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Objective To investigate the sensitivity of adult worms of filial generations from praziquantel-resistant and -sensitive Schistosoma japonicum mixed infections to praziquantel. Methods Mice were infected with the cercariae of an experimentally generated praziquantel-resistant S. japonicum isolate [median effective dose (ED50) = 277.4 mg/kg] and a laboratory-maintained praziquantel-sensitive S. japonicum isolate (ED50 = 99.6 mg/kg) at a mixture ratio of 1:1 and 2:1, which was maintained in the laboratory via the mouse-snail cycle for 8 generations. Then, mice were infected with the cercariae of the 8th filial-generation parasite, and grouped 35 days post-infection. Mice in the 5 treatment groups were given praziquantel treatment by gavage at a single oral dose of 37.5, 75, 150, 300 mg/kg and 600 mg/kg, while animals in the control group was administered orally with 2.5% cremophor EL. All mice were sacrificed 14 days post-treatment and adult worms were collected by perfusion of the portal vein. The worm burden reductions and praziquantel ED50 values were calculated. The praziquantel-resistant S. japonicum isolate generated from experimental induction with 12 rounds of praziquantel treatment with sub-curative doses was maintained in the laboratory via the mouse-snail cycle, and mice were infected with the cercariae of the 8th filial-generation parasite. The praziquantel ED50 value against the 8th filial-generation adults was measured. Results After mice were infected with the mixture of cercariae of PZQ-resistant and -sensitive S. japonicum isolates at a ratio of 1:1, the praziquantel ED50 was 135.2 mg/kg against the adults of the 8th filial-generation parasite. After mice were infected with the mixture of cercariae of PZQ-resistant and -sensitive S. japonicum isolates at a ratio of 2:1, the praziquantel ED50 was 129.2 mg/kg against the adults of the 8th filial-generation parasite. In addition, the praziquantel ED50 was 208.4 mg/kg against the adults of the 8th filial-generation S. japonicum without the selection pressure of praziquantel. Conclusions Compared with the experimentally induced praziquantel-resistant S. japonicum isolate, the adult worms of the filial-generation S. japonicum show a reduced sensitivity to praziquantel in the same host following infection with the mixture of cercariae of praziquantel-resistant and -sensitive S. japonicum isolates. The adult worms of the filial generation of the praziquantel-resistant S. japonicum isolate without the selection pressure of praziquantel may still maintain the resistance to praziquantel.
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OBJECTIVE@#To compare the median effective dose (ED) of intranasal dexmedetomidine for procedural sedation in uncooperative pediatric patients with acyanotic congenital heart disease before and after cardiac surgery.@*METHODS@#We prospectively recruited 47 children (22 in preoperative group and 25 in postoperative group) who needed sedation for transthoracic echocardiography (TTE). A modified up-and-down sequential study design was employed to determine dexmedetomidine dose for each patient with a starting dose of 2 μg/kg in both groups; dexmedetomidine doses for subsequent subjects were determined according to the responses from the previous subject using the up-and-down method at a 0.25 μg/kg interval. The ED was determined using probit regression. The onset time, examination time, wake-up time and adverse effects were measured, and the safety was evaluated in terms of changes in vital signs every 5 min.@*RESULTS@#The ED value of intranasal dexmedetomidine for sedation was 1.84 μg/kg (95% : 1.68-2.00 μg/kg) in children with congenital heart disease before cardiac surgery, and 3.38 μg/kg (95% : 3.21-3.54 μg/kg) after the surgery. No significant difference was found between the two groups in the demographic variables, onset time, examination time, wake-up time, or adverse effects.@*CONCLUSIONS@#In children with acyanotic congenital heart disease, the ED of intranasal dexmedetomidine for TTE sedation increases to 3.38 μg/ kg after cardiac surgery from the preoperative value of 1.84 μg/kg.
