Objective: To evaluate the feasibility and advantages or disadvantages of patient-controlled sedation (PCS) compared with doctor-controlled sedation (DCS) during epidural anesthesia. Method: Forty patients were divided at random into two groups with 20 patients in each group. Patients in group I were administered by themselves a mixture of propofol (20mg) and fentanyl (10?g) in increments using a Graseby PCA infuser (lockout period 1 min) to achieve sedation; patients in group Ⅱ received propofol 3.6mg?kg~(-1)?h~(-1) and fentanyl 1.8?g~(-1)?kg~(-1)?h~(-1)contin uously intravenously by the anesthesiologist to achieve intra-operative sedation. Sedation scale, satisfaction and cooperation degrees were measured. Cognition was also evaluated using abbreviated Mini Mental Status Examination. Result: The drug total dose used in DCS group was higher than that in group PCS (P

0 35 The patients had no endocrine or immune disease and received neither radio , chemo nor hormone therapy Anesthesia was induced with propofol, midazolam, fentanyl and succinylcholine After tracheal intubation the patients were mechanically ventilated Anesthesia was maintained with enflurane inhalation and intermittent intravenous boluses of midazolam, fentanyl and vecuronium After operation the patients were transferred to recovery room and PCA was started when the patients were wide awake VAS was maintained at 2 4 Venous blood samples were taken before surgery, before blood transfusion and on the 1st and 5th postoperative day for determination of T lymphocyte subsets and natural kill cell counts by flow cytometry (EPICS Elite USA) Results The two groups were comparable regard to sex, types of operation, intraoperative blood loss and volume of fluid infused The mean duration of operation of the two groups was (196?42) min The NK cell and CD + 3 and CD + 4 counts and CD + 4/CD + 8 ratio before transfusion were not significantly different from those before operation in both groups The NK cell, CD + 3 and CD + 4 counts and CD + 4/CD + 8 ratio decreased significantly on the 1st postoperative day in both groups but the decrease was more pronounced in group H On the 5th postoperative day the NK cell, CD + 3, CD + 4 counts and CD + 4/CD + 8 ratio returned to preoperative level in group A but remained low in group H Couclusions Perioperative homologous blood transfusion has serious and prolonged inhibitory effects on patient′s immune function In autologous blood transfusion group the changes are milder and the recovery is more rapid as compared with those in group H

BACKGROUND:It has been clinically confirmed that inhalation of hyperoxic oxygen for 36-48 hours can causes irreversible hyperoxic lung injury.Whether inhaling oxygen less than 50％ can reduce the potential oxygen toxicity in lung injury? OBJECTIVE:To observe the changes of lung ultrastructures after pure xygen inhalation for 7 hours through endotracheal intubation in dogs. DESIGN:A randomized and controlled animal experiment. SETTING:Department of Anesthesiology,Affiliated Hospital of Medical College,Qingdao University.MATERIALS:Totally 20 healthy hybrid dogs (6 females and 14 males),weighing 15-16 kg,were provided by the Animal Experimental Center in the Affiliated Hospital of Medical College,Qingdao University.BIRD 8400STi respiratory machine (Bird,USA) and HP-M102A multi-functional monitor (HP,USA) were used.METHODS:The experiment was completed in the Experimental Animal Center in the Affiliated Hospital of Medical College,Qingdao University from July 1999 to January 2000.① Interventions:The dogs were randomly ventilated with either fraction of inspired oxygen (FiO2) of 1 (group 1,n =10) or FiO2 of 0.34 (group 2,n =10),there were 3 females and 7 males in each group.All the dogs were ventilated for 7 hours.② Evaluation:The mean arterial pressure and heart rate were monitored at 1,3,5 and 7 hours after endotracheal intubation.Anesthetic gas monitor (Ohmeda 5250 RGM) was used to observe the fractional inspired oxygen concentration,end-tidal partial pressure of carbon dioxide (PetCO2), respiratory frequency and peaks of respiratory organs.Changes of lung ultrastructures of right lower lung lobe were observed with electron microscopy after 7-hour mechanical ventilation.MAIN OUTCOME MEASURES:① Hemodynamic parameters; ② Changes of lung ultrastructures. RESULTS:All the 20 dogs were involved in the anlaysis of analysis.① Results of hemodynamic parameters:There was no significant difference between the two groups at each time point mean arterial pressure,PetCO2,peaks of respiratory organs and heart rate (P ＞ 0.05).② Changes of lung ultrastructures:The results of electron microscope showed that in group 1,there were swelling mitochondria was arranged in disorder,less matrix,and hyalomere appeared,thin double-deck membrane in 50％ samples; Interalveolar septum stroma was with edema in 60％ samples;Polymorphonuclear leukocyte gathered in vessel or emigrated out of vessel in 50％ samples; In group 2,double-deck membranes of mitochondria were integral,densely matrix showed micro-granule shape in 90％ samples; Pinocytosis in epithelial cells of type Ⅰ lung strengthened,being destroyed,and pinocytosis in endothelial cells strengthened in 10％ samples; Interalveolar septum stroma was with edema,no polymorphonuclear leukocyte gathered in vessel or emigrated out of vessel or corpuscule was empty in type Ⅱ alveolar epithelium in 20％ samples.CONCLUSION:More pathological ultramicroscopic changes are observed after 7-hour mechanical ventilation with pure oxygen,which reduces after mechanical ventilation with 34％ oxygen.Oxygen concentration should be decreased while long-time mechanical ventilation is executed so as to reduce potential lung injury with oxygen toxicity.

