Remifentanil patient-controlled analgesia effect-site target-controlled infusion compared with morphine patient-controlled analgesia for treatment of acute pain after uterine artery embolization.

BACKGROUND: Post-procedural pain control after uterine artery embolization (UAE) of urethral leiomyomata remains a major problem. METHODS: This double-blind, randomized study tested the possibility to obtain a quicker onset of analgesia by using effect-compartment controlled remifentanil patient-controlled analgesia (remifentanil TCI-PCA) than by using i.v. morphine PCA. Both systems were connected to an i.v. catheter. Active drug or matching placebo administration was activated by a single push-button. Pain was assessed using a numerical rating scale (NRS) from 0 to 10. RESULTS: NRS values were lower in the remifentanil group (with a possible difference from two to seven points on the scale) during the initial 4 h post-embolization. After the fourth hour, the NRS values were identical between the groups. No major respiratory or haemodynamic side-effect was observed. CONCLUSIONS: Remifentanil PCA-TCI with a slow and progressive adapted algorithm without any associated premedication or co-medication is feasible in young healthy women undergoing UAE.

Transoral gastroplasty is safe, feasible, and induces significant weight loss in morbidly obese patients: results of the second human pilot study.

BACKGROUND AND STUDY AIMS: Bariatric surgical treatments have been proven to induce long-term weight loss in morbidly obese patients, but complications are relatively frequent. We recently reported a first human multicenter trial assessing the safety, feasibility, and weight loss results of the Transoral Gastroplasty (TOGA) system (Satiety Inc., Palo Alto, CA) at 6 months. Here we report the 6-month results of the second phase of the pilot trial with the TOGA system, with technical improvements to the device. PATIENTS AND METHODS: Patients met established criteria for bariatric surgery. The TOGA system, a set of transoral endoscopically guided staplers, was used to create a stapled restrictive pouch along the lesser curvature of the stomach. Follow-up was at 1 week and at 1, 3, and 6 months. At 3 months, re-treatment consisting in additional distal restrictions was allowed if necessary. RESULTS: Data were available for 11 patients in our center (7 female, mean age 44.2 years, mean body mass index 41.6). The procedure was completed safely in all patients. There were no serious adverse events. Mean excess weight loss was 19.2 %, 33.7 %, and 46.0 % at 1, 3, and 6 months, respectively. Average body mass index decreased from 41.6 before treatment to 33.1 at 6 months. Absolute mean weight loss was 9.9 kg, 17.5 kg, and 24.0 kg at 1, 3, and 6 months, respectively. A dramatic improvement in quality-of-life measures was observed in all patients. CONCLUSIONS: This second pilot trial confirmed the feasibility and safety of transoral gastroplasty. The early results and technical improvements reported in the present study are encouraging in terms of safety, early weight loss, and quality of life, and clearly allowed multicenter trials, which are planned to start soon.

[The anesthesiology-recovery department]. / Le Service d'Anesthésiologie Réanimation.

The Department of Anesthesiology and Reanimation is organised in units with clinical activities, which include the pre-operative care of patients, anesthesiological care and immediate post-operative supervision. Two post-operative treatment rooms also form part of the department. The main fields of research of the various units result from collaborations with other departments of Hôpital Erasme, in particular with regard to the development of advanced techniques or fit within the confines of the speciality.

Management of a ruptured basilar artery aneurysm during pregnancy.

A 36 year old woman who ruptured a basilar artery aneurysm at 38 weeks gestation in her second pregnancy was managed successfully by endovascular embolisation 36 hours after an emergency Caesarean section. The timing of treatment along with the obstetric, neurosurgical and anaesthetic aspects of this complex problem are discussed along with a review of the current literature on the subject.

Visual evaluation of residual curarization in anesthetized patients using one hundred-hertz, five-second tetanic stimulation at the adductor pollicis muscle.

