Introduction Palliative sedation is sometimes used to manage refractory symptoms in adult palliative care patients in the UK. However, there is limited knowledge regarding which observational tools are most appropriate for monitoring the effects of sedative drugs. This review is a part of the I-CAN-CARE, a Marie Curie funded research programme.

Objective To identify and critique primary studies describing the use of observational measures to assess the depth of sedation at the end of life.

Methods We searched six databases (CENTRAL, Cinahl, Embase, Medline, PsychINFO, Scopus, and Web of Science) until November 2016, using search terms combining subject headings and free-text terms. Primary studies reporting on the use of observational measures to assess the effect of palliative sedation were eligible for inclusion. Two investigators independently reviewed the titles, abstracts and full-text articles retrieved, and performed the data extraction. From the included papers, a list of observational tools, their characteristics and the degree to which they have been validated, using the COSMIN checklist (Mokkink et al., 2010), will be generated.

Results to-date The searches yielded 10 208 articles after removing duplicates. The majority of studies meeting the inclusion criteria and discussing the monitoring of sedation reported using observational measures for assessing not only depth of sedation but also symptom severity. Of the identified scales assessing management of intractable symptoms, only one had been validated for palliative care settings. Five measures assessing level of consciousness had undergone partial validation for use in palliative care. Six of the observational measures identified had been evaluated for their psychometric properties in single study populations.

Conclusions Few measures for monitoring sedation have been evaluated for their psychometric properties in palliative care. Next steps will be a detailed evaluation of the overall quality of the studies identified, and of the validity and reliability of the scales used. Definitive results will become available in February 2017.