Objective To evaluate the protective effects of different modes of ventilation on the lungs on the operated side during one-lung ventilation (OLV ) in patients undergoing thoracic surgery .Methods Forty-five ASA physical status Ⅰ or Ⅱ patients of both sexes ,aged 45-64 yr ,weighing 65-80 kg ,were randomly divided into 3 groups (n=15 each) using a random number table :group A ,group B and group C .After induction of anesthesia ,the patients were intubated with double-lumen tube and OLV was performed .During OLV ,the lung on the operated side was collapsed naturally in group A ,positive pressure ventilation (FGF 2 L/min) was applied in the lung on the operated side in group B ,and high-frequency jet ventilation (frequency 100 beats/min ,driving pressure 0.5 kg/cm2 ) was used in the lung on the operated side in group C .Immediately after intubation (T0 ) , and at 1.5 h (T1 ) and 2 h (T2 ) of OLV ,blood samples were taken from the central vein and radial artery for determination of the serum interleukin-6 (IL-6 ) and IL-8 concentrations .The net release of IL-6 and IL-8 was calculated .Blood samples were taken from the radial artery at T0-2 for blood gas analysis and for determination of surfactant protein A (SP-A) concentration in the serum .Respiratory index (RI) was calculated .The non-cancer tissues 1.0 cm × 1.0 cm × 1.0 cm which were extracted from the lung cancer specimens were used for microscopic examination of the pathological changes of lungs which were scored .Results Compared with group A ,the net release of IL-6 and IL-8 ,serum SP-A concentration ,RI and pathological scores were significantly decreased at T1 ,2 in B and C groups ( P<0.05) .Compared with group B ,the serum SP-A concentration and RI were significantly decreased at T1 ,2 , and the net release of IL-6 was increased at T2 in group C ( P< 0.05 ) .Conclusion Continuous positive ventilation and high-frequency jet ventilation both can effectively protect the lungs on the operated side during OLV in patients undergoing thoracic surgery ,and the efficacy of high-frequency jet ventilation is better .

Objective To evaluate the correlation between stroke volume variation (SVV) and blood volume during one-lung ventilation (OLV).Methods Forty ASA Ⅱ male patients,aged 50-60 yr,with body mass index 20-25 kg/m2,scheduled for elective resection of esophageal cancer,were studied.Anesthesia was induced with fentanyl 4 μg/kg,propofol 2 mg/kg,and rocuronium 0.6 mg/kg.Double-lumen tube was inserted.Correct position was verified by fiberoptic bronchoscopy.The patients were mechanically ventilated (VT 8 ml/kg,RR 15 bpm,Ⅰ ∶ E 1 ∶ 2).6％ hydroxyethyl statch (HES) 130/0.4 was infused intravenously at a rate of 0.67 ml· kg-1 · min-1 starting from 30 min of OLV.SVV,cardiac output (CO),SV and cardiac index (CI) were monitored and recorded using the FloTrac/Vigileo (Edwards Lifesciences,USA) system before HES was infused and when the dose of HES reached 2,4,6,8,10 and 12 ml/kg.Spearman rank sum correlation coefficient was used to analyze the data.Results SVV was negatively correlated with the blood volume during OLV and the correlation coefficient was rSVV =-0.249.CI,CO and SV were positively correlated with the blood volume during OLV and the correlation coefficients were rCO =0.570,rSV =0.552 and rCI =0.550,respectively.Conclusion SVV is poorly correlated with the blood volume during OLV and can not reflect the blood volume accurately.

Objective To evaluate the correlation between stroke volume variation (SVV) and the blood volume. Methods Forty-eight ASA Ⅱ male patients, aged 50-60 yr, scheduled for elective radical operation for gastric cancer, were studied. Anesthesia was induced with fentanyl 4 μg/kg, propofol 2 mg/kg and cis-atracurium 0.15 mg/kg and maintained with inhalation of 2%-3% sevoflurane. 6% HES 130/0.4 was infused intravenously at a rate of 0.67 ml· kg - 1 · min - 1 30 min after induction. SVV,cardiac output (CO),SV and cardiac index (CI) were monitored and recorded using the FloTrac/Vigileo (Edwards Lifesciences, USA) system before HES was infused and when the dose of HES reached 2, 4, 6, 8, 10, 12, 14, 16 and 18 ml/kg. CVP was also recorded at the corresponding time points. Spearman's rank sum correlation coefficient was used to analyze the data. Results Correlation coefficients between the amount of HES infused and CO, SV, CI or CVP were rSVV = - 0.91 ± 0.06,rCO = 0.83 ± 0.04, rSV = 0.86 ± 0.09, rCI = 0.86 ± 0.09 and rCVP = 0.90 ± 0.03. Among the 5 correlation coefficients, rSVV was the highest, rCVP was significantly higher than rCO, rSV and rCI (P ＜ 0.05), and there was no significant difference among rCO, rSV and r CI (P ＞ 0. 05). Conclusion SVV is highly correlated with the blood volume and can be used to guide volume therapy.

