight mongrel dogs were randomly divided into 8 groups with six dogs in each group. Hydrochloric acid was instilled into trachea to reproduce pulmonary ARDS (ARDSp) and oleic acid was intravenously injected to produce extra-pulmonary ARDS (ARDSe). ARDSp and ARDSe dogs were divided into conventional mechanical ventilation group (group A), prone-position ventilation group (group B), sustained inflation (SI) group (group C) and prone-position ventilation + SI group (group D) respectively. Hemodynamic parameters were monitored before injury and 0, 2 and 5 hours after ARDS was reproduced.


RESULTS
(1) In group A and group C, central venous pressure (CVP) increased significantly at 5 hours after ARDSp. Five hours after the establishment of ARDSp, pulmonary arterial wedge pressure (PAWP) increased in group C and group D. Mean pulmonary arterial pressure (MPAP) increased remarkably in group A, group C and group D at 2 hours and 5 hours after onset of ARDSp. In group C, intrathoracic blood volume index (ITBI) decreased at 5 hours after the onset of ARDSp. In all the four groups, extravascular lung water index (EVLWI) increased sharply at 0, 2 and 5 hours after onset of ARDSp. In group B and group C, cardiac index (CI) decreased to a greater extent at 2 and 5 hours after onset of ARDSp. CI decreased at 2 hours after onset of ARDSp in group D with statistically significant difference at different time points (all P<0.05). (2) In all four groups, EVLWI increased sharply at 0, 2 and 5 hours after onset of ARDSe. In ARDSe model, there was no significant difference in other hemodynamic parameters between groups (all P>0.05).


CONCLUSIONS
There are less influence on hemodynamics when SI is performed in prone position, and it is even more significantly so in ARDS dogs.
Department of Critical Care Medicine, Nanjing Zhong-da Hospital and School of Clinical Medicine, Southeast University, Nanjing 210009, Jiangsu, China.
Qiu-Hua
QH
Chen
Yi
Y
Yang
Hai-Bo
HB
Qiu
Hong-Yang
HY
Xu
Tao
T
Guo
Xiao-Ting
XT
Xu
D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D006439:Hemodynamics; D008297:Male; D016684:Prone Position; D011897:Random Allocation; D012121:Respiration, Artificial; D012128:Respiratory Distress Syndrome / Q000503:physiopathology* / Q000628:therapy