Objective To investigate the changes in oxygenation and intrapulmonary shunt duringprolonged one-lung ventilation (OLV) and compare the effects of four different anesthetic techniques. MethodsForty ASAⅠ -Ⅱ patients (27 male, 13 female) aged 36-74 yr undergoing prolonged OLV during elective thoracicsurgery were randomly allocated to one of four groups: (1) isoflurane (GI, n = 10); (2) isoflurane + epidural(GIE, n =10); (3) propofol (GP, n = 10); (4) propofol + epidural (GPE, n = 10). Radial artery wascannulated and Swan-Ganz catheter was placed via right internal jugular vein before induction of general anesthesia.In group 2 and 4 an epidural catheter was inserted at T_(7-8) or T_(8-9) and advanced 3 .5-4.0 cm in the epidural spacecephalad. Epidural block was produced by a bolus of 0.5 % ropivacaine 7-9 ml followed by continuous infusion of0. 5 % ropivacaine at 3-5 ml?h~(-1). Anesthesia was induced with propofol 1 .0-1. 5 mg?kg~(-1), fentanyl 3?g?kg~(-1) andvecuronium 0. 1 mg?kg~(-1). A left-sided double-lumen tube was inserted and correct position was confirmed. Thepatients were mechenically ventilated. The ventilation collditions were FiO_2 = 100 %, V_T = 8-10 ml?kg~(-1), I: E =1: 5 and respiratory rate was adjusted to maintained P_(ET) CO_2 at 35-45 mm Hg during both two-lung ventilation(TLV) and OLV. Anesthesia was maintained with isoflurane inhalation in group 1 and 2 or continuous infusion ofpropofol in group 3 and 4 supplemented with intermittent i. v. boluses of fentanyl. MAP, HR, ECG, MPAP,CVP, continuous cardiac output (CCO), BIS and TOF were continuously monitored during anesthesia. BIS was maintained at 45-55. Arterial and pulmonary blood gases were analyzed before induction of anesthesia (T_1), 30min after TLV was started (T_2 ), and 5, 15, 30, 60, 120 and 180 min after OLV was started (T_(3-8)) and 30 minafter TLV was resumed (T_9 ). The Qs/Qt (shunt fraction) was calculated at T_(1-9) Results Qs/Qt was significantlyincreased after induction of general anesthesia and mechanical ventilation and increased further during OLVcompared with the baseline value (T_1) in all four groups. The calculated Qs/Qt values were highest at 15 min (T_4)or 30 min (T_5) of OLV and remained high for 30-60 min and then gradually decreasing. During OLV QS/Qt washigher in group 1 than in the other three groups (P0.05). Cardiac output was significantly higher in group 1 and 2 than thatin group 3 and 4 during OLV. Conclusion During prolonged OLV intrapulmonary shunt tends to decrease withincreasing oxygenation with time, regardless of anesthetic techniques employed. Isoflurane inhalation is associatedwith a signifficant increase in shunt fraction. Combined general and epidural anesthesia may induce greaterhemodynamic changes.

Objective To assess the influence of upper thoracic epidural anesthesia (TEA) on systemic oxygen supply-demand relationship during one-lung ventilation (OLV). Methods Twenty ASA Ⅰ-Ⅲ patients undergoing elective esophageal surgery were randomly divided into 2 groups : group Ⅰ general anesthesia (GI n = 10) and group Ⅱ combined general-epidural anesthesia (GIE n = 10). In both groups anesthesia was induced with propofol 1.5-2.0 mg?kg-1, fentanyl 3 ?g?kg-1 and vecuronium 0.1 mg?kg-1. The patients were intubated with double-lumen catheter. Correct positioning was verified by auscultation and fiberoptic bronchoscopy. Anesthesia was maintained with isoflurane (1.5-2.0% ) and intermittent i. v. boluses of fentanyl. BIS was maintained at 45-55 during operation. In GIE group epidural puncture was performed at T7-8 or T8-9. The catheter was advanced 3.5-4.0 ml in the epidural space cephalad. 0.5% ropivacaine was infused at 3-5 ml?h-1 during operation. Anesthetic block levels ranged from T2-4 to T10-12 . Radial artery was cannulated for BP monitoring and blood sampling and Swan-Ganz catheter was positioned in the pulmonary artery via right internal jugular vein. ECG, MAP, HR, CVP, continuous cardiac output index (CCI) and BIS were continuously monitored during anesthesia. Arterial and mixed venous blood samples were obtained before induction of anesthesia (T0 ), 30 min after intubation while two lungs were being ventilated (T1) at 15, 30, 60 and 120 min of OLV (T2-3) and 30 min after TLV was resumed (T6 ) . MAP, CVP, cardiac output index (CI) and arterial and mixed venous blood oxygen content were measured and oxygen supply (DO2) and consumption (VO2) were calculated at each time point. Results In GIE group MAP was significantly lower than that in GI group ( P 0.05). At 15, 30 and 60 min of OLV (T2-4) mixed venous oxygen saturation (SVO2 ) was significantly lower while VO2 significantly higher in group GIE than in group GI. Consequently DO2/ VO2 in group GIE was significantly lower than that in group GI. Conclusion Thoracic epidural anesthesia combined with general anesthesia increases oxygen consumption (VO2) and consequently decreases DO2/ VO2 during OLV.