Objective To compare the cost-effectiveness of closed-loop versus open-loop infusion of propofol guided by bispectral index (BIS) in elderly patients undergoing abdominal surgery.Methods Sixty American Society of Anesthesiologists physical status Ⅱ patients of either sex,aged 65-75 yr,with body mass index of 18 25 kg/m2,undergoing elective open gastrointestinal tumor resection with general anesthesia,were allocated into closed-loop target-controlled infusion (TCI) group (group C) and open-loop TCI group (group O) using a random number table.Propofol was given using closed-loop TCI,and the target BIS value was set at 45-55 in group C.In group O,the target plasma concentration (2.0-3.5 μg/ml)of propofol was adjusted to maintain the BIS value at 45-55.Remifentanil was given by TCI with the target plasma concentration of 2-8 ng/ml in both groups.The total consumption of propofol and remifentanil,time rate of maintaining BIS value within the target range,development of intraoperative hypertension and hypotension,emergence time,tracheal extubation time,time for recovery of orientation,first ambulation time,time to first flatus and length of postoperative hospital stay were recorded.The development of nausea and vomiting and delirium within 3 days after operation and intraoperative awareness was recorded.The cost of anesthetics and total cost of anesthesia were calculated.Results Compared with group O,the total consumption of propofol was significantly decreased,the total consumption of remifentanil was increased,the time rate of maintaining BIS value within the target range was increased,the emergence time,tracheal extubation time and time for recovery of orientation were shortened,the cost of propofol and total cost of anesthesia were decreased (P＜0.05),and no significant change was found in the cost of remifentanil,incidence of postoperative delirium and nausea and vomiting,first ambulation time,time to first flatus or length of postoperative hospital stay in group C (P＞0.05).Intraoperative awareness was not found in two groups.Conclusion Compared with open-loop infusion of propofol guided by BIS,closed-loop infusion of propofol guided by BIS is a cost-effective method of anesthesia in elderly patients undergoing abdominal surgery.

Objective To evaluate the effects of different doses of dexmedetomidine on stress responses of the hypertensive patients undergoing thoracic surgery and find the uptimal infusion rate of dexmedetomidine in decreasing stress responses.Methods Sixty hypertensive patients of both sexes,aged 45-64 yr,weighing 65-80 kg,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,were divided into 4 groups (n =15 each) using a random number table:control group (group C) and 3 different doses of dexmedetomidine groups (D1-3 groups).In D1,D2 and D3 groups,dexmedetomidine 0.2,0.3 and 0.4 μg · kg 1 · h 1 were intravenously infused until 30 min before the end of surgery,respectively,starting from 15 min before induction of anesthesia.The equal volume of normal saline was given instead of dexmedetomidine in group C.Before administration of dexmedetomidine (T0),at 1 min after endotracheal intubation (T1),at skin incision (T2) and immediately after extubation (T3),venous blood samples were collected for determination of epinephrine and norepinephrine concentrations in plasma (using high-performance liquid chronatography) and blood glucose concentrations.The development of adverse effects such as bradycardia,hypotension and respiratory depression was recorded.Results Compared with group C,epinephrine and norepinephrine concentrations in plasma and blood glucose concentrations were significantly decreased at T1-3 in D1,D2 and D3 groups,the incidence of bradycardia and hypotension was significantly increased in group D3 (P＜0.05),and no significant change was found in the incidence of bradycardia or hypotension in D1 and D2 groups (P＞0.05).There were no significant differences in epinephrine and norepinephrine and concentrations in plasma and blood glucose concentrations at each time point between group D1,group D2 and group D3 (P ＞ 0.05).Conclusion The optimal infusion rates of dexmedetoinidine are 0.2 and 0.3μg · kg-1 · h-1 in decreasing stress responses of the hypertensive patients undergoing thoracic surgery.

