Factors Influencing Thirst in Patients in the Intensive Care Unit

The systematic review discussed in this Evidence Review Summary analyzed factors influencing thirst in intensive care unit (ICU) patients.1Thirst is a critical physiological mechanism essential for maintaining fluid homeostasis and overall human well-being.2 Thirst is particularly relevant in the ICU due to the high prevalence of conditions such as hypovolemia, heart failure, and renal impairment, which elevate fluid requirements. Despite intravenous hydration, many patients in the ICU experience considerable thirst due to factors such as xerostomia (dry mouth), mouth breathing, the use of dry medical gases, endotracheal intubation, impaired communication, and side effects from medications, including diuretics, anticholinergics, and antihypertensives.3Although thirst is among the most frequently reported and intensely perceived symptoms in the ICU (up to 70%), there is a wide variation in how it is managed.3 Nurses are often the clinicians identifying and managing thirst, highlighting the need for targeted education and protocols. Mouth care, a potentially effective intervention for alleviating thirst, is inconsistently implemented and primarily emphasized in the context of ventilator-associated event prevention.3 Given the impact of unrelieved thirst on patient comfort and well-being, the development and integration of standardized assessment and management strategies in ICU protocols is necessary, and having insight into the associated factors is the key first step.The current evidence focusing on thirst in the ICU includes both quantitative and qualitative research. As such, the systematic review used a mixed-methods approach.1 A mixed-methods systematic review integrates findings on intervention effectiveness from quantitative studies with insights into patient experiences from qualitative research, providing a more comprehensive understanding of how an intervention works and a complete evaluation of the research to guide clinical decision-making.4This summary is based on a systematic review conducted by Xie et al1 of 13 studies, including 10 crosssectional studies, 1 cohort study, and 2 qualitative studies. The combined sample size included 3107 adult patients (≥18 years old). Xie et al1 independently assessed the risk of bias for each study, including selection, performance, detection, attrition, reporting, and publication biases. The quality of the included studies was evaluated using the Mixed Methods Appraisal Tool and JBI critical appraisal tools. Any disagreements were resolved by reviewing the data together and through an additional reviewer.1 All of the studies were found to be of medium to high quality. The systematic review process followed the JBI approach for mixed-methods systematic reviews.4The results were presented in 2 qualitative synthesized findings (overall themes) and 2 quantitative elements: the incidence of thirst and influencing factors.1In their systematic review, Xie et al1 provide insight into the factors associated with thirst in adult patients in the ICU. The themes from both the quantitative and qualitative research included personal characteristics (eg, marital status, smoking), disease factors (eg, heart failure), treatment factors (eg, diet, medication, ventilator), psychological factors (eg, anxiety), and nurse factors (eg, insufficient assessment and treatment). The high incidence rate of 87%, along with prolonged duration and distress, indicates the importance of the issue. In addition, the numerous factors that influence thirst suggest that a thorough assessment be conducted regularly and that management plans be multifactorial.These findings align with other published data, which include recommendations that thirst should be evaluated daily and that associated treatment plans should be made.3 These recommendations highlight the need for identification and early treatment of thirst and show that they should be part of ICU standard practice. Although treatment plans were not the focus of the systematic review, other evidence should be evaluated to determine how best to manage thirst in patients in the ICU. Among the many interventions are regular oral care, use of ice, and bundled approaches conducted several times throughout the day.5The evidence from the systematic review can affect clinical care team decisions when they are creating treatment plans for patients in the ICU. As nurses caring for critically ill patients, advocating for the best evidence-based treatment remains an important part of our role. We must always consider the best available evidence and understand the feasibility, appropriateness, meaningfulness, and effectiveness of any intervention to determine whether it is most appropriate to implement in our individual context.