Laryngoscope Illuminance in an Academic Medical Center: Industry Standards and Implications for Quality Direct Laryngoscopy

Abstract

Objectives:

Compare laryngoscope illuminance to established standards and identify maintenance and design features associated with poor light output.

Methods:

An observational study in a tertiary-care medical center (level-one trauma center, specialty cardiac hospital, and general hospital) was performed from January-November 2012. Illuminance (lux) was chosen as the unit of measurement. Laryngoscopes in the main operating room (OR), cardiac OR, outpatient OR, emergency department/trauma bay (ED), and code carts were tested using a standard technique. International Standards Organization (ISO) and medical literature values were used for comparison. Maintenance practices were surveyed.

Results:

Six hundred ninety-one laryngoscopes were tested. Devices varied by light source and design, including light-emitting diode (LED), incandescent bulb (on-blade and in-handle), and xenon. The lowest illuminance was observed by incandescent designs (bulb on-blade, 820±700 lux, n=237; bulb in-handle 1860±1220 lux, n=79), followed by LED (4730±3210 lux, n=354), and xenon source (28800±34500 lux, n=21). Forty units (6%) failed to turn on at all, classified as failing, (11% bulb on-blade, 6% LED). Compared to illuminance benchmarks for laryngoscopy in the medical literature (867 lux) and ISO (500 lux), 59% of incandescent laryngoscopes, 12% of LED laryngoscopes, and 10% of xenon units did not meet quality standards for laryngoscopy (7% devices overall). All units were cleaned by standard protocols, but no departments reported regular equipment maintenance.

Conclusions:

Up to 13% of laryngoscopes in an academic medical center were found to be substandard. Quality-control programs may reduce numbers of deficient laryngoscopes in circulation, improving airway management and patient care.