Because of the complexity of the problem (discomfort is the result of many factors that, for ethical and practical reasons, researchers cannot control) and the explorative nature of this study, it would be conceived as a multi-case study in which the setting and participants are deliberately chosen. The aim is not to achieve representativity, but rather to describe some typical cases which can provide maximum insight.
Participants
In modal hospitals and modal homes for the elderly, forty patients will be selected. In each setting 20 participants will be included consecutively, which should result in 40 detailed case studies. Patients will be deliberately selected to gain maximum insight and reflect variability regarding medical conditions.
Inclusion criteria
Patients may be included if they are considered by their treating physician as:
1.
in their last week of life
2.
in conditions that might, when not treated, cause high levels of distress
3.
palliative sedation will be started
The treating physicians (specialists at the PCU/ICU or general practitioners at homes for the elderly) will be asked to determine whether or not the patients meet these conditions by means of a checklist on these 4 criteria. To optimally reflect daily practice, no further specific instructions will be given on how to evaluate these criteria and treatment will be according to the physician’s judgment and the best practice.
Procedures
For this prospective study methods from social sciences (qualitative data collection based on interviews, observation), quantitative assessments (scales to assess awareness and discomfort) and neurophysiological data will be combined. Hence, a combination of methods that can be considered fairly objective (e.g. EEG and physiological parameters) and rather subjective methods (e.g. observations by family members) will be used to assess discomfort and awareness. Therefore, the following data will be collected:
1. Assessment by caregivers (physicians and nurses) in the routine manner. As explained above, this can be based either on their ‘experience’ or on tools they routinely use in their practice. Every day all treating physicians and nurses will be asked to fill in a brief questionnaire (3 VAS scales) on the patient’s level of awareness (no awareness- completely aware), comfort (no pain – very severe pain) and ability to communicate (no communication possible - full communication possible). After the patient has deceased, all caregivers will be interviewed and asked to comment on their assessments.
2. Family members’ perception of the quality of the dying process, their opinion about the patient’s comfort and awareness and their impression of whether they had any kind of (non-verbal) contact with the patient. Parallel with the above described procedure, family members will also be asked to fill in the same 3 VAS scales. Semi-structured interviews will be conducted before and after the patient has deceased.
3. Assessment by 2 trained investigators using 1 scale that is mentioned in the Flemish palliative sedation guideline and 3 other scales that have been proposed in the literature [
16]:
3.1
CCPOT (Critical Care Pain Observational Tool), a tool specifically developed for use in patients with limited consciousness [
8].
3.2
RASS (Richmond Agitation-Sedation Scale) [
21].
3.3
M-ESAS (Modified Edmonton Symptom Assessment Scale, validated for a Flemish Palliative Care Population) [
22].
3.4
BPS-NI (Behavioral Pain Scale Non-Intubated) [
23].
4. Neurophysiological assessments of distress and level of awareness using fMRI has been successfully used to detect awareness and distress that could not be detected by thorough behavioral assessment [
10,
13,
14,
24,
25]. Issues of availability and extra stress incurred by patients when transferred are making the use of fMRI for practical and ethical reasons not feasible.
EEG has recently been shown to provide a feasible and methodologically sound alternative for bedside detection of awareness and pain [
26‐
28]. Although results from these methods need to be interpreted with caution, they can provide important indicators that are especially valuable for assessments in non-communicative patients. Data will be collected with a Neurosense monitor that can easily be used and set up. It displays two frontal EEG signals, and calculates a number of parameters including the bilateral WAVcns index (Wavelet Anesthetic Value for Central Nervous System), ranging from 100 (awake) to 0 (flat EEG). The lower the index, the lower the likelihood of consciousness. The recommended WAVcns for general anesthesia with low probability of consciousness is between 60 and 40. For technical details on the respective measurements of awareness and distress we refer to Schulz E et al. and Cruse D et al. [
24,
29].
Additionally, heart rate variability (HRV) will be measured using an ANI monitor. HRV is the variation in time intervals between heartbeats and reflects the effect of the vagus nerve on the heart, which is inhibited during pain. It has already been widely studied in relationship to pain, and seems to be a promising biomarker [
30]. However, studies with palliative sedated patients show contradicting results thus far [
31,
32]. A promising non-invasive technique is the continuous monitoring of HRV transformed into an analgesia nociception index (ANI, 0–100), which assesses parasympathetic activity as a possible measure of nociception [
33]. The ANI provides greater stability than raw indices of HRV. A recent study showed that ANI is effective in detecting pain in deeply sedated critically ill patients [
34]. The analgesia nociception index is a non-invasive tool based on the analysis of the respiratory fluctuations of heart rate that mainly reflect the variability in the parasympathetic tone. The NeuroSense and ANI monitor record the EEG and ECG signal continuously, enabling a quantitative assessment of these parameters. The data can be used to assess the level of sedation but also to register negative and positive emotion-related activities such as the voice of loved ones and distress.
5. Observation of the patient to detect e.g. restlessness, movements etc. To assure a more precise and reliable observation, video and audio registrations will be made of the patient.
6. Background information based on the patient’s medical file, observation and interviews.
6.1
Characteristics of the patient (age, gender, profession…).
6.2
Medical information: history, medical condition, feeding, medication, etc.).
6.3
Pharmacological information (especially medication aimed to improve comfort e.g. sedatives, painkillers etc.)
6.4
Environmental information (e.g. the presence of next of kin, noises etc.)
Data will be collected every day, starting from the day when palliative sedation is initiated until the patient dies. Neurophysiological data will be collected continuously. Video and audio registrations will preferably take place non-stop (in consultation with the family) but may be interrupted during family visits to respect privacy.
Data-analysis
Analysis of qualitative data (interviews and video) will be done in accordance with the interpretative paradigm, aiming to understand meanings and actions and how people construct them, and follow the principles of Grounded Theory [
36]. Coding of the neurological data will be performed by an experienced neurologist.
Video registrations will be coded in events and analysed using nVivo, a tool for qualitative analysis that enables researchers to code and analyze events and also allows importing and correlating video and neurophysiological data. A coding scheme will be developed to code behavioral signs of the patient, treatments (painful acts, medical acts, etc.) and environmental circumstances and changes (visits, noises…).
The involved researchers will intensively cooperate in the interpretation of the data. All data will be used for an overall assessment (using the transdisciplinary mixed methods case study approach) [
37]. The analysis will focus on:
The findings and interpretations will then be discussed in a multidisciplinary team consisting of members of the Mental Health and Wellbeing Research Group, the department of Anesthesiology and Perioperative Medicine, the department of Experimental Psychology (all from the Vrije Universiteit Brussel) and the Coma Science Group (University of Liège).
Ethical aspects
Video/audio registration will only be made after explicit consent of the patient (if possible) and his next-of-kin.
The study protocol is approved by the biomedical ethics committee of the VUB/UZ Brussel (BUN 14320136504) and additional approval will be asked from participating hospitals. Written informed consent will be asked from the patient or his/her substitute decision maker.
We are aware that the data collection is challenging and delicate, especially because we will deal with dying patients and their family. Therefore, special attention will be given to clear communication about the aims of our study. We will explain participants that the study is not invasive and will not hinder the (sedated) patient and that the aim is to minimize the risk for suffering.