Title: Baillie Marie Curie PhD Fellowship: Objective monitoring of sedation for patients at the end-of-life: A feasibility study
Funder: Marie Curie

Abstract: As patients approach the ends of their lives they can experience a number of symptoms including pain, agitation, anxiety and breathlessness [2]. Sometimes these problems require the use of sedative medication to treat the symptom directly (e.g. anxiety or agitation) and on other occasions, if the symptom proves to be refractory, sedation may be used as a treatment of last resort to ensure that the patient is not distressed at the very end of his or her life [3, 4]. Sedatives are widely used in palliative care [5] although the prevalence varies according to setting (community, hospice or hospital), country and type of sedation administered (light, deep, continuous or intermittent) [6-12]. In published studies, the prevalence of refractory symptoms requiring sedation has a median value of 20%–30% [3]. Guidelines recommend that patients receiving sedation should be monitored [13, 14] but there is no agreement about the best way to achieve this. Maltoni has recommended that palliative sedation should be “proportionate” and doses of sedatives should be “individually tailored” [15]. However, current practice is often based on an informal assessment about whether or not a patient appears to be “settled” or “comfortable” [16], and objective monitoring is rarely used. This may lead to over or under sedation with adverse consequences for patient care and the experience of relatives [13, 14]. A recent Cochrane systematic review [17] concluded that, “studies that specifically measure the efficacy and quality of life in sedated people, compared with non-sedated people, and quantify adverse effects are required”. Bispectral index (BIS) technology was initially developed to monitor anaesthetic depth during surgery [1]. A forehead sensor collects electroencephalogram information which is subject to signal processing. The sensor is a strip approximately 12cm long which is attached to the forehead and left temple using self-adhesive. Output is expressed between 0 to 100, where 100 indicates full consciousness and 0 an absence of brain activity. BIS is recommended by NICE for monitoring general anaesthesia in patients considered at higher risk of adverse outcomes [18]. It has been suggested that monitoring of sedation in the terminal phase may be similarly important [14]. Only limited pilot work has been undertaken in palliative care patients [19, 20], nonetheless this suggests that BIS may have utility in this population. It is not clear, however, whether this approach would be acceptable to patients, families or professionals working with patients who are dying. The potential benefits of objective sedation monitoring using BIS include the avoidance of over- or under-sedation. BIS monitoring may provide additional information (over and above clinical assessment) to guide the dosage of medication used in end-of-life care. BIS monitoring may also provide reassurance to families and carers about the safe and appropriate use of sedating medications at the end of life. There are, however, potential downsides to objective monitoring including; the “over-medicalisation” of terminal care, the potentially intrusive nature of more intensive monitoring and the uncertainty that might be introduced if BIS scores and clinical monitoring provide discordant results. A recent NIHR HTA review [21] of depth of anaesthesia monitors (including BIS) concluded that this technology can affect clinical outcomes (e.g. lower drug doses, quicker recovery times). Previous research in patients receiving general anaesthesia suggests that BIS monitoring can result in reductions in general anaesthetic consumption [22]. There is an emerging body of knowledge that examines the usefulness of BIS for monitoring sedation in different settings [23] including endoscopy [24-26], ICU [27], the Emergency Department [28, 29] or dental surgical [30-32] settings. The PhD student will explore the feasibility [33] of using BIS technology in patients who are dying. The purpose of this research will be to improve the care of patients in the terminal phase by undertaking work preparatory to a full scale randomised controlled trial (RCT) of sedation monitoring and dose titration in patients at the end-of-life (for which external funding will be sought). The precise aims of the PhD thesis will be determined in consultation between the supervisory team and the successful candidate. The PhD student will work on WP1.2 of the I-CAN-CARE programme and will collect data for the feasibility study to evaluate BIS monitoring of sedation levels in patients in the last few days of life. However, as described in above, the student will also wish to develop his or her own research questions that are complementary to the aims of WP1.2. This may involve additional data collection or analyses on data collected in WP1.2 or it may involve collection of additional data from a separate population of patients. We will work with the student to ensure that the chosen project dovetails with the work of the I-CAN-CARE programme and provides added value to both.


Research activity codes: 7.2 END OF LIFE CARE
Health categories: GENERIC HEALTH RELEVANCE