The impact of dyspnea levels on delirium in chronic obstructive pulmonary disease patients undergoing non-invasive mechanical ventilation in the intensive care unit

This study was conducted to examine the effect of dyspnea severity on the development of delirium in patients with Chronic Obstructive Pulmonary Disease (COPD) receiving non-invasive mechanical ventilation (NIMV) in an intensive care unit. It aimed to contribute to a holistic approach to clinical care by evaluating dyspnea and cognitive impairments (particularly delirium) together. The research employed a descriptive and cross-sectional design and was carried out between December 2024 and May 2025 in the intensive care unit of a state hospital in Istanbul. The sample size was calculated using the G*Power program with a medium effect size (0.50), 95% confidence level, and 80% power, yielding a minimum of 128 participants. Ultimately, 132 patients who met the inclusion criteria and volunteered were enrolled. Data were collected using a Patient Identification Form prepared by the researcher, the validated Dyspnea-12 Scale, and the Nursing Delirium Screening Scale (Nu-DESC). These instruments were administered after clinical stabilization, both before NIMV initiation and on the fifth day of treatment. Descriptive statistics, t-tests, ANOVA, and Pearson correlation coefficients were used for data analysis. The mean Dyspnea-12 score decreased significantly from 26.32 ± 8.63 before NIMV to 17.98 ± 10.42 on day five (p < 0.001). Conversely, the Nu-DESC score increased from 2.76 ± 2.43 to 4.09 ± 4.19, also showing a highly significant difference (p < 0.001). A moderate positive correlation was identified between dyspnea and delirium, with correlation coefficients of r = 0.544 at baseline and r = 0.599 on day five (p < 0.001). Advanced age, longer disease duration, and frequent exacerbations increased the risk of delirium, while sex and smoking status were not significant factors. The findings demonstrated that NIMV effectively controlled dyspnea in COPD patients but was insufficient to prevent delirium on its own. Increased dyspnea severity elevated the risk of delirium, indicating that these symptoms may mutually reinforce each other over time. These results emphasize the importance of assessing cognitive function alongside respiratory parameters in the intensive care of COPD patients and highlight the critical role of nurses in early detection and timely interventions to improve patient outcomes.