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Objective To evaluate the modifiying efficacy of pectoral nerve ( Pecs) block com-bined with general anesthesia in patients undergoing radical mastectomy. Methods A total of 60 American Society of Anesthesiologists physical status Ⅰ or Ⅱ female patients, aged 40-64 yr, weighing 50-70 kg, scheduled for elective radical mastectomy, were divided into 2 groups ( n= 30 each) using a random num-ber table method: general anesthesia group ( group GA) and Pecs block combined with general anesthesia group ( group PB+GA) . The patients in group PB+GA received Pecs block guided by ultrasound. After the needle was advanced to the pleura plane between the pectoralis major and minor, 0. 33％ ropivacaine 15 ml was injected, and 0. 33％ ropivacaine 30 ml was injected into the surface of the serratus anterior muscle at the level of the third rib. Anesthesia was induced by intravenous injection of midazolam, propofol, sufen-tanil and cisatracurium and maintained by target-controlled infusion of propofol and intermittent intravenous boluses of sufentanil and cisatracurium. Bispectral index value was maintained at 40-60. Patient-controlled intravenous analgesia was performed with sufentanil at the end of surgery. Immediately after anesthesia in-duction, at 30 min and 2 h after skin incision, and at 2, 6 and 24 h after operation, peripheral venous blood samples were collected for determination of the concentrations of plasma epinephrine by radioimmuno-assay, and the blood samples were collected from the end of the finger at the same time for determination of blood glucose concentrations. The consumption of intraoperative sufentanil, emergence time, pressing times of patient-controlled analgesia ( PCA) and development of nausea and vomiting within 24 h after operation were recorded. Results Compared with group GA, blood glucose and plasma epinephrine concentrations were significantly decreased, the intraoperative sufentanil consumption was reduced, the emergence time was shortened, the pressing times of PCA were decreased at 2, 6 and 24 h after operation ( P<0. 05) , and no significant change was found in the incidence of postoperative nausea and vomiting in group PB+GA ( P>0. 05). Conclusion When Pecs block combined with general anesthesia is used in the patients undergoing radical mastectomy, it is helpful in reducing the opioid consumption and more helpful in inhibiting postoper-ative stress responses and pain responses than general anesthesia alone.
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Objective To determine the median effective dose (ED50) of oxycodone inhibiting responses to laryngeal mask airway (LMA) insertion when combined with propofol in the adult female patients.Methods Female patients,aged 18-60 yr,with body mass index of 18-24 kg/m2,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,scheduled for elective gynecologic surgery,were included.ED50 of oxycodone was determined by up-and-down sequential technique.Anesthesia was induced by target-controlled infusion of propofol at target plasma concentration of 3.0 μg/ml.Oxycodone was injected at the initial dose of 0.11 mg/kg after the target effect-site and plasma concentrations were balanced.LMA was inserted at 5 min following injection.When the response to LMA insertion was positive,the concentration of oxycodone was increased/decreased in the next patient.The difference between the two successive doses was 0.02 mg/kg.LMA insertion response was defined as occurrence of swallowing,biting on the LMA and bucking and/or body movement during insertion.Probit analysis was used to calculate the ED50 and 95％ confidence interval of oxycodone inhibiting responses to LMA insertion when combined with propofol.Results The ED50 (95％ confidence interval) of oxycodone inhibiting responses to LMA insertion was 0.095 (0.080-0.108) mg/kg when combined with propofol.Conclusion The ED50 of oxycodone inhibiting responses to LMA insertion is 0.095 mg/kg when combined with propofol in the adult female patients.
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Objective To investigate the safety and effectiveness of different intravenous anesthesia methods for pediatric ERCP . Methods Data of 45 children undergoing ERCP at the Affiliated Hangzhou Hospital of Nanjing Medical University from August 2013 to July 2016, including intravenous anesthesia,the procedure of ERCP, adverse reactions and the waking time were retrospectively studied. Results A total of 45 patients in two groups under intravenous anesthesia successfully underwent ERCP . Seventeen patients ( 37. 8%) whose body weights were over 20 kg and the duration of surgery was predicted less than 30 minutes received deep sedation without airway intubation. Twenty?eight patients ( 62. 2%) with an initial weight of less than 20 kg and the duration of surgery was predicted more than 30 minutes received general anesthesia with airway intubation. In patients with deep sedation, the mean time of waking was 7. 2±6. 3 minutes, body movement reaction occurred in 1 case ( 5. 9%) and with transient decreasing of pulse blood oxygen ( beyond 95%) occurred in 2 cases ( 11. 8%) . In patients receiving endotracheal anesthesia with intubation, the mean waking time was 10. 5±8. 7 minutes without adverse reactions associated with anesthesia. Conclusion Both deep sedation and general anesthesia with airway intubation are safe for pediatric ERCP. However, general anesthesia with airway intubation is an ideal method ensuring the airway safety and oxygen supply for children less than 20 kg undergoing first?time ERCP or the duration of surgery lasting over 30 minutes.
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Objective To evaluate the effects of different concentrations of sevoflurane on the cognitive function in neonatal rats.Methods Twenty-four neonatal Sprague-Dawley rats of both sexes,aged 7 days,weighing 12-16g,were randomly divided into high concentration sevoflurane group (group Sev1),low concentration sevoflurane group (group Sev2) or control group (group C),with 8 rats in each group.Sev1 and Sev2 groups were exposed to 2％ and 4％ sevoflurane for 6h,respectively,and C group inhaled gas mixture composed of 30％ oxygen.At 2 and 8 weeks after exposure to sevoflurane,cognitive function was assessed using the open field test and Morris water maze test.Results In the open field test,no significant differences were observed among the three groups (P ＞ 0.05).Morris water-maze test showed that the escape latency was significantly prolonged,and the frequency of crossing the original platform and the time spent in the third quadrant were decreased at 2 weeks after exposure to sevoflurane in Sev1 group and at 2 and 8 weeks after exposure to sevoflurane in Sev2 group as compared with group C (P ＜ 0.05).Morris water-maze test showed that the escape latency was significantly prolonged,and the frequency of crossing the original platform and the time spent in the third quadrant were decreased at 2 and 8 weeks after exposure to sevoflurane in Sev2 group compared with Sev1 group (P ＜ 0.05).Conclusion Exposure to 4％ and 2％ sevoflurane for 6h both can induce cognitive decline and the decreasing effect is enhanced with the increasing concentration in the neonatal rats.
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Poly (hydroxyethyl methacrylate) (PHEMA) hydrogel for intraocular lens (IOL) materials was synthesized by solution polymerization using 2-hydroxyethyl methacrylate (HEMA) as raw material, ammonium persulfate and sodium pyrosulfite (KPS/SMBS) as catalyst, and trietyleneglycole dimethacrylate (TEGDMA) as cross-linking additive. Effects of reaction time, temperature, dosage of catalyst and cross-linking additive on mechanical strength and the equilibrium water content (EWC) of the PHEMA hydrogel were systematically investigated and their structure and optical property were also characterized. The experimental results showed that the optimum conditions for preparing PHEMA hydrogel are: catalyst 0.5 wt%, cross-linking additive 1.0 wt%, reaction temperature 40 degrees C, reaction time 36 h. Under the optimum conditions, the tensile strength of PHEMA hydrogel prepared is as high as 0.57 MPa, hardness of Shore A is 23.0, EWC is over 40%, and light transmittance is over 97%.