Objective To evaluate the effect of preadministration phenylephrine on the hemodynamics result from oxytocin during caesarean section.Methods One hundred parturients,ASA Ⅰ-Ⅱ,with single baby at full term in vertex presentation scheduled for cesarean section under continuous epidural anesthesia were randomly divided into 4 groups,each group was 25 cases.All parturients received injection 10 U of oxytocin in the uterus after delivery,followed by an oxytocin rapid infusion of 10 U (less than 5 min),meanwhile,through the other intravenous channel,injection of phenylephrine 1 μ g/kg in group 1,2 μ g/kg in group Ⅱ,3 μ g/kg in group Ⅲ,while injection of 0.9％ sodium chloride 1 ml in groupⅣ as control.The mean arterial pressure (MAP) and heat rate (HR) at preanesthesia (T0),the time of oxytocin injection after dehvery (T1) and after oxytocin injection 30 s (T2),1 ain (T3),3 min (T4),5 ain (T5),10 min(T6) was recorded.Results There were no significant difference in MAP at T0 and clinical data among the groups (P ＞ 0.05).The level of MAP in group Ⅰ and Ⅳ at T3-T5 was significantly lower than that at T0[(82 ± 7),(79 +5),(83 ± 6) mm Hg(1 mm Hg =0.133 kPa) vs.(90 ± 7) mm Hg,(84 ±7),(76 ± 5),(82 ±7) mm Hg vs.(91 ±7) mm Hg] (P ＜0.05).The level of MAP in group Ⅲ at T2-T3 was significantly higher than that at T0[(93 ± 8),(103 ± 10)mm Hg vs.(91 ± 8) mm Hg] (P ＜ 0.05).Compared with group Ⅳ,the level of MAP in group Ⅱ at T3-T5 was significantly higher,the level of MAP in group Ⅲ at T2-T5 was significantly higher,there was significant difference (P ＜0.05).The level of HR had no significant difference in T0 among the groups (P ＞ 0.05).The level of HR in four groups at T3-T5 was significantly higher than that at T0[(98 + 12),(105 + 12),(96 + 9) times/ain vs.(79 ± 8) times/ain,(89 ± 10),(96 ± 13),(92 + 12) times/min vs.(80 ± 11) times/min,(88 ± 10),(94 ± 12),(90 ± 9) times/min vs.(83 ± 10) times/min,(94 ± 12),(112 ± 13),(102 ± 1 1) times/ain vs.(82 ± 9) times/min](P ＜ 0.05 or ＜ 0.01),and reached to peak value at T4(P＜ 0.01),then gradually declined to the baseline values (T1) except in group Ⅳ at T6.Compared with group Ⅳ,the level of HR in group Ⅲ and group Ⅲ was significantly decreased at T4-T5(P ＜ 0.05).The rate of MAP decrease range above 30％ in group Ⅳ was 24％(6/24),and significantly higher than that in group Ⅱ (0) and group Ⅲ (0),there was significant difference(P＜ 0.05).The rate of nausea in group Ⅳ was significantly higher than that in group Ⅱ and group Ⅲ,there was significant difference (P ＜0.05).The scores of Apgar scale after delivery 1,5 min had no significant difference among four groups (P ＞0.05).Conclusion Haemodynamic stability can be obtained by administration 2 μ g/kg of phenylephrine when parturients received injection 10 U of oxytocin in the uterus after delivery,and followed by an oxytocin rapid infusion of 10 U during cesarean section.

Objective To compare the effects of four different analgesia techniques on serum IL-6, IL-10 and heat shock protein 70 (HSP70) in patients after hysterectomy. Methods Forty-eight ASA Ⅰ-Ⅱ patients aged 32-54 yrs weighing 45-79 kg after hysterectomy were randomly divided into 4 groups ( n = 12 each): group Ⅰ received patient-controlled epidural analgesia (PCEA) with 0.2% ropivacaine + fentanyl 2 ?g?ml-1 + 0.008% ondansetron; group Ⅱ received patient-controlled intravenous analgesia (PCIA) with fentanyl 8 ?g?ml-1 + 0.008% ondansetron; group Ⅲ PCEA with 0.2% ropivacaine + tramadol 2 mg?ml-1 +0.008% ondansetron and group Ⅳ PCI A with tramadol 8 mg?ml-1 + 0.008% ondansetron. Both PCEA and PCIA were commenced with a loading dose of 5 ml. The PCA pump was set up with an 1 ml bolus with a 10 min lockout interval and a background infusion at 1 ml?h-1. Blood samples were taken before anesthesia (baseline) and at 2, 24, 48 and 72 h after surgery for determination of serum levels of IL-6, IL-10 and HSP 70.Results The changes in serum IL-6, IL-10 and HSP 70 concentrations were similar. Serum IL-6, IL-10 and HSP 70 levels were all increased after surgery in the 4 groups, and they reached a peak at 24 h after surgery. Serum IL-6 and HSP 70 levels at 24h after surgery were significantly lower in group Ⅰ and Ⅲ than in group Ⅱ and Ⅳ( P

