[Assessment of early-stage physiological response to acute lung injury in canine models using balloon catheter system for measuring esophageal and gastric pressure].
OBJECTIVE
To explore feasible and reliable methods for estnbolishment and of acute lung injury model in animal models.


METHODS
Twenty-four healthy adult mongrel dogs with oleic acid-induced acute lung injury were evaluated for early-stage physiological response to acute lung injury using a balloon catheter system for measuring esophageal and gastric pressure.


RESULTS
In canine models of early-stage oleic acid-induced acute lung injury that sustained spontaneous breathing, in terms of respiratory mechanics, some parameters obviously increased including the respiratory rate (RR), minute ventilation (VE), peak inspiratory volume (Vinsp, peak), mean inspiratory volume (VT/Ti), inspiratory airway resistance (Raw, insp) (P<0.001 for all the parameters), with also significantly increased peak transdiaphragmatic pressure (Pdi, peak, P=0.0185). The tidal volume (VT) and dynamic lung compliance (CL,dyn), however, were significantly decreased (P<0.001), and significant variation occurred in the ratio of inspiratory time to duration of one breath (Ti/Ttot, P=0.163). In terms of gas exchange, the pH, PaO(2), SaO(2), PaO(2)/FiO(2), and end tidal partial pressure of carbon dioxide (PETCO(2)) all evidently declined (P<0.001), but PaCO(2) and ratio of alveolar dead space to tidal volume [VD(alv)/VT] increased significantly (P<0.001).


CONCLUSIONS
Application of balloon catheter system for measuring esophageal and gastric pressures allows objective evaluation of the various physiological responses in early stage of acute lung injury.
Chen
Xin
X
Department of Respiratory Diseases, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China. beijixingmiler@263.net
Chen
Rong-Chang
RC
Cen
Yan-Yi
YY
Yu
Hua-Peng
HP
Zhong
Nan-Shan
NS
D055371:Acute Lung Injury / Q000503:physiopathology* / Q000628:therapy*; D000818:Animals; D002404:Catheterization; D004195:Disease Models, Animal; D004285:Dogs; D004947:Esophagus; D005240:Feasibility Studies; D005260:Female; D008297:Male; D011312:Pressure; D015203:Reproducibility of Results; D015656:Respiratory Mechanics / Q000502:physiology; D013270:Stomach; D013997:Time Factors