Effects of non-ventilated lung with nitrous oxide on intrapulmonary oxygenation and lactic acid level in arterial blood during one lung anesthesia / 中国病理生理杂志

ABSTRACT

AIM: To investigate the effects of non-ventilated lung with N_2O on systemic oxygenation and lactic acid level in arterial blood during one lung anesthesia. METHODS: Twenty-two patients, ASA Ⅰ-Ⅲ, scheduled for selective pulmonary surgery, were randomly divided into two groups control group (group A, n=11) and observation group (group B, n=11). Group A the non-ventilated lung was kept open to the air; group B N_2O 2 cmH_2O through CPAP system was insufflated into the non-ventilated lung during one lung ventilation. The anesthesia was induced with intravenous midazolam (0.05 mg?kg~(-1)), propofol (0.5-1.0 mg?kg~(-1)), fentanyl (4 ?g?kg~(-1)), and vecuronium (0.1 mg?kg~(-1)) and was maintained with inhaling isoflurane. Blood gas analysis and lactic acid was recorded 20 min after two-lung ventilation (TLV) in the supine position, 20 min after one-lung ventilation (OLV) in the supine position, 20 min and 40 min after OLV in the lateral position and at the end of operation and the shunt fraction was calculated. RESULTS: PaO_2 in group B was significantly higher than that in group A (P