Urgent extraction in an anticoagulated patient with a borderline INR
A 68-year-old man attends for urgent assessment of tooth 46. The tooth has a deep distal carious lesion, is tender to percussion, and has a 6 mm buccal periodontal pocket with suppuration; it is judged non-restorable. He has atrial fibrillation and takes warfarin 5 mg daily; his last INR, taken two days ago, is 3.8 (target 2.0–3.0). His blood pressure is 156/92 mmHg and HbA1c is 8.4%. He takes bisoprolol and metformin; he has no history of bleeding, liver disease, or falls. He reports no fever, dysphagia, or floor-of-mouth swelling, and there is no facial swelling. He is flying abroad in five days and asks for the tooth to be removed today. The clinic has 4% articaine with 1:100,000 adrenaline, 2% lidocaine with 1:80,000, suture material, haemostatic agents, and tranexamic acid mouthwash. There is no on-site haematology service.
1. Is it appropriate to extract tooth 46 today? Justify your decision using his INR and clinical findings, and state what you would do if the INR were 4.6 with the same presentation.
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Today's extraction is not clearly safe, and I would defer it by 24–48 hours. For dental extractions, an INR below about 3.5–4.0 is generally accepted without reversing warfarin, provided local haemostatic measures are used; many units use 4.0 as the ceiling. His INR of 3.8 sits at that ceiling, and it was measured two days ago, so it may have drifted. More importantly, this is not a simple extraction: a 6 mm pocket with suppuration implies bone loss, possible root fracture, and a surgical approach with more bleeding. He has no spreading infection, dysphagia, or systemic upset, so there is no emergency justification for operating at the limit of safety. I would speak to his anticoagulation clinic or physician, arrange a repeat INR within 24 hours of the procedure, and aim to operate when it is ≤3.5. If the INR were 4.6: do not extract in this setting. Refer to oral and maxillofacial surgery with haematology support; if there were spreading infection, admit for intravenous antibiotics and discuss reversal (vitamin K, prothrombin complex) with haematology. Never stop warfarin abruptly.
2. Describe your anaesthetic and haemostatic plan for the extraction visit, including what you would prescribe.
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Anaesthesia: avoid an inferior alveolar nerve block if possible, because a deep block in an anticoagulated patient can produce a pterygomandibular space haematoma that is difficult to compress and may compromise the airway. Use 4% articaine with 1:100,000 adrenaline as a buccal infiltration plus lingual infiltration, with slow injection and aspiration; if a block is unavoidable, use it after weighing the risk. Maximum articaine dose is 7 mg/kg (about 500 mg, or 7 cartridges for a 70 kg adult), but I would use the minimum that works. For surgical access, a small intraligamentary supplement may be enough.
Haemostasis: raise a minimal flap only if needed, use atraumatic extraction, curette the socket, place a haemostatic agent (oxidized cellulose or gelatin sponge), and secure with a figure-of-eight suture. Apply pressure with a gauze pack for 10 minutes. Prescribe 0.12% chlorhexidine or 4.8% tranexamic acid mouthwash 10 mL four times daily for two to three days, starting the day after surgery, not on the day. Avoid NSAIDs; use paracetamol. Warn about bleeding, give written advice, and ensure a contact number.
3. He asks whether he can stop warfarin for a few days 'to be safe', and whether he should fly five days after the extraction. How do you respond?
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Stopping warfarin is more dangerous than the bleeding risk of a dental extraction. Without anticoagulation his stroke risk from atrial fibrillation is substantial, and rebound hypercoagulability can occur. Warfarin should only be interrupted on the instruction of his anticoagulation team, and for dental surgery bridging with low-molecular-weight heparin is rarely needed and is itself associated with bleeding. I would explain that the plan is to control bleeding locally, not to stop his medication, and that his INR will be checked close to the appointment.
Regarding the flight: if the extraction is uncomplicated and haemostasis is secure, flying five days later is reasonable, but I would advise him to have the procedure at least 48–72 hours before travel, to avoid alcohol and vigorous rinsing, and to carry the written advice and a contact number. If he has a bleeding episode, he must seek dental or emergency care before flying. I would also flag his HbA1c of 8.4%: poor glycaemic control increases infection and delayed healing, so I would liaise with his diabetes team and consider deferring elective surgical extraction until control improves.