Severe Aortic Stenosis and a Hip Fracture on Recent Ticagrelor
An 82-year-old woman (62 kg) falls and sustains a displaced femoral neck fracture. History: severe aortic stenosis (aortic valve area 0.7 cm², mean gradient 48 mmHg, LVEF 55%), hypertension, and paroxysmal atrial fibrillation. She takes ticagrelor (last dose 26 hours ago; her cardiologist added it after a recent stent), metoprolol, and atorvastatin. She is in pain with HR 96, BP 158/84 mmHg, and SpO2 94% on 2 L nasal cannula. Surgery is scheduled in 10 hours. The cardiologist has documented "cleared for surgery," and the surgeon requests spinal anesthesia. Labs: Hb 104 g/L, platelets 190 × 10⁹/L, creatinine 110 µmol/L. She is frail and lives alone.
1. Assess her perioperative risk and identify which factors are modifiable before surgery.
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Risk: the combination of severe AS (AVA 0.7 cm², gradient 48 mmHg), urgent hip fracture surgery, antiplatelet therapy, and frailty places her at high risk for perioperative hypotension, myocardial ischemia, and mortality. Fracture surgery delays increase complications, so the goal is optimization within hours, not days.
Modifiable factors:
- Pain and sympathetic drive: HR 96 is undesirable in AS; treat pain with a fascia iliaca block and titrate metoprolol to HR 60–80.
- Volume status: assess for dehydration; maintain preload, which a stiff ventricle depends on.
- Anemia: transfuse if Hb <80 g/L or if symptomatic/ischemic; 104 g/L does not mandate transfusion, but plan for blood availability.
- Antiplatelet timing: recent ticagrelor (26 hours) is a contraindication to neuraxial anesthesia-ASRA guidance is to stop ticagrelor 5 days before a neuraxial procedure. Surgery should not wait 5 days for a hip fracture, so the anesthetic plan must change rather than the surgical timeline.
- Electrolytes, glucose, temperature, and delirium risk all deserve correction and planning.
2. Compare spinal, general, and fascia iliaca block with sedation for this patient, focusing on AS hemodynamics and the antiplatelet issue.
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Spinal: a single-shot spinal produces a rapid sympathectomy and fall in systemic vascular resistance. In fixed AS, cardiac output cannot rise to compensate, so BP falls, coronary perfusion falls, and ischemia follows. A spinal is also contraindicated with ticagrelor on board 26 hours ago because of the epidural hematoma risk. If a neuraxial technique were chosen after adequate drug washout, it would have to be an incremental, low-dose technique with vasopressors immediately available.
General anesthesia: gives airway and hemodynamic control, permits an arterial line, and avoids the antiplatelet-neuraxial conflict. Risks are induction-related vasodilation and tachycardia; a slow, titrated induction (etomidate or careful propofol, opioid, phenylephrine infusion ready) is appropriate.
Fascia iliaca block: provides excellent analgesia without sympathectomy and reduces opioid demand, but does not anesthetize the hip joint itself. It is best used as an adjunct, not a sole anesthetic, for a displaced femoral neck fracture.
Recommended judgment: fascia iliaca block plus general anesthesia with an arterial line, invasive monitoring, and a phenylephrine infusion; defer neuraxial until ticagrelor has been off 5 days if a neuraxial technique is still desired.
3. State your hemodynamic targets and how you would treat a drop in BP to 70/40 mmHg after induction, explaining why each intervention is chosen in AS.
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Targets: maintain MAP ≥65–70 mmHg (or the patient's baseline), HR 60–80 in sinus rhythm, and stable preload; avoid tachycardia and any drop in systemic vascular resistance.
Treating 70/40 mmHg:
- Phenylephrine 50–100 mcg IV boluses, repeated and then infused. In AS, the afterload is what drives coronary perfusion; phenylephrine raises SVR and reflexively slows the heart, which is exactly what a fixed-output ventricle tolerates.
- Fluid 250 mL crystalloid bolus, because a hypertrophied ventricle needs adequate preload and the patient has been fasting.
- Deepen or lighten anesthesia as appropriate, and reduce volatile agent concentration if it is causing vasodilation.
- If refractory, epinephrine 5–10 mcg boluses or vasopressin 0.5–1 unit for vasoplegia; consider TEE to assess filling and contractility.
Avoid: isoflurane at high concentrations, nitroprusside, and any agent or maneuver producing tachycardia-all shorten diastolic filling time and reduce coronary flow. In AS, hypotension must be treated immediately, not observed; cardiac arrest carries a very poor prognosis.