ABSTRACT
ObjectiveTo evaluate the effectiveness of setting PEEP and tidal volume (VT ) according to pressure-volume (P-V) curve during one lung ventilation (OLV) in patients undergoing thoracic surgery.Methods Twenty-five ASA Ⅰ or Ⅱ patients of both sexes aged 44-64 yr weighing 57-75 kg undergoing lobectomy under general anesthesia were enrolled in this study.Double-lumen tube was inserted.Correct positioning was verified by flberoptic bronchoscopy.The patients were mechanically ventilated.P-V curve was measured by SSS system during OLV.Lower inflection point (LIP)and upper inflection point (UIP) were determined.The pressure at LIP (PLIP) and volume at UIP (VUIP) were measured.Bilateral lungs were ventilated for 30 min (T0) at first before OLV was started.PEEP was set at PLIP + 0.196 kPa and VT was set at VUIP,and the patients were ventilated for 30 min (T1).VT was then reduced to 80％ of VUIP.OLV was performed for another 30 min (T2).VT was then further reduced to 60％ of VUIP and the patients were ventilated for 30 min (T3).PEr CO2 was maintained at 4.67-6.00 kPa.Arterial blood and central venous samples were taken at T0-3.Blood gas analysis was performed.Qs/Qt was calculated.MAP,HR,CVP,peak airway pressure (Peak),airway resistance (Rsw) and lung compliance (CL) were measured and recorded at T0-3.ResultsHR,Ppeakk,Rsw and Qs/Qt were significantly increased while CL and PaO2 decreased at T1-3,CVP was significantly increased at T1.2 and MAP and PaCO2 were increased at T3 as compared with the baseline values at T0.Ppeak and Rsw were significantly decreased at T2.3 and PaO2 was significantly increased while Qs/Qt decreased at T2,CVP was decreased,MAP and PaO2 were increased at T3 as compared with the values at T1.ConclusionsMechanical ventilation with VT set at 80％ of VUIPandPEEPatPUIP+0.196kPa provides best ventilatory efficacy for OLV in terms of PaO2 and hemodynamics.
ABSTRACT
Objective To investigate the effect of intravenous injection of parecoxib before operation on the efficacy of postoperative analgesia in patients undergoiag thoracic surgery.Methods Ninety ASA Ⅰ -Ⅲ patients,aged 38-76 yr,weighing 44-82 kg,scheduled for thoracic surgery under general anesthesia combined with thoracic epidural block,were randomly divided into 3 groups(n = 30 each): group A,B and C.Epidttral anesthesia was performed at the T6-7 interspace before general anesthesia. Anesthesia was induced with sufentanyl 0.4 μg/kg,vecuronium 0.12 mg/kg and propofol 1.5-2.0 mg/kg.Double-lumen bronchial tube was inserted and the patients were mechanically ventilated.Group A received iv injection of normal saline 2 ml 30 min before skin incision.Group B received iv parecoxib sodium 40 mg after extubation.Group C received iv parecoxib sodium 40 mg 30 min before skin incision.Anesthesia was maintained with propofol,vecuronium,sufentanyl and lidocaine.The patients received patient-controlled epidural analgesia(PCEA)with ropivacaine and 0.5 μg/ml sufentanil after surgery.The VAS score was maintained≤ 3.The comfort level was evaluated with Bruggrmann comfort scale(BCS)at 4,12,24 and 48 h after operation.The consumption of sufentanil during operation and within 48 h after operation was recorded.The adverse reactions were also recorded.Results Compared with group A,the consumption of sufentanil was significantly decreased in group B and C,the BCS score was significantly increased at 4 h after operation in group B,and the BCS score was significantly increased at each time point and the consumption of sufentanil during operation was significantly decreased in group C(P ＜ 0.05).The BCS score was significantly higher,and the consumption of sufentanil during operation and within 48 h after operation was significantly lower in group C than in group B(P ＜ 0.05).There was no significance difference in the adverse reactions among the 3 groups(P ＞ 0.05).Conclusion Intravenous injection of parecoxib 40 mg before operation reduces the perioperative sufentanil consumption in patients undergoing thoracic surgery.