Objective To compare the pharmacodynamics of rocuronium intermittently administered according to body surface area and real body weight and individual differences. Method Forty-two patients undergoing elective surgery under general anesthesia were enrolled into the body surface area group (BSA group) and the real body weight group (RBW group), with 21 patients in each group. The patients in the two groups were induced with 2ED95 of rocuronium according to body surface area and real body weight (16.64 mg/m2 in BSA group; 0.6 mg/kg in RBW group). Whenever T1 recovered to 10%, a dosage of 0.5ED95 was administred repeatedly for 30 min before the end of the operation. The time of neuromuscular blockade and recovery of muscle relaxation were recorded, and the dosage of rocuronium was also recorded. Results No significant difference in each index of neuromuscular block time-effect was found between the two groups (P > 0.05). The single dosage and maintainance amount of muscle relaxation were less in the BSA group than that in RBW group (P < 0.05). Compared with the RBW group, the single dosage, dosing intervals, pharmacological duration and the time TOFr recovered to 0.7 between the different individuals were less in the BSA group (P < 0.05). Conclusion The intermittent administration of rocuronium can maintain the same clinical efficacy according to body surface area as that according to real body weight , with significantly less dosageand reducing the differences of individuals in blockade time-effect of muscle relaxation.

Objective To observe the serum concentration of S100βprotein (S100β)and neuron specific enolase (NSE)in patients undergoing supratentorial tumor resection with ulinastatin treat-ment.Methods Twenty-four patients with supratentorial tumor resection,aged 18-65 years,ASA Ⅰor Ⅱ,were randomly divided into the control group (group A,n =12)and ulinastatin group (group U,n =12).Patients in group U received ulinastatin (2 kU/kg)at the beginning of the surgery,with the continuous dose of 1 kU·kg-1 ·h-1 till the end of the operation.Group A received equivalent volume of saline solution as the vehicle control.Blood samples were taken from the artery and jugular venous bulb before induction of anesthesia (T1 ),skin incision (T2 ),1 h after dura openning (T3 ),at the closure of dura (T4 ),at the end of operation (T5 )and 24 h after operation (T6 )to analyze the concentration of S100β and NSE.The concentration of S100β and NSE were determined by ELISA. Results The concentration of serum S100β and NSE increased more significantly higher at T3-T6 in group A than group U (P <0.01).The concentration of serum S100βand NSE in group U were lower than those in group A at T3-T5 (P < 0.01 ).Conclusion Ulinastatin reduces the concentration of serum S100βand NSE during surgery,indicating it alleviates brain injury during supratentorial tumor resection.

OBJECTIVETo investigate the effect of different doses of dexmedetomidine (Dex) on early postoperative cognitive dysfunction in elderly patients undergoing laparoscopic surgery for colorectal cancer.

METHODSEighty ASAI-III elderly patients (over 65 years) were randomized equally into 4 groups including a control group without dexmedetomidine and 3 dexmedetomidine groups (groups D1, D2, and D3) with loading dexmedetomidine doses of 0.2, 0.5, and 0.8 µg/kg and maintenance doses of 0.2, 0.5, and 0.8 µg·kg(-1)·h(-1), respectively. Dex was discontinued 30 min before the end of surgery. The time of operation, adverse reactions, time from the end of surgery to spontaneous breathing recovery (TR), time from spontaneous breathing recovery to opening eyes (TO), and time from opening eyes to extubation (TE) were recorded. Mini-Mental State (MMSE) test was used to assess the cognitive function 1 day before and at 1 day and 3 days after the operation.

RESULTSThe incidence of postoperative cognitive dysfunction (POCD) was significantly lower in groups D2 and D3 than in the control group and group D1 (P<0.05). The incidences of hypotension and bradycardia were the highest in group D3 (P<0.05), which also had longer significantly TO and TE than the other 3 groups (P<0.05).

CONCLUSIONDexmedetomidine with a loading dose of 0.5 µg/kg followed by maintenance doses of 0.5 and 0.8 µg·kg(-1)·h(-1) (preferentially 0.5 µg·kg(-1)·h(-1)) can reduce the incidence of POCD in elderly patients undergoing laparoscopic surgery for colorectal cancer.

Aged ; Cognition ; drug effects ; Colorectal Neoplasms ; surgery ; Dexmedetomidine ; administration & dosage ; Humans ; Laparoscopy ; Postoperative Complications ; Respiration

Objective To investigate the effects of light acute hypervolemic hemodilution on early postop-erative cognitive function in elderly patients. Methods A total of 60 patients treated by radical surgery were equally randomized to an AHH and a non-AHH control group.Using the Mini-Mental State Examination scale (MMSE),we evaluated the cognitive function of the patients.We made comparisons between the two groups in the plasma S100β levels at T0(before anesthesia induction),T1(immediately after hemodilution),T2(immediately after operating),T(36 hour after operating)and T(424 hour after operating).Results The S-100β lever at T2、T3 and T4were markedly higher than T0in both groups(P<0.05);At T3and T4,the S-100β lever was higher in non-AHH control group than AHH group(P<0.05).There was no significant difference in the incidence of postopera-tive cognitive dysfunction between the two groups(P>0.05)There was no significant difference in the incidence of postoperative cognitive dysfunction between the two groups(P > 0.05). Conclusions AHH can significantly reduce plasma S100β in elderly patients,but there is no effect on early postoperative cognitive function.

Objective To investigate whether the median(50%)effective effect-concentration(EC50)of propofol inducing loss of consciousness (LOC) varies. Methods 56 patients undergoing gastroscopy under general anaesthesia were enrolled on the study. Anaesthesia was conducted with a target-controlled infusion(TCI) of propofol. The initial target effect-site propofol concentration (Ceprop) was 5.00 μg/mL and was adjusted stepwise by 0.50μg/mL by an up-down sequential method to reach no-movement. Results Propofol EC50 to induce no-movement was higher in patients with anxiety than those without anxiety(6.46μg/mL vs. 5.75μg/mL,P<0.05). Conclusions During general anaesthesia ,patients with anxiety had a higher propofol EC50 for no-movement compared with those without anxiety. Differences in preoperative anxiety levels may reduce anaesthetic effects.

Objective To investigate the effect of preoperative anxiety on propofol EC50 for nomovement during Painless gastroscopy.Methods Thirty-one patients (without anxiety) and twenty-seven patients (with anxiety) undergoing gastroscopy under general anesthesia were enrolled on the study.Anesthesia was conducted with a target-controlled infusion (TCI) of propofol.The initial target effect-site propo fol concentration (Ceprop) was 5.0 μg/ml and was adjusted stepwise by 0.5 μg/ml by an up-down sequential method to reach no-movement.Results Propofol EC50 to induce no-movement was higher in patients with anxiety than those without anxiety (5.32 μg/ml,95％ CI:4.75-5.88 μg/ml vs 4.75 μg/ml,95％ CI:4.48-5.01 μg/ml,P ＜ 0.05).Conclusions During painless gastroscopy,patients with anxiety had a higher propofol EC50 for no-movement compared with those without anxiety when intravenous injected of fentanyl 0.1 μg/kg.