RESUMEN
Objective To explore the correlation of heart rate variability(HRV)and cardiac output by PICCO with anesthetic depth by Narcotrend monitoring. Methods 60 patients with radical resection of esophageal cancer were enrolled in the study. PICCO was used to monitor ECG and Narcotrend was use to monitor anesthetic depth.The NT value,NT grade,Cardiac index(CI),heart rate(HR),mean arterial pressure(MAP),cardiac output(CO),Poincare scattergram Scatter plot minor axis(SD1)and scatter plot major axis(SD2)were recorded and measured at the time points of pre-anesthesia induction(T1),post-successful intubation(T2),tracheal intu-bation moment(T3),lung collapse for 30 min(T4),post-lung ventilation(T5)and 10min after operation(T6). Results Person's correlation analysis showed that during the monitoring period(T1-T6),CI,CO,SD1 and NT showed a low linear correlation(P < 0.001);SD2 was significantly correlated with NT(P <0.001). There was a low linear correlation between CI,CO,SD1,SD2 and NT at the operation time(T2-T5). Conclusion During general anesthesia,heart rate variability(SD1,SD2)and cardiac output(CO)are correlated with the NT value of anesthesia depth.Collaborative monitoring could help to enhance the safety of anesthesia.
RESUMEN
Objective To explore the effects of general anesthesia combined thoracic paraverte-bral block on postoperative pain and fast track single-port video-assisted thoracoscopic surgery (VATS).Methods Thirty patients,including male 20 and female 10,received single-port VATS were randomly and equally divided into two groups:group C received general anesthesia only,and group T received ultrasound-guided thoracic paravertebral nerve block combined with general anesthe-sia.Both groups did not use the patient-controlled analgesia,if insufficient analgesia happened (rest-ing VAS scores>4),than used dezocine intravenously as additional analgesia (a single-dose 5-20 mg, no more than 120 mg per day).The Ramsay scores at 1,4,8,12 h after the surgery and the mechani-cal withdrawal threshold on the day before the surgery,at 4,8,12,24 h after the surgery were recor-ded.The first time of post-operation pain feedback,the consumption of dezocine in the first 24 h after surgery,the incidence rates of side effects,the first time off-bed and the hospital stays were also re-corded.Results Compared with group C,the Ramsay scores at 8,12 h postoperatively in group T significantly decreased (P <0.05),and the mechanical withdrawal threshold at 4,8 h postoperatively significantly increased (P <0.05).The first time of post-operation pain feedback in group T was sig-nificantly longer than group C (P <0.05).The consumption of dezocine in the first 24 h after surgery significantly decreased in group T (P <0.05).The first time off-bed and the hospital stays in group T were shorter than group C (P <0.05).Also,the incidence rates of nausea,vomiting in the first 24 h postoperatively were lower in group T (P < 0.05 ).Conclusion General anesthesia combined with single-injected thoracic paravertebral nerve block can effectively relieve the postoperative pain in pa-tients undergoing single-port VATS,reduce the consumption of opioids in the first 24 h postopera-tively,cutting down the occurring rates of adverse reactions,which was beneficial to early ambulate and shortened the hospital stays.
RESUMEN
Objective To explore the correlation of patient-controlled sedation of dexmedetomidine and Narcotrend values. Methods Forty patients with lower limb surgery were enrolled. Until CSEA block fixed , the electronic pump ran the patient-controlled sedation of dexmedetomidine. The parameter of electronic pump was set as follows: load dose 2 mL + background dose 1.5 mL/h + single dose 0.5 mL + locktime 20 s. The heart rate , mean arterial pressure, pressing times, effective times, OAA/S sedation scores and NI values were determined. Results At T4 point, the patients reached appropriate sedation. At T4 ~ T9 OAA/S scores kept 3 to 4. From T5 point, NI values showed significant decrease. After the T7 point. OAA/S scores and NI values reached the plateau time of (7.5 ± 1.8) min and (13.1 ± 3.4) min, OAA/S scores of 1, 2, 3, 4, respectively, corresponding roughly with NI values 95 to 100, 90 to 94, 65 to 89, 40 to 64. The correlation coefficient was 0.58. The time of NI values significant decreased in the younger group and in the elderly group, with (10.2 ± 1.6) min and (14.4 ± 2.2) min. In T5~ T9 point, NI values of the younger group were significantly lower than those in the elderly group. Conclusion Relevant relationships are observed between dexmedetomidine patient-controlled sedation depth and the narcotrend values under CSEA.
