Effect of continuous deep sedation on survival in the last days of life of cancer patients: A multicenter prospective cohort study

Background: Continuous deep sedation is ethically controversial with respect to whether it shortens a patient's life. Aim: To examine whether continuous deep sedation shortens patient survival from the day of Palliative Performance Scale decline to 20 (PPS20). Design: A part of a multicenter prospective cohort study (EASED study). Setting/participants: We recruited consecutive adult patients with advanced cancer admitted to 23 participating palliative care units in 2017 in Japan. We compared survival from PPS20 between those who did and did not receive continuous deep sedation. Continuous deep sedation was defined as the continuous administration of sedative medication with the intention to keep a patient continuously unconscious to alleviate otherwise uncontrollable symptoms, but the dose of sedatives was adjusted to achieve adequate symptom relief for each patient. The propensity score-weighting method was used to control for potential confounders, and five sensitivity analyses were performed. Results: A total of 1926 patients were enrolled. Patients discharged alive were excluded, and we analyzed 1625 patients of whom 156 (9.6%) received continuous deep sedation. Median survival from PPS20 of 1625 patients was 81 h (95% CI: 77-88). The RASS scores decreased to <=-4 was 66% at 24 h. Continuous deep sedation was not associated with a significant survival risk (adjusted hazard ratio: 1.06, 95% CI: 0.85-1.33). All sensitivity analyses, including continuous deep sedation defined as the RASS score was <=-4 achieved the essentially the same results. Conclusions: Continuous deep sedation with careful dose adjustment was not associated with shorter survival in the last days of life in patients with advanced cancer.