Introduction: Many elderly patients after admission to the cardiac care unit (CCU) are exposed to factors such as stress, which face them with changes in vital signs that these changes could adversely affect these patients' recovery. This study aimed to determine the effect of white noise on the vital signs of elderly patients in the CCU.
Method: This is a quasi-experimental study in which 59 elderly patients in the cardiac intensive care unit of Shaheed Rajai Tehran Heart Center were studied. In this study, samples were selected through convenience sampling and randomly divided into two groups: experimental and control. Vital signs were measured in both groups for 3 consecutive days by charting vital signs. During this period, for the experimental group, white noise with an intensity of 50 to 60 decibels was played for 30 minutes during the day and the elderly patient's vital signs were recorded before and after the intervention, the control group did not have any intervention. Data were analyzed by SPSS, Version 18, by using independent t-test, paired t-test and Chi-square test.
Results: In the present study, 27 elderly patients in the control group and 32 patients in the intervention group were examined. The findings showed that the white noise significantly reduced  heart rate in the intervention group compared with the control group (P=0.02), but comparing other variables such as, systolic blood pressure (P=0.89) , diastolic blood pressure (P=0.73) and respiratory rate (P=0.07) did not show significant differences between the two groups.
Conclusion: According to the results of this study use of white noise can reduce heart rate of elderly patients admitted to the CCU.