BACKGROUND:Autologous shed blood washing with the autologous transfusion system involving recovery, anticoagulation, centrifugation, concentrating and washing has been widely used in clinical practice.
OBJECTIVE:To clarify the characteristics of erythrocytes washing with autologous transfusion system, including recovery rate and hematocrit, the changes of shape, deformability, flow properties and in vivo half-life, oxygen carrying and delivering capacity and erythrocyte immunity and immunereceptor expression.
METHODS:The literatures published from January 1987 to January 2013 were retrieved by the first author in Wanfang and PubMed databases. Key words were“blood transfusion, autologus, blood preservation, erythrocytes”in English and Chinese. A total of 200 literatures relating to the erythrocyte characteristics in autologous blood transfusion were found by the computer, 60 of which were retained for further analysis after eliminating repetitive researches.
RESULTS AND CONCLUSION:Because of the mechanical force, such as negative pressure suction, centrifugal separation, and inflammatory mediators, enzymes, activated complements released by various damaged tissues and cells, the col ected erythrocytes were damaged to some extent. As a result, the total recovery rate of erythrocytes depended on the recovery rate, storage breakage rate and cleaning loss rate. The oxygen carrying capacity of erythrocytes was not influenced significantly by this procedure, so the recycled erythrocytes had the same oxygen carrying capacity with normal erythrocytes. To some extent, the number of surface receptors and immune function of recycled erythrocytes descended, but they were better than the erythrocytes preserved for 2 weeks. Studies suggested that blood recovery technology should be improved to reduce the functional decline in immune adherence of the recycled erythrocytes.

Objective To establish a neuropathic pain model by transection of L4 spinal nerve in rats.Methods Twenty-eight male SD rats weighing 270-310 g were randomly divided into 3 groups: A experimental group (n = 12) received transection of right L4 spinal nerve; B sham operation group ( n = 8) in which right L4 spinal nerve was exposed but not transected and C control group ( n = 8) received no surgery. The paw withdrawal threshold (PWT) to mechanical stimulation was measured by using modified von Frey test. The response to cold stimulation evoked by applying acetone to the plantar region of hindpaw was measured and scored. The threshold to both noxious mechanical and thermal stimuli was measured once a week for 8 weeks. Results In experimental group the pain threshold to mechanical stimuli (von Frey hair stimulation) and cold stimuli (acetone test) on the operated side were significantly decreased after L4 spinal nerve transection as compared to the baseline values before operation and significantly lower than in sham operation and control groups. There was no significant change in the withdrawal response of the hindpaw to mechanical and cold stimuli after surgery on the unoperated side. Conclusion Hyperalgesia to mechanical and cold stimuli develops after L4 spinal nerve transection on the operated side and lasts more than 8 weeks