RESUMEN
Objective To deter mine the effect-site concentration of sufentanil blunting responses to tracheal intubation with video laryngoscope during propofol target controlled infusion (TCI). Methods Twenty-three patients undergoing selective surgery under general anesthesia were enrolled in this study. Induction of anesthesia was initiated by TCI sufentanil at the target effect-site concentration 3 min later , TCI of propofol began at the target plasma concentration of 3 μg/mL. Cisatracurium 0.15 mg/kg was ad ministrated for video laryngoscope tracheal intubation after loss of consciousness. The target concentration of sufentanil for consecutive patients was deter mined using the modified Dixon′s up-and-down method by the intubation response of the previous patient , in an increment or decrement of 0.05 ng/mL. The initial concentration was set at 0.4 ng/mL. Results The EC50 of Sufentanil was 0.32 ng/mL with 95%confidence interval of 0.29~0.35 ng/mL; the EC95 was 0.38 ng/mL with 95%confidence interval 0.35-0.55 ng/mL during video laryngoscope tracheal intubation. Conclusion The EC50 and EC95of sufentanil blunting responses to tracheal intubation with video laryngoscope are 0.32 ng/mL and 0.38 ng/mL during propofol TCI.
RESUMEN
BACKGROUND: Therapeutic methods for of peripheral facial nerve injury include surgery, physical therapy and drug treatment, but the treatment effect is not ideal in some certain cases. OBJECTIVE: To study the effect of autologous platelet rich plasma on repair of facial nerve injury. METHODS: The bilateral destroyed buccal nerve branches of the 10 white rabbits were put in silica gel nerve regeneration chamber, one side injected with platelet rich plasma as experimental group, the other side injected with normal saline as control group. The general observation, neuroelectrophysiology detection, histological observation, image analysis and evaluation of facial nerve regeneration recovery were performed at 8 weeks after surgery. RESULTS AND CONCLUSION: The action potential latency of the orbicularis oris at the experimental side was significantly lower than that at the control side, and the action potential amplitude (M wave) of compound nerve muscle of the experimental side was significantly higher than that of the control side (P < 0.01). Compared with the control side, the regenerative nerves of the experimental side were more mature with more regenerative axons, and the differentiation of myelin sheath was more mature and the thickness of myelin sheath was wel -distributed. Meanwhile, the diameters of axons were closed to the normal diameter, and the nerve axons were more intensive and arranged more regularly, the outer membrane of nerve fiber was thicker and the col agen fiber and elastic fiber layer were increased when compared with the control group. The number of regenerative axons of the control side was less, and the axons were distributed irregularly and poorly developed, and a large number of fibrous connective tissues were observed. The vacuolar degeneration at the control side was more than the experimental side. The regenerated nerve in the experimental side was better than the control side in the diameter of myelinated axon, area, myelin sheath thickness and axon count, and there were significant differences between two groups (P < 0.01). It indicates that platelet rich plasma has a promoting effect in the repair and regeneration of facial nerve.