UNLABELLED: We were looking for a clinical test to indicate a train-of-four (TOF) ratio of approximately 0.9. We compared the adductor pollicis muscle (AP) visually evaluated response to ulnar nerve 100-Hz, 5-s tetanus (RF100 Hz) with the measured AP TOF ratio in 30 ASA physical status I or II adult anesthetized (propofol, sufentanil, N2O/O2) patients. After the induction of anesthesia, the left ulnar nerve was stimulated at the wrist (single twitch and TOF) and the resultant isometric force was measured. When TOF was assessed, the independent investigators, unaware of the left AP-measured TOF ratios, visually evaluated the presence or absence of AP fading elicited by right ulnar nerve 100-Hz, 5-s tetanus. The 30 patients were randomly allocated to receive either 0.5 mg/kg atracurium (n = 15) or 0.1 mg/kg vecuronium (n = 15). The neuromuscular blockade was allowed to resolve spontaneously. A multiple logistic regression analysis was performed by computing the 771 visual observations. The probabilities of success of 100-Hz, 5-s tetanus to detect TOF ratios of 0.8, 0.85, and 0.9 were 99%, 96%, and 67%, respectively. The sensitivity and specificity of 100-Hz, 5-s tetanus as an indicator of TOF ratios of 0.85 and 0.9 are 100% and 75%, 54% and 67%, respectively. We conclude that RF100 Hz visual assessment seems to be highly sensitive in evaluating residual paralysis, as the absence of RF100 Hz visual fading at the AP is compatible with a TOF ratio > 0.85. IMPLICATIONS: After the administration of muscle relaxants, the absence of visual fading at the adductor pollicis, elicited in anesthetized patients by 100-Hz, 5-s tetanus, is compatible with a train-of four ratio > 0.85. Therefore, clinical observation of fading after 100-Hz, 5-s tetanus seems to be a highly sensitive test in evaluating residual paralysis.

Is recovery of neuromuscular transmission complete after the use of neostigmine to antagonize block produced by rocuronium, vecuronium, atracurium and pancuronium?

To test if recovery of neuromuscular transmission is complete after the use of neostigmine under standardized conditions, we have measured adductor pollicis mechanical activity in response to 0.1 Hz (twitch height), train-of-four (TOF) and 100 Hz (RF 100 Hz) ulnar nerve stimulations. We studied 56 adult anaesthetized (thiopentone, fentanyl, nitrous oxide in oxygen) patients, allocated randomly to one of four groups (n = 14) to receive rocuronium (group Roc), vecuronium (group Vec), atracurium (group Atr) or pancuronium (group Pan). Recovery of neuromuscular transmission was studied for 15 min after neostigmine 40 micrograms kg-1 was given at 25% recovery of twitch height. Fifteen minutes after antagonism, the TOF ratio was 0.91 (SEM 0.01), 0.88 (0.02) and 0.92 (0.01) (ns), and RF 100 Hz was 0.78 (0.01), 0.79 (0.02) and 0.78 (0.01) (ns) respectively, in patients in groups Roc, Vec and Atr, respectively. In patients in group Pan, TOF ratio and RF 100 Hz were only 0.76 (0.01) and 0.33 (0.04) respectively (P < 0.01, one-way analysis of variance, Duncan's multiple classification range tests). In contrast with pancuronium, antagonism of rocuronium-, vecuronium- and atracurium-induced neuromuscular blocks produced a similar high degree of recovery of neuromuscular transmission.

Conditions to optimise the reversal action of neostigmine upon a vecuronium-induced neuromuscular block.

BACKGROUND: Since neostigmine was introduced for reversal of neuromuscular block, there has been controversy about the optimum dose for antagonizing neuromuscular block. The purpose of this study was to characterise recovery of neuromuscular transmission following a vecuronium-induced block 15 min after neostigmine administration using different stimulation patterns, and to determine the effects of different doses of neostigmine given at various pre-reversal twitch heights. METHODS: Adductor pollicis (AP) mechanical activity in response to low (0.1 and 2 Hz) and high (50 and 100 Hz) frequency stimulation, was recorded 15 min after 20, 40 and 80 micrograms/kg neostigmine, given to reverse a vecuronium-induced block at 10, 25 and 50% pre-reversal twitch height (TH). Fifty four ASA class I and II anaesthetised (methohexital, fentanyl, N2O/O2) young adult patients were studied and randomly allocated into 9 groups of 6 patients each. RESULTS: In contrast to twitch height (TH) and residual force after 50 Hz, 5 s tetanic stimulation (RF50Hz), the greater sensitivity of train-of-four (TOF) ratio and residual force after 100 Hz, 5 s tetanic stimulation (RF100Hz) points out the best reversal conditions (prereversal TH and the optimal neostigmine dose) (P < 0.001, two-way analysis of variance). The highest reversal scores (about 0.9 TOF ratio and RF100Hz) were obtained when 40 micrograms/kg of neostigmine was given at 25 and 50% TH. A 0.9 TOF ratio was also observed when 40 micrograms/kg of neostigmine was given at 10% TH, but, under these conditions, RF100Hz was only 0.6 (P < 0.05, Duncan test). CONCLUSION: To optimise the reversal action of neostigmine in order to obtain the highest neuromuscular transmission recovery (0.9 TOF ratio and RF100Hz) during a vecuronium-induced neuromuscular block, the 40 micrograms/kg dose has to be given at 25 to 50% recovery of TH.

