A woman who is 34 weeks pregnant is admitted to the obstetric ward. She has been monitored for the past few weeks due to pregnancy-induced hypertension but has now developed proteinuria. Her blood pressure is 162/94 mmHg.
Which one of the following antihypertensives is it most appropriate to commence?
Correct Answer C: Labetalol is first-line for pregnancy-induced hypertension.
Pre-eclampsia:
Pre-eclampsia is a condition seen after 20 weeks gestation characterized by pregnancy-induced hypertension in association with proteinuria (> 0.3g / 24 hours). Oedema used to be third element of the classic triad but is now often not included in the definition as it is not specific.
Pre-eclampsia is important as it predisposes to the following problems:
Risk factors:
Features of severe pre-eclampsia:
Management:
Which one of the following drugs causes shortening of the QT interval?
Correct Answer A: Digoxin causes shortening of the QT interval whilst the other four drugs cause QT prolongation.
Digoxin and digoxin toxicity:
Digoxin is a cardiac glycoside now mainly used for rate control in the management of atrial fibrillation. As it has positive inotropic properties it is sometimes used for improving symptoms (but not mortality) in patients with heart failure.
Mechanism of action:
Digoxin toxicity: Plasma concentration alone does not determine whether a patient has developed digoxin toxicity. The BNF advises that the likelihood of toxicity increases progressively from 1.5 to 3 mcg/l.
Features:
Precipitating factors:
*Hyperkalaemia may also worsen digoxin toxicity, although this is very small print.
A 45-year-old man is diagnosed with endocarditis of the aortic valve. He is treated with intravenous benzylpenicillin and gentamicin.
What is the most important ECG change to monitor for?
Correct Answer E: A prolonged PR interval could indicate the development of an aortic abscess, an indication for surgery.
ECG: PR interval
Causes of a prolonged PR interval:
*Hyperkalaemia can rarely cause a prolonged PR interval, but this is a much less common association than hypokalaemia.
A 25-year-old woman is brought to the Emergency Department by a friend. She developed palpitations around 30 minutes ago whilst drinking a cup of coffee. Her only past medical history of note is asthma and menorrhagia for which she uses a salbutamol inhaler and takes tranexamic acid respectively. The admission ECG shows a supraventricular tachycardia at a rate of 160 bpm. Vagal manoeuvres are unsuccessful.
What is the most appropriate next step in her management?
Correct Answer A: The administration of adenosine is contraindicated by her history of asthma. Verapamil should therefore be given.
Supraventricular tachycardia:
Whilst strictly speaking the term supraventricular tachycardia (SVT) refers to any tachycardia that is not ventricular in origin the term is generally used in the context of paroxysmal SVT. Episodes are characterized by the sudden onset of a narrow complex tachycardia, typically an atrioventricular nodal re-entry tachycardia (AVNRT). Other causes include atrioventricular re-entry tachycardias (AVRT) and junctional tachycardias.
Acute management:
Prevention of episodes:
A 37-year-old woman who was investigated for progressive shortness-of-breath is diagnosed with primary pulmonary hypertension and started on bosentan.
What is the mechanism of action of bosentan?
Correct Answer C: Bosentan - endothelin-1 receptor antagonist.
Primary pulmonary hypertension:
The classification of pulmonary hypertension is currently changing with the term idiopathic pulmonary arterial hypertension (IPAH) becoming more widely used.
Primary pulmonary hypertension (PPH, now IPAH):
Investigation:
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