When climbing Mount Everest, the man's circulatory and respiratory systems undergo several changes to provide oxygen to his working muscles: His heart rate increases to pump more oxygen-rich blood while diastolic blood pressure drops and systolic pressure and blood volume rise. His breathing also deepens and his ventilation rate increases to deliver more oxygen to his bloodstream. Upon reaching the peak, tissue hypoxia occurs due to less oxygen in the thin air. His heart works harder, pumping more blood, while lung conditions involve faster, deeper breathing and increased pulmonary artery pressure to compensate for the lower oxygen levels.

1. A healthy person,
male, aged 20-30
years old wants to
climb Mount
Everest. Describe
the changes in his
circulatory and
respiratory system
when he:
a) is climbing the
mountain (hint:
strenuous activity)

2. a) Climbing the mountain: CIRCULATORY SYSTEM
An aerobic
activity. The
man needs
more oxygen.
Heart rate
increases.
Heart pumps
more blood.
Diastolic
pressure drops.
The man
breathe deeper.
Systolic blood
pressure rises
and blood
volume
increases.

3. a) Climbing the mountain: RESPIRATORY SYSTEM
Body’s need for fresh
oxygen increases.
The rate of respiration also
increases to facilitate the
delivery of oxygen to the
blood stream and working
muscles.
Ventilation rate responds
accordingly.
Concentration of CO2
increases.
Why??
The metabolic by products of exercise
build up as a result of cellular respiration,
and the amount of carbon dioxide in the
system also increases to act as a buffer
against these acidic by products.

4. b) When he reached the highest peak: CIRCULATORY SYSTEM
At high altitudes, the decrease in barometric
pressure reduces the amount of oxygen initially
available in the environment.
Tissue hypoxia, as a result of the significant
decrease in oxygen availability in inspired air.
A reduction in plasma volume caused by increased
respiratory, urinary, and cutaneous losses.
The initial cardiovascular response to altitude is
characterized by an increase in cardiac output.
Pulmonary artery pressure increases.
The hypoxic ventilatory response persists for the
sea-level resident who remains at high altitude.

5. b) When he reached the highest peak: RESPIRATORY SYSTEM
• Everyone breathes faster and deeper
(hyperventilates) at high altitude.
• The lung response to acute altitude
exposure is mainly hyperventilation
which, together with elevated heart
rate, aims at achieving an adequate
supply of oxygen to the tissues.
• Besides the compensatory response,
other mechanisms affect lung
physiology during hypoxic exposure:
the increase of pulmonary artery
pressure and endothelial permeability.
• In simple words, lungs conditions at
higher altitudes is faster, deeper
breathing because of an increased
oxygen demand, and carbon dioxide
must be expelled.

6. Symptoms of High Altitude Sickness
Loss of appetite, nausea, or vomiting
Fatigue or weakness
Feeling dizzy, light-headed or faint
Disturbed sleeping patterns
Confusion and disorientation
Impaired memory
Mood swings

7. How to treat High Altitude Sickness??
Early diagnosis is important. Acute mountain sickness is easier to treat
in the early stages.
The main treatment for all forms of mountain sickness is to climb down
(descend) to a lower altitude as rapidly and safely as possible. You
should not continue climbing if you develop symptoms.
Extra oxygen should be given, if available.
People with severe mountain sickness may need to be admitted to a
hospital.
Acetazolamide (Diamox) may be given to help you breathe better. It can
help reduce mild symptoms. This medicine can make you urinate more
often.
Drink plenty of fluids and avoid alcohol when taking this drug. This
medication works best when taken before reaching a high altitude.

8. would it make any
difference if the
climber is a female?
Yes. Because female’s
metabolism and body
strength is lower than the
males.