UK
Clinical Pharmacy
Association
UK
Clinical Pharmacy
Association
A recent audit at Chelsea and Westminster Hospital NHS Foundation Trust assessed how effectively UFH therapy is prescribed, monitored, and managed in adult inpatients.
Venous thromboembolism is a potentially life-threatening condition, and anticoagulation remains central to its treatment. Although direct oral anticoagulants (DOACs) have become increasingly common, unfractionated heparin (UFH) continues to play a critical role in hospital practice. Its rapid onset of action, short half-life, reversibility, and safety in patients with renal impairment make it an essential therapy in specific settings. However, UFH carries significant risks due to its narrow therapeutic window. Safe and effective management therefore relies on accurate dosing, close monitoring, and timely adjustments, making it essential to evaluate hospital compliance with clinical standards.
The audit reviewed UFH therapy across medical, surgical, and critical care wards. It focused on whether VTE risk assessments were completed within 14 and 24 hours, in line with the national target of at least 95%. It also examined whether UFH prescribing was clinically appropriate, measured against a local target of 95%, and assessed the management of therapeutic UFH, including baseline safety checks, dosing accuracy, and activated partial thromboplastin time ratio (APTTR) monitoring, with a local standard of at least 90%. The evaluation was designed to provide insight into how hospitals can improve anticoagulation safety and ensure UFH is used appropriately in adult inpatients.
Between June and November 2024, data were collected retrospectively from 63 adult inpatients receiving therapeutic UFH, either by intravenous infusion or subcutaneous injection. Information was obtained from electronic patient records, VTE risk assessment forms, pathology and radiology results including renal function, and prescribing and monitoring documentation. The findings were then compared against agreed audit standards to determine compliance with both national and local guidance.
The audit identified strengths in prescribing practices and baseline safety but revealed significant gaps in monitoring. VTE risk assessments were completed for 87% of patients within 14 hours and for 90% within 24 hours, both figures falling short of the 95% national standard. Clinical indications for UFH were appropriate in 97% of cases, while baseline blood tests were completed prior to initiation in 98% of patients. Correct dosing was generally strong, with 88% of patients receiving the appropriate loading dose and 91% prescribed the correct maintenance dose. However, APTTR monitoring was inconsistent: only 68% of patients had their levels checked within four to six hours of initiation, and just 60% were monitored after dose adjustments. These findings highlight a major safety concern, given the risks associated with inadequate monitoring of UFH therapy.
The findings underline that while UFH prescribing practices were generally strong, monitoring remains an area for improvement. Given UFH’s high-risk profile, lapses in APTTR monitoring could directly compromise patient safety.
The audit points to several key actions. Staff education should be strengthened to ensure timely APTTR monitoring and appropriate dose adjustment. Handover processes must be improved so that monitoring continues consistently across shifts. Pharmacists should play a greater role in supporting safe UFH use by helping to complete timely VTE risk assessments, advising on prescribing and dose adjustments, interpreting APTTR results, and establishing electronic reminders to prompt monitoring at the correct intervals.
Unfractionated heparin remains a cornerstone of inpatient anticoagulation therapy, but it demands meticulous oversight. This audit demonstrates that while prescribing and initiation are largely safe, monitoring must be improved to reduce risks.
By prioritising multidisciplinary collaboration, pharmacist leadership, and stronger monitoring processes, hospitals can ensure safer and more effective use of UFH for patients requiring anticoagulation.
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Sheena Patel and Clarissa Pui are Clinical Pharmacists at Chelsea and Westminster Hospital NHS Foundation Trust
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