2.Effect of four different anesthetic techniques on oxygenation and intrapulmonary shunt during prolonged one-lung ventilation
Ying SUN ; Yi FENG ; Baxian YANG
Chinese Journal of Anesthesiology 1994;0(05):-
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.
3.Effects of thoracic epidural anesthesia on systemic oxygen supply-demand relationship during one-lung ventilation
Yi FENG ; Ying SUN ; Baxian YANG
Chinese Journal of Anesthesiology 1995;0(10):-
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.
4.The effect of epidural ropivacaine on arterial oxygenation and intrapulmonary shunt during one-lung ventilation
Yi FENG ; Ying SUN ; Baxian YANG
Chinese Journal of Anesthesiology 1994;0(03):-
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
5.Sedative properties of epidural anesthesia
Yi FENG ; Ying SUN ; Deshui YU
Chinese Journal of Anesthesiology 1994;0(05):-
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
6.Comparison of the effects of isoflurane and propofol in conjunction with thoracic epidural block on oxygenation and shunt fraction during one-lung anesthesia
Ying SUN ; Yi FENG ; Baxian YANG
Chinese Journal of Anesthesiology 1996;0(07):-
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.
9.Application of robotic system in gastrointestinal surgery.
Xin-Yu QIN ; Feng-Lin LIU ; Yi-Hong SUN
Chinese Journal of Gastrointestinal Surgery 2011;14(5):311-313
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
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10.Effect of dexmedetomidine on minimal induced dose of propofol and endotracheal intubation cardiovascular reaction
Hongwei SUN ; Ling YU ; Yi FENG ; Baxian YANG
Clinical Medicine of China 2014;30(11):1127-1130
Objective To investigate the effect of dexmedetomidine on minimal induced dose of propofol and cardiovascular responses to tracheal intubation.Methods A double-blind randomized controlled trial was conducted.Sixty patients who underwent elective laparoscopic surgery were randomly divided into the dexmedetomidine group (treatment group) and control group.Patients in treatment group were given dexmedetomidine at dose of 0.1 μg/kg · min for 10 min before anesthesia induction,and then infused with 0.4 μg/kg · h until the end.Sodium chloride injection was infused at the same rate in control group.After 10 minutes from the start of dexmedetomidine or sodium chloride injection,propofol was infused by 0.4 mg/kg · min.The dosage of propofol used was recorded when eyelash reflex disappearing,and BIS value in 40 to 60.Propofol was infusion at the same rate,and laryngoscope was incubated at 2 minutes after fentanyl and rocuronium were given.The alertness/sedation (OAA/S scores),mean arterial pressure (MAP),heart rate,pluse oxygen saturation (SpO2) and BIS values were recorded at baseline (before dexmedetomidine or sodium chloride injection infusion),5 and 10 minutes after dexmedetomidine or sodium chloride injection infusion,at the time of eyelash reflex disappearing,before endotracheal intubation,placing the laryngoscope,1,3 and 5 min after intubation.Results OAA/S scores and BIS values in the treatment group were significantly lower than that of control group at 5 minutes and 10 minutes after the dexmedetomidine or sodium chloride injection infusion(P <0.05).MAP in treatment group was higher than that of control group at the time of eyelash reflex disappearing,before endotracheal intubation,placing the laryngoscope,1,3 and 5 minutes after intubation (P <0.05).Heart rate in treatment group was lower than that of control group at 5 and 10 minutes after dexmedetomidine or sodium chloride injection infusion and before the endotracheal intubation(P < 0.05).There was no significant difference in terms of SpO2 between two groups (P > 0.05).When patients consciousness disappeared and BIS values were in 40-60,the minimum induced dose of propofol was (88.00 ± 25.91) mg in treatment group and (117.33 ± 25.45) mg in control group.The dosage of propofol treatment group was obviously less than control group (t =4.423,P < 0.05).Conclusion Dexmedetomidine reduces the minimum induced dose of propofol while maintaining more stable hemodynamic changes during anesthesia induction.However,there has no obvious inhibition effect on cardiovascular response to tracheal intubation.