Objective To evaluate the effect of preloading the epidural space with normal saline (NS) on the incidence of injury to blood vessel by epidural catheter placement for cesarean section. Methods One hundred and fifty parturients with a single baby at full term in vertex presentation scheduled for cesarean section under continuous epidural anesthesia were randomly divided into 3 groups ( n = 50 each): Ⅰ group control; Ⅱ group NS needle attached to a 5 ml syringe. Loss of resistance was used to identify the epidural space. In group Ⅰ no fluid was injected into the epidural space before insertion of catheter; while in group Ⅱ and Ⅲ NS 5 ml with or without whom blood or blood tinted fluid was withdrawn from epidural catheter was recorded. Results The number of patients in whom blood or blood tinted fluid was withdrawn from epidural catheter was significantly lower in group Ⅱand Ⅲ than in group Ⅰ but was not significantly different between group Ⅱ and Ⅲ. Conclusion Preloading the epidural space with 5 ml NS can reduce the incidence of injury to blood vessel induced by insertion of epidural

Objective To study the optimal dose of dexmedetomidine for preventing of shive-ring during caesarean section under epidural anesthesia.Methods One hundred and twenty ASA Ⅰ orⅡ parturients with a single baby at full term in vertex presentation,scheduled for caesarean section under continuous epidural anesthesia,were randomly divided into 4 groups (n=30 each):group D1, group D2,group D3 and group N (control group).After delivery of the baby,The group D1,group D2 and group D3 were received an intravenous infusion loading dose of 0.2μg/kg,0.5μg/kg and 0.8μg/kg of dexmedetomidine within 10 minutes respectively,and following with an intravenous infusion 0.4 μg·kg-1·h-1 of dexmedetomidine until peritoneal closure.The group N received an intravenous infusion 0.1 ml·kg-1·h-1 of normal saline.Results The incidence and degree of shivering in group D2 and group D3 were lower than those in group D1 and group N(P<0.05),but there were no statistics differences between group D2 and group D3.Conclusion Administration of dexmedetomidine can re-duce the occurrence of shivering during caesarean section under epidural anesthesia,and a loading dose of 0.5 μg/kg of dexmedetomidine is the optimal dose.

Objective To explore the neonatal effects and efficacy of dexmedetomidine on haemodynamics during cesarean section under general anesthesia.Methods Thirty-eight ASA Ⅰ or Ⅱ parturients with a single baby at full term in vertex presentation,scheduled for cesarean section under general anesthesia,were randomly divided into 2 groups (each group of 19 patients) by random digits table method:dexmedetomidine group and normal saline group.The patients in dexmedetomidine group received an intravenous infusion loading dose of 0.6 μ g/kg of dexmedetomidine,starting 10 min before induction of anesthesia,following with an intravenous infusion 0.4 μ g/ (kg ·h) of dexmedetomidine until peritoneal closure.The patients in normal saline group received an intravenous infusion of isovolumic of normal saline.Recording the systolic blood pressure (SBP),diastolic blood pressure (DBP) and heart rate (HR) before infusion (T0) and 10 min after the start of infusion (T1),at tracheal intubation (T2),at delivery of the baby (T3),15 min after delivery (T4),at end of operation (T5),at extubation (T6) and 15 min after extubation (T7).The blood of umbilical vein and umbilical artery was drawn for gas analysis,and the Apgar scores at 1 and 5 min were also recorded after delivery.Results The level of SBP,DBP and HR at T0 had no significant difference between two groups (P ＞ 0.05).In dexmedetomidine group,the level of SBP,DBP and HR were significantly higher at T2 than those at T0 [(136 ± 12) mmHg (1 mmHg =0.133 kPa) vs.(124 ± 9) mmHg,(83 ± 10) mmHg vs.(72 ± 6) mmHg,(93 ± 11) times/min vs.(81 ± 8) times/min] (P ＜ 0.05).In normal saline group,the level of SBP,DBP and HR at T2-6 [(151 ± 14),(137 ± 11),(132 ± 10),(132 ±9),(142± 13)mmHgvs.(125 ±9)mmHg;(94±13),(85±9),(80±8),(80±9),(86±11)mmHgvs.(74 ±7) mmHg; (122 ±15),(105 ±12),(90 ±9),(89 ± 10),(97 ±11) times/min vs.(81 ±9) times/min] were significantly lower (P ＜ 0.05).Compared with normal saline group,the level of SBP,DBP and HR were lower in dexmedetomidine group at T2-6(P ＜ 0.05).There were no significant difference not only about the blood gas analysis of umbilical vein and umbilical artery,but also about the Apgar scores at 1 and 5 min after delivery (P ＞ 0.05).Conclusion Administration of dexmedetomidine is effective in maintaining the maternal haemodynamic during the cesarean section under general anesthesia without adverse neonatal effects.

