Endotracheal tube cuff lidocaine is not superior to intravenous lidocaine in short pediatric surgeries.

BACKGROUND: Instillation of lidocaine into the endotracheal tube cuff is a method with reported efficiency in promoting a smoother emergence from anesthesia with endotracheal intubation. However, whether or not this method is helpful in children and in surgeries with short duration has not been investigated previously. METHODS: 176 ASA I-II children undergoing adenotonsillectomy were enrolled in this prospective, double-blind, randomized clinical trial. Patients were randomly allocated to two groups. Patients in the ECL group (n=88) were injected 2% lidocaine into their endotracheal tube cuff and received saline (1.5mg/kg) intravenously. The IVL group (n=88) received 1.5mg/kg of 2% lidocaine intravenously and saline into the endotracheal tube cuff. In both groups, intra-cuff injections were initiated immediately after insertion of the endotracheal tube and terminated before the cuff pressure reached 20 cmH(2)O. The parameters measured were: coughing (graded by a scale of 3 at the time of extubation), systolic and diastolic blood pressures and heart rate (from the time of extubation up to 5 min after extubation at 1-min intervals), and laryngospasm (defined as the presence of hoarseness or absence of airflow). RESULTS: The groups were not different in sex, age, weight, height, body mass index, anesthesia duration, and baseline hemodynamic parameters. The grade of coughing was significantly higher in the ECL group. The incidence of laryngospasm and hemodynamic trends did not differ between the groups. CONCLUSIONS: Our results indicate that intra-cuff lidocaine may not be beneficial in children and in surgeries with a short duration.

Effects of ephedrine on intubating conditions following priming with atracurium: a randomized clinical trial.

BACKGROUND: Priming is a well-known method to accelerate the onset of action of nondepolarizing neuromuscular-blocking agents. It consists of administration of a small dose of neuromuscular blocking agent several minutes before the principal dose is given. Ephedrine has been shown to improve the intubating conditions of rocuronium following its priming with a small dose. However, the potential effects of ephedrine on intubating conditions using atracurium after its priming with a small dose have not yet been studied. Since rocuronium is not available in Iran, atracurium is widely used as an alternative. METHODS: We studied two groups of patients, each group consisting of 32 patients. One group received ephedrine after priming (PE) and the other received placebo following priming (P). There were no significant differences between the two groups in age, sex, physical status (assessed using the American Society of Anesthesiologists classification), baseline mean arterial pressure and baseline heart rate. Patients with anticipated difficult airway, hypertension, obesity, any evidence of neuromuscular, cardiovascular, respiratory, hepatic, or renal disease, as well as those taking medications known to interact with atracurium or ephedrine were excluded. The anesthesiologist, the physician responsible for recording the results, and the statistician interpreting them were blinded to group allocations. Intubating conditions were graded according to Cooper's criteria. A clinically acceptable outcome was defined as good or excellent intubating conditions, represented by overall scores of 6-7 and 8-9, respectively. RESULTS: Intubating conditions were clinically acceptable in 22 patients in the PE group and 15 patients in the P group (p = 0.13). Vocal cord position and jaw relaxation scores during intubation and response to intubation did not differ significantly between the two groups. The mean arterial pressure showed significant differences over the course of time between the two groups (p < 0.01). Heart rate exceeded 120 bpm more frequently in the PE than in the P group (p < 0.01). CONCLUSION: The effects of ephedrine on improving intubating conditions following atracurium priming were not statistically significant. Given the risk of exacerbation of coronary ischemia by tachycardia, and the negative results on intubating conditions in our study, we cannot recommend the use of ephedrine for improving intubating conditions following priming with atracurium.