Addition of ketamine to propofol for initiation of procedural anesthesia in children reduces propofol consumption and preserves hemodynamic stability.

BACKGROUND: There is no ideal anesthesia protocol to perform short invasive procedures in pediatric oncology. The combination of propofol and ketamine may offer advantages over propofol alone. METHODS: In a prospective, randomized, double-blind study, we analyzed 63 consecutive procedures performed in 47 oncology children. All patients received 1 mug/kg fentanyl, followed by propofol 1 mg/kg in group P (n=33) or propofol 0.5 mg/kg and ketamine 0.5 mg/kg in group PK (n=30) for the initiation of anesthesia. The need for supplementation with propofol and/or fentanyl to maintain an adequate level of anesthesia was recorded. The hemodynamic and respiratory profile, recovery time and the occurrence of side effects were compared. RESULTS: Significantly more children required propofol (100% vs. 83.3%) and fentanyl (75.5% vs. 43.3%) rescue doses, and developed hypotension (63.6% vs. 23.4%) and bradycardia (48.5 vs. 23.4%) in group P compared with group PK, with a comparable incidence of respiratory adverse events and recovery times. However, 40% of children in group PK were agitated following recovery compared with 6% in group P. CONCLUSIONS: The combination of propofol and ketamine for invasive procedures in pediatric oncology resulted in reduced propofol and fentanyl consumption and preserved hemodynamic stability, but more children in the combination group recovered with agitation.

Supplementation of pre-oxygenation in morbidly obese patients using nasopharyngeal oxygen insufflation.

During apnoea following induction of anaesthesia, morbidly obese patients may suffer a rapid decrease in oxygen saturation. This study compares pre-oxygenation alone with pre-oxygenation followed by nasopharyngeal oxygen insufflation on the onset of desaturation occurring during the subsequent apnoea. A randomised controlled trial was performed in 34 morbidly obese patients undergoing gastric bypass or gastric band surgery. Seventeen patients received nasopharyngeal oxygen supplementation following pre-oxygenation (Study group, body mass index = 41.8 (6.9) kg.m(-2)), and the other 17 patients received pre-oxygenation alone (Control group, body mass index = 42.7 (5.4) kg.m(-2)). Time from the onset of apnoea until S(p)o(2) fell to 95% was compared between the two groups with a cut-off of 4 min. In the control group, the S(p)o(2) fell from 100% to 95% during the subsequent apnoea in 145 (27) s, with a significantly negative correlation (r(2) = 0.66, p < 0.05) between the time to desaturation to 95% and the body mass index. In the study group, the S(p)o(2) was maintained in 16 of 17 patients at 100% for 4 min when apnoea was terminated. In conclusion, nasopharyngeal oxygen insufflation following pre-oxygenation in morbidly obese patients delays the onset of oxyhaemoglobin desaturation during the subsequent apnoea.