Objective To determine the optimal dose of oxycodone for patient-controlled intravenous analgesia (PCIA) after gastrointestinal surgery when combined with dexmedetomidine in elderly patients.Methods Sixty patients of both sexes,aged 65-80 yr,weighing 50-75 kg,of American Society of Anesthesiologists physical status Ⅱ or Ⅲ,undergoing elective open gastrointestinal surgery,were divided into 3 different doses of oxycodone groups (group O1,group O2 and group O3,n=20 each) using a random number table.At 15 min before the end of surgery,oxycodone 0.1 mg/kg was intravenously injected,and PCIA pump was connected simultaneously.In O1,O2 and O3 groups,the PCIA solution contained dexmedetomidine 2.0 μg/kg and oxycodone 0.3,0.5 and 0.7 mg/kg in 100 ml of 0.9％ normal saline,respectively.The PCIA pump was set up to deliver a 0.5 ml bolus dose with a 15-min lockout interval and background infusion at 2 ml/h.Oxycodone 0.05 mg/kg was intravenously injected as a rescue analgesic after surgery,postoperative pain was assessed using a verbal rating scale,and the verbal rating scale score was maintained ≤4.The number of successfully delivered doses and requirement for rescue analgesics were recorded within 48 h after surgery,and the rate of rescue analgesia was calculated.The occurrence of adverse reactions such as nausea,vomiting,dizziness,respiratory depression,somnolence,bradycardia,hypotension and over-sedation was recorded.Patients' satisfaction with analgesia at postoperative 72 h and the length of postoperative hospital stay were also recorded.Results Compared with group O1,the rate of rescue analgesia after surgery and the number of successfully delivered doses were significantly decreased,and the degree of patients' satisfaction with analgesia was increased in O2 and O3 groups,and the incidence of nausea and somnolence was significantly increased in group O3 (P＜0.05).Compared with group O2,no significant change was found in the rate of rescue analgesia after surgery or the number of successfully delivered doses (P＞0.05),and the incidence of nausea and somnolence was increased in group O3 (P＜0.05).Conclusion When combined with dexmedetomidine 2.0 μg/kg,the optimal dose of oxycodone for PCIA is 0.5 mg/kg after gastrointestinal surgery in elderly patients.

Objective To investigate the optimum ratio of medicine dosage for dexmedetomidine mixed with oxycodone used for patient-controlled intravenous analgesia (PCIA) after gastrointestinal surgery.Methods Eighty patients of both sexes, aged 35-64 yr, weighing 55-75 kg, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ , undergoing elective gastrointestinal surgery, were randomly divided into 4 groups (n=20 each) using a random number table: oxycodone group (group O), and different ratios of medicine dosage when dexmedetomidine was added to sufentanil groups (OD1-3 groups).At 15 min before the end of surgery, oxycodone 0.1 mg/kg was injected intravenously, and PCIA pump was connected simultaneously.In group O, the PCIA solution contained oxycodone 1.00 mg/kg in 100 ml of normal saline.In group OD1, the PCIA solution contained oxycodone 1.00 mg/kg and dexmedetomidine 2.5 μg/kg in 100 ml of normal saline.In group OD2 , the PCIA solution contained oxycodone 0.75 mg/kg and dexmedetomidine 2.5 μg/kg in 100 ml of normal saline.In group OD3, the PCIA solution contained oxycodone 0.50 mg/kg and dexmedetomidine 2.5 μg/kg in 100 ml of normal saline.The PCIA pump was set up to deliver a 0.5 ml bolus dose with a 15-min lockout interval and background infusion at 2 ml/h.Oxycodone 0.05 mg/kg was injected intravenously as a rescue analgesic, and visual analogue scale score was maintained ≤ 4.The requirement for rescue analgesics was recorded.The requirement for the rescue analgesic was recorded within 48 h after surgery.The number of successfully delivered doses, and occurrence of adverse reactions such as bradyeardia, hypotension, nausea, vomiting, over-sedation, somnolence, pruritus, and respiratory depression were recorded.Patient's satisfaction with analgesia was recorded at 72 h after surgery.Results No patients required the rescue analgesic or developed over-sedation, vomiting, respiratory depression and hypotension in the four groups.Compared with group O, the incidence of somnolence was significantly increased in group OD1, the incidence of nausea, somnolence, bradycardia and pruritus was decreased in OD2 and OD3 groups, and the degree of patient's satisfaction with analgesia was increased in OD1-3 groups (P＜0.05).Compared with group OD1, the incidence of nausea, somnolence, bradycardia and pruritus was significantly decreased in OD2 and OD3 groups, the degree of patient's satisfaction with analgesia was increased in group OD3 (P＜0.05) , and no significant was found in the degree of patient's satisfaction with analgesia in group OD2 (P＞0.05).Compared with group OD2, no significant was found in the incidence of adverse reactions (P＞0.05) , and the degree of patient's satisfaction with analgesia was significantly decreased in group OD3 (P＜0.05).The number of successfully delivered doses was significantly larger in group OD3 than in O, OD1 and OD2 groups (P＜0.05).Conclusion Dexmedetomidine 2.5 μg/kg added to oxycodone 0.75 mg/kg is the optimum ratio of medicine dosage when used for PCIA after gastrointestinal surgery.

