Palliative paramedicine: An interrupted time series analysis of pre-hospital guideline efficacy.

Background: Paramedics are increasingly involved in palliative care and often support community-based palliative care service delivery to facilitate integrated practice. However, the impact of specific palliative care guidelines on clinical practice remains unknown.

Aim: To determine the impact of an ambulance service palliative care guideline on rates of supportive medication administration and non-transport.

Design: A retrospective cohort study of electronic patient care records from January 2014 to June 2023. Baseline characteristics were compared pre- and post-guideline introduction. Interrupted time series analysis was performed to examine guideline efficacy.

Setting/participants: Patients of all ages receiving palliative care who were attended by paramedics in Victoria, Australia.

Results: A total of 31,579 patients were included. The median age was 75 years (IQR = 64-84 years), and 56.4% were men. Overall, 25.8% of patients were not transported to hospital. Following guideline introduction, there were no significant trend changes in administration of supportive medications. However, the non-transport rate increased significantly per month (0.2%, p = 0.007), amounting to a 9.9% (p = 0.020) total increase by the end of the study period compared to a scenario in which the guideline had not been introduced. Subgroup analysis of patients diagnosed with 'pain' or attended after-hours also showed significant increases in non-transport (monthly increase: pain 0.3%, p = 0.003; after-hours 0.3%, p < 0.001; total increase: pain 29.7%, p < 0.001, after-hours 22.6%, p = 0.001).

Conclusions: Introduction of a palliative care guideline was associated with a decrease in ambulance transport to emergency departments, allowing more patients continuity of care in the community.