[Risk of secondary neuromuscular blockade after autotransfusion of blood drawn from the patient following curare administration]. / Risque de curarisation secondaire après autotransfusion de sang prélevé chez un patient curarisé.

A secondary neuromuscular blockade can occur after transfusion of autologous blood withdrawn after injection of muscle relaxants. In this study time course of muscle relaxation after transfusion of blood withdrawn before or after administration of atracurium (A) or vecuronium (V) was assessed. Forty adults undergoing haemorrhagic urologic surgery were included in the study. After induction of general anaesthesia and intubation of the trachea facilitated by local lidocaine, they were divided into 4 groups. In groups A1 and V1 the blood units were withdrawn before injection of atracurium 0.5 mg.kg-1 or vecuronium 0.1 mg.kg-1. In group A2 and V2 the blood units were withdrawn after administration of muscle relaxants. Haematocrit was decreased to 0.30. The last bolus of these muscle relaxant was injected 30 min before the end of surgical procedure. Autologous blood was transfused when train of four (T4R) recovered to 0.80. Electromyographic elicited responses to T4R stimulation were obtained every minute during the 4 first minutes after the beginning of transfusion (T1 to T4), thereafter every minute during the 5 first minutes after the end of transfusion (T5 to T9), and finally every 5 minutes for 10 minutes (T10 and T11). There was a secondary neuromuscular blockade in patients of groups A2 and V2. The intensity of blockade was more important after vecuronium than after atracurium (p < 0.01 from T2 to T11 between groups A2 and V2). In group A2, the T4R had not reached the control level at the end of the procedure (0.78 at T11 vs 0.80 at T0). These data emphasize the importance of withdrawing blood units before administration of muscle relaxants.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacodynamics of vecuronium in patients with and without renal failure: a meta-analysis.

Eight trials comparing the effects of vecuronium in patients with either normal renal function or renal failure were subjected to a meta-analysis. Vecuronium doses were similar in the different trials, identical in the two patient groups of any given trial, and ranged from 0.05 to 0.14 mg.kg-1. Neuromuscular blockade was assessed by TOF or single twitch stimulation, and recorded by either mechanomyography or electromyography. Indices of blockade included onset time (from injection to maximal twitch depression), duration of action (from injection to recovery to 25% of control twitch) and 25-75% recovery index. Statistical analysis used Hedges method: effect size and variance were calculated for each relevant outcome, then the global effect size was estimated by pooling the effect sizes of each trial. Three separate meta-analyses were conducted. No differences were found either in onset time, or in recovery index between the two groups, whereas the duration of action was longer in the renal failure group. It is concluded that renal function is likely involved in the pharmacokinetic parameters of vecuronium.

[Acute nicardipine poisoning]. / Intoxication aiguë par la nicardipine.

A 41 year old man with overdose of nicardipine is reported. Quickly after the poisoning, he developed a cardiovascular collapse picture with renal failure and myocardium ischemia. The clinical picture improved with injection of dobutamine and dopamine. The hemodynamic study showed a fall of the systemic resistances. The recovery was complete 40 hours after the ingestion.

[Does flumazenil, a benzodiazepine antagonist used during the anesthesia recovery period, have an anxiogenic effect?]. / Le flumazénil, antagoniste des benzodiazépines, utilisé lors du réveil anesthésique, a-t-il un effet anxiogène?

The goal of this study was to assess the degree of postoperative anxiety flumazenil might provide in patients when used to reverse the sedation induced by midazolam. Twenty-four patients, aged 18 to 60 yrs, and scheduled for elective orthopaedic surgery of the upper limb, were included in the study Regional anaesthesia (brachial plexus block) was carried out 20 min after the patient had been premedicated with 0.15 mg.kg-1 intramuscular midazolam. When the block was clinically complete, 0.12 mg.kg-1 midazolam was given intravenously. Sedation was maintained throughout surgery using 0.03 mg.kg-1 midazolam every quarter of an hour (mean total dose 0.206 mg.kg-1). At the end of the procedure, the patients were randomly allocated to one of two groups: A+, the patients were given 0.1 mg intravenous flumazenil repeated every min until the patient was fully awake (mean 4.5 +/- 2.6 micrograms.kg-1); and A-, the patients were allowed to recover spontaneously. A wakefulness, and a determination just before premedication (E1, P1, H1 respectively). The degree of recovery was assessed in both groups, and, when the value of the wakefulness test had returned to that of E1 (E2) (E2 = E1), P2 and H2 were carried out. There were no statistically significant differences between P1 and P2, and between H1 and H2, and this for either group of patients. So, the doses of flumazenil used, which awoke all the patients within 3 min, did not create any anxiety. In accordance with most of the recently published studies, flumazenil can be safely used to reverse benzodiazepine induced sedation.

[Comparison of propofol and propanidid administered at a constant rate]. / Comparaison du propofol au propanidide administrés à débit constant.

So as to compare the anaesthesia obtained using propofol with that obtained using propanidid, 40 ASA I patients, aged between 18 and 50 years, who were to undergo elective orthopaedic or plastic surgery lasting more than 60 min, were randomly divided into two equal groups, one receiving propofol (PF) and the other propanidid (PD). All the patients received 0.5 mg atropine, 100 mg pethidine and 7.5 mg droperidol (10 mg if weight greater than 60 kg) intramuscularly 45 min before induction. Patients in group PF were then given 2 mg.kg-1 propofol over 1 min and 0.9 microgram.kg-1 fentanyl over 3 min, followed by a constant rate infusion of 5 mg.kg-1.h-1 propofol and 3 micrograms.kg-1.h-1 fentanyl. For PD patients, the doses of fentanyl were identical; they were given 10.6 mg.kg-1 propanidid over 3 min for induction, and 37 mg.kg-1.h-1 for maintenance. All the patients were intubated and ventilated mechanically. The usual anaesthetic parameters were monitored at induction, during surgery, and during recovery. Consciousness was lost more quickly with propofol (p less than 0.05), but the corneal reflex returned more rapidly in group PD (p less than 0.02). The time required for a full return to normal consciousness was identical in both groups. The fall, during induction, and the increase, during recovery, of Pasys were greater in group PD (p less than 0.05 and less than 0.001 respectively). Padia and heart rate were lower in group PF after the 30th min (p less than 0.05 and less than 0.01 respectively).(ABSTRACT TRUNCATED AT 250 WORDS)