Remifentanil In Elderly Patients Research Articles

Effect of remifentanil and midazolam on ED95 of propofol for loss of consciousness in elderly patients: A randomized, clinical trial.

Background:Older people are more vulnerable to hemodynamic instability caused by propofol due to their decreased initial distribution volume and increased sensitivity to propofol. Midazolam or remifentanil can often be coadministered because of their synergistic or additive effects with propofol as well as amnesic properties and the blockade of sympathetic stimulation. However, no study has confirmed the appropriate dose of propofol for loss of consciousness in aged patients when administered with other drugs, including opioids or benzodiazepines.Methods:Patients >65 years scheduled for general anesthesia were enrolled. The patients were randomized into 3 groups using a computer-generated randomization table. Patients in group P (propofol) received only propofol for loss of consciousness, those in group PR (propofol–remifentanil) received remifentanil before propofol, and those in group PMR (propofol–midazolam–remifentanil) received remifentanil and midazolam before propofol. After propofol administration, loss of both eyelash reflex and verbal response represented success. The 95% effective dose of propofol for loss of consciousness in each group, which was the primary outcome, was determined using a modified biased coin up-and-down method.Results:In total, 120 patients were randomized into the 3 groups (n = 40). The 95% effective dose of propofol for loss of consciousness was 1.13, 0.87, and 0.72 mg/kg in groups P, PR, and PMR, respectively. The mean blood pressure (MBP) in group PMR was more significantly decreased before propofol injection (P = .041) as well as 2 minutes (P = .005) and 3 minutes after propofol administration (P<.001), compared with group P, but there were no intergroup differences at other time points.Conclusions:The effective dose of propofol for loss of consciousness in elderly patients could be decreased by 23% and 36% when remifentanil pretreatment was used without and with midazolam, respectively. However, the decrease in MBP was greater with remifentanil and midazolam pretreatment than with propofol alone. These findings suggest that pretreatment with midazolam for propofol infusions with remifentanil in elderly patients should be cautiously used, due to hemodynamic instability during induction.

Effects of lumbar plexus-sciatic nerve block on postoperative outcome in elderly patients after total hip arthroplasty

Objective To investigate the effects of lumbar plexus-sciatic nerve block combined with general anesthesia on postoperative outcome in elderly patients after total hip arthroplasty. Methods Seventy elderly patients who were scheduled for total hip arthroplasty were randomly divided into two groups: group LPSN (n=35) and group GA (n=35), lumbar plexus-sciatic nerve block combined with general anesthesia were performed in patients of group LPSN, patients in group GA were performed with general anesthesia. saturation of pulse oximetry (SpO2), Visual analogue scale (VAS) before anesthesia (T0), at 3 h (T1), 24 h (T2), 48 h (T3) after anesthesia, operation time, the remifentanil consumption, time to remove the tracheal tube, the incidence of respiratory events and the length of stay were recorded. Results As compared with group GA, the VAS of group LPSN was reduced at T1, T2[(2.5±1.4) vs. (3.2±1.4), (1.9±1.2) vs. (2.7±1.2), P 0.05]. Conclusion lumbar plexus-sciatic nerve block combined with general anesthesia could decrease the use of remifentanil in elderly patients after total hip arthroplasty, have a fewer incidence of respiratory events, and it is beneficial to the early postoperative rehabilitation. Key words: Nerve block; Elderly patient; Arthroplasty; Postoperative outcome

Effect of ear point embedding on plasma and effect site concentrations of propofol-remifentanil in elderly patients after target-controlled induction