Objective To determine the effect of of thoracic epidural block on arterial oxygenation and intrapulmonary shunt during one-lung ventilation(OLV).Methods Twenty-four ASA class I - Ⅱ patients undergoing prolonged periods of OLV during elective general thoracic surgery were divided into two groups: general anesthesia group(GA)(n=12) and general anesthesia + epidural block group(GE, n = 12). The patients were premedicated with only scopolamine 0.3mg. Radial artery was cannulated and Swan-Ganz catheter placed via right internal jugular vein under local anesthesia. Epidural block was performed at T7-8or T8-9 and a catheter was inserted and advanced in the epidural space cranially for 3.5-4 cm. General anesthesia was induced with propofol l.5mg?kg-1, fentanyl 3?g?kg-1 and vecuronium 0.1 mg?kg-1. Right or left-sided double-lumen endobronchial tube was placed blindly and the correct position was determined by a combination of unilateral clamping and unclamping and auscultation of the lungs. In GA group anesthesia was maintained with continuous infusion of propofol (150-200 ?g?kg-1?min-1 ) and intermittent IV boluses of fentanyl and vecuronium. BIS was maintained at 45-50. In GE group anesthesia was maintained with infusion of propofol(80 - 120 ?g?kg-1?min-1 ) and epidural block (a loading dose of 0.5% ropivacaine 7-9ml followed by epidural infusion of 0.5% ropivacaine 3-5 ml?h-1) .The patients were mechanically ventilated. VT = 8-10 ml?kg-1, FiO2 = 1, I: R = 1:1.5 and respiratory rate was adjusted to maintain PET CO2 at 35-45 mm Hg. During OLV the above parameters were maintained. ECG, HR, MAP, MPAP, CVP, continuous cardiac output, BIS and TOP were continuously monitored during operation. Blood samples were taken from radial artery and S-G catheter for blood gas analysis at following intervals: (1) during spontaneous breathing when the patients was a wake (baseline); (2) when the patient was placed in lateral position and the two lungs were being ventilated for 30 min(TLV 30 I) ; (3) 5,15, 30 and 60 minduring the course of OLV; (4) the two lungs were ventilated again for 30 min (TLV 30II) andQs/Qt was calculated. Results Venous admixture increased significantly after induction of anesthesia and during mechanical ventilation and increased further during OLV as compared with the baseline(P

Objective To investigate the potential sedative effects of epidural anesthesia and its mechanism. Methods Fifty ASA Ⅰ -Ⅱ patients aged 20-55yr, scheduled for gynecological surgery were studied. Patients whose body weight exceeded 95 kg or was less than 45kg were excluded. Alcoholics and those addicted to sedative or opiates were also excluded. The patients were unpremedicated. Before anesthesia the patients' radial artery was cannulated for continuous BP monitoring and blood sampling. ECG, BIS and HRV were continuously monitored. Epidural puncture was performed at L1-2 . A catheter was inserted in epidural space for 3-4cm in a cephalad direction. The patients were randomly divided into 3 groups: epidural lidocaine group (group E, n = 15); intravenous lidocaine group (group Ⅰ , n = 15) and control group (group C, n =20). In group E the patients received an iv bolus of lidocaine 1.5mg?kg-1 followed by a lidocaine infusion at a rate of 30mg?kg-1?min-1 and an epidural bolus of normal saline 15 ml; in group C the patients received an epidural bolus of NS 15 ml only. The intravenous lidocaine infusion in group I was designed to mimic systemic absorption of lidocaine from epidural space. 20 min after epidural lidocaine or saline administration, a propofol infusion was started at a rate of 150ml/h until the patients lost consciousness, The amount of propofol infused was recorded. Blood samples were taken before propofol infusion for determination of plasma level of lidocaine. Results The amount of propofol infused when the patients lost consciousness was (1.22 ?0.25) mg?kg-1 in group E, (1.62 ?0.22) mg?kg-1 in group I and (1.85?0.41) mg?kg-1 in control group. The amount of propofol infused in group E was significantly less than that n group I and C ( P

