Perioperative Anticoagulation and Risk Assessment: Building a Bridge Over a STREAM

TL;DR

This paper introduces a mnemonic called STREAM to help doctors decide when to use bridging anticoagulation during surgery, reducing risks of bleeding and blood clots.

Contribution

The novel contribution is the STREAM mnemonic, which simplifies decision-making for perioperative anticoagulation bridging.

Findings

STREAM highlights high-risk scenarios requiring bridging anticoagulation.

The mnemonic includes recent stroke, severe thrombophilia, and mechanical heart valves.

STREAM aims to optimize anticoagulation while minimizing bleeding and clot risks.

Abstract

Perioperative care requires a comprehensive assessment of the risks of bleeding and thrombosis. The 2022 CHEST Guidelines offer an empirical foundation for customized treatment using clinical judgment and risk assessment based on CHA2DS2-VASC and HAS-BLED scores. Despite the ease of access to anticoagulation guidelines, decision-making remains challenging, particularly when determining the necessity of bridging therapy with unfractionated or low-molecular-weight heparin. To facilitate this decision, we provide a mnemonic, STREAM, that highlights high-risk situations that require bridging. These include recent stroke or transient ischemic attack, severe thrombophilia, rheumatic valvular disease, recent venous thromboembolism, atrial fibrillation with high CHA2DS2-VASC scores, and mechanical heart valves. This mnemonic offers physicians a methodical approach to optimize perioperative anticoagulation control while minimizing the risk of hemorrhage and thrombosis.

Tables

Table 1. Suggested Risk Stratification for Patient-specific Periprocedural Thromboembolism

Risk Category	Mechanical Heart Valve	Atrial Fibrillation (A)	Venous Thromboembolism
High	(M) Mitral valve with risk factors for strokeb	CHA2DS2VASc score ≥7 or CHADS2 score of 5 or 6	Recent (<3 mo and especially 1 mo) VTE (E)
(>10%/year risk of ATE	Caged ball or tilting disc valve in mitral/aortic position …		Severe thrombophilia (T) (deficiency of protein C, protein S or antithrombin, homozygous factor V Leiden or prothrombin gene G20210A mutation or double heterozygous for each mutation, multiple thrombophilia’s)
or >10%/month risk of VTE)	Mechanical valve (M)	Recent (<3 month) stroke or TIA
	Recent (<3 month) stroke or TIA (S)	(R)Rheumatic valvular heart disease	Antiphospholipid antibodies Active cancer associated with high VTE riskc
Moderate	Mitral valve without risk factors for strokeb	CHA2DS2VASc score of 5 or 6 or	VTE within past 3-12 mo Recurrent VTE
(4%–10%/year risk of ATE or 4%–10%/month risk of VTE)	Bileaflet aortic valve with risk factors for strokeb		Non-severe thrombophilia (heterozygous factor V Leiden or prothrombin gene G20210A mutation) Active cancer or recent history of cancer
Low	Bileaflet aortic valve without risk factors for strokeb	CHA2DS2VASc score of 1-4 or	VTE >12 mo ago
(<4%/year risk of ATE or <2%/month risk of VTE)		CHADS2 score of 0–2 (and no prior stroke or TIA

Full text

INTRODUCTION

An essential component of perioperative management is the assessment of the patient's risk for thromboembolism, surgery/procedure-related bleeding, or the risk for a stroke/embolic phenomenon.^1,2^ The risk classification schemes in the 2022 CHEST Guidelines on Perioperative Antithrombotic Management aim to facilitate individualized patient care, but these guidelines are empiric and have not been prospectively validated.^3^

The guidelines are meant to be a starting point for risk assessment which also incorporates a clinical judgment pertaining to an individual patient's assessment for thromboembolism and bleeding. To bridge or not to bridge for a procedure with low-molecular-weight heparin or unfractionated heparin is justifiably determined by the thromboembolic risk versus the risk of bleeding, using the CHA2DS2-VASC score and the HAS-BLED.^4,5^

To Bridge Across a Turbulent Stream

Anticoagulation is frequently recommended when the risk is high (>10% events/year). Although the guidelines for anticoagulation decisions can be accessed online, we developed a mnemonic to determine when a ‘bridge’ is essential. A bridge can be built over a bay, a river, or a STREAM). Below are the conditions, which folks can easily remember, under which you should consider bridging with unfractionated or low-molecular-weight heparin, due to the significant risks of thromboembolism. "To bridge across a turbulent STREAM:"

(S) Stroke or TIA in the past 3-6 months(T) Thrombophilia (severe) example deficiency of protein C, protein S or Antithrombin 3, antiphospholipid antibodies, multiple abnormalities(A) Atrial fibrillation with CHA2DS2-VASC score of 5 or 6(R) Rheumatic valvular heart disease(E) Embolism/VTE in the last 3 months(M) Mechanical heart valve: any mitral valve prosthesis; any caged ball or tilting-disc aortic valve prosthesis