To observe the clinical effect of ear point embedding on plasma and effect site concentrations of propofol-remifentanil in elderly patients who underwent abdominal external hernia surgery at the time of consciousness and pain disappearing by target-controlled infusion (TCI) and bispectral index (BIS). Fifty patients who underwent elective abdominal hernia surgery were randomly assigned into an observation group and a control group, 25 cases in each one. In the observation group, 30 minutes before anesthesia induction, Fugugou (Extra), Gan (CO12), Pizhixia (AT4), and Shenmen (TF4) were embedded by auricular needles until the end of surgery, 10 times of counter press each point. In the control group, the same amount of auricular tape was applied until the end of surgery at the same points without stimulation 30 minutes before anesthesia induction. Patients in the two groups were given total intravenous anesthesia, and BIS was monitored by BIS anesthesia depth monitor. Propofol was infused by TCI at a beginning concentration of 1.5μg/L and increased by 0.3μg/L every 30s until the patients lost their consciousness. After that, remifentanil was infused by TCI at a beginning concentration of 2.0μg/L and increased by 0.3μg/L every 30s until the patients had no body reaction to pain stimulation (orbital reflex). Indices were recorded, including mean arterial pressure (MAP), heart rate (HR) and the BIS values, at the time of T0 (entering into the operation room), T1 (losing consciousness) and T2 (pain relief), the plasma and effect site concentrations of propofol at T1, the plasma and effect site concentrations of remifentanil at T2. After surgery we recorded the total amounts of propofol and remifentanil, surgery time and anesthesia time. At T1 and T2, MAP and HR of the observation group were higher than those of the control group (P<0.05, P<0.01). At T1, the plasma and effect site concentrations of propofol in the observation group were significantly lower than those in the control group (P<0.05, P<0.01). At T2, the plasma and effect site concentrations of remifentanil in the observation group were significantly lower than those in the control group (P<0.05, P<0.01). There was no significant difference in BIS values at T1 and T2 between the two groups (bothP>0.05). There was no significant difference in operation time and anesthesia time between the two groups (bothP>0.05). The total amount of remifentanil in the observation group was significantly lower than that in the control group (P<0.01). There was no significant difference in the total amount of propofol between the two groups (P>0.05). Ear points embedding combined with propofol-remifentanil TCI could reduce the plasma and effect site concentrations of propofol and remifentanil and the total amount of remifentanil in elderly patients with extra-abdominal hernia surgery, and had the effect of assisting sedation and analgesia.

Effect-site concentration of remifentanil for preventing cough during emergence in elderly patients undergoing nasal surgery: a comparison with adult patients.

PurposePrevention of cough during emergence after nasal surgery is important for avoiding surgical site bleeding. We investigated the remifentanil effect-site concentration in 50% (EC50) of the elderly patients undergoing nasal surgery for smooth emergence without cough and compared it with that of adult patients.MethodsTwenty-two elderly (aged 65–80 years) and 25 adult patients (aged 20–60 years) with an American Society of Anesthesiologists physical status I/II undergoing nasal surgery were enrolled. Anesthesia was maintained with sevoflurane and remifentanil. Remifentanil EC50 and EC95 for preventing cough were determined using the modified Dixon’s up-and-down method and isotonic regression with bootstrapping approach. Recovery profiles were also recorded.ResultsWith Dixon’s up-and-down method, the EC50 of remifentanil in elderly patients (2.40±0.25 ng/mL) was not significantly different from that of adults (2.33±0.30 ng/mL) (P=0.687). With isotonic regression, the EC95 of remifentanil in elderly patients (3.32 [95% confidence interval: 3.06–3.38] ng/mL) was not significantly different from that of adults (3.30 [95% confidence interval: 2.96–3.37] ng/mL). However, eye opening time (14.1±3.8 vs 12.0±2.9 seconds), extubation time (17.2±4.1 vs 14.0±3.0 seconds), and postanesthesia care unit duration (44.5±7.6 vs 38.7±3.4 minutes) in elderly patients were significantly longer than those in adults (P<0.05).ConclusionRemifentanil EC50 for preventing cough after nasal surgery with sevoflurane anesthesia did not differ between elderly and adult patients. However, delayed awakening and respiratory adverse events may warrant attention in elderly patients.

Comparison of dezocine and remifentanil in elderly patients with painless gastroscopy

