Correlation Between Observational Scales of Sedation and Comfort and Bispectral Index Scores

Abstract

Compared with BIS, both RASS and PCS appear to be relatively blunt instruments at the lower end of their respective scales. Due caution should be taken interpreting and making clinical decisions based solely on the RASS and PCS and, by extension, other observational measures of patient comfort and sedation.

Identification and evaluation of observational measures for the assessment and/or monitoring of level of consciousness in adult palliative care patients: A systematic review for I-CAN-CARE

“…Across all categories, the tool most frequently employed was the original Richmond Agitation-Sedation Scale (RASS) or its modified versions (n = 17). 10,21,35,51,[53][54][55]64,70,72,73,77,84,86,87,91,93 To assess level of consciousness Three of the ad hoc measures were modified versions of the existing tools: the Glasgow Coma Scale (GCS), 32,33 RASS 19,35 and Riker Sedation-Agitation Scale. 23,39 All other ad hoc measures comprised unique tools.…”

Breakthrough Medication in Unresponsive Palliative Care Patients: Indications, Practice, and Efficacy

“…This proposition may strike concern in the hearts of those working in palliative care, but contrary to expectations, BIS monitoring at the end of life is acceptable to relatives of the dying patient, is not disruptive, and does not appear to compromise the sanctity of the dying space. 15,30 In the meantime, there is sufficient circumstantial evidence to suggest opioid þ benzodiazepine is the breakthrough of choice in unresponsive patients, especially for respiratory distress. In relation to palliative sedation, the reduced wakefulness associated with the use of benzodiazepines or other forms of sedation in combination with pain relief is justified and defensible on the grounds of ensuring the adequate relief of patient suffering.…”

“…Technical features of the BIS monitor have been described elsewhere. 15 The RASS and PCS were the instruments of choice because of their validity, 24,25 clarity, minimalism, 16 and good inter-rater reliability in prestudy testing.…”

“…Bispectral Index (BIS) monitoring offers some promise, but the application of this technology within the palliative care setting is in its infancy, and more research is required before its contribution to palliative care is clear. 15,19 To complicate matters further, there is lingering uncertainty about what the BIS monitor measures and the significance of the measurements. 18,20,21 Currently, the experience, expertise, and objectivity of the palliative care practitioner determine the accuracy of their assessment and influence decisions concerning intervention.…”

Palliative sedation: A safety net for the relief of refractory and intolerable symptoms at the end of life

“…24 Another scale is the bispectral index score. 25 Monitoring initially involves 20-minute checks until adequate sedation that controls distressing symptoms has been achieved, after which checks are performed three times per day. 12 If deep sedation is required, then a score of -3 or -4 on the RASS is acceptable.…”