Spinal Anaesthesia for Complete Molar Pregnancy With Biochemical Thyrotoxicosis and Ventricular Ectopy

Gestational trophoblastic disease (GTD) presents unique anaesthetic challenges due to the combined risks of haemorrhage, cardiopulmonary compromise, and endocrine dysfunction. Complete hydatidiform mole is frequently associated with markedly elevated human chorionic gonadotropin (β-hCG) concentrations, which may result in biochemical or clinical thyrotoxicosis through thyroid-stimulating hormone receptor activation. Anaesthetic technique selection during uterine evacuation remains contentious. General anaesthesia (GA) is often favoured because it allows airway control and rapid escalation in the event of massive haemorrhage, yet it may provoke significant sympathetic activation, which is undesirable in thyrotoxic states or in the presence of ventricular arrhythmias. Conversely, spinal or regional anaesthesia avoids volatile agent uterine relaxation and airway manipulation, potentially reducing bleeding and allowing earlier recognition of complications (e.g., thyroid storm or cardiopulmonary distress), but requires meticulous prevention and treatment of sympathectomy-related hypotension. We describe the anaesthetic management of a 20-year-old primigravida at 16 weeks' gestation with a complete hydatidiform mole complicated by severe β-hCG elevation, biochemical thyrotoxicosis, and frequent premature ventricular complexes (bigeminy). Despite biochemical thyroid dysfunction, the patient remained clinically euthyroid, with no tachycardia and no clinical features of heart failure. The patient was haemodynamically stable and had preserved ventricular function. Following structured risk assessment, spinal anaesthesia was selected. Hypotension secondary to sympathetic blockade was proactively managed using a phenylephrine infusion to maintain arterial pressure while avoiding tachycardia. This case demonstrates that neuraxial anaesthesia can be a safe and physiologically appropriate alternative to GA in carefully selected patients with molar pregnancy, when endocrine status, cardiovascular reserve, haemorrhage risk, and institutional readiness for conversion to GA are rigorously assessed.