The Study In The Clinical Application Of Adapt Support Ventilation (ASV) Of Weaning Patients Of Postop

Objective To evaluate the clinical value of Adapt Support Ventilation (ASV) applicated in mechanical ventilation by the way in comparing with a conventional venting mode, Synchronized Intermittent Mandatory Ventilation (SIMV).Methods From April, 2007 to March, 2008, we took part Patients of Postop. treated in surgery intensive care unit in Tianjin medical university general hospital.all had been done endotracheal intubation and were postop. Patients. Their cardiorespiratory function, blood gas analysis (PaO₂≥80mmHg, PaCO₂≤50mmHg, PaO₂ /FiO₂≥200 mmHg ) , renal function ,Hepatic function were normal before operation,. All patients did not have lung infection signs before operation .and the operations were successful. All patients were randomly divided into two groups in which patients were treated with ASV and with SIMV modes. All patients were weaning in a standard procedure, patients' APACHE score, duration of mechanical ventilation ,results of weaning. In the mechanical ventilation period, also analyzed breathing mechanics consists of work of breathing(WOB), clogging press of airway(P_0.1), cross product of inspiratory time and pressure(PTP), and haemodynamics.Results The APACHE score , Preoperative cardiorespiratory function, condition of narcotization or operation of the two grous didn't have significant difference. When grou1(ASV) compared grou2(SIMV), Tidal Volume (VT) was higher(P<0.05),total breathing frequency(fT), peak voltage of airway(Ppeak), mean pressure of airway(Pmean) were obviously lower(P<0.05);The patients' work of breathing(WOB), clogging press of airway(P0.1), cross product of inspiratory time and pressure(PTP) were obviously lower(P<0.05). Incidence rate of endogenous positive end expiratory pressure(auto-PEEP) dropped down. The patients' tolerance to breathing machine significantly rose. Average duration of mechanical ventilation significantly reduced. Which showed the two groups possessed comparability. Each index of blood gas analysis, each index of haemodynamics such as mean arterial blood pressure(MBP), central venous pressure(CVP), cardiac output(CO) of the two groups didn't have significant difference(P>0.05). Complication of mechanical ventilation such as pulmonary barotrauma of the two groups didn't have significant difference(P>0.05),The weaning achievement ratio didn't have significant difference(P>0.05)..Conclusions Adapt Support Ventilation (ASV) mode can gain the same venting target as conventional ventilation , Synchronized Intermittent Mandatory Ventilation (SIMV),which autocontrols venting parameters on the basis of the patients' breathing mechanics. It is as same as SIMV in hemodynamics influence , weaning achievement ratio , mechanical ventilation complication ratio. But it is better than SIMV to cut down pressure of airway, to reduce work of breathing, to lower breathe drive of centre, and to cut down incidence rate of endogenous positive end expiratory pressure. ASV increases the patients' tolerance to breathing machine and shortened the average duration of mechanical ventilation.