Relieve the Patient's Thirst, Refresh the Mouth First (ICU-MIC) (ICU-MIC)

Thirst is considered as one of the most distressing symptoms experienced by patients hospitalized in the Intensive Care Unit (ICU). Whereas pain is a permanent concern for all caregivers, thirst is often ignored and its complications are poorly known. Mechanisms involved in thirst regulation are numerous and complex. To date, care of thirst is still non optimal. Critically ill patients are usually rehydrated intravenously or using a naso-gastric tube, thus shunting the mouth as a therapeutic target to relieve the patient's thirst. Water, cold and mint applied in mouth were studied separately and were shown to decrease thirst significantly on animal models and healthy humans. Therefore, the hypothesis of this study is that application of small mint ice cubes in mouth of very dehydrated ICU patients should allow decreasing quickly and significantly thirst for these patients, before the correction of their biological parameters, like natremia and osmolarity.

Adult patient displaying an hypernatremia upper than 150mmol/L or an hypernatremia upper than 145mmol/L associated with a water deficiency upper than 3L

Physician applies 3 mint ice cubes in mouth of highly dehydrated patient. Patient undergoes an additional blood test at 5 min from mint ice cubes application. Physician performs patient's questioning before mint ice cubes application and at 5 min, 1h, 2h, 4h, 12h and 24h from mint ice cubes application.

Patient's questioning before mint ice cubes application and at 5 min, 1h, 2h, 4h, 12h and 24h from mint ice cubes application

The primary endpoint is a change of thirst intensity of at least 1.5 points on the thirst intensity scale at 5 minutes from mint ice cubes application. Thirst intensity scale is a numeric scale ranging from 0 to 10 points. 0 corresponds to no thirst (the best outcome). 10 corresponds to a thirst of the strongest possible intensity (the worst outcome).

This secondary endpoint is a change of thirst-associated discomfort on the discomfort scale at 5 minutes from mint ice cubes application. The discomfort scale is a numeric scale ranging from on a 0 to 5 points. 0 corresponds to "very comfortable" (the best outcome). 5 corresponds to "very uncomfortable" (the worst outcome).

This secondary endpoint is the delay (in minutes) between mint ice cubes application and the observed effect on thirst intensity.

This secondary endpoint measures how much time (in minutes) mint ice cubes application keeps working on thirst intensity.

Inclusion Criteria: Hypernatremia upper than 150mmol/L or hypernatremia upper than 145mmol/L associated with water deficiency upper than 3L Estimated hospitalization duration in ICU upper than 24h Exclusion Criteria: Contraindication for ice cubes application in mouth Known mint allergy Incapability to understand study outcome and to answer basic questions Pregnancy Dying person