RESUMEN
In order to successfully develop the effective population pharmacokinetic model to predict the concentration of propofol administrated intravenously, the data including the concentrations across both distribution and elimination phases from five hospitals were analyzed using nonlinear mixed effect model (NONMEM). Three-compartment pharmacokinetic model was applied while the exponential model was used to describe the inter-individual variability and constant coefficient model to the intra-individual variability, accordingly. Covariate effect including the body weight on the parameter CL, V1, Q2, V2, Q3 and V3 were investigated. The performance of final model was assessed by Bootstrapping, goodness-of-fit and visual predictive checking (VPC). The context-sensitive half-times and the infusion rates necessary to maintain the concentration of 1 microg x mL(-1) were simulated to six subpopulations. The results were as follows: the typical value of CL, V1, Q2, V2, Q3 and V3 were 0.965 x (1 + 0.401 x VESS) x (BW/59)(0.578) L x min(-1), 13.4 x (AGE/45)(-0.317) L, 0.659 x (1 + GENDER x 0.385) L x min(-1), 28.8 L, 0.575 x (1 + GENDER x 0.367) x (1 - 0.369 x VESS) L x min(-1) and 196 L respectively. Coefficients of the inter-individual variability of CL, V1, Q2, V2, Q3 and V3 were 29.2%, 46.9%, 35.2%, 40.4%, 67.0% and 49.9% respectively, and the coefficients of residual variability were 24.7%, 16.1% and 22.5%, the final model indicated a positive influence of a body weight on CL, and also that a negative correlation of age with V1. Q2 and Q3 in males were higher than those in females at 38.5% and 36.7%. The CL and Q3 were 40.1% increased and 36.9% decreased in arterial samples compared to those in venous samples. The determination coefficient of observations (DV)-individual predicted value (IPRED) by the final model was 0.91 which could predict the propofol concentration fairly well. The stability and the predictive performance were accepted by Bootstrapping, the goodness-of-fit and VPC. The context-sensitive half-times and infusion rates necessary to maintain the concentration of 1 microg x mL(-1) were different obviously among the 6 sub-populations obviously. The three-compartment model with first-order elimination could describe the pharmacokinetics of propofol fairly well. The involved fixed effects are age, body weight, gender and sampling site. The simulations in 6 subpopulations were available in clinical anesthesia. The propofol anesthesia monitor care could be improved by individualization of pharmacokinetic parameter estimated from the final model.
RESUMEN
Objective To investigate the sedative and hypnotic interaction between remifentanil and propofol by target-controlled infusion (TCI) during induction of anesthesia.Methods Third-two ASA Ⅰ or Ⅱpatients,aged 22-63 yr,body mass index 18-25 kg/m2,scheduled for elective surgery under general anesthesia,were randomly divided into 4 groups(n=8 each).Group Ⅰ only received TCI pmpofol.GroupⅡ,Ⅲ,and Ⅳreceived a target concentration of 2,4 or 6 ng/ml remifentanil respectively.While the blood-effect site concentrations of remifentanil were equilibrated,patients received TCI of propefol,with an initial target concentration of 0.5μg/ml.After the blood-effect site concentrations of propofol were equilibrated then with 0.5μg/ml increments until the loss consciousness was achieved.The eyelash reflex and state of consciousness were assessed and radial arterial blood sample 6 ml was taken every 3 min to determine the remifentanil and propofol concentrations in blood.Propofol and remifentanil concentrations in blood were measured by reversed-phase high-performance liquid chromatography and high-performance liquid chromatography with ultraviolet detection respectively.The sedative and hypnotic interaction between propofol and remifentanil was determined with a pharmacodynamie interaction model by regression analysis and determined using the isobolographic method.Results Propofol concentrations in blood were lower in group Ⅱ,Ⅲ and Ⅳ than group Ⅰ(P<0.05).The propofol concentratopms in blood were significantly decreased in trun with the increase in the remifentanil concentrations in blood in group Ⅱ-Ⅳ(P<0.05).At loss of eyelash reflex and loss of consciousness of patients,the pharmacodynamic interaction model by curve fitting was superior to linear regression (P<0.05).At loss of eyelash reflex of patients,the curve fitting result showed EC50,prop=2.77μg/ml and EC50,rem=26.67 ng/ml,and the isobolographic method equation is ECprop/2.77+ECrem/26.67=0.69.At loss of consciousness of patients,the curve fitting result showed EC50,prop==3.76μg/ml and EC50,rem=31.56ng/ml,and the isobolographic method equation is Ecprop/3.76+Ecrem/31.56=0.65.Conclusion Remifentanil (Cp 2-6 ng/ml) and propofol by TCI shows a synergistic type of pharmacodynamic interaction on the sedative and hypnotic during induction of anesthesia.
