Evaluation of the Reliability of 5-FU Elastomeric Pump in an Ambulatory Infusion Center

Presenter: Quan Li, PharmD, BCOP, BCPS, Clinical Coordinator, MedStar Washington Hospital Center, Washington, DC

Co-Author: Alice Beers, BSN, OCN, NPD-BC, MedStar Washington Hospital Center, Washington, DC

BACKGROUND: Continuous infusion of fluorouracil (5-FU) is often used in the treatment of gastrointestinal (GI) malignancies through an ambulatory infusion pump.^1,2 However, the infusion rate of elastomeric pumps is affected by environmental and patient factors.^3,4 Monitoring drug delivery by the pump is essential to treatment efficiency and drug safety.⁵ Visual inspection, as recommended in the package insert, is not reliable. A quantitative method to assess the delivery of 5-FU via an elastomeric pump is in great need. Recently, Cusano and colleagues showed the feasibility to monitor 5-FU delivery via Baxter elastomeric pump by comparing pump weights before and after infusion.⁶ However, more than 24% of the pumps had remaining fluid of >10%, suggesting insufficient delivery of the elastomeric pumps.^6,7

OBJECTIVE: To evaluate the reliability of SMARTeZ elastomeric pump to deliver 5-FU, by measuring the percentage of pumps that deliver >90% of expected 5-FU dose at the end of 46 hours of infusion.

METHOD: This retrospective chart-review study included patients who were at least 18 years old, diagnosed with GI cancer and treated with intravenous 5-FU continuous infusion over 46 hours through elastomeric pump between April 1, 2021, and September 30, 2021. Pregnant females or patients younger than 18 years old were excluded. The primary end point was the reliability of the 5-FU elastomeric pump, measured by the percentage of elastomeric pumps delivering >90% of expected 5-FU doses. Secondary end points included the average percentage of 5-FU delivery of each pump, the average weight of empty, and full and returned empty pump.

RESULTS: A total of 24 patients and 117 pumps were included in the analysis. Overall, 95.7% of the patients received >90% of expected 5-FU dose. The average percentage of 5-FU delivery was 94.9% ± 7.3%. The average weight of empty, full, and returned pumps was 92.9 g ± 1.3 g, 335.1 g ± 1.5 g, and 105.4 g ± 17.7 g, respectively.

CONCLUSION: SMARTeZ elastomeric pumps were reliable to deliver 5-FU continuous infusion over 46 hours for patients with cancer.

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