Influence and relative sensitivities of 50-Hz and 100-Hz tetanic stimuli on subsequent tetanic fade ratios in patients receiving vecuronium.

We studied the possible effects of repetitive (1-min interval) 50- and 100-Hz tetanic stimuli on 50-Hz and 100-Hz tetanic fade ratios (RF50HZ and RF100HZ). We also evaluated the sensitivity of the recorded responses to these two tests to assess residual neuromuscular block (isometric adductor pollicis mechanical activity), either during spontaneous recovery, or 15 min after neostigmine administration, in 22 adult anesthetized (thiopental, fentanyl, N2O/O2) patients receiving vecuronium. Two 50-Hz and two 100-Hz, 5-s duration, tetanic stimulations were randomly assessed at 1-min intervals: in a spontaneous (SPO) group (n = 11), when train-of-four (TOF) ratio spontaneously regained 0.7, and in a neostigmine (NEO) group (n = 11), 15 min after 40 micrograms/kg neostigmine was given intravenously at 25% return of control twitch tension. In the SPO group, when TOF ratio was 0.7, RF50HZ was 0.92 +/- 0.01 before and after subsequent tetanic stimulation, while RF100HZ was 0.48 +/- 0.05 and 0.47 +/- 0.05, respectively (not significant [NS]). In the NEO group, when TOF ratio was approximately 0.9, RF50HZ was 0.93 +/- 0.01 before and after subsequent tetanic stimulation, while RF100HZ was 0.80 +/- 0.02 and 0.78 +/- 0.02, respectively (NS). From patient to patient, both RF50HZ and RF100HZ were also identical. In conclusion, in patients receiving vecuronium, 1) 5-s, 50- and 100-Hz tetanic stimuli may be repeated without changes at 1-min intervals and, 2) in contrast to RF50HZ, recorded RF100HZ enables one to determine residual neuromuscular block during spontaneous recovery (P < 0.001) such as after neostigmine reversal (P < 0.05).

Low and high frequency stimulation tests to characterize the effects of edrophonium on vecuronium-induced neuromuscular block.

We recorded adductor pollicis mechanical activity in response to low (0.1 and 2 Hz) and high (50 and 100 Hz) frequency stimulation 15 min after edrophonium 250, 500 and 1000 micrograms kg-1, given to antagonize vecuronium-induced block at 10, 25 and 50% pre-reversal twitch height. We studied 54 ASA class I and II anaesthetized (methohexitone, fentanyl, nitrous oxide) young adult patients allocated randomly to nine groups of six patients each. The greater sensitivity of train-of four (TOF) ratio and residual force after 100-Hz, 5-s tetanic stimulation (RF100) to residual deficit allowed discrimination more readily between the effects of edrophonium dose and pre-reversal twitch height (P < 0.001, two-way analysis of variance). The highest reversal scores (approximately 0.9 TOF ratio and 0.6 RF100) were obtained when edrophonium 500-1000 mg kg-1 was given at 50% twitch height (P < 0.05, Duncan's test).

Comparison of neostigmine-induced recovery with spontaneous recovery from mivacurium-induced neuromuscular block.

In 24 ASA I-II adults anaesthetized with thiopentone, fentanyl and nitrous oxide in oxygen, we studied neuromuscular transmission with isometric adductor pollicis monitoring. Patients received mivacurium 0.2 mg kg-1 followed by an infusion lasting at least 60 min and adjusted to maintain twitch height at 1-5%. After termination of the mivacurium infusion, when twitch height spontaneously regained 25% of its control value, the patients were allocated to two groups of 12 patients each. In group NEO patients received neostigmine 40 micrograms kg-1 and atropine 15 micrograms kg-1 and in group SPO neuromuscular transmission was allowed to recover spontaneously. Twitch height was measured every 10 s and train-of-four (TOF) (2 Hz) every 3 min. After 15 min, residual force after tetanic stimulation (50 and 100 Hz, 5-s duration (RF50HZ, RF100HZ), 1 min apart) were recorded sequentially. At 15 min, mean TOF ratio was greater in group NEO (0.94 (SEM 0.01)) than in group SPO (0.87 (0.02)) (P < 0.01). All patients in group NEO recovered to a TOF ratio greater than 0.7 after 6 min compared with 15 min in group SPO (P < 0.005). A TOF ratio greater than 0.9 was observed in all patients in group NEO compared with only six in group SPO (P < 0.025). Nevertheless, RF50HZ and RF100HZ did not differ significantly (0.92 (0.01) (group NEO), 0.91 (0.01) (group SPO) and 0.83 (0.02) (group NEO), 0.78 (0.03) (group SPO), respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

The influence of atropine dose on recovery from vecuronium-induced neuromuscular blockade.

