Coronary artery disease (CAD) is the leading cause of mortality and morbidity worldwide. Coronary Angiography (CAG) is an invasive method used in the diagnosis and treatment of CAD. Invasive methods such as coronary angiography cause pain. The sympathetic nervous system is stimulated and vital functions can be affected by the increased stress level of the pain experienced. In the angiography laboratory, patients are awake, aware of everything, and can easily hear the sounds of the monitor and the comments and conversations of the healthcare team. This auditory exposure can further trigger the patient's fear and anxiety and increase their pain. Increased anxiety can lead to an increase in the intensity of perceived pain and a decrease in pain tolerance. In addition to anxiety, catastrophizing such as fear of death can also be a means for disability and complications. In the literature, it is recommended to use nonpharmacological methods together with pharmacological treatment to increase pain tolerance and improve patient comfort and satisfaction in patients affected by invasive procedures. Nonpharmacological methods, unlike pharmacological agents, do not cause any harm to patients. It can help to keep physiological parameters such as blood pressure, respiration and pulse rate at normal levels and to increase comfort and satisfaction with the procedure. Sound therapy, which is a non-pharmacological method, turns the person's attention from negative stimuli to positive and hopeful feelings and can reduce stress, anxiety and pain.

Non-pharmacological methods such as white noise therapy and using earplugs that prevent sound permeability can be used to distract the patient's attention from the source of stress and focus on other thoughts. It is suggested that patients exposed to 50 to 55 dB white noise experience pain relief and have an effect on heart rate and oxygen saturation (12). As a result of our literature review, no studies were found where white noise was applied during coronary angiography. This situation reveals the originality of our study. With white noise, the patient can be isolated from ambient sounds during the procedure and the stress experienced can be controlled, the increase in pain intensity and decrease in tolerance that may occur due to stress can be controlled, and the patient's comfort and satisfaction level during the procedure can be increased. We think that the patient's compliance during the procedure can be increased.

The noise in the units affects the anxiety levels of the patients. The literature supports that the use of earplugs increases the comfort of the patient. In the study investigating the effect of auditory interventions on pain and comfort, it was determined that the pain level and heart rate were lower and the comfort level was higher in patients using earplugs compared to the control group. More evidence is needed on the effect of earplugs on physiological parameters, pain, comfort and procedure satisfaction of the patients by applying them to different patient groups. As a result of our literature review, no study was found where earplugs were applied during the coronary angiography procedure. This situation reveals another originality of our study.

The nurse involved in every step of coronary angiography aims to ensure that the patient benefits from the procedure to a high extent and to increase the quality of the procedure by integrating innovative methods. Nursing practices that increase the quality of the procedure are included in national and international nursing care guidelines. Therefore, in order to implement quality nursing care, it is necessary to increase the number of randomized controlled experimental studies and to increase the level of evidence. The fact that our study was a pre-test post-test randomized controlled double-blind study will increase the level of evidence in this regard. This situation reveals another originality of our study.

This study will use a randomized pre-test and post-test control group experimental design. It is planned that a total of 150 patients will participate in the study; 50 in the white noise group, 50 in the earplug group, and 50 in the control group. Data of the study will be collected via ''Personal information form, Numeric Pain Scale (NPS), Numeric Satisfaction Scale (NMS), Numeric Comfort Scale (NKS)''. A web-based randomization system will be used to determine the groups in the study. Pulse rate, respiratory rate, systolic blood pressure (SBP), diastolic blood pressure (DBP) and oxygen saturation values (SpO2) will be evaluated before, during, and after the procedure. Pain, satisfaction, and comfort levels will be evaluated at the end of the procedure. Interventions will be performed by the researcher and the patients will be observed throughout the intervention.

Inclusion Criteria:

• Patients who do not have vision, hearing, speech or comprehension problems, are 18 years of age or older, are open to communication and cooperation, do not have a psychiatric disease and agree to participate in the study will be included in the study.

Exclusion Criteria:

• Those with cognitive impairment or any auditory problems that may affect the test results, or those using psychoactive drugs will not be included in the study.