Healthcare workers may fail to respond to medical alarms because they have trouble hearing them — the result of a phenomenon called simultaneous masking, according to a study published in Human Factors.
Simultaneous masking occurs when the human ear is subject to several similar, but different, noises at once.
"We know that our sensory system works as a filter and while that filter, generally, helps us, it can also prevent us from hearing one or more concurrent sounds in certain circumstances," said Andrew Boyd, MD, senior author of the study and an associate professor in the department of biomedical and health information sciences at University of Illinois at Chicago.
For the study, the research team played standard medical alarm sounds for 28 nursing students. Participants were played an initial sound, then played additional sounds, and then asked if the initial sound was present. The students were played the sounds in conditions when simultaneous masking was present and in non-masking conditions.
The study found that students had higher rates of missing the initial sound in masking conditions as compared to non-masking conditions.
"The results show that masking of an alarm's primary harmonic is sufficient to make an alarm sound indistinguishable," study authors concluded.
More articles on clinical leadership & infection control:
Are patient-reported outcome measures woth the effort? 47% of clinical leaders are unsure
Government cuts research program for emerging diseases
Flu activity low, but increasing: 5 CDC updates