You are treating a patient with a dysrhythmia You are teaching your students about the phases of the cardiac action potential and emphasize the absolute refractory period as a means of preventing another action potential being generated Which factor is most important for this period?

A 45 year old builder attends with an elbow injury An x-ray confirms fracture of the medial epicondyle On examination there is hyperextension of the metacarpophalangeal joint and flexion of the interphalangeal joint of ring and little fingers.
Which nerve is most likely to be injured?

A 60 year old man with alcoholic liver cirrhosis and portal hypertension is brought to the ED because he has been vomiting blood Which vein is the most likely origin of his haematemesis?

A 20 year old woman has an incised wound over the angle of her jaw and you suspect damage to a branch of the facial nerve What action are you most likely to test to confirm your suspicion?

A 33 year old man presents with signs of sepsis. A venous blood gas is taken which confirms an elevated haematocnt level What best describes the normal range of haematocnt you expect to find in a healthy male of this age?