ACC recommends various Warfarin +/- bridging Heparin plans 5 days prior to surgery, mainly depending on the risk of thromboembolism (TE).
Risks of thromboembolism (TE) by condition:
Chronic A-fib:
- Low Risk (<5%/yr): CHADS2 score 0-2 and no hx prior stroke or TIA.
-
Mod Risk (5-10%/yr): CHADS2 score 3-4 and no high risk condition.
-
High Risk (>10%/yr): CHADS2 score 5-6, or recent (within 3 mos)
stroke or TIA, or rheumatic valvular heart dz.
Mechanical Heart Valve:
- Low Risk (<4%/yr): bileaflet aortic valve prosthesis, no a-fib, no
stroke risk factors (HTN. DM, CHF, age 75). - Mod Risk (4-10%/yr):
bileaflet aortic valve prosthesis and one of: (1) a-fib; (2) prior
stroke or TIA; and (3) at least one stroke risk factor (HTN, DM, CHF,
age >75).
- High Risk (>10%/yr): one or more of: (1) any
mitral valve prosthesis; (2) any caged-ball or tilting disk aortic valve
prosthesis; and (3) recent (within 6 months) stroke or TIA.
Prior Venous Thromboembolism (VTE):
- Low Risk: VTE occurred > 12 months ago and no moderate or high risk issues/factors (see below).
- Mod Risk: VTE within the past 3 to 12 months, non-severe thrombophilic
conditions (heterozygous carrier of factor V Leiden mutation or
prothrombin gene mutation), recurrent VTE, or active cancer (treated
within 6 months or palliative).
- High Risk: recent (within 3
months) VTE or severe thrombophilic conditions (deficiency of protein C,
protein S or antithrombin; antiphospholipid antibodies; or multiple
thrombophilic abnormalities). Patients who have had prior VTE after
surgery might be considered high risk depending on the type of surgery
they are undergoing (and the associated thromboembolic risk) and
perioperative antithrombotic management should be individualized.
Stop Warfarin approx 5 days before surgery (1C). Allow INR to return to near normal. If INR still elevated (i.e. > 1.5) on day before surgery, low dose oral Vit K 1-2.5 mg is suggested.When surgical hemostasis is adequate, resume Warfarin 12-24 hours post-op (i.e. the evening after surgery or the next morning) (2C).
Stop
Warfarin appx 5 days before surgery (1C). Allow INR to return to near
normal. If INR still elevated (i.e. ≥ 1.5) on day before surgery, low
dose oral Vit K 1-2.5 mg is suggested.
Patients with moderate
thromboembolic risk are a difficult category. ACCP outlined how there is
particularly little clarity from the literature to guide the decision
whether to provide bridging therapy. They recommend that the decision be
made on a case-by-case basis balancing the details of thromboembolic
risk and surgical bleeding risk (2C). For instance, in procedures with
high bleeding risks (examples can be viewed on bottom of ‘High Risk TE’
section), one might be disposed against bridging therapy, while when
surgery has low bleeding risk and/or anticoagulation indications are
particularly strong, one may be disposed towards bridging therapy. If
one elects bridging therapy, follow the recommendations in the ‘High
Risk TE’ section. Without bridging, these patients are managed like low
risk patients, as described here and on the ‘Low Risk TE’ section.
When surgical hemostasis adequate, resume Warfarin 12-24 h post-op (i.e. the evening after surgery or the next morning).
There
is new evidence which should prompt reconsideration whether to bridge
those with moderate thromboembolic risk. Since the ACCP 2012 periop
anticoagulation guideline publication, three significant studies have
been published.
In the BRIDGE trial (Douketis NEJM 2015), 1,884
patients with A-Fib on Warfarin at moderate thromboembolic risk were
randomized to bridging or no bridging. Bridging prevented no thromboemb
events and increased major bleeding
In the RE-LY trial sub-study
analysis (Douketis Thromb-Haem 2015), a cohort study of 4,133 A-Fib
patients on Warfarin or Dabigatran with ≥ 1 CHADS2 risk factor received
bridging or no bridging. Bridging prevented no thromboemb events and
increased major bleed.
Finally, there was a systematic review
& meta-analysis of 34 studies (1 RCT) showing no benefit and
increased bleeding from bridging (Siegal Circ 2012).
Thus
it appears that the preponderance of evidence leans away from bridging
for the moderate risk group. Pay attention to the next ACCP updated
periop anticoagulation guidelines.
Stop
Warfarin approx 5 days before surgery (1C). Allow INR to return to near
normal. If INR still elevated (i.e. > 1.5) on day before surgery,
low dose oral Vit K 1-2.5 mg is suggested.
During temporary
interruption of Warfarin, give bridging anticoagulation with
therapeutic-dose SC LMWH or IV UFH. For bridging anticoagulation with
LMWH, administer the last dose of LMWH 24 h before surgery (2C) and make
that last preop LMWH dose approx half the regular full daily dose if
daily dosing regimen used. For bridging anticoagulation with
therapeutic-dose IV UFH, stop UFH approximately 4-6 h before surgery
(2C).
Post-op, there are two considerations for anticoagulation, resumption of Warfarin and bridging heparin.
When surgical hemostasis adequate, resume Warfarin 12-24 h post-op (i.e. the evening after surgery or the next morning) (2C).
Post-op
bridging heparin is trickier because of the risk of serious post-op
bleeding. ACCP recommends considering the anticipated bleeding risk and
adequacy of post-op hemostasis in individual patients to determine the
timing of LMWH or UFH resumption after surgery instead of resuming LMWH
or UFH at a fixed time after surgery in all patients. In patients
undergoing a surgical or invasive procedure, considered
non-high-bleeding-risk, resume LMWH or UFH regimen approximately 24 h
after (i.e., the day after) the procedure when there is adequate
hemostasis (2C).
High-bleeding-risk procedures are those in which
post-op bleeding is more likely or when such bleeding poses particularly
serious consequences. These procedures include (but are not limited
to):
– urologic surgery like TURB, bladder rsxn, or tumor ablation; nephrectomy, or kidney bx
– pacemaker or implantable cardioverter-defibrillator device placement
– colon polyp rsxn, typically of large and/or sessile polyps
– surgery in highly vascular organs, such as the kidney, liver, and spleen
– bowel rsxn in which bleeding may occur at the anastomosis
– major surgery with extensive tissue injury (e.g., cancer surgery, joint arthroplasty, reconstructive plastic surgery)
–
cardiac, intracranial, or spinal surgery, especially as small
pericardial, intracerebral, or epidural bleeds can have serious
consequences
Minor dental procedures (2 options):
–
continue Warfarin around the time of the procedure and coadminister an
oral prohemostatic agent (i.e. surgical glue, tranexamic acid mouthwash,
sutures, etc.); or
– stop Warfarin 2-3 days before procedure (2C).
Minor Dermatologic procedures:
– continue Warfarin and optimize local hemostasis (2C).
Cataract removal:
– continue Warfarin
In
patients receiving Warfarin who require rapid reversal of
anticoagulation (surgery planned within 12 hours), give fresh-frozen
plasma or another prothrombin concentrate in addition to Vit K 2.5 to
5.0 mg PO on slow IV-push. The coadministration of Vit K is necessary
because the elimination half-life of FFP, for example, is 4-6 hours,
meaning that the anticoagulant effect of onboard Warfarin will reemerge
hours later unless countered by Vit K.
For less rapid reversal of anticoagulant (surgery planned 18-24 hours), give Vit K 2.5 to 5.0 mg oral or slow IV-push.