Anesthesia and analgesia
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Anesthesia and analgesia · Mar 2004
Randomized Controlled Trial Comparative Study Clinical TrialThe pharmacodynamic effects of a lower-lipid emulsion of propofol: a comparison with the standard propofol emulsion.
Using a randomized, double-blind protocol design, we compared a new lower-lipid emulsion of propofol (Ampofol) containing propofol 1%, soybean oil 5%, and egg lecithin 0.6% with the most commonly used formulation of propofol (Diprivan) with respect to onset of action and recovery profiles, as well as intraoperative efficacy, when administered for induction and maintenance of general anesthesia as part of a "balanced" anesthetic technique in 63 healthy outpatients. Anesthesia was induced with sufentanil 0.1 microg/kg (or fentanyl 1 microg/kg) and propofol 2 mg/kg IV and maintained with a variable-rate propofol infusion, 120-200 microg x kg(-1) x min(-1). Onset times to loss of the eyelash reflex and dropping a syringe were recorded. Severity of pain on injection, speed of induction, intraoperative hemodynamic variables, and electroencephalographic bispectral index values were assessed. Recovery times to opening eyes and orientation were noted. The results demonstrated that there were no significant differences between Ampofol and Diprivan with respect to onset times, speed of induction, anesthetic dose requirements, bispectral index values, hemodynamic variables, recovery variables, or patient satisfaction. However, the incidence of pain on injection was more frequent in the Ampofol group (26% versus 6%, P < 0.05). We conclude that Ampofol is equipotent to Diprivan with respect to its anesthetic properties but was associated with a more frequent incidence of mild pain on injection. ⋯ The pharmacodynamic profile of a lower-lipid containing emulsion of propofol (Ampofol) was compared with Diprivan when administered for induction and maintenance of general anesthesia. This preliminary study demonstrated that the two formulations of propofol were equivalent with respect to their induction and maintenance properties. However, Ampofol was associated with a more frequent incidence of pain on injection.
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Anesthesia and analgesia · Mar 2004
Randomized Controlled Trial Comparative Study Clinical TrialIntrathecal and oral clonidine as prophylaxis for postoperative alcohol withdrawal syndrome: a randomized double-blinded study.
In this study, we evaluated the effect of intrathecal and oral clonidine as supplements to spinal anesthesia with lidocaine in patients at risk of postoperative alcohol withdrawal syndrome (AWS). We hypothesized that clonidine would have a prophylactic effect on postoperative AWS. Forty-five alcohol-dependent patients (daily ethanol intake >60 g) scheduled for transurethral resection of the prostate were double-blindly randomized into three groups. All patients received hyperbaric lidocaine 100 mg intrathecally. The diazepam group (DiazG) was premedicated with diazepam 10 mg orally; the intrathecal clonidine group (Clon(i/t)G) received a placebo (saline) tablet and clonidine 150 microg intrathecally; and the oral clonidine group (Clon(p/o)G) received clonidine 150 microg orally. For patients diagnosed with AWS, the Clinical Institute Withdrawal Assessment for Alcohol, revised scale, was used. Twelve patients in the DiazG had symptoms of AWS, compared with two in the Clon(i/t)G and one in the Clon(p/o)G. The median Clinical Institute Withdrawal Assessment for Alcohol, revised scale, score was 12 in the DiazG versus 1 in the clonidine-treated groups. Two patients in the DiazG had severe delirium. Patients receiving oral clonidine had a slightly decreased mean arterial blood pressure 6-12 h after spinal anesthesia (P < 0.05); patients in the DiazG had a hyperdynamic circulatory reaction 24-72 h after surgery. In conclusion, preoperative clonidine 150 microg, intrathecally or orally, prevented significant postoperative AWS in ethanol-dependent patients. ⋯ In this randomized, double-blinded study, clonidine 150 microg both intrathecally and orally prevented postoperative alcohol-withdrawal symptoms in alcohol-dependent men. The effect was superior to that with a single dose of diazepam 10 mg orally.
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Anesthesia and analgesia · Mar 2004
Randomized Controlled Trial Comparative Study Clinical TrialCombined spinal-epidural anesthesia using epidural volume extension leads to faster motor recovery after elective cesarean delivery: a prospective, randomized, double-blind study.
