Objective: Recent development of noise cancellation devices may offer relief from noise in the intensive care unit environment. This study was conducted to evaluate the effect of noise cancellation devices on subjective hearing assessment by caregivers in the intensive care units.
Design: Randomized, double-blind.
Setting: Adult medical intensive care unit and pediatric intensive care unit of a teaching hospital.
Subjects: Caregivers of patients, including nurses, parents, respiratory therapists, and nursing assistants from a medical intensive care unit and pediatric intensive care, were enrolled in the study.
Intervention: Each participant was asked to wear the headphones, functional or nonfunctional noise cancellation devices, for a minimum of 30 mins.
Measurements: Subjective ambient noise level was assessed on a 10-point visual analog scale (VAS) before and during headphone use by each participant. Headphone comfort and the preference of the caregiver to wear the headphone were also evaluated on a 10-point VAS. Simultaneously, objective measurement of noise was done with a sound level meter using the decibel-A scale and at each of nine octave bands at each bedspace.
Results: The functional headphones significantly reduced the subjective assessment of noise by 2 (out of 10) VAS points (p < 0.05) in environments of equal objective noise profiles, based on decibel-A and octave band assessments.
Conclusion: Noise cancellation devices improve subjective assessment of noise in caretakers. The benefit of these devices on hearing loss needs further evaluation in caregivers and critically ill patients.