The Case

An 8-year-old boy falls while playing ice hockey. He has an isolated distal radius fracture that needs a closed reduction. The patient had been eating a bag of chips one hour ago, and you wonder if you need to wait before performing procedural sedation.

Background

Procedural sedation is a common practice in the emergency department. The American Society of Anesthesiologists 2011 Practice Guidelines recommend fasting from the intake of clear liquids for at least two hours, fasting from the intake of a light meal for at least six hours, and fasting from the intake of fried or fatty foods or meat for eight or more hours.¹ They do acknowledge that these guidelines may not apply to emergency care.

The ACEP 2013 Clinical Policy on procedural sedation and analgesia in the emergency department recommends not delaying procedural sedation in adults or pediatric emergency department patients based on fasting time (Level B).² This is because “pre-procedural fasting for any duration has not demonstrated a reduction in the risk of emesis or aspiration when administering procedural sedation and analgesia.”

Clinical Question

Does procedural sedation of a pediatric emergency department patient need to be delayed based on nil per os (NPO) status?

Reference

Beach ML, Cohen DM, Gallagher SM, et al. Major adverse events and relationship to nil per os status in pediatric sedation/anesthesia outside the operating room: a report of the pediatric sedation research consortium. Anesthesiology. 2016;124(1):80-88.

• Population: All pediatric patients undergoing procedural sedation at one of the 42 Pediatric Sedation Research Consortium (PSRC) sites. Procedural sedation/anesthesia was defined as “any pharmacologic intervention made to facilitate an invasive procedure or test in a pediatric-age patient outside of the operating room environment.”
• Intervention: NPO to solids for at least eight hours, non-clear fluids for at least six hours, and clear fluids for at least two hours.
• Comparison: Patients who failed to meet the above NPO criteria.
• Outcome: Two primary outcomes:
  • Rate of aspiration. Defined as an event where emesis was noted or food material was found in the oropharyngeal cavity and associated with any of the following: new cough, wheeze, increase in respiratory effort, change in chest radiograph indicative of aspiration, or new need for oxygen therapy after recovery from sedation.
  • Occurrence of a major adverse event. Defined as aspiration, death, cardiac arrest, or uoonplanned admission to a hospital.

Authors’ Conclusions:

“The analysis suggests that aspiration is uncommon. NPO status for liquids and solids is not an independent predictor of major complications or aspiration in this sedation/anesthesia data set.”

Key Results

There were 139,142 procedural sedation/anesthesia encounters identified in the data set. NPO status was known for 107,947 patients, including 25,401 (24 percent) who were not NPO. They observed 75 major complications that included 62 unplanned admissions, 10 aspirations, three cardiac arrests, and no deaths.

• Primary outcome: No statistical association between NPO status and major complications or aspiration was shown.

EBM Commentary

1. Association versus causation: A prospective observational study like this can be used to identify associations between NPO status and aspiration and major adverse events. However, it would take a randomized controlled trial to investigate causation.
2. Precision of the results: Because there were only a few events, the 95 percent confidence intervals around the point estimate were wide.
3. External validity: High-performance sedation teams provided the procedural sedation in this study. You may not have these teams in your community hospital. In addition, the majority of these elective procedural sedations were classified as routine, not emergency, and only a minority of the sedations were provided by an emergency physician.

Bottom Line

Not delaying procedural sedation in pediatric emergency department patients based on their NPO status is reasonable.

Case Resolution

You have an informed discussion with the parents regarding their son’s injury and the risks of sedation. You proceed with the sedation and perform a closed fracture reduction with no complications.

Thank you to Dr. Robert Edmonds, an emergency medicine staff physician at Langley Air Force Base. (Note: The views and opinions of this article are not the official position of the United States Air Force or Langley Air Force Base.)

Remember to be skeptical of anything you learn, even if you heard it on the Skeptics’ Guide to Emergency Medicine.

References

1. Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: application to healthy patients undergoing elective procedures: an updated report by the American Society of Anesthesiologists Committee on Standards and Practice Parameters. Anesthesiology. 2011;114:495-511.
2. Godwin SA, Burton JH, Gerardo CJ, et al. Clinical policy: procedural sedation and analgesia in the emergency department. Ann Emerg Med. 2014;63(2):247-58.e18.