Extra questions from tests

Question 1

Explain the direction of blood flow in a patent ductus arteriosus

Answer 1

left to right, blood goes from the aorta back into the the pulmonary trunk down its pressure gradient. -> thus LV overload and eventual failure

Question 2

In the fetus which has the highest vascular resistance, pulmonary or systemic?

Answer 2

pulmonary

Question 3

What marker is looked for in MI?

Answer 3

the CARDIAC form of troponin I

Question 4

Describe the principal behind a defibrillator

Answer 4

Depolarises the heart to stop all electrical activity and allow it to re-coordinate

Question 5

Describe the action of lidocaine

Answer 5

Selectively blocks Na channels in the open or inactivated state and thus blocks damaged cardiac tissue in depolarised state

Question 6

What causes a forceful displaced apex beat?

Answer 6

LV hypertrophy

Question 7

Long QT syndrome can predispose to ventricular tachycardia. Explain how profound tachycardia can cause a fall in arterial BP

Answer 7

Rapid HR impairs ventricular filling -> decreased BP

Question 8

Mitral and tricuspid murmurs are loudest at the ____, whilst aortic and pulmonary ones are loudest at the _____

Answer 8

Apex/base