Sue Sanders
Elective Care Divisional Quality Board
May 2013
The New Oral Anticoagulants.
 Generic
 Trade
Dabigatran Rivaroxaban Apixaban
Pradaxa
Xarelto
Eliquis
Mode of Action
 Dabigatran (Pradaxa) is a thrombin inhibitor
 Rivaroxaban (Xarelto) and Apixaban (Eliquis) are
inhibitors of activated Factor Xa
 Warfarin is a Vitamin K antagonist. Factors II, VII, IX, X
NOACs Background
 2008
 Registered for the Primary prevention of VTE in adults
undergoing total hip and knee replacements.
NOACs Background
 2011
 Approved for the prevention of stroke and systemic
embolism in adults with non valvular atrial fibrillation
with one or more risk factors: previous stroke, TIA or systemic embolism
 left ventricular ejection fraction <40%
 Symptomatic heart failure
 Age >75
 Age<65 with diabetes mellitus, coronary artery disease or hypertension.
NOACs
 They are fast acting
(Tmax Dabigatran 30mins)
THEY DO NOT REQUIRE
MONITORING!
NOACs Half Life
Pradaxa
Xarelto
Eliquis
150mg BD
15 – 20mg OD
5mg BD
~ 13hours
5 – 9 hours
12 hours
Dependent on
Renal clearance
11-13 hours in
the elderly
Warfarin ½ life – 40 hours.
Dabigatran (Pradaxa) ½ life
Renal function
Estimated ½ life
(CrCl in ml/min)
Stop Dabigatran before elective surgery
High Risk or major
surgery
Standard risk
≥80
~13
2 days before
24 hours before
≥50 – <80
~15
2-3 days before
1-2 days before
≥30 – <50
~18
4 days before
2-3 days before
(>48 hours)
•80% renal excretion
•½ life can be significantly prolonged in patients with renal disease.
NOACs and coagulation parameters
Dabigitran
Rivaroxaban and Eliquis
TEST
PT
Prolonged slightly
APTT
Prolonged but in a non
linear fashion.
TT
Markedly prolonged (x10)
May be un-measureable
Prolonged to 15-33secs at peak
therapeutic levels
Prolonged up to x2 baseline
INR NOT SUFFICIENTLY SENSITIVE AND CANNOT BE USED
NOACs Reversal
 Evidence on reversal is patchy
 If severe bleeding occurs within 24 hours of a dose of :-
 Dabigatran – give FEIBA (Factor Eight Inhibitor Bypassing
Activity and is an activated prothrombin complex concentrate)
50IU/kg IV(In the transfusion lab)
 Rivaroxaban and Eliquis – give Octaplex (nonactivated
prothrombin complex concentrate) 50IU/kg/IV (In the transfusion lab)
NOACs – so what’s the problem?
 A quantitative assessment of coagulation is not
possible.
 A qualitative assessment of coagulation is unreliable.
(e.g. Pradaxa – “an aPTT>2x upper limit of normal at trough
is associated with a higher risk of bleeding”.)
NOACs – So what’s the problem Part II?
 The plasma concentration of the drug (and therefore
the anticoagulation) will vary DAILY.
 There may be one peak and trough
(Rivaroxaban OD) or two (Dabigatran and Eliquis BD)
Warfarin – once stabilised the plasma concentration remains within 1
INR unit. e.g. 2 - 3
NOAC Plasma concentration
Dabigatran clearance of a 200mg dose
NOACs – So what’s the problem Part III?
 No definitive guidance on the management of these
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patients in relation to dental treatment.
The patient information leaflets of all 3 drugs give no
specific advice.
In relation to surgery, advice varies from “do exactly as your
Dr says” and “ you may need to stop”.
SPC in relation to surgery advises stopping at least 24 hours
pre-op (Rivaroxaban and Eliquis).
Following the renal clearance chart (Dabigatran)
NOACs – So what’s the problem Part IV?
Dear Dentist,
“Similar to warfarin, there may be some procedures
which, at the discretion of the dentist, can be carried
out with no discontinuation of therapy.”
