Patients are at risk for deleterious physiologic effects of noise. Exposure to noise in a critical care unit may trigger a sympathetic nervous system response thereby increasing cardiovascular work in the cardiac surgery patient.

This quasi-experimental, repeated measures study explored the relationships among noise sensitivity, noise levels, noise annoyance, and physiologic variables in a sample of 40 cardiac surgery patients. This research also investigated the effects of a music intervention given twice on the first postoperative day on noise annoyance, heart rate (HR), arterial blood pressure (ABP), and electrocardiogram ST-T segments (ST-T) in high (n = 22) and low (n = 18) noise sensitivity subjects.

Repeated measures analysis of variance found that subjects had lower noise annoyance levels during music intervention compared with baseline (p = 0.0001). HR (time 1, p = 0.0009, time 2, p = 0.0022) and systolic blood pressure (SBP) (time 1, p = 0.0397, time 2, p = 0.0152) decreased during the music intervention compared with baseline. Diastolic BP decreased during the music intervention from baseline during time 2, but not time 1 (time 1, p = 0.2336, time 2, p = 0.0111). No change in mean arterial BP or ST-T segment levels occurred.

Subjects with high baseline noise sensitivity scale (NSS) scores preoperatively had higher baseline Noise Annoyance Visual Analogue Scale (NAVAS) scores in the critical care unit the first postoperative day (p = 0.0392). There were no differences in HR, BP or ST-T levels during baseline and intervention between subjects with high or low noise sensitivity or noise annoyance.

Subjects rated the music intervention as highly enjoyable regardless of their baseline noise sensitivity or noise annoyance. The music intervention experience was described as a positive experience by 85% of subjects.

Noise generated by staff and equipment noise were described as the most annoying to the subjects. Environmental noise levels did not correlate with NAVAS scores. Multiple regression analysis did not determine NSS scores, NAVAS scores or noise levels to be predictive of physiologic variables in this sample.

This study supported the conceptual framework; noise annoyance is a highly individual phenomenon, influenced by a transaction of personal and environmental factors. Use of a music intervention with cardiac surgery patients during the first postoperative day decreased noise annoyance, HR and SBP, regardless of subjects' noise sensitivity.