Effects of Shenmai injection on intrapulmonary shunt during one-lung ventilation in patients undergoing thoracic surgery

Abstract

Objective To evaluate the effects of Shenmai injection on intrapulmonary shunt during one-lung ventilation in patients undergoing thoracic surgery.Methods Sixty ASA physical status Ⅰ or Ⅱ patients of both sexes,aged 40-60 yr,with body mass index of 18-25 kg/m2,scheduled for elective thoracic surgery,were randomly divided into 2 groups (n =30 each) using a random number table:control group (group C) and Shenmai injection group (group SM).Anesthesia was induced with midazolam,sufentanil,rocuronium,and etomidate.Starting from the end of induction of anesthesia until the time point immediately before one-lung ventilation,Shenmai injection 0.6 ml/kg (in 250 ml normal saline) was infused intravenously in SM group,and the equal volume of normal saline was given instead in C group.Immediately before one-lung ventilation,at 10 and 60 min of one-lung ventilation and at 10 min of two-lung ventilation,arterial and venous blood samples were collected for blood gas analysis and PaO2 was recorded.Intrapulmonary shunt (Qs/Qt) and alveolar-arterial oxygen pressure difference (P(A-a)DO2) were calculated.Results Compared with group C,PaO2 was significantly increased at 10 and 60 min of one-lung ventilation,and Qs/Qt and P(A-a)DO2 were decreased in group SM.Conclusion Shenmai injection 0.6 ml/kg infused intravenously before one-lung ventilation can reduce the intrapulmonary shunt during one-lung ventilation in patients undergoing thoracic surgery. Key words: Chinese herbs; Respiration, artificial; Pulmonary circulation