An audit to review compliance to cisplatin hydration guidelines within the royal Marsden NHS hospital
Authors: Dutto S 
Published: November 2024

Abstract

Introduction
Cisplatin is a cytotoxic agent that forms the backbone of many cancer regimens.1 Cisplatin exhibits good anti-tumour activity however it can accumulate in the renal proximal tubules, leading to nephrotoxicity. It is therefore essential that adequate hydration with diuretics and fluids alongside is administered prior, during and after cisplatin infusion to promote renal perfusion.2
The local policy for intravenous hydration for cisplatin-based regimens states that adult patients are to be weighed prior to treatment and weighed again after treatment to ensure they have not developed fluid retention.3
This audit was necessary following the implementation of the new electronic prescribing system, where nurses no longer got prompted to weigh patients in the same way they did before.

Aim
To assess the level of compliance with current locally approved guidelines for cisplatin hydration administration since the launch of the new electronic prescribing system (EPIC).

Methods
Ethics approval was not required for this audit as retrospective use of anonymous data. Compiled records of 262 patients who were prescribed cisplatin-containing regimens from 17th March 2023 until 31st November 2023 were used to identify patients for inclusion in the audit. Data collection was performed retrospectively using a data collection form and a pilot study was carried out on 20 patients. A sample size of 144 patients was obtained using the Raosoft sample size calculator to achieve a 95% confidence interval with a 5% margin of error accepted.3
All data were collected by the auditor. Patients’ hospital numbers were then individually searched on EPIC to identify if weights were recorded pre- and post-administration of cisplatin. Treatment plans and medical notes on EPR were checked to identify if escalation was appropriately followed where patients gained &gt;2 kg and, in this case to see if furosemide 20mg tablet was given. In addition, laboratory test results and structured notes were reviewed to ascertain if an increase in serum creatinine occurred and if patients were admitted to hospital as a consequence. Data was directly input into Microsoft excel for data analysis.

Results
The majority of cisplatin administration episodes (72%) did have the patient’s weight recorded before and after treatment. Of the remaining 28% where the weight was missing or incomplete, 4 episodes resulted in a documented AKI and 3 of these episodes were severe enough to warrant hospital admission.

Discussion and conclusion
The results demonstrate a lack of documentation of patient’s weights across RMH. Only 72% of patients who were administered IV cisplatin at RMH between 17th March 2023 and 31st November 2023 were recorded. This falls below the local guidance, which recommends all patients (100%) should be weighed pre- and post- cisplatin administration. Documentation is critical to ensure a clear audit trail and to enable identification pf patients who may be at higher risk of developing fluid retention. This therefore needs improvement.
A limitation of the audit is the increased potential for human error due to the way data was collected. The requirement to search through all structured notes and observations flowsheet was time consuming and intensive, increasing the likelihood documentation may have been missed.

References
1. Pabla N, “Cisplatin nephrotoxicity: Mechanisms and renoprotective strategies,” 2008, Kidney Int., pp. 994-1007
2. Loehrer P, “Drugs five years later. Cisplatin,” Ann Intern Med., p. 704–713, 1984.
3. “Cisplatin Hydration Policy,” The Royal Marsden NHS Foundation Trust (Internal document), 2023.