In mechanically ventilated adults with septic shock, a single bolus of ketamine (1 mg/kg) increased cardiac output, stroke volume, heart rate, and mean arterial pressure, whereas a bolus of fentanyl (1 mcg/kg) decreased these measures. Six minutes after injection, cardiac output rose by a median of 71% in the ketamine group and fell by a median of 31% in the fentanyl group. Ketamine bolus was associated with higher cardiac output and stroke volume compared to fentanyl bolus.
In children aged 1 to 7 years undergoing laparoscopic surgery, a single dose of either 1 μg/kg dexmedetomidine or 0.3 mg/kg esketamine given at the end of carbon dioxide pneumoperitoneum reduces the incidence of emergence agitation compared to saline. Emergence agitation occurred in 8.8% of the dexmedetomidine group and 11.8% of the esketamine group, versus 35.5% with saline. Recovery time and extubation time were longer with dexmedetomidine (about 41 and 43 minutes) than with saline (about 33 minutes for both), but time in the post-anesthesia care unit did not differ significantly among the groups.