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Child , Humans , Administration, Intranasal , Cardiac Surgical Procedures , Dexmedetomidine , Heart Defects, Congenital , General Surgery , Hypnotics and SedativesABSTRACT
OBJECTIVE:To determine the median effective dose (ED50) of propofol with single intravenous injection in alcohol dependence or withdrawal model rats,and to observe the anaesthetic effect of 2-fold ED50 propofol. METHODS:Fifty SD rats were divided into drinking group(n＝23)and control group(n＝27)based on whether the consumption of alcohol was greater than 3.0 g/(kg·d). Drinking group continued to drink freely and intermittently to establish alcohol dependence model. Control group was only given drinking water for ethanol elution 16 rats were randomly selected from each group to determine ED50 of propofol with single intravenous injection by sequential method,and initial dose was 6.02 mg/kg. After eluting for a week,alcohol dependence rats stopped drinking for 24 hours and had alcohol withdrawal symptoms to establish alcohol withdrawal model. ED50 of propofol in alcohol withdrawal group and control group were determined with same method. After eluting for a week,anaesthetic effect [disappearance time and reappearance time of forepaw righting reflex(FRR),time of activity complete recovery] of 2-fold ED50 propofol with single intravenous injection were observed in alcohol dependence group,alcohol withdrawal group and control group,and corresponding time point and the frequency of respiration before administration were also observed. Changes of liver function indexes(serum albumin,alanine transaminase,total bilirubin,γ glutamyl transaminopeptidase)and liver histomorphology were observed 48 h after medication,10 in each group. RESULTS:ED50 of propofol in alcohol dependence model rats was 9.563 mg/kg,which was higher than 5.623 mg/kg of control group. ED50 of propofol in alcohol withdrawal model rats was 4.086 mg/kg,which was lower than 5.297 mg/kg of control group. Compared with control group,reappearance time of FRR was prolonged significantly in alcohol dependence group and alcohol withdrawal group (P＜0.05). There was no statistical significance in disappearance time of FRR or activity complete recovery time (P＞0.05). The frequency of respiration during FRR disappearance was lower than before propofol injection,FRR reappearance and activity complete recovery (P＜0.01). After intravenous injection of 2-fold ED50 propofol,reappearance time of FRR in alcohol dependence group and alcohol withdrawal group were longer than control group(P＜0.05)；the alcohol dependence group was longer than the alcohol withdrawal group(P＜0.05).The time of activity complete recovery in alcohol dependence group was longer than control group and alcohol withdrawal group (P＜0.05). The frequency of respiration in 3 groups during FRR disappearance were all lower than before propofol injection,FRR reappearance and activity complete recovery(P＜0.01). There was no significant difference in the change of liver function indexes or liver histomorphology. CONCLUSIONS:ED50 of propofol is increased in alcohol dependence rats,while ED50 of propofol is decreased in alcohol withdrawal rats. 2-fold ED50 of propofol has no significant toxicity to liver function.
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Objective To observe the effect of ultrasound-guided transversus abdominis plane blockon median effective dose of sufentanil in pediatric postoperative analgesia. Methods Forty-fivepediatric patients under-going elective hernia repairsurgery were randomly divided into two groups:group Rop and group Sal. Ultrasound-guided transversus abdominis plane blocks were performed on both groups after general anesthesia induction before the start of surgery. Group Rop received 0.3 mL/kg of 0.25%ropivacaine,and group Sal received 0.3 mL/kg of 0.9%saline. Patient controlled intravenous analgesia pump within sufentanil was used in both groups after operation. Used the sequential method to determine the median effective dose of sufentanil ,recorded the times of the pressing self-control analgesia within 6h after operation,the use of sufentanil,postoperative pediatric pain(FLACC)score and adverse reactions. Results 1. The median effective dose of sufentanil in group Rop was lower than group Sal (0.0259 μg/(kg · h)vs 0.0379 μg/(kg · h)). 2.The times of the pressing self-control analgesia within 6 h after operation and the use of sufentanil in group Rop were less than in group Sal. 3.The postoperative FLACC score at different points in group Rop was lower than in group Sal(P < 0.05). 4.There were no significant difference(P >0.05)in incidence of adverse reactions in both groups. Conclusion The ultrasound-guided transversus abdominis plane block in pediatric lower abdominal surgery can effectively reduce the median effective dose of sufentanil.
