Physiologic effects of environmental noise and talking in coronary care patients

Abstract

The purpose of the study was to describe changes in heart rate and blood pressure in patients with acute myocardial disease when exposed to noise and talking in the environment. A convenience sample of ten adult patients admitted to an 18-bed university hospital CCU were selected as subjects. Private rooms separated patients from an open nurses' station. Sound-pressure level and content of sounds were measured with a Bruel & Kjaer type 2230 sound level meter; the microphone was placed above the head of the bed. Heart rate and ECG from the bedside monitor were recorded simultaneously with dBA and sound on a TEAC R-61 physiologic tape recorder and later printed onto a 2600S Gould chart recorder. Blood pressure was measured every 5 min with a Dinamap. Data collection occurred during four 45-min periods on two consecutive days. Mean sound-pressure level of noise sources were: toilet flush-76 dBA, alarms-66 dBA, talking inside the room-65 dBA, and ambient-49 dBA. Repeated measures ANOVAs compared noise sources, content of conversation, and roles of people with changes in decibel, heart rate, and blood pressure. Short bursts of noise showed the greatest mean change in maximum dBA, followed by talking of nurses or doctors inside the room. Heart rate changes were greater when family talked. Mean arterial pressure was higher during talking and background noise. [Work supported by a University Seed Grant.]