Objective To investigate the effect of nicorandil pretreatment on myocardial mitochondria in a rabbit model of myocardial ischemia-reperfusion (I/R). Methods Tirty-two healthy male New Zealand white rabbits weighing 2.0-2.5 kg aged 4 months were randomly allocated into 4 groups ( n = 8 each): Ⅰ group sham operation (group S); Ⅱ group I/R; Ⅲ group nicorandil pretreatment (group N) and Ⅳ group nicorandil + 5 hydroxydecanoic acid (group N + 5-HD). Myocardial I/R was induced by 30 min occlusion of left circumflex coronary artery followed by 120 min reperfusion. In group N and N + 5-HD a bolus of nicorandil 100 μg/kg was given iv at 10 min before myocardial ischemia followed by continuous infusion at 10 μg· kg-1 · min-1 until the beginning of myocardial ischemia. In group Ⅳ a bolus of 5-HD 5 mg/kg was injected iv at 20 min before myocardial ischemia.The animals were sacrificed at the end of 120 min reperfusion. The mitochondrial membrane potential was measured by flow cytometry using JC-1 fluorescence probe as indicator. Bcl-2, Bax and cytochrome c protein expression was determined by immuno-histochemistry. Myocardial ultrastructure was examined with transmission electron microscope. Results Red fluovescence intensity indicating normal live cells was significantly higher, the green fluorescence intensity indicating apoptotic cells was lower and red/green fluorescence intensity ratio was higher; the Bcl-2/Bax ratio was significantly higher and cytochrome c protein expression lower in group N than in group I/R.5-HD administration negated the protective effect of nicorandil pretreatment against myocardial I/R injury. Conclusion Nicorandil stabilizes mitochondrial membrane potential, decreases cytochrome c protein releasing, and suppresses mitochondrial apoptotic signal transduction by opening the mito-KATP channels.

Objective To investigate the effect of dexmedetomidine on minimum alveolar concentration (MAC) of isoflurane required to inhibit the body movement during skin incision. Methods Forty-eight ASA Ⅰ or Ⅱ patients aged 40-60 yr with body mass index of 22-27 kg/m2 undergoing elective upper abdominal surgery under general anesthesia were randomly divided into 3 groups: control group (group C, n = 15);low dose dexmedetomidine group (group D1, n = 17) and high dose dexmedetomidine group (group D2, n = 16). The patients were unpremedicated. Dexmedetomidine 0.4 and 0.8 μg/kg in normal saline (NS) 15 ml was infused over 15 min before induction of anesthesia in D1 and D2 groups respectively. Anesthesia was induced with fentanyl-propofol-succinylcholine. The patients were mechanically ventilated after tracheal intubation. Anesthesia was maintained with isoflurane. MAC of isoflurane was determined by up-and-down technique. The initial end-tidal isofiurane concentration was set at 1.0%, 0.8% and 0.6% in C, D1 and D2 groups respectively. Each time the end-tidal isoflurane concentration was increased/decreased by 0.2%. Skin incision was made after 15 min of equilibration, when the twitch height returned to more than 90% of its control value. Movement of body and limbs including swallowing and coughing were carefully looked for when skin incision was made. MAC of isoflurane was the mean of end-tidal concentration of isoflurane of each crossover pair, and 95 % CI was calculated. Results MAC of isoflurane was significantly decreased in D1 and D2 groups as compared with group C and in group D2 as compared with group D1( P ＜ 0.05 or 0.01 ). Conclusion Dexmedetomidine can significantly decrease MAC of isoflurane required to inhibit the body movement during skin incision in a dose-dependent manner.

Objective To investigate the effect of dexmedetomidine on median effective target effect-site concentration ( EC50) of sufentanil inhibiting body movement evoked by skin incision in patients undergoing bilateral subtotal thyroidectomy. Methods Thirty-nine ASA I or II patients of both sexes aged 20-64 yr with a body mass index of 20-25 kg/m2 undergoing bilateral subtotal thyroidectomy were randomly divided into 2 groups: control group (group C) and dexmedetomidine group (group D). The patients were premedicated with intramuscular phenobarbital 0.1 g and scopolamine 0.3 mg. In group D dexmedetomidine 0.6 μg/kg was injected iv over 10 min at S min before induction of anesthesia. Anesthesia was induced with target-controlled infusion (TCI) of propofol and sufentanil. The target plasma concentration of propofol was set at 3.0 μg/ml which was maintained until the end of operation. TCI of sufentanil was started at 10 min after initiation of propofol TCI. The initial target effect-site concentration was set at 0.20 ng/ml and decreased/increased by 20% in the next patient according to whether the patient's body moved or not within 1 min after skin incision. Laryngeal mask airway was inserted at 3 min after initiation of sufentanil TCI. Spontaneous breathing was maintained. Skin incision was made at 10 min after initiation of sufentanil TCI. The EC50 and 95% confidence interval (CI) of sufentanil inhibiting skin incision-evoked body movement were calculated with sequential method. Results EC50, of sufentanil was 0.1148 ng/ml (95% CI 0.1055-0.1249 ng/ml) in group D and 0.1454 ng/ml (95% CI 0.1339-0.1580 ng/ml) in group C, and was significantly lower in group D than in group C. Conclusion Dexmedetomidine 0.6 μg/kg infused iv before operation can reduce the EC50 of sufentanil inhibiting body movement evoked by skin incision in patients undergoing bilateral subtotal thyroidectomy.