Objective To compare dexmedetomidine administered via different routes for epidural anesthesia during second cesarean section.Methods Sixty parturients who were at full term with a singleton fetus,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,aged 22-38 yr,weighing 58-84 kg,undergoing a second caesarean section under epidural anesthesia,were divided into 3 groups (n=20 each) using a random number table:Ⅳ infusion of dexmedetomidine conbined with epidural injection of ropivacaine group (VDER group),epidural injection of a mixture of ropivacaine and dexmedetomidine group (ERD group) and epidural injection of ropivacaine group (ER group).The epidural puncture was performed at L2,3.After identification of the epidural space and a negative aspiration test for blood or cerebrospinal fluid,the mixture of 0.75％ ropivacaine 15 ml and 0.9％ normal saline 2 ml was injected epidurally,and dexmedetomidine 1 μg/kg was intravenously infused for 10 min at the same time in VDER group;the mixture of 0.75％ ropivacaine 15 ml and 1 μg/kg dexmedetomidine 2 ml was injected epidurally in ERD group;the mixture of 0.75％ ropivacaine 15 ml and 0.9％ normal saline 2 ml was injected epidurally in ER group.The onset time of epidural block,maximum level ofepidural block,time to reach the maximum epidural block and time of sensory block were recorded.Ramsay sedation scores were assessed at 30 miu after the end of epidural administration,and intraoperative traction reaction was also assessed.The development of hypotension,bradycardia,respiratory depressim and shivering was observed.The number of patients in whom remifentanil was used before delivery and Apgar scores at 1 and 5 min after birth were recorded.Results Compared with VDER group and ER group,the onset time and time to reach the maximum epidural block were significantly shortened,and the time of sensory block was prolonged in ERD group (P＜0.05).Compared with ER group,the rate of satisfactory sedation was significantly increased,the number of patients in whom remifentanil was used before delivery was decreased,the degree of intraoperative traction reaclion was mitigated,and the incidence of respiratory depression and shivering was decreased (P＜0.05),and no significant change was found in Apgar scores at 1 and 5 min after birth in VDER and ERD groups (P＞0.05).Conclusion Both Ⅳ and epidural dexmedetomidine can enhance the efficacy of epidural anesthesia during second cesarean section,producing no adverse effects on neonates;epidural injection of a mixture of ropivacaine and dexmedetomidine provides faster onset and prolonged time of sensory block,which is helpful for postoperative analgesia.

Objective To investigate the placental transfer and neonatal effects of dexmedetomidine during the cesarean section under general anesthesia.Methods Thirty-eight nulliparous parturients,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,aged 22-37 yr,weighing 56-82 kg,who were at full term with a singleton fetus,scheduled for elective caesarean section under general anesthesia,were randomly divided into 2 groups (n=19 each) using a random number table:dexmedetomidine group (group D) and normal saline group (group N).In group D,dexmedetomidine was infused in a loading dose of 0.6 μg/kg starting from 10 min before induction of anesthesia,followed by an infusion of 0.4 μg · kg-1 · h-1 until peritoneal closure.Group N received the equal volume of normal saline.Blood samples were collected from the maternal artery (MA),umbilical vein (UV),and umbilical artery (UA) for blood gas analysis and for determination of plasma dexmedetomidine concentrations (CMA,CUV and CUA) by high-performance liquid chromatography-mass spectrometry,and CUV/CMA and CUA/CUV were calculated.Apgar scores were recorded at 1 and 5 min after delivery,and the occurrence of respiratory depression was also recorded.The I-D interval (the time from administration of anesthetics to delivery) and U-D interval (the time from incision of the uterus to delivery) were recorded.Results There were no significant differences in the blood gas analysis parameters in blood samples collected from the MA,UV and UA,I-D interval,U-D interval,and Apgar scores between the two groups (P＞0.05).No neonatal respiratory depression was found in both groups.In group D,CMA,CUV and CUA were 471±119,359±88 and (321±78) ng/ml,respectively,CUV/CMA was 0.76±0.06,and CUA/CUV was 0.89±0.03.Conclusion Although the metabolism of dexmedetomidine is little after easy placental transfer,dexmedetomidine has no adverse effects on the newborn during the cesarean section under general anesthesia.

