Anesthesia and analgesia
-
Anesthesia and analgesia · May 2000
Randomized Controlled Trial Comparative Study Clinical TrialDoes the addition of fentanyl to bupivacaine in caudal epidural block have an effect on the plasma level of catecholamines in children?
We evaluated the effect of adding fentanyl to bupivacaine, compared with bupivacaine alone, on the stress response. The effect was evaluated by determining blood levels of epinephrine (E) and norepinephrine (NE) in pediatric patients receiving caudal epidural blocks. Sixty children, 1-8 yr of age, scheduled for elective herniorrhaphy, were randomly allocated to two groups of 30 patients each. ⋯ There were no significant differences in the E and NE plasma levels between the two groups at H(0), H(1), and H(2) (P = 0.5, P = 0.12, P = 0.5, respectively). Pain scores (modified Children's Hospital of Eastern Ontario Pain Score) were also similar in both groups (P = 0. 19). This study suggests that adding fentanyl 1 microg/kg to bupivacaine in the caudal epidural block in children does not influence plasma levels of E and NE, nor does it improve the analgesic intensity of the caudal block.
-
Anesthesia and analgesia · May 2000
Randomized Controlled Trial Clinical TrialAlfentanil given immediately before the induction of anesthesia for elective cesarean delivery.
Opioids are routinely omitted at the induction of general anesthesia for cesarean delivery because of concerns about neonatal respiratory depression. The subsequent unmodified maternal stress response to tracheal intubation reduces placental perfusion. The short-acting opioid alfentanil may afford advantages at the induction, without subsequent neonatal depression. ⋯ One neonate in the alfentanil group required naloxone. The maternal stress response was attenuated in the alfentanil group but at the cost of early neonatal depression. However, all neonates should be monitored for possible immediate, but transient, respiratory depression.
-
Anesthesia and analgesia · May 2000
Randomized Controlled Trial Clinical TrialThe combined effect of age and premedication on the propofol requirements for induction by target-controlled infusion.
In this prospective study, we evaluated the combined influence of age and premedication on propofol requirements for the induction of anesthesia and their hemodynamic effects using a target-controlled infusion. We studied 180 patients separated into three age groups: 20-39 yr, 40-59 yr, and more than 59 yr. In each age group, patients were randomly allocated to receive either no premedication (n = 20), fentanyl (2 microg/kg) (n = 20), or midazolam (0.03 mg/kg) plus fentanyl (2 microg/kg) (n = 20). ⋯ The combined effect of the two factors was additive, but without significant interaction. The propofol requirements were significantly less in the midazolam-fentanyl groups, regardless of age, and among the premedicated patients older than 60 yr compared with the other age groups. We conclude that the combined effect of age and premedication on the requirements of propofol for the induction of anesthesia should be considered when the concentration is targeted with a target-controlled infusion system.
-
Anesthesia and analgesia · May 2000
Randomized Controlled Trial Clinical TrialThe onset time of rocuronium is slowed by esmolol and accelerated by ephedrine.
Administration of ephedrine prior to rocuronium decreases the onset time of neuromuscular blockade from rocuronium by 26%. This effect was attributed to a increased cardiac output. If so, beta adrenergic-blocking drugs, which decrease cardiac output, should prolong the onset time of rocuronium. ⋯ The onset time of rocuronium was significantly shorter after ephedrine (22%) and longer after esmolol (26%), as compared to placebo. No differences were observed among the three groups with regard to heart rate, systolic, diastolic or mean blood pressure. We concluded that a dose of 0.5 mg. kg(-1) of esmolol significantly prolongs the onset time of rocuronium with minimal hemodynamic changes.
-
Anesthesia and analgesia · May 2000
Randomized Controlled Trial Clinical TrialIntravenous chloroprocaine attenuates hemodynamic changes associated with direct laryngoscopy and tracheal intubation.
We compared the effects of an IV administration of chloroprocaine and lidocaine on circulatory responses associated with endotracheal intubation. Thirty patients were randomly allocated to receive normal saline (placebo), lidocaine (1.5 mg/kg), or preservative-free chloroprocaine (4.5 mg/kg) 45 s before endotracheal intubation. Blood pressures and heart rate and rhythm were recorded before laryngoscopy and at 0.5, 1, 1.5, 2, 3, and 5 min after intubation. ⋯ Measurable concentrations of chloroprocaine were recorded in plasma samples for 2 min after its administration. No adverse chloroprocaine effects (i.e., circulatory disturbances, venous irritation) were detected. The IV administration of chloroprocaine effectively blunted cardiovascular response produced by laryngoscopy and endotracheal intubation, and this effect was more pronounced when compared with IV lidocaine.