Search

Background: Inhalation anesthesia is a frequently used method for anesthesia induction, especially in young children. No information is available on the optimum time for safe intravenous cannulation after inhalational induction in children with dexmedetomidine premedication. The purpose of the present study was to determine the optimal time for intravenous cannulation after induction of anesthesia with sevoflurane and nitrous oxide in children premedicated with intranasal dexmedetomidine., Methods: This prospective and observational study was conducted by using the up-down sequential method. Children, who were aged 2-6 years with ASA physical status I, and who underwent inhalation induction for elective surgery were included in the study. Anesthesia was induced with sevoflurane and nitrous oxide after the premedication with intranasal dexmedetomidine (2 mcg/kg). Intravenous cannulation was attempted on the dorsum of the hand by an experienced anesthesiologist 4 min after the loss of the eyelash reflex in the first patient. The procedure was considered successful in patients without any movement, cough, or laryngospasm. The waiting time for cannulation was increased by 15 s if the procedure was not successful in the previous patient, and on the contrary, it was reduced by 15 s if the procedure was successful in the previous patient. The probit test was used in the analysis of up-down sequences., Results: In the present study in which a total of 40 patients were included, the effective cannulation time was found to be 14.40 s (95% confidence limits, 1.30-27.82 s) in 50% of the patients, and the effective cannulation time was found as 84.64 s (95% confidence limits, 69.61-218.26 s) in 95% of the patients., Conclusions: In conclusion, we suggest that the appropriate time for cannulation is 85 s (1.45 min) after the loss of eyelash reflex in children sedated with dexmedetomidine and induction with sevoflurane and nitrous oxide-oxygen mixture., (© 2022 Acta Anaesthesiologica Scandinavica Foundation.)

Background: This study was designed to evaluate the effect of dexmedetomidine on the acute hyperdynamic response, duration of seizure activity and recovery times in patients undergoing electroconvulsive therapy (ECT)., Methods: Fourteen patients underwent a total of 84 ECT sessions as a crossover design. Patients were randomly allocated to receive either dexmedetomidine (1 mug/kg IV over a period of 10 min) or saline (control). Anaesthesia was induced with propofol 1 mg/kg, and then succinylcholine 0.5 mg/kg IV was administered. Arterial blood pressure and heart rate (HR) were recorded during the study period., Results: HR in the dexmedetomidine group was lower than that in the control group at 5 and 10 min after the start of study drug infusion, and at 1, 3 and 10 min after the seizure ended (P<0.05). Peak HR was lower in the dexmedetomidine group compared with that in the control group (P<0.05). The mean arterial pressure (MAP) values in the dexmedetomidine group were lower at 0, 1, 3 and 10 min after the seizure ended compared with the control group (P<0.05). Both motor and electroencephalography (EEG) seizure duration in the control group (35.65 +/- 14.89 and 49.07 +/- 9.94 s, respectively) were similar to that in the dexmedetomidine group (33.30 +/- 12.01 and 45.15 +/- 17.79 s, respectively) (P>0.05). Time to spontaneous breathing, eye opening and obeying commands were not different between the groups., Conclusion: A dexmedetomidine dose of 1 mug/kg IV administered over 10 min before the induction of anaesthesia with propofol may be useful in preventing the acute hyperdynamic responses to ECT without altering the duration of seizure activity and recovery time.

Background: The aim of this study was to investigate the effects of pre-operative dexmedetomidine infusion on hemodynamics in patients with pulmonary hypertension undergoing mitral valve replacement surgery., Methods: Patients were randomly divided into placebo (group P, n= 16) and dexmedetomidine (group D, n= 16) groups. In group D, a 1 microg/kg bolus dose of dexmedetomidine was administered 10 min before the induction of anesthesia, followed by a 0.4 microg/kg/h infusion until the surgical incision. Anesthesia was induced with lidocaine (1 mg/kg), midazolam (0.2 mg/kg) and fentanyl (5 microg/kg) in both groups. Anesthesia was maintained with 0.5% isoflurane and fentanyl depending on the hemodynamic situation. The hemodynamic values during the investigation were obtained., Results: In group D, the mean arterial pressure (MAP), mean pulmonary arterial pressure (MPAP) and pulmonary capillary wedge pressure (PCWP) were decreased effectively in comparison with the values in the placebo group (P < 0.05), and there was an attenuation in the increase in the systemic vascular resistance index (SVRI) and pulmonary vascular resistance index (PVRI) at the post-sternotomy period., Conclusions: The pre-operative administration of the alpha(2)-agonist dexmedetomidine decreases the fentanyl requirement and attenuates the increase in SVRI and PVRI at the post-sternotomy period relative to the baseline levels, and decreases effectively MAP, MPAP and PCWP in comparison with the values in the placebo group, in patients with pulmonary hypertension undergoing mitral valve replacement surgery.