Laryngoscope illuminance in a tertiary children's hospital: implications for quality laryngoscopy

JAMA Otolaryngol Head Neck Surg. 2014 Jul;140(7):603-7. doi: 10.1001/jamaoto.2014.676.


Importance: Laryngoscopes are used by otolaryngologists in a variety of hospital emergency and critical care settings. However, only rarely have quality-related aspects of laryngoscope function and application been studied.

Objectives: To compare the illuminance of laryngoscopes commonly used in a hospital setting to established standards and to assess the potential effects of maintenance practices on laryngoscope illuminance.

Design, setting, and participants: Observational study of laryngoscope light output and cross-sectional survey of individuals charged with laryngoscope maintenance in a tertiary care children's hospital.

Interventions: Illuminance was chosen as the unit of measurement (lux). Laryngoscopes in the operating room, emergency department, and pediatric intensive care unit were tested according to a standard technique. Illuminance standards for laryngoscopes, published by the International Organization for Standardization (ISO) (500 lux) and in the medical literature (867 lux) were used as benchmarks.

Main outcomes and measures: Mean laryngoscope illuminance by type of laryngoscope and light source and percentage of laryngoscopes with illuminance below established standards as well as nonfunctioning units. Maintenance practices were evaluated as a secondary outcome.

Results: A total of 319 laryngoscopes were tested; 283 were incandescent bulb units used by anesthesiologists, emergency physicians, and intensivists and 36 were xenon light units used by otolaryngologists. Mean (SD) illuminance was 1330 (1160) lux in the incandescent group and 16,600 (13,000) lux in the xenon group (P < .001). Substandard illuminance was observed only in the incandescent group, in 29% to 43% of laryngoscopes; 5% of the incandescent group did not turn on at all. Maintenance of laryngoscopes was performed on a reactive rather than a preventive basis.

Conclusions and relevance: At our facility, approximately one-third of incandescent laryngoscopes exhibited substandard light output. On the basis of these findings, our hospital has converted all of its incandescent laryngoscopes to light-emitting diode (LED) devices. Such changes, as well as the institution of a quality-control program including scheduled laryngoscope inspection and battery and bulb replacement for incandescent laryngoscopes, may reduce adverse events associated with poor-quality direct laryngoscopy.

MeSH terms

  • Cross-Sectional Studies
  • Emergency Service, Hospital
  • Hospitals, Pediatric
  • Humans
  • Intensive Care Units, Pediatric
  • Laryngoscopy / instrumentation
  • Laryngoscopy / methods*
  • Laryngoscopy / standards
  • Lighting / standards*
  • Operating Rooms
  • Tertiary Care Centers