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Objective Evaluate the interaction between dexmedetomidine and propofol for seda-tion induction.Methods Seventy-five patients who undergoing elective surgery under general anesthe-sia,36 males and 39 females,aged 18-65 years,BMI 20-25 kg/m2,ASA physical status Ⅰ or Ⅱwere randomly divided into three groups (n=25 ):propofol group (group A),dexmedetomidine group (group B),propofol combined dexmedetomidine group(group C),each group was divided into 5 groups according to different drug doses,the dose ratio of the adjacent two groups was 1.25,and the median effective dose (ED50)value was calculated by the point oblique method.Results The hyp-notic dose of propofol ED50in group A was 1.25 mg/kg (0.90-1.45 mg/kg),and the anesthetic induction dose of dexmedetomidine ED50in group B was 1.35 μg/kg (0.95-1.50 μg/kg),and the hypnotic dose of propofol and dexmedetomidine ED50in group C was 0.65 mg/kg (0.50-0.90 mg/kg)and 0.40 μg/kg (0.34-0.65 μg/kg)respectively.Conclusion Dexmedetomidine combined with propofol can produce a sig-nificant hypnotic effect,while reducing the impact on the circulation.
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Objective To evaluate the median effective anesthetic dose of ropivacaine in ultrasound-guided transversus abdominis plane ( TAP ) block for analgesia in patients undergoing appendectomy. Methods Twenty-eight cases of appendectomy under general anesthesia were analyzed.After standardized general anaesthesia,a bilateral ultrasound-guided TAP block was performed on patients undergoing appendectomy using ropivacaine. Sequential method was applied. The initial dose of ropivacaine in first patient was 1.6 mg·kg-1,the dose adjustment interval was 0.2 mg·kg-1.Numerical Rating Scale was used to estimate the level of pain postoperatively. If NRS≤3, dosage of ropivacaine was decreased by 0. 2 mg·kg-1. The transversus abdominis plane block analgesia duration and incidences of postoperative adverse reactions were analyzed. Results Median effective dose (ED50) of ropivacaine in ultrasound-guided transversus abdominis plane block was 2.73 mg·kg-1.95%CI (1.94, 3.84) mg·kg-1. Conclusion The determination of ED50of ropivacaine in ultrasound-guided transversus abdominis plane block improved the anesthesia efficacy and safety.
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Objective To observe the minimum effective local anesthetic dose of intra-articular ropivacaine with dexmedetomidine for analgesia after knee arthroscopy in patients.Methods Seventy-two patients (35 males,37 females,aged 60-75 years,ASA grade Ⅰ or Ⅱ)undergoing knee arthro-scopy under total intravenous anesthesia were randomly divided into two groups (n =36 each):ropiv-acaine group (group R)and ropivacaine with dexmedetomidine group (group DR);Ropivacaine was injected intra-articularly in group C,and dexmedetomidine 1 μg/kg with ropivacaine was injected intra-articularly in group DR.ED50 of ropivacaine was determined by the sequence method.VAS score3 two hours after operation was rated as effective.The initial dose was 3 mg and according to the effective or ineffective results in previous patient,a dose of ropivacaine was decreased or increased 1.1 times to the previous patient.BP,HR,VAS Score,and OAA/S score were recorded five minutes preoperatively(T0 ),1 h (T1 ),2 h (T2 ),3 h (T3 ),6 h (T4 ),12 h (T5 ),24 h (T6 ),and 48 h (T7 ) after operation in two groups.Results There was no significant difference between the two groups with regard to the BP,HR,VAS Score,and OAA/S score.ED50 of ropivacaine for analgesia after knee arthroscopy was 0.31% (95%CI 0.30%-0.32%),and ED50 of ropivacaine with dexmedetomi-dine for analgesia after knee arthroscopy was 0.14% (95% CI 0.14%-0.1 5%). Conclusion Intra-articular administration of ropivacaine with dexmedetomidine could provide superior postoperative analgesia.The dose of ropivacaine for analgesia after knee arthroscopy should be reduced when combined with dexmedetomidine in patients.