Objective To compare the effects of dexmedetomidine and fentanyl on the median effective concentration (EC50) of propofol required for inducing respiratory depression.Methods ASA physical status Ⅰ or Ⅱ patients,aged 30-50 yr,weighing 50-75 kg,with body mass index of 22-28 kg/m2,scheduled for elective gynecological surgery under general anesthesia,were randomly divided into 3 groups:control group (group C),dexmedetomidine group (group D) and fentanyl group (group F).Dexmedetomidine 0.5 μg/kg and fentanyl 1.5 μg/kg in 10ml of normal saline were infused over 10 min in D and F groups,respectively,while the equal volume of normal saline was given in group C.Lidocaine was injected intravenously followed by target-controlled infusion of propofol.In C,D and F groups,the initial target concentration of propofol was 2.5,2.1 and 1.1 μg/ml,respectively,and the ratio between the two successive concentration gradients was 1.1.It was defined as positive when patients developed respiration depression.EC50 and 95％ confidence interval of propofol inducing respiratory depression were calculated.BIS values and OAA/S scores were recorded after admission to operating room (T0),after infusion of dexmedetomidine,fentanyl or normal saline,at 5 and 10 min after the start of propofol target-controlled infusion and after the target effect-site and plasma concentrations were balanced.Results EC50 (95％ confidence interval) of propofol required for inducing respiratory depression was 2.72 (2.55-2.91),2.15 (2.05-2.27)and 1.17(1.08-1.25) μg/ml in C,D and F groups,respectively.Compared with group C,the EC50 was significantly decreased in D and F groups and the BIS values and OAA/S scores were increased in group F (P ＜ 0.05),and no significant changes were found in the BIS values and OAA/S scores in group D (P ＞ 0.05).The EC50 was significantly decreased and the BIS values and OAA/S scores was increased in group F as compared with group D (P ＜ 0.05).When the BIS values reached 65 or OAA/S scores was 3,the effect-site concentration was significantly lower in D and F groups than in group C (P ＜ 0.05).In C,D and F groups,the percentage of patients who developed upper airway obstruction caused by glossocoma was 100％,60％ and 20％,respectively,and who developed decreased respiratory rate or apnea (RR≤ 8 bpm or respiratory arrest time≥ 15 s) was 0,40％ and 80％,respectively.Conclusion Although dexmedetomidine induces no respiratory depression,dexmedetomidine can enhance the potency of propofol required for inducing respiratory depression and the prtency is lower than that of small-dose fentanyl.

BACKGROUND:Transfusion guidelines pointed out:whole blood should be stored at (4±2)℃. The bacterial growth or loss of function should occur if the blood leaves the suitable storage conditions. Recipients wil suffer from different degrees of blood transfusion reaction or invalid infusion.
OBJECTIVE:To observe morphology of erythrocytes of autologous blood stored at different temperatures using microscope.
METHODS:Blood was obtained from 40 cases of acute normovolemic hemodilution and stored in ACD citrate bags. Whole blood was respectively stored at 4 ℃ and 23 ℃. Blood smear was taken respectively in the blood storage immediately, 1, 2, 3, 4, 5 and 6 hours after col ecting autologous blood. Changes in morphology of erythrocytes were observed with a microscope. Deformity rate of erythrocytes was calculated. Six blood samples were randomly selected to test pH, K+, and free hemoglobin respectively in 6-hour common temperature group and ACD banked blood within the valid period. Six blood samples were randomly selected for the bacterial culture in each group of two groups at 6 hours.
RESULTS AND CONCLUSION:There were no significant differences in abnormality rates of erythrocytes between 4 ℃ and common temperature groups at each time point. The pH, K+, free hemoglobin at six hours in the common temperature group were better than those of ACD banked blood within the valid period and there was no bacterial growth in culture between the two groups. Therefore, it is feasible to transfuse autologous blood back to the patient within 6 hours of storage at room temperature.