RESUMEN
This paper presents a microcontroller system for target controlled infusion according to pharmacodynamic parameters of intravenous anesthetics. It can control the depth of anesthesia by adjusting the level of plasma concentrations. The system has the advantages of high precision, extending power and easy manipulation. It has been used in the clinical anesthesia.
Asunto(s)
Humanos , Anestesia Intravenosa , Métodos , Anestésicos Intravenosos , Farmacocinética , Sistemas de Liberación de Medicamentos , Métodos , Quimioterapia Asistida por Computador , Métodos , Monitoreo Intraoperatorio , MétodosRESUMEN
OBJECTIVE To establish an assay for the simultaneous determination of propofol and lidocaine in human plasma using reversed-phase high performance liquid chromatography（RP-HPLC）.METHODS With thymol and bupivacaine as the internal standards for propofol and lidocaine respectively,the extraction was performed with cyclohexane.The organic layer was evaporated and the residue was redissolved by mobile phase.The concentrations of propofol and lidocaine were assayed on a hypersil BDS C18 column with a mobile phase consisting of acetonitrile-methanol-water（10∶60∶30）（including 0.14% n-butyamine 0.1% acetic acid）at a flow rate of 1 mL*min-1 and detected at 220 nm during 1～7 min and at 273 nm during 7～16 min.RESULTS The linearity between concentrations and peak area ratio was obtained from 0.1 μg*mL-1 to 25.6 μg*mL-1（r=0.998，r=0.9995）.The detection limits were 0.1 μg*mL-1 for propofol and 0.05 μg*mL-1 for lidocaine.The within-day and between-day variation coefficients were less than 5%(n=5).The average recoveries were 93.33%,99.4% and 90%,95.67% respectively.CONCLUSION The method was found to be rapid,accurate and precise.It is suitable for clinical pharmacokinetic and pharmacodynamic study.
RESUMEN
Objective: To perform target-controlled infusion (TCI) in total intravenous anesthesia (TIVA) of propofol and fentanyl. Method: Using effect compartment modeling, computer controlled infusion(the computer software was developed by Coezee and Pina) was performed during induction and maintenance of anesthesia in two groups of adult patients. The target predicted concentration of theoretical effect-site compartment for propofol was 4?g/ml and for fentanyl was 2?g/ml. The plasma concentration (Cm) of propofol was determined by fluorospectrophotometry and Cm of fentanyl was measured with radioimmunoassay. Result: The mean Cm from 0 to 120 min showed that excessive dose of propofol was administered, MDAPE=25%,however the mean Cm of fentanyl was lower than the target level obviously,MDAPE=35.5% in first group. After an imitative calculation,another pharmacokinetic (PK) parameter sets of propofol and fentanyl were selected in the second group,MDAPE=15.5% for propofol and MDAPE=37. 75% for fentanyl. Conclusion: The concentrations of propofol and fentanyl in the effect site compartment can be achieved rapidly by using the effect compartment control algorithm. The PK parameter,described by different authors influences the accuracy of TCI administration.
