Patients who are receiving long-term anticoagulation and are due for surgery, or other invasive procedures, may need to have their anticoagulants stopped temporarily to allow the procedure to be performed safely.
In some circumstances, interrupting anticoagulation for a defined period carries minimal risk. But some patients are at high risk of thrombotic complications, with even a short suspension.
Certain patients benefit from substituting their long-term oral anticoagulant with an injected short-acting preparation, the most established of which being heparin1. Historically, patients have been converted to intravenous (IV) heparin, which requires an inpatient admission for infusion for up to three days before surgery.
In January 2013, at Leeds Teaching Hospitals NHS Trust, the implementation of pharmacist-led bridging clinics was led by a specialist surgical pharmacist within a wider team of healthcare professionals. The service was launched following a review of the number of patients being admitted pre-operatively for IV heparin and the number of patients whose surgery was cancelled for reasons relating to anticoagulation.
The review showed that there were 6–15 admissions per month and each patient was admitted three days prior to surgery. Historical data show that the cancellation rate of surgeries owing to inappropriate anticoagulation management was between 6 and 20 surgeries per month.
The pharmacist-led bridging clinics were designed with the support of the trust’s haematology services, surgical leads and anaesthetics colleagues. Nurses working in the pre-assessment clinics were taught how to identify and assess patients at risk of a thrombotic event when not on therapeutic anticoagulation. These teaching sessions were run by the pharmacy team; this learning came alongside the trust’s guidelines for pre-operative anticoagulation, which were launched in conjunction with the introduction of the pharmacist-led bridging clinics.
All patients leave their appointment with an individual anticoagulation plan, a supply of subcutaneous LMWH and a sharps bin
Patients are now seen seven to ten days prior to their admission, following protocolled referrals from pre-assessment nurses. Rather than receiving IV heparin as an inpatient, patients receive bridging with tailored-dosage subcutaneous low-molecular weight heparin (LMWH) as an outpatient. They also receive education on their individual need for conversion to a subcutaneous LMWH and are assessed for their ability to self-inject. We frequently teach patients’ relatives and carers to support them in this to reduce the need for appointments with practice and district nurses. All patients leave their appointment with an individual anticoagulation plan, a supply of subcutaneous LMWH and a sharps bin.
These clinics run on an outpatient basis and are supported by the current pre-assessment teams, including the healthcare assistants, who take blood samples, and administration teams, who run the booking of the clinics and collate medical notes. They have been introduced to an already established pathway; staff working in the clinical area are empowered and there is minimal disturbance for other patients attending for pre-assessment appointments.
In the clinic’s first year, 127 patients attended, saving 381 bed days. Of the 127 patients, 7 had surgeries cancelled on the day they were scheduled; 6 for reasons other than anticoagulant management, and 1 due to a patient’s elevated international normalised ratio.
We used a patient questionnaire to understand the impact of this work on patient experience. Feedback was very positive; all patients stated that they would recommend the service to their friends and family, and preferred it to an admission for IV heparin. However, two patients raised the issue of having to return to the hospital for an additional clinic appointment. We have since been working with GPs to support the supply of subcutaneous LMWH for patients who struggle to return to the hospital.
The clinics, and guidelines that support practice, were reviewed in 2017 following new evidence and updated national guidance2,3,4. The clinics now provide patients and clinicians with advice on the post-operative introduction of oral anticoagulation, including a recommended loading regimen of oral anticoagulation, which is individually tailored pending the patient’s pre-surgical anticoagulation dosing schedule. This reduces the time that a patient’s anticoagulation is not optimised and the time a patient is required to inject LMWH.
In the six years since the service was introduced, more than 3,168 bed days — more than 500 bed days per year, on average — have been generated as a result of reduced length of stay. The service is currently available only to patients undergoing formal pre-assessment who are scheduled for a general anaesthetic. But we plan to extend these services to patients attending for procedures under a local anaesthetic, for example, biopsies, endoscopy and other radiology procedures, in the future.
Sophie Blow is advanced clinical pharmacist, peri-operative medicines optimisation, Peri-operative Anticoagulant Bridging Clinic Services and Acute Surgery, St James’s University Hospital, Leeds Teaching Hospitals NHS Trust
- Douketis J, Crowther M & Kovacs M; The Thrombosis Interest Group of Canada. Perioperative management of patients who are receiving warfarin or antiplatelet therapy. 2009. Available at: http://www.just.edu.jo/DIC/ClinicGuidlines/Perioperative%20Management%20of%20Patients%20who%20are%20Receiving%20Warfarin%20or%20Antiplatelet%20Therapy.pdf (accessed August 2019)
- Douketis JD, Spyropoulous AC, Kaatz S et al. Perioperative bridging anticoagulation in patients with atrial fibrillation. N Engl J Med 2015;373(9):823–833. doi: 10.1056/NEJMoa1501035
- Schulman S, Hwang HG, Eikelboom JW et al. Loading dose vs. maintenance dose of warfarin for reinitiation after invasive procedures: a randomised trial. J Thromb Haemost 2014;12(8):1254–1259. doi: 10.1111/jth.12613
- Keeling D, Tait RC & Watson H; The British Committee of Standards for Haematology. Peri-operative management of anticoagulation and antiplatelet therapy. Br J Haematol 2016;175(4):602–613. doi: 10.1111/bjh.14344