A single-center qualitative study evaluating the safety and efficacy of a pharmacist-driven protocol for high-dose methotrexate management

Abstract

Introduction Delayed methotrexate clearance in several patients admitted to the oncology unit at a regional medical center necessitated the development of a pharmacist-driven protocol for supportive therapy with high-dose methotrexate. This performance improvement project evaluated the impact of the protocol on inpatient length of stay, patient safety, and clinical outcomes. Methods Retrospective data were collected over 14 months pre-implementation and prospective data were collected over 19 months post-implementation. Primary outcomes included mean length of stay and incidence of kidney injury. Secondary outcomes included myelosuppression, treatment delays, mucositis, protocol adherence, and pharmacist interventions. Chi-squared and unpaired two sample t-test were used for data analysis. Intervention A literature review of consensus recommendations for supportive care post high-dose methotrexate administration was conducted to develop the protocol. Education on implementation was provided to involved disciplines. Results One-hundred ten high-dose methotrexate admissions for 23 patients were analyzed: 24 pre-protocol and 86 post-protocol. Mean length of stay was 5.17 nights pre-protocol and 3.91 nights post-protocol ( p = 0.026). Incidence of kidney injury significantly decreased (16.7% pre-protocol versus 3.5% post-protocol; p = 0.0394). Lower incidences of all-grade anemia (83.3% versus 58.1%), neutropenia (62.5% versus 29.1%), and thrombocytopenia (58.3% versus 33.7%) as well as treatment delays (29.2% versus 11.6%; p = 0.036) were reported post protocol. No statistically significant difference in mucositis was detected. Pharmacist adherence to protocol was ≥80% resulting in 348 interventions with 99.4% provider acceptance. Conclusion The implementation of a pharmacist-driven high-dose methotrexate management protocol resulted in a statistically significant decrease in inpatient length of stay and kidney injury. Further studies are needed to assess the impact on additional outcomes.