RESUMEN
Objective To evaluate the effects of fentanyl and lidocaine on hypnotic effect of propofol in total intravenous anesthesia(TIVA) Methods One hundred and sixty ASAI Ⅲ patients(86 male,74 female) aged (55 0?12 4)yr,weighing (58 0?9 8)kg,scheduled for elective surgery were randomly divided into propofol group(group P,n=30), propofol fentanyl group(group PF,n=52) and propofol lidocaine group (group PL,n=78) Patients with kidney and liver dysfunction, hypertension, neurological and mental disease were excluded All patients were premedicated with intramuscular phenobarbital 0 1g and atropine 0 5mg BP,HR,SpO 2 and BIS were continuously monitored The patients were anesthetized by TIVA with TCI The target plasma concentration for fentanyl was 2?g/L(group PF) and for lidocaine 4mg/L(group PL) The initial target plasma concentration of propofol was set at 1mg/L When pre set concentration was reached, target propofol plasma concentration was increased by increments of 0 5mg/L until loss of consciousness Blood samples were taken before anesthesia(T 0), loss of consciousness(T 1), immediately after intubation(T 2), at skin incision(T 3), 5 and 10 min after skin incision(T 4,T 5), when TIVA was ended (T 6) and when the patient waked up(T 7) for determination of plasma concentrations of propofol, fentanyl and lidocaine Results ED 90 and ED 50 of propofol for loss of consciousness were lower in group PF and PL than those in group P but the difference was of no statistical significance (P
RESUMEN
Objective To study the influence of age on the pharmacodynamics of propofol including the relationship between plasma concentrations of propofol and the time of loss of consciousness or return of consciousness.Methods Forty-two ASAⅠ-Ⅱ patients were assigned to one of three age groups: group A: age ranged from 18-34 yr(n=14); group B:35-60 yr(n=15); and group C: 61-90 yr(n=13). Once spinal anesthesia was completed, propofol infusion at the rate of 0.5 mg?kg -1?min -1(group A) or 0.4 mg?kg -1?min -1(group B and C )was started until burst suppression of EEG lasting 3s was observed. Venous blood samples were taken at 1, 2, 4, 8,10, 15, 30, 45,60,90,120 and 240 min after the start of propofol infusion for the determination of plasma propofol concentrations. The influence of age on relationship between propofol plasme concentration and loss of consciousness or return of consciousness was analyzed by non-linear regression. The relationships between age and time of loss of consciousness,duration of sleep,the total dose of propofol,the plasma concentration at the time of loss of consciousness or return of consiousness were determined by linear regression.Results As compared with those in group A and B,the time of loss of consciousness and the total dose of propofol required decreased markedly in group C. The observation showed increased sensitivity to propofol in elderly patients. The EC50 values for loss of consciousness were 2.86 (at age of 25 yr),2.26 (at 50yr), and 1.78 (at 75yr) ?g?ml -1,and the EC50 values for return of consciousness of 1.76 (at 25 yr),1.45(at 50yr),1.11(at 75yr)?g?ml -1 respectively.Conclusions Elderly patients are more sensitive to propofol than younger people in terms of hypnosis and EEG effects.
RESUMEN
Objective To study the influence of lidocaine on the propofol concentration effect relationships for loss of eyelash reflex and loss of consciousness,hemodynamic function Methods Thirty eight patients were randomly allocated to receiving a computer controlled infusion of lidocaine at target concentration of 0?g?ml -1 (group A,n=9),1 25?g?ml -1 (group B,n=7), 2 5?g?ml -1 (group C,n=7), 5?g?ml -1 (group D,n=8),or 7?g?ml -1 (group E,n=7) respectively While the target concentration of lidocaine was kept stable, propofol was administrated with a computer controlled infusion at an initial target concentration of 0 5 1?g?ml -1 , which was increased every time by 0 5?g?ml -1 until loss of consciousness Plasma concentrations of lidocaine and propofol were measured with high performance liquid chromatography Results 50% of patients lost eyelash reflex and consciousness at plasma propofol concentrations(Cp50) of 1 78 and 3 17?g?ml -1 in the absence of lidocaine In the presence of plasma lidocaine concentration of 1 25 4 3 ?g?ml -1 ,the Cp50 for loss of eyelash reflex was reduced by 42 1% There was a linear regression relationship between plasma lidocaine concentrations from 0 to 7?g?ml -1 and the Cp50 for loss of consciousness (r=-0 69 ) Conclusions The Chinese Cp50 for loss of eyelash reflex and consciousness are lower than those reported abroad Plasma lidocaine concentration at 4?g?ml -1 can potentiate properly the potency of propofol on the sedation and hypnosis during anesthesia induction
RESUMEN
To study the effects of fentanyl on the MAC of sevoflurane. Method: One hundred and sixteen patients were given continuous infusion of fentanyl with CACI-pump (computer-assisted continuous infusion)to maintain different target plasma concentrations (Ct), meanwhile inhaled sevoflurane. All patients were randomly divided into seven groups receiving sevoflurane in oxygen with fentanyl target plasma concentration of 0?g/L (n=16), 0.5?g/L(n=20), 1?g/L(n=18), 2?g/L(n=16), 3?g/L(n=18), 4?g/L(n= 14) or 6?g/L(n= 14). Plasma concentraion of fentanyl was measured with radioimmunoassay. MAC determination, in response to the stimulus of skin incision, was made using the "up-down" method and logistic regression. Result: The MAC of sevoflurane from group 1 to group 7 were 1.94%, 1.89%, 1.55%, 1.29%, 1.09%, 0.86% and 0.35% respectively. Conclusion: We verify the MAC of sevoflurane, which is reduced by increasing plasma fentanyl concentration.
