[Comparative study of the efficacy and tolerance of propofol and thiopental in induction and in continuous perfusion with neuroleptanesthesia]. / Estudio comparativo de eficacia y tolerancia de propofol con tiopental en la inducción y en perfusión continua con la neuroleptoanestesia.

We have studied 40 ASA I/II patients aged from 18 to 65 years undergoing otorhinolaryngologic surgery of 40-100 minutes of duration. Patients were randomly assigned to two groups. Anesthesia in group I was induced with thiopental, 4 mg/kg and maintained with N2O at 66% and a variable perfusion of fentanyl. In group II, anesthesia was induced with propofol, 2.5 mg/kg and maintained with a perfusion of 6-12 mg/kg/hour and an initial perfusion of fentanyl, 4 micrograms/kg/hour. Loss of consciousness occurred in 37.49 +/- 9.78 seconds in group I and in 46.25 +/- 12.62 seconds in group II, with no significant differences. Two minutes after induction, propofol group presented a significant decrease in systolic blood pressure of - 12 mm Hg and both groups presented comparable increases in systolic blood pressure and heart rate during intubation. Five minutes later, systolic blood pressure regained normal values. Maintenance in group II was achieved in a proper fashion with a mean propofol consumption of 9.5 +/- 2.6 mg/kg/hour and fentanyl consumption of 4.94 +/- 2.22 micrograms/kg/hour whereas in group II, with N2O at 66%, the amount of fentanyl required was 6.85 +/- 2.95 micrograms/kg/hour, which was significantly higher. Eye opening from the time of interruption of anesthetics was achieved at 6.6 +/- 3.2 minutes in group I and 12.44 +/- 6.34 in group II. Consciousness was regained at 11.25 +/- 3.96 and 16.87 +/- 6.95 minutes, respectively. Pain on injection occurred in 15% with propofol and in 10% with thiopental. No patient presented major complications nor phlebitis after administration of the anesthetic.

[Evaluation of the degree of muscle blockade: a comparative study using electromyography of the muscular relaxation induced by pancuronium, atracurium and vecuronium]. / Evaluación del grado de bloqueo muscular: estudio comparativo mediante electromiografía de la relajación muscular provocada por el pancuronio, atracurio y vecuronio.

To compare the muscle relaxing effect of pancuronium, atracurium and vecuronium, 99 patients operated on under neuroleptanesthesia were divided in three groups depending on whether they had received, during induction, pancuronium 0.1 mg/kg, atracurium 0.5 mg/kg, or vecuronium 0.1 mg/kg. One-fourth of the initial dose was repeated if necessary. The electromyographic study of the muscle relaxing effect was carried out with stimulation of the cubital nerve with courses of supramaximal square wave electric stimuli in 'trains of four'. The time to maximal blockade (TMB), the time of clinical effectiveness (TCE), the total duration time (TDT), the time of duration of the maintenance dose (DM 25) and the recovery index (RI) were measured. TMB was 4.3 +/- 1 min for pancuronium, 3.5 +/- 0.8 min for atracurium, and 3.3 +/- 0.98 min for vecuronium. The differences between pancuronium and the other drugs were statistically significant, but they were not so between the latter two. TCE was 67.9 +/- 13.5 min for pancuronium, significantly longer than with vecuronium and atracurium (28.2 +/- 5.7 and 31.5 +/- 4.7, respectively). TDT was 126.2 +/- 19.9 min for pancuronium, 61.2 +/- 11.5 min for atracurium and 55.5 +/- 16.7 for vecuronium. The mean duration of the repeated dose was 52.7 +/- 8.4 min for pancuronium, 19.9 +/- 5 min for vecuronium and 10.9 +/- 5 min for atracurium. RI, which was similar for atracurium and vecuronium (12.7 +/- 1.7 min and 12.8 +/- 3.3 min), was longer for pancuronium (27.7 +/- 4.3 min).