Objective To evaluate the efficacy of dexmedetomidine mixed with ropivacaine for epidural anesthesia in the patients.Methods Forty-six patients, of ASA physical status Ⅰ or Ⅱ , aged 36-58 yr, weighing 48-77 kg, scheduled for elective hysterectomy under epidural anesthesia, were randomly divided into 2 groups (n =23 each) according to the random number table: normal saline + ropivacaine group (R group) and dexmedetomidine + ropivacaine group (DR group).Epidural anesthesia was performed at L2,3interspace.The catheter was inserted into the epidural space.A mixture of 0.75％ ropivacaine 15 ml and dexmedetomidine 1 μg/kg was injected epidurally in DR group.A mixture of 0.75％ ropivacaine 15 ml and normal sline 2 ml was injected epidurally in R group.The onset time of sensory block, maximum level of sensory block, and duration of sensory block were recorded.The modified Bromage scale, Ramsay sedation score and intraoperative traction reaction were assessed.The occurrence of dexmedetomidine-related cardiovascular events and respiratory depression, and epidural anesthesia-related adverse events within 2 h after operation was recorded.Results Compared with R group, the onset time of sensory block was significantly shortened, the duration of sensory block was prolonged, the maximum level of sensory block and Ramsay sedation score were increased, the degree of intraoperative traction reactions was lessened, and the incidence of shivering was decreased in DR group (P ＜ 0.05).No patients developed dexmedetomidine-related adverse events.Conclusion Epidural dexmedetomidine 1 μg/kg significantly optimize the efficacy of ropivacaine when used for epidural anesthesia in the patients.

Objective To compare the effects of four different analgesic techniques on hyperglycemia and stress response to abdominal hysterectomy so as to select a more reasonable analgesic model. Methods Forty-eight patients were randomly divided into four groups: groupⅠreceived 0.2% ropivacaine+fentanyl 2 ?g/mL+ 0.008% ondansetron for PCEA; groupⅡreceived fentanyl 8 ?g/mL+ 0.008% ondansetron for PCIA; groupⅢ received 0.2% ropivacaince+tramadol 2 mg/mL+0.008% ondansetron for PCEA and groupⅥ received tramadol 8 mg/mL+ 0.008% ondansetron for PCIA. The four groups all included loading dose of 5 mL, bolus of 1mL with lock time of 10 minutes and background 1 mL/h. The level of blood glucose, insulin and cortisol were observed at five points: before anesthesia, at 2nd hour, 24th hour, 48th hour and 72th hour after the end of surgery. Results All the four analgesic techniques produced satisfactory pain relieve. Hyperglycemia was inhibited more efficiently in groupⅠand group Ⅲ than in groupⅡ and groupⅥ(P

ObjectiveTo evaluate the effect of preloading epidural space with 0.9％ sodium chloride on the incidence of the injury to blood vessel by epidural catheter insertion for cesarean section.Methods One hundred uterogestation patients with single birth,ASA class Ⅰ - Ⅱ,underwent caesarean section and requested continuous epidural analgesia were divided into group P and group C with each 50 cases by random digits table.After identification of the epidural space,group C was inserted epidural catheter directly,and 5 ml of 0.9％ sodium chloride was injected into epidural space through the epidural needle in group P,while the syringe plunger was held closed for 20 s to make sure the solution spreaded sufficiently,following insertion the epidural catheter.Between the two groups,mean arterial pressure and heart rate were recorded prior to anesthesia,2 min after turn to the supine horizontal position after succeeded puncture,the time when the fetus were born and when the surgery were over.The cases with bloody fluid in the epidural puncture needle during puncture,or in the epidural catheter during catheter placement,fresh blood in the epidural catheter,and bloody fluid in caudal end of epidural catheter during extubation were recorded.ResultsThe changes of mean arterial pressure and heart rate were all in the normal range,there was no obvious difference between the two groups.The incidence of rates with bloody fluid in the epidural puncture needle during puncture and the bloody fluid in caudal end of epidural catheter during extubation in group P were significantly lower than those in group C [ 10％ (5/50) vs.26％ (13/50),22％ (11/50) vs.48％ (24/50),P ＜ 0.05 or ＜ 0.01 ].ConclusionPreloading epidural space with 5 ml 0.9％ sodium chloride can reduce the incidence of the injury to blood vessel induced by insertion of epidural catheter.