To determine whether the dose of atropine affects the rate of neostigmine-induced recovery from vecuronium-induced neuromuscular blockade, the authors monitored isometric adductor pollicis mechanical activity in 36 anesthetized (thiopental, fentanyl, nitrous oxide) adult patients (ASA physical status 1 or 2). Once surgery was completed and twitch height had spontaneously regained 25% of its initial value, the patients were randomly allocated into three groups (A10, A15, A20; n = 12 in each group) according to the dose of atropine (10, 15, or 20 micrograms/kg) that was mixed with 40 micrograms/kg neostigmine. Twitch height, train-of-four, and 50- and 100-Hz tetanic fade were recorded for 15 min after the administration of the reversal agents. No significant differences were found among the three groups in the final twitch height (95% +/- 2%), train-of-four (87% +/- 1%, 88% +/- 2%, 89% +/- 1%), and 50-Hz tetanic fade (90% +/- 1%, 94% +/- 1%, 93% +/- 1%) (mean +/- SEM). Fifteen minutes after reversal, fade in response to 100-Hz tetanus was statistically greater in the A10 group than in the two other groups (70% +/- 3% of control versus 84% +/- 4% and 81% +/- 2%) (mean +/- SEM, P less than 0.05). The present results demonstrate that larger doses of atropine facilitate neostigmine's reversal of vecuronium neuromuscular blockade. The clinical implications of the differences observed in this study remain to be determined.

Effects of residual concentrations of isoflurane on the reversal of vecuronium-induced neuromuscular blockade.

Thirty-six anesthetized patients (ASA physical status 1 or 2) undergoing elective surgery were monitored (isometric adductor pollicis mechanical activity) to detect the effects of discontinuing isoflurane anesthesia upon the reversal of vecuronium-induced neuromuscular blockade. Neuromuscular blockade was produced by vecuronium 100 micrograms/kg and additional doses of 20 micrograms/kg until completion of surgery. The patients were randomly divided into three groups: in the control group (n = 12), only fentanyl/N2O was given; in the "isostable" group (n = 12), isoflurane at an end-tidal concentration of 1.25% was maintained throughout anesthesia; in the "isostop" group (n = 12), isoflurane 1.25% was discontinued before neostigmine administration. In all groups, paralysis was antagonized with 15 micrograms/kg intravenous (iv) atropine and 40 micrograms/kg iv neostigmine when the twitch height (0.1 Hz) had regained 25% of its control value. The measured parameters were twitch height, train-of-four, and 50--100-Hz tetanic fade. No significant differences were found among the three groups with respect to the final twitch heights and tetanic fades at 50 Hz. In the isostable group, final mean train-of-four was significantly less (75%) than in the other patients (88%) (P less than 0.01). Mean tetanic fade at 100 Hz was significantly less in the isostable group (31%) than in the isostop group (57%) (P less than 0.01) and control group (84%) (P less than 0.01). We conclude that discontinuing isoflurane anesthesia for 15 min improves the reversal of a vecuronium paralysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Impairment of the antagonism of vecuronium-induced paralysis and intra-operative disopyramide administration.

A 63-year-old male was admitted to hospital for a cholecystectomy, vagotomy and gastro-enterostomy. Muscle paralysis was induced with 70 micrograms/kg vecuronium, followed by increments of 20 micrograms/kg when the initial twitch height returned to 25% of control. The patient received 3 doses of 10 mg disopyramide intravenously, on account of supraventricular ectopic beats, followed by an infusion of 25 mg/hour. Paralysis was reversed using 0.75 mg atropine and 2.5 mg neostigmine once the twitch height had returned spontaneously to 25% of its initial value. Fifteen minutes later, twitch height had returned to control value and the train-of-four was above 85%, but the responses to tetanic stimulation at 100 Hz and 50 Hz remained severely depressed (10% and 45%, respectively). The patient's trachea was extubated after 20 minutes, but residual fade was still observed. This impairment of neuromuscular transmission, detected only with high frequency stimulation, was present with a measured concomitant plasma level of disopyramide of 5.1 micrograms/ml.

[Spontaneous development of paralysis induced by equipotent doses of vecuronium, atracurium, fazadinium, pancuronium, gallamine and d-tubocurarine]. / Evolution spontanée de la paralysie obtenue par des doses équipotentes de vécuronium, atracurium, fazadinium, pancuronium, gallamine et d-tubocurarine.