Epidural volume extension (EVE) via a combined spinal-epidural (CSE) technique is the enhancement of a small-dose intrathecal block by epidural saline boluses. In this prospective, randomized, double-blind study, we compared the EVE technique with single-shot spinal anesthesia with respect to its sensory and motor block profile and hemodynamic stability. Sixty-two parturients (n = 31 in each group) undergoing elective cesarean deliveries were administered either spinal anesthesia with hyperbaric 0.5% bupivacaine 9 mg and fentanyl 10 microg or CSE comprising intrathecal hyperbaric 0.5% bupivacaine 5 mg with fentanyl 10 microg, followed by 0.9% saline 6.0 mL through the epidural catheter 5 min thereafter. In each group, the lowest systolic blood pressure (SBP), sensory block level to loss of pain from pinprick, and modified Bromage scores were recorded at 2.5-min intervals. The visual analog pain score (VAS), peak sensory block height, highest modified Bromage motor score, time for sensory regression to the tenth thoracic dermatome (T10), and motor block recovery were compared between groups. Both groups were comparable in demographic data, VAS scores, peak sensory block height, time for sensory regression to T10, and lowest SBP recorded. Patients in the EVE group demonstrated significantly faster motor recovery to modified Bromage 0 (73 +/- 33 min versus 136 +/- 32 min, P < 0.05). ⋯ When compared with conventional, single-shot spinal anesthesia, epidural volume extension of a small-dose spinal block provides satisfactory anesthesia for cesarean delivery with only 55% of the bupivacaine dose required and is associated with faster motor recovery of the lower limbs.
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Anesthesia and analgesia · Mar 2004
Randomized Controlled Trial Comparative Study Clinical TrialNarcotrend index versus bispectral index as electroencephalogram measures of anesthetic drug effect during propofol anesthesia.
The Narcotrend monitor (MonitorTechnik, Bad Bramstedt, Germany) performs an automatic analysis of the electroencephalogram (EEG) during anesthesia based on a visual assessment of the raw EEG. Its newest software version 4.0 includes a dimensionless index that, similar to the bispectral index (BIS), ranges from 100 (awake) to 0. We compared the performance of Narcotrend index and BIS as EEG measures of anesthetic drug effect during propofol anesthesia. Eighteen adult patients scheduled for radical prostatectomy were investigated. An epidural catheter was placed in the lumbar space and electrodes for BIS (version XP; Aspect Medical Systems, Natick, MA) and Narcotrend were positioned as recommended by the manufacturers. Narcotrend index, BIS values, and propofol plasma and effect site concentrations as parallelly simulated by Rugloop software (Department of Anesthesia, Ghent University, Belgium) were automatically recorded in intervals of 5 s. Induction of anesthesia consisted of a fentanyl bolus and a propofol infusion. After endotracheal intubation, patients received 15 mL bupivacaine 0.5% epidurally, and 45 min later propofol dosages were subsequently increased and decreased twice. Simulated propofol effect site concentrations ranged from 2.0 +/- 0.4 microg/mL (smallest) to 6.3 +/- 1.3 microg/mL (largest) during these subsequent increases and decreases of propofol. In terms of prediction probability (P(K)) the performance of the Narcotrend index (P(K) = 0.88 +/- 0.03) to predict propofol effect site concentrations was comparable to the BIS (P(K) = 0.85 +/- 0.04). Using the respective EEG index as a measure of drug effect the mean k(e0) was calculated as 0.20 +/- 0.05 min(-1) for Narcotrend index and 0.16 +/- 0.07 min(-1) for BIS. In the observed propofol concentration range Narcotrend index detected differences in EEG dynamics as well as BIS. ⋯ This study in 18 adult patients undergoing radical prostatectomy describes the relationship between Narcotrend index and bispectral index versus predicted propofol effect compartment concentrations. In terms of prediction probability, the performance of the Narcotrend index and the bispectral index to predict propofol effect site concentrations was comparable.
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Anesthesia and analgesia · Mar 2004
Comparative StudyClinical evaluation of the effects of signal integrity and saturation on data availability and accuracy of Masimo SE and Nellcor N-395 oximeters in children.
Pulse oximetry manufacturers have introduced technologies that claim improved detection of hypoxemic events. Because improvements in signal processing and data rejection algorithms may differentially affect data reporting, we compared the data reporting and signal heuristic performance and agreement among the Nellcor N-395, Masimo SET, and GE Solar 8000 oximeters under a spectrum of conditions of signal integrity and arterial oxygen saturations. A blinded side-by-side comparison of technologies was performed in 27 patients, and data were analyzed for time of data availability, measures of agreement and signal heuristics, and warnings stratified by signal integrity and SpO(2). The Solar 8000 had less total data dropout than either of the new technologies. Masimo's LoSIQ (signal quality) heuristic rejected less data than Nellcor's MOT/PS (motion/pulse search) flag. When no signal heuristic was displayed, there was little difference in precision and bias between the two newer technologies; however, agreement between devices deteriorated in the presence of SIQ, MOT, or hypoxemia. Both newer devices flagged questionable data, but their use of different rejection algorithms resulted in different probabilities of presenting data. Therefore, with poor SIQ or during hypoxemia, the Nellcor N-395 and Masimo oximeters are not clinically equivalent to each other or to the older Solar 8000 oximeter. ⋯ We compared new pulse oximeters from Nellcor and Masimo and found that, with good signal conditions, both new devices performed similarly to older technology. Overall, Masimo reported less data as questionable than Nellcor. With poor signal conditions or during hypoxemia, the new devices are not clinically equivalent to each other or to the older technology.