Identifying determinants of noise in a medical intensive care unit

Abstract

Continuous and intermittent exposure to noise elevates stress, increases blood pressure, and disrupts sleep among patients in hospital intensive care units. The purpose of this study was to determine the effectiveness of a behavior-based intervention to reduce noise and to identify determinants of noise in a medical intensive care unit. Staff were trained for six weeks to reduce noise during their activities in an effort to keep noise levels below 55 dBA during the day and below 50 dBA at night. One-min noise levels were logged continuously in patient rooms eight weeks before and after the intervention. Noise levels were compared by room position, occupancy status, and time of day. Noise levels from flagged days (>60 dBA for >10 hrs) were correlated with activity logs. The intervention was ineffective with noise frequently exceeding project goals during the day and night. Noise levels were higher in rooms with the oldest heating, ventilation, and air-conditioning system, even when patient rooms were unoccupied. Of the flagged days, the odds of noise over 60 dBA occurring was 5.3 higher when high-flow respiratory support devices were in use compared to times with low-flow devices in use (OR= 5.3, 95% CI = 5.0 - 5.5). General sources, like the heating, ventilation, and air-conditioning system, contribute to high baseline noise and high-volume (>10 L/min) respiratory-support devices generate additional high noise (>60 dBA) in Intensive Care Unit patient rooms. This work suggests that engineering controls (e.g., ventilation changes or equipment shielding) may be more effective in reducing noise in hospital intensive care units than behavior modification alone.

The Correlation Between Humidity, Temperature, and Noise With Sleep Quality at Intensive Care Unit (ICU)

“…Based on the three variables tested in the logistic analysis, only the noise variable that significantly affected (p = 0.020 (<0.05) the patients' sleep quality. The results of this study support (He et al, 2018)and (Crawford, Barnes, Peters, Falk, & Gehlbach, 2018).The baseline data showed the noise level was between 54 dBA and 88 dBA. These data were collected at night (23.00-02.00).…”

“…However, AC sound does not have a significant positive effect on sleep duration, latency, and efficiency (Alkahtani et al, 2019). WHO (Crawford et al, 2018) recommends that the maximum level does not exceed 40 dBA at night. The sound threshold that causes sleep disturbance is 63 dBA during the day and 59 dBA at night.…”

Innovative ICU Solutions to Prevent and Reduce Delirium and Post–Intensive Care Unit Syndrome

“…47 Attempts to implement behavioral changes to reduce noise levels are certainly necessary, but alone, they have thus far been ineffective. 48 Behavioral-based interventions may only be effective when supplemented by innovative tools, and there is a growing number of technological and architectural solutions that can aid the implementation of acoustics in the hospital setting as a prophylactic or therapeutic measure.…”

The impact of environmental risk factors on delirium and benefits of noise and light modifications: a scoping review

“…Our full-text review and data extraction appraised articles studying single-component noise control strategies, such as behavioral programs [65][66][67][68][69] , earplugs or noise cancelling headphones [71][72][73][74] , and headphones equipped with an alarm filtering system 70 ; however these were not included since they reviewed the impact of interventions on the level of noise or quality of sleep, but delirium was not reported as an outcome (Table 9).…”

“…Staff and family conversations and care-activities are significant sources of ICU noise pollution 16,65,66 . Although behavioral modification might be ineffective as a single-component intervention 67 , low-cost adjustments such as limited bedside conversation, lowered voices, clustered care-activities, minimized TV and overhead use and volume, use of vibrating pagers, and visual noise-warning devices may be necessary to achieve better results in sound reduction 7,14,65,66,68,69 , sleep improvement 66 , and decreased delirium 14 . To be successful, continuous awareness, education of staff on the impact of excessive noise exposure, and routine monitoring of implemented strategies is crucial 7 .…”