Effect of Dexmedetomidine for Palliative Sedation for Refractory Dyspnoea in Patients with Terminal-Stage Cancer.

Background: Dyspnoea affects a considerable percentage of patients with terminal-stage cancer, and clinical guidelines recommend palliative sedation for patients with refractory dyspnoea. Midazolam is currently the most commonly used sedative; however, it can cause serious adverse reactions, such as respiratory/circulatory depression. Hence, there is a need for an alternative sedative. Dexmedetomidine (DEX) is a promising alternative as its "awake sedation" effect; however, little is known regarding its use in patients with end-stage dyspnoea. Therefore, the aim of this study was to determine the safety and usefulness of DEX for palliative sedation of patients with refractory dyspnoea.

Methods: This retrospective study included patients with terminal-stage cancer who received DEX for palliative sedation owing to refractory dyspnoea in the hospice ward from January 2018 to October 2022. We analysed their general data, dyspnoea conditions, sedation details, sedative treatment effect, dyspnoea relief, and changes in vital signs before and after sedation, via paired -tests.

Results: We included 17 patients with terminal-stage cancer who received DEX palliative sedation at a dose of 0.2-0.9 µg/kg·h for refractory dyspnoea, among whom 6 (35%) received a loading dose of 1 µg/kg in 10 min. After 1 h of sedation and at the maximum sedation dose, the Respiratory Distress Observation Scale and Richmond Agitation-Sedation Scale scores decreased significantly compared with those before sedation (all <0.001), as did the respiratory rate (=0.024 and =0.008, respectively). The heart rate and blood oxygen saturation did not significantly change, whereas the systolic and diastolic blood pressure after 1 h of sedation were significantly lower than those before sedation (both =0.015).

Conclusion: DEX is a promising palliative sedative for patients with terminal-stage cancer, as it safely relieved the symptoms of refractory dyspnoea without inducing serious adverse reactions. Therefore, DEX may greatly enhance the quality of life for patients with terminal-stage cancer.