RESUMEN
OBJECTIVE:To study the accuracy of infusion of Midazoloam with plasma concentration as target. METHODS:The parameters of Midazoloam obtained from our researches were inputted into target-controlled infusion(TCI) system with C language. The clinical anesthesia of 12 patients undergoing selective operations was completed with plasma concentration as target-controlled infusion. Predicted value of plasma concentration of Midazoloam was compared with measured value. Parameters of Midazoloam sample were calculated such as performance error(PE),absolute performance error(absPE),median performance error(MDPE),median absolute performance error(MDAPE),constancy error(CE),absolute constancy error(absCE),median constancy error(MDCE) and median absolute constancy error(MDACE). RESULTS:PE,absPE,MDPE and MDAPE of plasma concentration were -2.57%,14.16%,-3.28% and 15.34%,respectively. CE,absCE,MDCE and MDACE were 0.06%,1.42%,0.03% and 1.21%,respectively. The measured values were in indirect relationship with predicated values(r=0.986,P
RESUMEN
OBJECTIVE:To study the clinical pharmacokinetics of Midazolam.METHODS:Fourteen patients undergoing general anesthesia with Midazolam in combination with remifentanil and isoflurane were enrolled in our study.The midazolam was administered by constant-rate infusion of 20 ?g?kg-1?min-1 for 20 min.The sampling of radial artery blood samples(3 mL/sample)were schedule before the infusion and at 1,3,5,7,10,15 and 20 min after the initiation of infusion and at 5,15,30,45 min and 1,2,4,6,12,18,24 h following the completion of midazolam.The plasma midazolam concentrations were determined by RP-HPLC.The pharmacokinetic analysis was performed using DAS2.1.1 program.RESULTS:The concentration-time curves of midazolam were best described by a simple three-compartment open model in which the weight coefficient was 1 and the typical pharmacokinetics parameters of midazolam were as follows:t1/2?=9.584 2 min,t1/2?=85.367 7 min,t1/2?=339.736 5 min,V1(the distribution volume of central compartment)=0.182 1 L?kg-1,CL=119.434 4 mL?h-1?kg-1,K10=0.045 8 min-1,K12=0.086 3 min-1,K21=0.017 5 min-1,K13=0.013 3 min-1,K31=0.002 4 min-1.CONCLUSION:t1/2?,t1/2?,t1/2? and CL were in line with those reported in the literature abroad,but V1 is on the lower side and it is easy for the medication to reach a balance.However,the rapid clearance of midazolam is more in line with the pharmacokinetic parameters of the Chinese subjects.
RESUMEN
This paper introduces such information of a LCD graphic display system based on SED1335 as its hardware link with the singlechip computer Atmega128 and the design of system display software. With a simple, compact and stable circuit, this system can be applied to portable medical signal monitoring and controlling equipments.