Boehringer Ingelheim
Pradaxa
6th August 2012
NOACs Management of Dental Treatment
“Practical Guide Dabigatran
Guidance for use in Particular Situations.”
Heidbuchel et al
Belgium
Sept 2011
NOACs Heidbuchel et al 2011
Recommendations
 Dabigatran should not necessarily be discontinued for the extraction of 1-3
teeth, paradontal surgery, abscess incision or implants.
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Procedure should be 12 hours after the last dose (8am -> surgery 8pm)
Least possible trauma
Wound should be sutured
Patient can only leave when bleeding completely stopped.
Tranexamic Acid M/W 5% QDS 5/7
(clot stabilisation only)
Oral and written instructions
Patient to contact dentist in case of bleeding that does not stop spontaneously.
Dentist to be available after hours
NOACs Heidbuchel et al 2011
Recommendations
 If the decision is to discontinue Dabigatran should be
stopped 24h prior to extraction and resumed once
haemostasis is achieved.
 For more extensive intervention the patient should be
referred to a maxillofacial surgeon!
NOACs – So what’s the Problem Part V?
 There has been an exponential rise in prescribing
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15 patients Dec 2012
Over 150 patients May 2013
400 patients are eligible
Rivaroxaban will be the drug of choice.
No new patients will be Rx Dabigatran
Michelle Grundy
Anticoagulation Service Waters Meeting HC
NOACs The Future?
Warfarin 3p each
Rivaroxaban £1.71 each
Apixaban £2.10 each
Dabigatran £ 1.26 each
Monitoring
No Monitoring
NOACs – the solution?
Awareness and vigilance.
Guidelines for management of NOAC patients
- minor procedures
- major procedures elective (+/- bridging)
- emergency haemorrhage protocol
Audit
NOACs Draft Guidelines
 Safe.
 Universal.
 Suitable for both Primary, Tier 2 and Secondary care.
 Clear for the clinician.
 Clear and easy for the patient to follow.
NOACs Draft Guidelines
(Proposed )
1. Omit NOAC on the morning of surgery.
2. Usual local measures / judicious extractions etc.
3. Recommence NOAC the following day.
For simple elective procedures such as extractions, apicetomies, biopsies, soft
tissue surgery, and some fractures excluding orbital floor injuries.
NOAC Guidelines
For emergency surgery, or more major
procedures including Head and Neck, orbital
floor surgery, Parotid / submandibular gland
surgery, soft tissue surgery in the neck etc –
haematology advice should be sort on a case by
case basis, particularly in respect of
recommencing NOACs in situations where post
op bleeding could be problematic.
NOACs Draft Guidelines
 Low Clot Risk patients.
PE/DVT >6 anticoagulated >6 weeks
Atrial fibrillation
Peripheral vascular disease.
 High clot risk patients.
 PE/DVT within last 6 weeks (surgery should be deferred if possible)
 Recurrent PE/DVT
 Prosthetic heart valves
 Antiphospholipid syndrome
 Patients with active cancer
 AF patients with a previous stroke or TIA
NOAC Draft Guidelines
 Complies with the Trust Draft Guidelines for
Anticoagulation of Adult Patients (consultation)
 “Dabigatran, rivaroxaban, apixaban and other newer oral
anticoagulants (NOACs) have quick onset of action so do
not require a switch over to heparin for high clot risk
patients as required with Warfarin. This also means that
high and low clot risk patients are dealt with in the same
way – i.e. for elective procedures simply stop the drug and
allow 24 hours to elapse before surgery commences. In
patients with renal failure longer may be required
(Dabigatran).
NOACs can be recommenced 24 hours post op.”
NOAC Draft Guidelines
 OMFS proposed guidelines have been approved by:
 Dr Mark Grey
Consultant Haematologist
 Dr Ambar Basu
Chair, Hospital Thrombosis Committee
NOAC Audit Proposal
 Prospective audit of all NOAC patients presenting for
surgery – extractions, biopsies, I & D, trauma, H & N,
across the Unit.
 Audit any post extraction haemorrhage patients
presenting via A & E and the treatment room at
Blackburn.
Thank you