ABSTRACT
Objective To evaluate the efficacy of high frequency two-lung ventilation (TLV) with low tidal volume assisted by CO2 pneumothorax for airway management in patients undergoing thoracoscopic radical resection of esophagus cancer.Methods Thirty patients of both sexes,aged 48-64 yr,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,scheduled for elective thoracoscopic radical resection of esophagus cancer,were divided into 2 groups (n =15 each) using a random number table:onelung ventilation group (group O) and TLV group (group T).A left-sided double-lumen tube was inserted orally in group O,and a single-lumen tube was placed orally in group T.During thoracoscopic surgery,the left lung was ventilated,with tidal volume 8 ml/kg and respiratory rate 14 breaths/min in group O.In group T,artificial pneumothorax was induced by continuous CO2 insufflation with CO2 pressure at 10 mmHg,and bilateral lungs were ventilated,with tidal volume 5 ml/kg and respiratory rate 20 breaths/min.Mean arterial pressure and heart rate were recorded before induction of anesthesia,immediately after intubation (T1),at 10 min after intubation (T2),at 30 min after the start of thoracoscopic surgery (T3),immediately after the end of thoracoscopic surgery (T4) and at 30 min of TLV (T5).Arterial blood samples were collected for blood gas analysis at T2,T3,T4 and T5.The exposure of the surgical field and the number of lymph node dissection in the left recurrent laryngeal nerve chain were recorded during surgery.The emergence time,extubation time and time for recovery of consciousness were recorded.Results Arterial oxygen partial pressure was significantly lower at T3,4 than at T2 in the two groups,and arterial carbon dioxide partial pressure was significantly higher,and the pH value was lower at T3,4 than at T2 in group T (P＜0.05).Compared with group O,arterial carbon dioxide partial pressure was significantly increased,the pH value was decreased,and the number of lymph node dissection in the left recurrent laryngeal nerve chain was increased at T3,4 in group T (P＜0.05).There were no significant differences between the two groups in the good exposure of the surgical field,emergence time,extubation time and time for recovery of consciousness (P＞0.05).Conclusion High frequency TLV with low tidal volume when assisted by CO2 pneumothorax can serve as a feasible mode for airway management in patients undergoing thoracoscopic radical resection of esophagus cancer.