PEDIATRICS Vol. 108 No. 3 September 2001, pp. 817-817

Concerns/Questions About Sedation and Computed Tomography Scans

To the Editor.

We offer our comments regarding the article "Rectal Methohexital Sedation for Computed Tomography Imaging of Stable Pediatric Emergency Department Patients" published in Pediatrics.¹

In the "Methods" section, the exclusion criteria include patients with altered mental status. However, in the "Results" section we read that "the most common indication for computed tomography (CT) scanning was closed head injury, but others included mental status changes."

Significant hypoventilation requiring bag-valve mask ventilation occurred in 3% of patients in this study. In an earlier prospective study by Audenaert et al,² about 4% of 434 children experienced significant airway obstruction and/or desaturation after rectal methohexital. Two other patients required aggressive airway intervention (positive pressure ventilation, oropharyngeal airway and/or intubation).

We are concerned about the use of a technique which causes "a significant amount of transient respiratory depression" (as stated by the authors) in children with undiagnosed head injuries, particularly without vascular access. Hypoventilation and hypercarbia in patients with closed head injuries and mental status changes could have deleterious effects on intracranial pressure.

Another concern is the risk of aspiration. American Academy of Pediatrics guidelines call for fasting before deep sedation in children.³ It is likely that many patients presenting to the emergency department with trauma would not be fasted. Trauma further delays gastric emptying in children,⁴ making it impossible to predict a "safe" interval before administration of deep sedation or anesthesia. These children would appear to be exposed to a significant risk of regurgitation and possible pulmonary aspiration, necessitating precautions such as rapid-sequence tracheal intubation with application of cricoid pressure.

We question the wisdom of the described method of sedation in this population of patients.

Kirk Lalwani, MD, FRCA
Terry McGraw, MD, FAAP
Departments of Anesthesiology and Pediatrics
Pediatric Sedation Service
Doembecher Children's Hospital
Oregon Health Sciences University
Portland, OR 97210

REFERENCES

1. Pomeranz ES, Chudnofsky CR, Deegan TJ, Rectal methohexital sedation for computed tomography imaging of stable pediatric emergency department patients. Pediatrics. 2000; 105:1110-1114 [Abstract/Free Full Text]
2. Audenaert SM, Montgomery CL, Thompson DE, Sutherland J A prospective study of rectal methohexital: efficacy and side effects in 648 cases. Anesth Analg. 1995; 81:957-961 [Abstract]
3. American Academy of Pediatrics, Committee on Drugs Guidelines for monitoring and management of pediatric patients during and after sedation for diagnostic, dental and therapeutic procedures. Pediatrics. 1992; 89:1110-1115 [Abstract/Free Full Text]
4. Bricker SRW, McLuckie A, Nightingale DA Gastric aspirates after trauma in children. Anaesthesia. 1989; 44:721-724 [Medline]