Objective To investigate the clinical application of dezocine and remifentanil in elderly patients with painless gastroscopy. Methods According to random number table,180 elderly patients undergoing painless gastroscopy were randomly divided into dezocine group(group D),remifentanil group(group R)and control group(group C), each group 60 cases.Group D was infusion with dezocine 20μg/kg,Group R was infusion with remifentanil 0.5μg/kg and Group C was infused with normal saline, then three groups patients, respectively,after the interval of 1minutes were given propofol 1mg/kg. Objects induced sum of propofol, starting time, awakening time, discharged time,HR,MAP and Sp O2 during operation, sedation scores, postoperative side effects such as nausea and vomiting were observed. Results The decrease of MAP was alleviated in group D compared with group C and group S(t DR=2.278,P DR<0.05 and t DC=2.545,P DC<0.05).Sp O2 in group C and group R were significantly lower than that in group D(t DR=2.184,P DR<0.05 and t DC=2.206,P DC<0.05). The time for regaining consciousness(t DC=5.401 and t RC=6.674)and propofol dosage(t DC=3.726 and t RC=4.213)in group D and group R were significantly lower than those in group C(P<0.05).The Ramsay of group D was(2.3±0.7)points,which was lower than(3.8±1.2)points of group C,(3.6±0.9)points of group R(t DC= 8.938,P DC<0.01;t DR=7.154,P DR<0.01),and there were fewer adverse reactions in group D. Conclusion Dezocine is more suitable for the elderly patients than remifentanil, which has exact effect of anesthesia, less respiratory depression, higher level of consciousness awakening and fewer adverse reactions. Key words: Anesthesia; Dezocine; Remifentanil; Gastroscopy; Aged

A comparison of the hemodynamic changes and propofolinduced pain at two different doses of remifentanil in elderly patients.

BackgroundThe purpose of this study was to determine the optimal dose of remifentanil for minimizing hemodynamic changes during intubation and reducing propofol-induced pain in elderly patients.MethodsIn a randomized prospective study, 60 patients (ASA I-II, elder than 65 years) were enrolled to determine which of two target remifentanil blood concentrations (3 ng/ml, 5 ng/ml) was required to blunt hemodynamic changes during intubation and to reduce propofol-induced pain. After the target effect site concentration of remifentanil had been reached, the target controlled infusion of propofol was started and propofol-induced pain was recorded. Blood pressure and heart rate were recorded at baseline, just before intubation and 1, 3, 5 min after intubation.ResultsThere were no significant differences in the hemodynamic parameters between two groups, but not in arterial pressure at just before intubation and 1 minute after intubation. However, the group R5 (5 ng/ml) showed significantly less intense pain induced by propofol than in the group R3 (3 ng/ml).ConclusionsThe results suggest that the group R5 provide more relief in propofol induced pain than the group R3, but showed great possibility of hypotension and bradycardia in both groups, which means it should be used with cautions in the elderly patients.

Total intravenous anesthesia with a step-by-step target-controlled infusion of remifentanil and propofol in elderly patients

Objective To observe the restrain of stress reaction,circulation stability and the pal-inesthesia from anaesthesia during a step-by-step target-controlled infusion (TCI) of remifentanil in elderly patients under laparoscopic cholecystectomy. Methods Sixty ASA class Ⅰ -Ⅱ patients were randomly di- vided into 5 groups:15 ease each group. A dose of 0.06 mg/kg fentanyl was given in group A,4.0 μg/L blood plasma target level of fentanyl was given in group B,4.0 μg/L blood plasma target level of remifen-tanil was given in group C, and blood plasma target level of remifentanil was given from 2.0 μg/L to 4.0 μg/L step by step in group D during anesthesia. Midazolam, propofol and vecuronium bromide were also given during anesthesia induction. Hemodynamic parameters at T0, T1, T2, T3 and T4 were recorded, and the concentrations of serum corticosteroid, aldosterone and blood sugar determined. The time of extubation, return to ward ,OAA/S score after extubation ,and OAA/S score to 5 was recorded. The use of vasoactive a- gent during operations was also recorded. Results MAP and HR were decreased during anesthesia induc- tion in 4 groups,and more significant in group C (P <0.05 ). MAP and HR were increased during trachea extubation in 4 groups,and more significant in groups A, B (P < 0.05 ). The concentrations of corticoste-roid and aldosterone were increased significantly at T4 compared to T0(P < 0.05 ). The frequency of using vasoactive agents was increased significantly in group C(P < 0.05 ). The time of extubataion, leaving PACU, and OAA/S score to 5 was significantly shortened in groups C, D(P < 0.05 ). The OAA/S scores were significantly higher in groups C, and D than in groups A, and B(P < 0.05 ). Conclusion TCI of remifentanil can restrain stress reaction caused by tracheal intubation and operation stimulation effectively, and provide quickly palinesthesia with high quality in elderly patients, but a step-by-step TCI of remifen- tanil can provide more stable circulation. Key words: Aged ; Target-controlled infusion; Remifentanil; Stress reaction