Objective To evaluate the effect of neoadjuvant chemotherapy for ovarian cancer on the sedative potency of propofol and oxycodone for anesthesia induction.Methods Sixty-eight American Society of Anesthesiologists physical status Ⅰ or Ⅱ patients,aged 40-64 yr,with body mass index of 20-30 kg/m2,scheduled for elective radical resection of ovarian cancer with general anesthesia,were divided into into 2 groups (n =34 each) according to whether the patients received neoadjuvant chemotherapy before surgery:neoadjuvant chemotherapy group (group Ⅰ) and non-chemotherapy group (group Ⅱ).Patients received 3 cycles of chemotherapy (21 days for 1 cycle),chemotherapy regimen was paclitaxel and carboplatin,and patients underwent surgery after 3 weeks of chemotherapy in group Ⅰ.Anesthesia was induced with Ⅳ oxycodone 0.2 mg/kg.Propofol was given by target-controlled infusion 4 min later,and the effectsite concentration (Ce) of propofol was determined by up-and-down technique,with the initial Ce 1.0 μg/ml and the ratio between the two successive Ces 1.09.The median-effective target plasma concentration (EC50) and 95％ confidence interval of propofol causing loss of consciousness were calculated using Probit analysis.Results The EC50 and 95％ confidence interval of propofol causing loss of consciousness were 1.22 μg/ml (1.14-1.30 μg/ml) and 1.74 μg/ml (1.57-3.19 μg/ml) in group Ⅰ and group Ⅱ,respectively.Compared with group Ⅱ,the EC50 of propofol causing loss of consciousness was significantly decreased in group Ⅰ (P＜0.05).Conclusion Neoadjuvant chemotherapy for ovarian cancer can enhance the sedative potency of propofol and oxycodone for anesthesia induction.

Objective:To evaluate the accuracy of surgical pleth index (SPI) in monitoring the depth of anesthesia in elderly patients undergoing general anesthesia.Methods:Thirty-five patients, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, aged 65-80 yr, with body mass index of 18-30 kg/m 2, scheduled for elective gynecological laparoscopic surgery, were studied.Combined intravenous-inhalational anesthesia was used to maintain bispectral index value at 45-60.SPI was recorded within 2 min before and after skin incision, before and after pneumoperitoneum, and before and after the most intense stimulation of skin incision.The maximum value (SPI max) within 2 min after noxious stimulation was recorded, and the difference between SPI max and baseline value (ΔSPI) was calculated.The receiver operating characteristic curve (ROC) was used to evaluate the accuracy of the above indicators in monitoring the depth of anesthesia. Results:Thirty patients were finally included in this study.The area under the curve of SPI max was 0.887, the diagnostic threshold was 57, the sensitivity was 68.9%, and the specificity was 92.9%.The area under the curve of ΔSPI was 0.988, diagnostic threshold was 12, the sensitivity was 88.0%, and the specificity was 98.7%. Conclusion:SPI can accurately determine the depth of anesthesia in elderly patients with general anesthesia, and using ΔSPI has more clinical significance.

Objective: To understand cumulative health risk behaviors among college students and the association with adverse childhood experiences, so as to provide a theoretical basis for the prevention and control of health risk behaviors in this population. Methods: From November to December 2022, four universities in Shanghai were selected using convenience sampling, and 3 039 students were selected for a questionnaire survey using random cluster sampling. The questionnaire covered general basic information, adverse childhood experiences and health risk behaviors. A latent class analysis was carried out to explore the latent classes of health risk behaviors among the college students and multivariate Logistic regression was performed to analyze the association between adverse childhood experiences and cumulative health risk behaviors. Results: The health risk behaviors of college students were classified into three latent classes:a low risk group (84.60%), a high risk group for smoking and alcohol consumption ( 10.37 %), and an excessive sugar intake group (5.03%). The proportion of three latent classes of health risk behaviors varied significantly by childhood neglect and abuse, family functioning and other adverse childhood experiences ( χ 2=210.67, 106.55, 104.41 , P <0.01). The results of the multiple Logistic regression analysis revealed that childhood neglect and abuse, poor family functioning, and other adversities increased the risk in the high risk group for smoking and alcohol consumption among college students ( OR =6.24, 3.80, 3.68), as well as an childhood neglect and abuse increased the risk of the excessive sugar intake group among college students ( OR =2.18) ( P <0.01). Conclusions Adverse childhood experiences are associated with clustered health risk behaviors. Proactive measures should be taken to prevent the transmission of negative childhood experiences, which would contribute to reduce the occurrence of health risk behaviors among college students.