ABSTRACT
Objective To explore the expression of SP-A in surface active substance of sputum pulmonary of dysfunctional venti-latory weaning response patients and to study changes of expression of SP-A and oxygenation index ,arterial partial pressure of oxy-gen .Methods The mechanical ventilatory patients were divide into dysfunctional ventilatory weaning response group (group A) and easily weaning group(group B) ,then collected sputum from ventilators at different times :on the first day ,two and seven days after using ventilators .Used ELISA to test level of SP-A and oxygenation index ,arterial partial pressure of oxygen in sputum of group A and group B .Results For group A ,SP-A content oxygenation index and arterial partial pressure of oxygen were significantly less than those for group B(P0 .05) .Con-clusion Dysfunctional ventilatory weaning response and lung injury related to ventilator can be diagnosed early through the test of SP-A content in sputum ,which provides a brand-new way and method of treatment in dysfunctional ventilatory weaning response and lung injury related to ventilator .