Assessing the value of ANI in non-communicative palliative care patients

The ANI (Analgesia/Nociception Index) is a non-invasive, pain-free technique that assesses the patient's parasympathetic activity through heart rate variability. It has proved reliable for pain assessment during sedation in the context of general anesthesia or for critically ill patients in intensive care units. It has also been shown that ANI values decrease significantly when awake people are exposed to stressful emotional stimuli. Parasympathetic activity thus seems to be a good reflection of the patient's state of comfort, involving not only painful sensations but also stress or anxiety more broadly. Thus, ANI could be a relevant tool for assessing the comfort of non-communicative patients at the end of life. However, there is still some uncertainty as to whether ANI data can be interpreted in palliative care patients in the same way as in ICU patients or those undergoing general anesthesia. Studies to date have shown the feasibility of using this device in the palliative care hospitalization setting and acceptability among caregivers and patients' relatives, but have not demonstrated any validity of their results in end-of-life patients, due to the very limitations of research in this population.

The aim of our prospective, observational, single-center study is to evaluate the value of the ANI in assessing the comfort of non-communicative patients hospitalized in palliative care during painful care such as toileting by comparing, in a blinded fashion, the ANI measurement with caregivers' hetero-assessment of comfort.

Primary objective: To show that there is a significant variation in ANI between the pre-care session period and the care period.

Secondary objective 2: To assess the correlation between variations in ANI and variations in the CPOT hetero-evaluation scale between each period.

Secondary objective 4: Study the discriminative power of ANI to separate the uncomfortable and comfortable population defined by a threshold of ≤2 on the CPOT scale.