Thirst in ICU Patients: A Scoping Review.

Thirst is one of the most frequently experienced symptoms among patients in intensive care units. Previous reviews of thirst in ICU patients and interventions to alleviate thirst had certain limitations. Therefore, we aimed to systematically explore and map the literature on the prevalence, risk factors, specific measurement methods, and intervention strategies for thirst in ICU patients and to identify areas where further research is needed. A scoping review was conducted to limit the search to studies published by August 2, 2024. A literature search was performed using PubMed, CINAHL, CENTRAL, and Igaku Chuo Zasshi databases. Two reviewers independently screened the literature according to the inclusion and exclusion criteria and extracted data from the selected studies. A total of 53 studies met the eligibility criteria. The combined prevalence of thirst, reported in 11 studies, was 66% (95% CI: 56-76). Four studies reported the risk factors for thirst, including sepsis, gastrointestinal disease, analgesics, diuretics, hyperglycemia, and elevated serum sodium levels, through multivariable analysis. The intensity of thirst and degree of distress were measured using the Numerical Rating Scale, the Visual Analog Scale, and the Likert scale in many studies. The interventions primarily consisted of oral and lip moisturization via sprays and swabs with cold water, many of which were bundled or packaged. The frequency of moisturization interventions for thirst varied from every 30 minutes over a three-hour period to three times a day, and it remained unclear which intervention frequency was the most effective. Other interventions included early oral intake, humidification, and use of music and virtual reality. None of the studies included interventions, such as medication adjustments or electrolyte correction, despite these being recognized as potential risk factors. Future studies should validate the measurement methods and develop objective measurement tools. The intervention types and frequencies that are most effective for treating thirst in ICU patients are unclear. Therefore, further research is required to evaluate the type, timing, and frequency of interventions while considering the identified risk factors.