Helping the clinician get it right – Diluent selection in subcutaneous infusion

What should nurses use to dilute medications in syringe drivers: water for injection or sodium chloride? This query began a journey for palliative care clinicians; a journey which called into question what constitutes ‘evidence’ in an evidence-based environment, and who within professional and industry bodies takes the responsibility for researching and establishing guidelines on clinical practice associated with specific prescribed medications.

This journey, the queries, the challenges, and the answers, as well as the questions that remain to be answered, provide the foundation for this paper.

In 2004, members of the Palliative Care Clinical Leadership Group (CLG) at Royal District Nursing Service (RDNS) [Victoria] identified the lack of guidelines pertaining to diluent selection for subcutaneous infusion as a clinical issue. CLGs at RDNS have a mandate to pursue evidence-based practice within their clinical specialty. In this case, the Palliative Care CLG followed a process of investigation of current practices and review of the evidence in order to identify and then recommend best practice in diluent use to be implemented across the service.

Unlike many other reviews of evidence, this one found a lack of concise direction for the selection of an appropriate diluent in the preparation of medications. Indeed, the use of certain medications in a subcutaneous manner in palliative care was called into question and further investigation showed that there were a variety of practices related to the use of diluents among Australian palliative care services.

This investigation provides a story of the clinical experiences and challenges encountered by clinicians seeking answers to simple questions. Their journey exemplifies a path taken by many other clinical groups within this evidence-based environment, but brings us to a startling conclusion; that there is, in this case, limited and contradictory evidence and varied practice. These findings call for discussion, clarity, and ownership of decisions on diluent selection by industry and professionals, which will guide the way to consistent and effective practice in the future, for the benefit of our palliative care clients.