The Effect of Improved Envıronment Accordıng to Watson's Theory of Human Care on Sleep, Anxıety, and Depressıon ın Patıents Undergoıng Open Heart Surgery: A Randomızed Controlled Study

The aim of this randomized controlled trial was to examine the effect of an improved environment on sleep, anxiety, and depression in patients undergoing open heart surgery. This study aims to answer the following main questions:

• According to Watson's Human Care Theory, what is the effect of the improved environment on patients' sleep level and sleep quality?
• According to Watson's Human Care Theory, what is the effect of the improved environment on patients' anxiety and depression levels? Before collecting data for this study, the "G. Power-3.1.9.2" program calculated the sample size at an 80% confidence level. The "Sample Calculation Formula with Known Universe (Population Volume)" (n = Nz2pq / d2(N-1) + z2pq) determined the sample. The literature review determined the "effect size" value to be 0.096. Taking the primary type error of 5% (Z = 1,96), the test power of 80%, and the effect size value of 0,096 units, we calculated the minimum sample size as n = 60. Therefore, the study included 60 volunteer patients, with 30 placed in the experimental group and 30 in the control group.

Data were collected using the Personal Information Form, the Richard-Campbell Sleep Questionnaire (RCSQ), and the Hospital Anxiety and Depression (HAD) Scale.

The patients who underwent open heart surgery and who were in the experimental group were admitted to the ward from the postoperative intensive care unit and the environment was improved for three days based on the improved environment of Watson's HCT, and on the morning of the fourth day in the clinic, the patients were interviewed face to face and the Personal Information Form, RSCQ and HAD Scale were completed. The following improvements were implemented within the scope of environmental improvement:

• Considering the seasonal conditions, the patient room was ensured to have appropriate temperature (18-26 °C) and humidity values (30-60%), and the temperature and humidity were gradually reduced and maintained in the appropriate range by monitoring at 21:00, 22:00, and 23:00 (Days 1, 2, and 3).
• In line with the environmental arrangements, the brightness of the light in the patient room was gradually reduced at 21:00, 22:00, and 23:00 using the Light Meter LM-3000 (Days 1, 2, and 3).