Mr. Bruce Bogtail (BB) is a 24 year old medical student who has recently moved to Mexico City (2240 metres above sea level) for his internship. As he examines the lab report of his first patient, Pablo, he notices the red blood cell (RBC) count is above the reference range levels.
a) Using your knowledge of red blood cell function, determine what physiological problems an elevated RBC count may cause for Pablo .
b) Describe the potential physiological benefits of this increased red blood cell count.
c) Outline the respiratory adjustments Bruce will have to make in his own breathing (e.g. minute volume, arterial PaCO2 and Hb saturation levels) in order to live comfortably at this higher altitude both in the short and longer term.
Mr. Vin Phuong (VP) is a 44 year-old chef who recently migrated to Australia from Vietnam and feels very stressed. He is a heavy smoker (40 x 8mg cigarettes/day) and due to his long working hours, only achieves approximately 4-5 hours of sleep a night. During the day he regularly consumes two energy drinks and four (4) cups of coffee in order to stay awake. He was recently diagnosed with high blood pressure.
a. In terms of normal physiology, explain how the body regulates blood pressure.
b. Explain how stress, smoking and energy drinks/coffee can increase blood pressure. Explain how the stress related increase in blood pressure may be beneficial in the short term. In your answer, name the hormones involved and describe the vascular responses.
c. Describe the impact that elevated blood pressure would have on the circulatory system in terms of preload, afterload and peripheral resistance.