Thirty-six patients undergoing elective surgery were studied after obtaining their informed consent. They were randomly assigned to six series of six patients each. One hour before anaesthesia, all patients received 0.2 mg.kg-1 diazepam orally. After induction of anaesthesia with 1-1.5 mg.kg-1 methohexitone and 5 micrograms.kg-1 fentanyl, the patients were paralysed and ventilation was controlled manually (semi-open circuit; 50% N2O/50% O2). Each patient received a single dose of either 70 micrograms.kg-1 fazadinium, 70 micrograms.kg-1 pancuronium, 2,500 micrograms.kg-1 gallamine or 450 micrograms.kg-1 d-tubocurarine. Neuromuscular function was monitored by measuring the isometric contraction of the adductor pollicis muscle in response to supramaximal stimulations of the ulnar nerve at the wrist (square wave pulse of 0.2 ms duration at supramaximal intensity delivery at 0.1 Hz). Three parameters were measured: the time between the injection of the relaxant drug and recovery of the twitch height at 50% of its baseline (RT0-50); the time between the injection of the relaxant drug and recovery of the twitch height at 90% of its baseline (RT0-90); the time between the injection of the relaxant drug and recovery of the twitch height from 25 to 75% of its baseline (RT25-75). The values of the observed parameters were expressed in minutes (means +/- SEM).(ABSTRACT TRUNCATED AT 250 WORDS)

Evolution of vecuronium requirements for stable mechanical effect: comparison with or without previous succinylcholine administration.

To evaluate possible interactions between residual succinylcholine and vecuronium, the amount of vecuronium required to maintain the twitch height (TH) at 10% of its initial value was measured over a 90-min period by the on-demand infusion method in two series of 15 adult patients (ASA class I-II). One group, the vecuronium treatment (V) group, received 70 micrograms X kg-1 of vecuronium and the on-demand infusion. The second group, the succinylcholine-vecuronium treatment group (SV), was given 30 micrograms X kg-1 of vecuronium and on-demand infusion 5 min after the complete recovery of TH after administration of 1 mg X kg-1 of succinylcholine. During the first 10 min, the amount of vecuronium required to maintain TH at 10% of its control was significantly greater in the group given V than in the group given SV, 15122 +/- 856 (mean +/- SEM) vs 9851 +/- 486 micrograms X m-2 X hr-1 (P less than 0.001). Thereafter, the amount of vecuronium required to maintain TH at 10% of control was similar: 2808 +/- 275 and 3068 +/- 206 micrograms X m-2 X hr-1. When the infusion of vecuronium was stopped after 90 min, the time required for spontaneous recovery from 25 to 75% of control TH levels was similar: 20.1 +/- 3.3 min in the group given V and 18.9 +/- 2.5 min in the group given SV (not significant). We conclude that after a vecuronium on-demand infusion of long duration (lasting more than 90 min), previous succinylcholine administration does not interfere with late vecuronium requirements and the spontaneous rate of recovery of TH.

[Atracurium in the elderly subject]. / L'atracurium chez le sujet âgé.

The effects of age on the pharmacodynamics of atracurium have been studied in twenty-four consenting adult patients undergoing elective surgery. They were divided in three groups according to their age (mean +/- SEM): group 1 (n = 8; 26 +/- 3 yr), group 2 (n = 8; 53 +/- 2 yr) and group 3 (n = 8; 76 +/- 2 yr). Anaesthesia was induced with methohexitone (1 mg . kg-1) and fentanyl (5 micrograms . kg-1), and maintained with 66% N2O plus fentanyl on demand. Ventilation was controlled and adjusted to produce normocapnia. The isometric contraction of the adductor pollicis muscle in response to supramaximal cubital nerve stimulation delivered at 0.1 Hz was measured with a force displacement transducer. A loading dose of atracurium (0.3 mg . kg-1) was given before tracheal intubation. Thereafter, twitch height (TH) was maintained at 10% of its baseline reading by adjusting the flow of a Harvard syringe containing 0.5 mg . ml-1 of atracurium in saline. The amount of atracurium required to maintain a stable twitch height, calculated for a 60 min period, was 14.7 +/- 1 mg . m-2 . h-1 for group 1, 13.6 +/- 1.5 mg . m-2 . BSA-1 for group 2 and 15 +/- 2.1 mg . m-2 . BSA-1 for group 3. At the end of the infusion period, the TH25-75 recovery rates were not statistically different in the three groups: 15.4 +/- 1.9 min for group 1, 14.8 +/- 1.1 min for group 2 and 14.5 +/- 1.6 min for group 3.(ABSTRACT TRUNCATED AT 250 WORDS)