Objective To compare the effects of isoflurane and propofol on arterial oxygenation and intrapulmonary shunt during one-lung ventilation (OLV) when combined with continuous thoracic epidural block. Methods Twenty-four ASA Ⅰ -Ⅱ patients with normal ventilatory function undergoing elective thoracic surgery were enrolled in this study. Patients with abnormal cardiac, liver or kidney function were excluded. The patients were premedicated with scopolamine 0. 3mg I. M. .Epidural block was performed at T7-8 or T8-9 . An epidural catheter was placed and its position confirmed by epidural 1% lidocaine 5 ml. General anesthesia was induced with propofol l.5mg?kg-1, fentanyl 3?g?kg-1 and vecuronium 0.lmg?kg-1 . Double-lumen catheter was inserted and its correct position was confirmed by a combination of unilateral lung ventilation and auscultation in both supine and lateral position. The patients were mechanically ventilated. Tidal volume was set at 8-10 ml?kg-1, FiO2 = 1, I:E=1:1.5, RR=10-12bpm and PETCO2 was maintained between 35-45 mm Hg. The parameters remained unchanged during one-lung ventilation. The patients were assigned to one of two groups : propofol group and isoflurane group. Anesthesia was maintained with propofol infusion in propofol group and isoflurane inhalation in isoflurane group and BIS was maintained at 45-55. A bolus of 0.5 % ropivacaine 7-9ml was given epidurally followed by 0.5% ropivacaine infusion at a rate of 3-5ml?h-1 in both groups during maintenance of anesthesia. Besides ECG, BP and BIS, continuous cardiac output(CCO Baxter) was monitored during operation. Blood samples were taken from radial artery and pulmonary artery simultaneously before anesthesia when patients were lying supine and breathing spontaneously (T0 ), in lateral position when both lungs were ventilated (T1 ), at 5,15, 30, 60 min of one-lung ventilation(T2-5 ) and when both lungs were ventilated again for 30min(T6) for blood gas analysis. Qs/Qt was calculated.Results (1) The two groups were comparable with respect to demographic data. Propofol infusion was maintained at 4-6 mg?kg-1?h-1 in propofol group and end-tidal isoflurane was maintained between 0.3%-0.5% in isoflurane group. (2) Venous admixture increased significantly at T1 and further increased after T2 and reached its peak at T3(31.1% ?4.2%) in propofol group and at T4 (33.5% ? 7.8% ) in isoflurane group. Shunt fraction was significantly lower in propofol at T4-5 than that in isoflurane group. (3) PaO2 decreased significantly during OLV in both groups, but there was no significant difference in PaO2 between the two groups. Conclusions When combined with thoracic epidural block, intravenous propofol infusion exerts less effect on intrapulmonary shunt than isoflurane inhalation during OLV but there was no significant difference in arterial oxygenation between the two groups.

Combined Modality Therapy ; Digestive System Surgical Procedures ; methods ; Gastrointestinal Neoplasms ; surgery ; Humans ; Treatment Outcome

Bacterial Proteins ; metabolism ; Carbon-Sulfur Lyases ; metabolism ; Mouth ; microbiology ; Quorum Sensing ; Signal Transduction

Robotic system helps surgeons in performing surgery. Currently Da Vinci system is the most popular. Da Vinci system has been used for the stomach and bowel diseases in 27 cases(18 cases of stomach and 9 cases of colon and rectum) in the Zhongshan Hospital, Fudan University. Accurate preoperative staging is crucial, and Da Vinci system is advantageous in lymph node dissection, preservation of nerve plexus, and complete resection of mesorectum. Adoption of gastrointestinal tract reconstruction technique should depend on the operation and experience in surgery. Though Da Vinci system has limitations and the cost is high, it is believed to be the future trend.
Digestive System Surgical Procedures ; methods ; Humans ; Robotics ; methods

Adolescent ; Case-Control Studies ; Child ; Child, Preschool ; Heart Defects, Congenital ; blood ; immunology ; Humans ; Infant ; Lymphocyte Subsets ; Th1 Cells ; immunology ; Th2 Cells ; immunology

Objective To investigate the efficacy of centrally fixed eyeball for assessment of the depth of anesthesia in premature infants undergoing outpatient fundus examination. Methods Fifty eight premature infants undergoing examination of fundus of eyes were enrolled in this study. Their gestational age (from the first day of last menstruation period to birth) + after birth age (from birth to the day when examination of fundus of eyes was performed) = 44-64 weeks. The patients were randomly divided into 2 groups: Ⅰ group body movement (group M, n = 27) and Ⅱ group centrally fixed eyeball (group E, n = 31). Anesthesia was induced and maintained with isoflurane inhalation. The patients were breathing spontaneously. The eyelids were kept open with speculum after induction of anesthesia. The EC50 of sevoflurane concentration which could inhibit body movement or make eyeballs centrally fixed was determined by up-and-down sequential experiment. The initial isoflurane concentration was 3% in both groups. Each time the isoflurane concentration was increased/decreased by 0.5 %. 95 % confidence interval (CI) was calculated. The lowest SpO2, respiratory rate and coughing during maintenance of anesthesia were recorded. Results The EC50 of sevoflurane (95% CI) was 2.9% (2.2%-3.6%) in group M and 3.4%(2.6%-4.6%) in group E. Examination was successfully completed in all patients. No respiratory depression and coughing occurred during examination and no vomiting and coughing were observed during feeding at 1 h after recovery from anesthesia. No body movement occurred in 15 patients whose eyeballs were centrally fixed in group E. Conclusion Centrally fixed eyeball can be used as sign of appropriate depth of anesthesia for fundus examination in premature infants.