Patients´ Experiences of Calorimetry Measurements

Severe burn injury affects the entire body, not only the skin. Profound alterations occur in metabolism, endocrine function, and immune responses, resulting in a hypermetabolic state. This condition is characterized by an increased energy expenditure that may persist for months or even years following injury. Adequate nutritional support is essential to promote wound healing, reduce the risk of infection, and preserve lean body mass. Both underfeeding and overfeeding may adversely affect recovery and clinical outcomes.

To enable safe and individualized nutritional management, measurement of resting energy expenditure (REE) using indirect calorimetry is recommended. During the assessment, the awake patient wears a transparent plastic canopy placed over the head. Oxygen consumption and carbon dioxide production are measured over a period of 10 to 30 minutes to estimate energy requirements. Accurate measurements require the patient to remain still, relaxed, and awake, while refraining from speaking, as physical activity, psychological stress, and other disturbances may influence the results.

Although indirect calorimetry is routinely used in burn care, relatively little is known about how patients experience the measurement procedure itself. Factors such as the hospital environment, pain, anxiety, restricted mobility, and the measurement may influence the patient's experience; however, these aspects have received limited scientific attention. Understanding the patient perspective is important, as discomfort or stress may negatively affect both the patient experience and the quality of the measurement.

The aim of this study is therefore to explore how individuals receiving care for burn injuries experience the assessment of resting energy expenditure by indirect calorimetry.

Data will be collected through semi-structured interviews. Eligible participants will be approached during their burn care admission and provided with both oral and written study information. Written informed consent will be obtained prior to participation. Consent forms and interview data will be stored securely and will be accessible only to the research team.

Interviews will be conducted within two weeks of the indirect calorimetry assessment, either in person at the burn unit or remotely via telephone or video call following hospital discharge. All interviews will be audio-recorded and transcribed verbatim. The interview guide focuses on participants' experiences before, during, and after the indirect calorimetry measurement.

Data will be analyzed using inductive qualitative content analysis. Interview transcripts will be read repeatedly to achieve immersion in the data and identify meaning units, which will be condensed, coded, and grouped into subcategories, categories, and overarching themes. Two researchers will independently code the interviews and discuss interpretations until consensus is reached. The analysis will involve an iterative process of moving between the original text, codes, categories, and emerging themes to develop a comprehensive understanding of participants' experiences. Findings will be reported with illustrative quotations to enhance transparency and trustworthiness.

Through qualitative content analysis of interview data, the study seeks to provide an in-depth understanding of patients' experiences, perceptions, and needs associated with indirect calorimetry. Increased knowledge in this area may contribute to improvements in clinical procedures, patient communication, and preparation before and during the assessment. Ultimately, the goal is to make the measurement process as safe, comfortable, and patient-centered as possible, thereby enhancing both the patient experience and the quality of the measurements used to guide individualised nutritional therapy.