How Should We Sedate Children for CT Scans?

Posted: 03/11/2011 Question

What is the safest and most effective way to sedate a child for a head CT scan?
Response from Sergey M. Motov, MD Assistant Program Director, Department of Emergency Medicine, Maimonides Medical Center, Brooklyn, New York

Cooperation for diagnostic studies, such as CT, is a frequent indication for pediatric procedural sedation in the emergency department (ED).
ED physicians are armed with a variety of sedative agents, including chloral hydrate, pentobarbital, propofol, midazolam, and etomidate.
However, controversies exist with regard to the safest and most effective agent for procedural sedation in children who require a head CT scan. A review of the recent literature may help inform opinions.

A study by Mason and colleagues, appearing in the journal Radiology, compared the effectiveness and safety of oral pentobarbital and oral chloral hydrate for sedation in infants younger than 1 year of age during MRI and CT scans.
The results demonstrated that both medications were equally effective in providing successful sedation (50 mg/kg chloral hydrate and 4 mg/kg pentobarbital).
However, the overall adverse-event rate during sedation was lower with pentobarbital (0.5%) than with chloral hydrate (2.7%).

Moro-Sutherland and colleagues conducted a prospective, randomized clinical trial of 55 children undergoing head CT scans in the ED that compared the efficacy of sedation with intravenous (IV) midazolam with IV pentobarbital.
The results, published in the journal Academic Emergency Medicine, showed that 97% patients were successfully sedated and scanned in the pentobarbital group with mean dose of 3.75 mg/kg vs 19% of patients who were successfully scanned with midazolam alone. The study authors concluded that IV pentobarbital was more effective than IV midazolam for sedation of children requiring CT imaging.

Dr. Steven E. Zgleszewski led a prospective, observational study of 104 children who underwent sedation before CT scans at the Children's Hospital Boston, Harvard Medical School, Boston, Massachusetts. The researchers compared the incidence of adverse respiratory events and the recovery time of propofol sedation with similar data from a retrospective review of sedation with pentobarbital in patients who underwent CT imaging.

The results showed that patients sedated with propofol had more airway manipulation to relieve obstruction than the pentobarbital group (23% vs 0%), had more adverse respiratory events (12% vs 0%), but had faster recovery (34 minutes vs 100 minutes). The study authors concluded that sedation with propofol was associated with a greater incidence of adverse respiratory events.

In a prospective, randomized, double-blind trial of 61 patients between the ages of 6 months and 6 years, Kienstra and colleagues compared etomidate with pentobarbital for sedation in children for head and neck CT scans.The results demonstrated a 97% success rate with pentobarbital at a dose of 5 mg vs a 57% success rate with etomidate at a dose of 0.3 mg/kg. The study authors concluded that pentobarbital was more effective than etomidate for procedural sedation for head CT scans in children. However, the etomidate group had significantly shorter induction times, sedation times, and total examination times. Moreover, more parents of the children receiving etomidate reported that their children were at baseline at the time of discharge, and fewer parents in this group had concerns over their children's behavior after discharge.

Finally, a report by Baxter and colleagues for the Pediatric Sedation Research Consortium compared the efficacy, sedation duration, and adverse effects of etomidate and pentobarbital in 842 children undergoing head CT scans.
The study authors demonstrated that the etomidate group (446 patients) had 1 unsuccessful sedation vs 11 unsuccessful sedations in the pentobarbital group (336 patients); shorter sedation time (34 minutes vs 144 minutes); and less adverse effects, including oxygen desaturations, apnea, and prolonged recovery (0.9% vs 4.5%). They concluded that etomidate was more effective and efficient than pentobarbital for sedating children for head CT scans.

Conclusion

The cited literature demonstrated that pentobarbital performed better then chloral hydrate (less adverse effects), midazolam (better success rate), and propofol (less adverse effects). However, in a head-to-head comparison, etomidate outperformed pentobarbital with respect to successful sedations, shorter sedation time, and less adverse effects. Thus, etomidate is the safest and most effective sedative agent for children undergoing head CT scans.