The Intervention Study Of Extracorporeal Membrane Oxygenation On Acute Respiratory Distress Syndrome In Dogs

Objective To observe the early lung protect effect of extracorporeal membrane oxygenation (ECMO) on acute respiratory distress syndrome induced by repeated lung lavage with normal saline in mongrel dogs.Methods Twenty healthy mongrel dogs were divided into two groups randomly, the auxiliary ventilation group and the group of auxiliary ventilation with extracorporeal membrane oxygenation. The models of acute respiratory distress syndrome were made by repeated lung lavage of dogs with normal saline:dogs were first anaesthetized and performed the tracheal intubation, then we injected the normal saline into the intubation quickly (lOml/kg body weight), next given assisting ventilation for two minutes, sucked it out by suction catheter, repeated the progress three times every twenty minutes. The dogs of the auxiliary ventilation group were ventilated by respirator, as control group. The other dogs were treated with ventilating by respirator as well as the external jugular vein-femoral vein mode extracorporeal membrane oxygenation, as experimental group. The mean arterial pressure(MABP), cardiac output(CO), mean airway pressure(MAP), partial pressure of oxygen(PaO2) of arterial blood and fraction of inspired oxygen (FiO2) of each dogs were monitored at the time of thirty minutes before the model were built, at the moment of the model established and eight hours, sixteen hours, twenty-four hours after the establishment. Twenty-four hours later, we measured the contents of Malondialdehyde (MDA) and Myeloper Oxidase (MPO) in lungs, calculated the wet-dry-rate and observed the pathological change of lungs.Results There were significant differences between two treatments on mean airway pressure in dogs (P<0.05), the differences of MAP between the two groups had statistically significant (P<0.05) at the moment of sixteen hours and twenty hours after the acute respiratory distress syndrome models were established, the MAP of the experimental group was lower than the control group; There were significant differences between two treatments on oxygenation index in dogs (P<0.05), the differences of OI between the two groups had statistically significant (P<0.05) at the moment of eight hours, sixteen hours and twenty hours after the acute respiratory distress syndrome models were established, the OI of the experimental group was higher than the control group; There were significant differences between two treatments on mean arterial pressure in dogs (P<0.05), the differences of MABP between the two groups had statistically significant (P<0.05) at the moment of eight hours, sixteen hours and twenty hours after the acute respiratory distress syndrome models were established, the MABP of the experimental group was higher than the control group; There were significant differences between two treatments on cardiac output in dogs (P<0.05), the differences of CO between the two groups had statistically significant (P<0.05) at the moment of sixteen hours and twenty hours after the acute respiratory distress syndrome models were established, the CO of the experimental group was higher than the control group; The contents of MDA and MAP in the lungs between the two groups had statistically significant (P<0.05), the contents of the experimental group were higher than the control group; The wet-dry-rate of the lungs between the two groups had statistically significant (P<0.05), the rate of the experimental group was smaller than the control group; The degree of lung injury of the experimental group was lower than the control group.Conclusions Extracorporeal membrane oxygenation (ECMO) can improve the pulmonary and circulation function effectively and relieve the cardiac and pulmonary burden of the early acute respiratory distress syndrome dogs induced by normal saline. ECMO has an effective protection on the lung.