Anticoagulated Elderly Head Injury with a Delayed Bleed
A 78-year-old woman is brought by her son 3 hours after a mechanical fall in the bathroom, during which she struck the back of her head on the tiled floor and lost consciousness for 'a few seconds'. She takes apixaban 5 mg twice daily for atrial fibrillation, bisoprolol and amlodipine; her last dose was 6 hours ago. She is alert and orientated (GCS 15), reports only mild neck discomfort and has not vomited. There is a 4 cm boggy occipital haematoma but no palpable skull step, and the neurological examination is normal, including fundoscopy. Blood pressure 148/82 mmHg, heart rate 68/min, SpO2 97%. eGFR was 62 mL/min/1.73m² at a clinic visit last month. The emergency department has 24-hour CT but no on-site neurosurgery; the neurosurgical unit is 3 hours away by road. She lives alone.
1. Do you image immediately, and do you give reversal agents now? Justify both answers.
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Image immediately; do not reverse empirically.
Imaging: she has a head strike with loss of consciousness, a boggy occipital haematoma, and therapeutic anticoagulation. Clinical decision rules such as the Canadian CT Head rule were derived and validated in patients not on anticoagulants and cannot be used to withhold imaging here. Anticoagulated patients have a markedly higher risk of intracranial haemorrhage and of delayed haemorrhage after a normal initial scan, so a CT is indicated regardless of a GCS of 15.
Reversal: reversal is not given for a well patient with no radiological haemorrhage. Andexanet alfa and prothrombin complex concentrate carry thrombotic risk (she has atrial fibrillation, so stroke and myocardial infarction are real hazards), and there is no evidence of benefit in the absence of bleeding. Reversal is triggered by intracranial haemorrhage, ongoing significant bleeding, or the need for urgent surgery. Note also that a normal INR does not exclude apixaban effect - do not use coagulation tests to reassure yourself.
Also avoid the trap of the 'normal CT, safe discharge'. She lives alone, is 78, anticoagulated, has had a head strike with transient loss of consciousness, and delayed bleeds can appear hours later. Admit for observation for at least 24 hours, with neurological observations, a repeat CT at 6-8 hours or sooner if anything changes, and clear instructions for the nursing staff about what to escalate. Document that her son understands the reason for admission.
2. At hour 7 she vomits and becomes drowsy, GCS 13. Repeat CT shows a 25 mm right frontal intraparenchymal haemorrhage with 6 mm midline shift and no hydrocephalus. Outline your management, including reversal and blood pressure targets.
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This is a life-threatening intracranial haemorrhage in a patient on a direct factor Xa inhibitor.
Airway and physiology first: call for senior help, apply oxygen, protect the airway if GCS continues to fall (GCS 8 or less, or inability to protect from vomiting), maintain normocapnia, normothermia and normoglycaemia, and avoid hypotension - a single episode of systolic BP below 90 mmHg worsens outcome.
Reversal: give andexanet alfa if it is available and approved locally (low dose for apixaban 5 mg twice daily), or four-factor prothrombin complex concentrate 50 units/kg if it is not. Do not wait for laboratory results. Do not use fresh frozen plasma as first-line therapy, and do not give platelets - they do not reverse direct oral anticoagulants.
Blood pressure: lower systolic BP to below 140 mmHg, smoothly and without dips, using a titratable IV agent such as nicardipine or labetalol with arterial monitoring. Avoid dropping below about 130 mmHg; hypoperfusion of the penumbra is harmful.
Neurosurgery: speak to the on-call neurosurgeon now, send the images, and arrange urgent transfer - the 6 mm shift with clinical deterioration is a surgical discussion even though this haematoma is intraparenchymal rather than extradural. Reverse and stabilise before transfer, and anticipate intubation for the journey. Repeat CT before transfer if any further deterioration. Do not give tranexamic acid as a substitute for reversal, and do not correct the platelet count unless there is a separate indication. Give her reversal agent before she leaves the department, not on arrival at the tertiary centre.
3. How would your approach change if she had been taking warfarin rather than apixaban, and what if she had been taking dabigatran?
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The principle is the same - reverse the specific agent - but the agents and the monitoring differ.
Warfarin: give intravenous vitamin K 5-10 mg plus four-factor prothrombin complex concentrate 25-50 units/kg, dosed according to INR and body weight, and recheck the INR at 15-30 minutes and again at 6-12 hours because vitamin K takes hours to act and the INR can rebound. Fresh frozen plasma is a poor substitute: it needs a large volume, takes time to thaw, and can overload an elderly heart. If the INR was previously stable and in range, also look for an alternative cause of the bleed (fall, hypertension, structural lesion).
Dabigatran: give idarucizumab 5 g intravenously (two 2.5 g vials) - it is a specific monoclonal antibody fragment and works within minutes. It is useless for apixaban or rivaroxaban; andexanet alfa and PCC have no meaningful effect on dabigatran. Dabigatran is renally cleared, so check renal function, and note that the drug can be removed by dialysis in refractory cases, which is a consideration in a patient with advanced kidney disease.
For all three, the rest of the plan is identical: urgent imaging, blood pressure control to systolic below 140 mmHg, neurosurgical discussion, and reversal before transfer. The common error is treating all 'blood thinners' as interchangeable - giving PCC for dabigatran, or platelets for any of them, wastes time and gives false reassurance. Confirm the exact drug, dose and time of the last dose from the patient's own pack or the pharmacy record rather than from memory.