Monsereenusorn, C., Rujkijyanont, P., & Traivaree, C. (2015). The clinical effect of fentanyl in comparison with ketamine in analgesic effect for oncology procedures in children: A randomized, double-blinded, crossover trial. Journal of the Medical Association of Thailand = Chotmaihet Thangphaet, 98, 358–364.

To compare the effects of fentanyl and ketamine as premedication before painful procedures in children

Participants scheduled for invasive procedures requiring sedation were randomized to receive either fentanyl or ketamine pre-medication before lumbar puncture for intrathecal chemotherapy or bone marrow biopsy. The treatment was reversed prior to the next procedure each child received. Pain was measured two hours after the procedure when patients fully recovered from sedation, and patients were monitored for 24 hours after the procedure. The average washout period was 5.8 weeks.

• N = 55   
• AGE = 16% were younger than 4, 43.6 % were 4–8 years, and 40% were older than 8
• MALES: 49.1%, FEMALES: 50.9%
• KEY DISEASE CHARACTERISTICS: All had hematologic cancers

• SITE: Single site   
• SETTING TYPE: Not specified    
• LOCATION: Thailand

• PHASE OF CARE: Multiple phases of care
• APPLICATIONS: Palliative care 

• Controlled, randomized, crossover trial

• FLACC scale (Faces, Legs, Activity, Cry, Consolability) for those younger than four years
• Wong-Baker FACES pain rating scale for 4–8 year olds
• Visual Analog Scale for Pain (VAS-Pain) for those older than eight years

Pain severity was lower with fentanyl (median 2 versus median 2.44 with ketamine) (p = 0.002). When receiving fentanyl, patients also had less nausea and vomiting post-procedure. Ketamine was associated with side effects of hallucination, nausea, vomiting, and increased salivation. Side effects seen with fentanyl were nausea (9%) and vomiting (3.64%) within 24 hours post-procedure.

Premedication with fentanyl in children prior to invasive procedures was associated with less severe pain and fewer side effects compared to ketamine.

It is unclear if the specific procedures were the same for both study conditions in the crossover. Validity of determination of side effects such as hallucination in the youngest children is questionable—behavioral changes were included in the author's definition of this side effect.

Fentanyl premedication for invasive procedures requiring sedation in children was associated with lower severity of pain after the procedures and fewer side effects compared to ketamine.