A clinical comparison of ketofol (ketamine and propofol admixture) versus propofol as an induction agent on quality of laryngeal mask airway insertion and hemodynamic stability in children.

BACKGROUND

In spite of being the preferred induction agent for LMA insertion, propofol has many undesirable side effects including dose-related cardiorespiratory depression and local pain at injection site. Ketofol as a novel induction agent has been introduced recently with comparable efficacy and improved hemodynamic control.

OBJECTIVE

To investigate ketofol as a suitable induction agent alternative to propofol for insertion of LMA in children considering insertion conditions, hemodynamic stability, local pain at injection site, and recovery.

MATERIALS AND METHODS

In this randomized, double-blind study, 100 children were randomly assigned into two groups of 50 patients each in which induction was performed with either propofol or ketofol. Providers were given one 20 ml syringe [represent either 2 mg/kg of propofol (P group) or 0.75 mg/kg of ketamine and 1.5 mg/kg of propofol (KP group)] and one 10 ml syringe for rescue if needed [represent 1 mg/kg of propofol (P group) or 0.25 mg/kg of ketamine and 0.5 mg/kg of propofol (KP group)]. After monitoring with bispectral index (BIS), general anesthesia was induced by infusion with a syringe perfuser at a constant rate of 250 ml/h with either of the two agents till the BIS values decreased to 40. Mean arterial pressure (MAP), heart rate (HR) were measured every 30 seconds up to 5 minutes after LMA placement. The time till BIS values decreased to 40 was measured. All children were evaluated for incidence of apnea, pain on injection, jaw relaxation, conditions for LMA insertion, and complications such as muscle rigidity, hallucinations, and excessive secretions.

RESULTS

Induction time (time to reach BIS of 40) was faster in the KP group (150 ± 23.5 seconds) than in the P group (205 ± 37.4 seconds). The incidence of injection pain was significantly lower in the KP group (10%) than in the P group (80%). Excellent jaw relaxation and full mouth opening were higher in the KP group [45 patients (90%)] than in the P group [38 patients (76%)]. Excellent LMA insertion conditions were observed in 45 patients (90%) in the KP group and 38 patients (76%) in the P group. The KP group showed preserved hemodynamic stability (mean blood pressure, heart rate) with less incidence and duration of apnea compared to the P group.

CONCLUSION

ketofol is a safe and effective alternative induction agent for LMA insertion in children with rapid onset of action and lower incidence of injection pain. It provided better LMA insertion conditions, improved hemodynamic stability with less prolonged apnea when compared with propofol.