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Objective To study the optimal dose of esmolol for maintaining cardiovascular stability in patients with hypertension during tracheal extubation. Methods In post-anestheisa care unit, hypertensive patients after general anesthesia meeting the extubation criteria were included. Patients were divided into 2 groups according the age: group Ⅰ (>65 years old for the elderly hypertensive, 21 cases), and groupⅡ(≤65 years old for the non-elderly hypertensive, 22 cases). All the patients received esmolol bolus before sputum suction and tube extraction, and the tracheal extubation were extubated 2 minutes after esmolol bolus. The systolic blood pressure, diastolic blood pressure and heart rate were was recorded before tracheal extubation, 2 min after esmolol bolus, at the time of sputum suction extubation, 1 min after tracheal extubation, 3 min after tracheal extubation and 5 min after tracheal extubation. Esmolol dose was determined by the up and down method. Initial dose was 0.5 mg/kg, in accordance with the arithmetic dose (0.2 mg/kg) increasing or decreasing progressively. In negative results (the systolic blood pressure at extubation or 5 min after extubation ≥ 20% of the base, or the systolic blood pressure at sputum suction extubation>180 mmHg, 1 mmHg=0.133 kPa) esmolol dose increased progressively, and in positive results (the systolic blood pressure at extubation or 5 min after extubation<20%of the base) esmolol dose decreased progressively. When the crosspoint (from positive to negative result) reached 6, the study was terminated. Results The median effective doses of esmolol for maintaining cardiovascular stability in groupⅠand groupⅡwere (0.6 ± 0.1) and (0.8 ± 0.1) mg/kg. Conclusions Esmolol can maintain cardiovascular stability in patients with hypertension during tracheal extubation. Median effective dose decreases in older hypertensive patients.
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Objective To determine the median effective dose of remifentanil for maintaining the tolerance to ProSeal laryngeal mask airway in awake and spontaneously breathing patients.Methods Sixty ASA Ⅰ orⅡpatients aged 20-55 years old were recruited.Sixty patients was randomized into six groups with 10 case each Remifentanil was infused in a dose of 0.061,0.048,0.039,0.03,0.025 or 0.02μg·kg~(-1) 5 minutes after inserting PLMA.Single dose of remifentanil 0.25/μg/kg was given before continuous intravenous infusion.Respiratory response subscore of comfort scale(CSRR)and Ramsay sedation scale(RSS)were recorded after 25 minutes.ED50 was calculated.Results The ED50 of remifentanil for ProSeal laryngeal mask airway tolerance was 0.027μg·kg~(-1)(95%CI:0.023-0.030μg·kg~(-1)·min~(-1)in awake and spontaneously breathing patients.Conclusion The patients tolerate stimulus of laryngeal mask with a low dose continuous intravenous infusion of remifentanil in awake.and can maintain the hemodynamics stable.
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AIM: To determine the median effective dose(ED50) of spinal anesthesia 0.75% ropivacaine for cesarean section. METHODS: Thirty-two ASAⅠ-Ⅱ parturients undergoing elective cesarean section delivery with use of combined spinal-epidural anesthesia were enrolled in this study. The initial dose of was 12.8 mg of 0.75% ropivacaine, and the dosing intervals were 98.4% of the preceding dosage. Doses for subsequent parturients were determined by the response of the previous parturient. Successful anesthesia was defined as a loss of sensation to an acupuncture stimulus at the T7 level, full motor blockade within 10 minutes after administration of the local anesthetic, analgesia of incision and the satisfaction of skelaxin evaluated by one operator. ED50 and its 95% confidence interval (CI) was determined with use of Dixon method. RESULTS: Five parturients were rejected out the study because of doubtful anesthsia. According to the rest twenty-seven parturients' data, the ED50 of intrathecal 0.75% ropivacaine was 11.97 mg (95% confidence interval [CI], 11.75-12.19 mg). CONCLUSION: The ED50 of spinal 0.75% ropivacaine for cesarean delivery under the conditions of this study were 11.97 mg.
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Objective:To investigate the antiinflammatory effect of Chai Ge Oral Liquid.Methods:The antiinflammatory effect on mice feet swelling caused by carrageena and ear swelling caused by xylene was observed.Results:The inflammation of mice feet and ear swelling apparently was refrained by Chai Ge Oral Liquid,The median effective dose(ED 50 ) was 0.41ml/kg.Conclusion:Chai Ge Oral Liquid has antiinflammatory effect.