In Loving Memory of Erin OKeefe

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In Loving Memory of Erin OKeefe

• By Anna Seekatz, Sarah Brown,
• Angi Weston, Shelly Potter

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The Question

• Our pal Scott was climbing Pikes Peak and he
  found that he had to sit down three times on the
  way up. The last time was in the weather station
  where he glanced at the barometer which read
  450mmHg.
• Predict the cardiovascular changes that have
  taken place by the time Scott has reached the
  weather station.

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Whats going on as Scott climbs

• The diffusion of oxygen across the alveolar
  membrane depends on the partial pressure of
  oxygen in the air vs. the partial pressure of
  oxygen in the blood.
• As Scott gains altitude, oxygen is decreasing in
  the atmosphere which means that the gradient for
  diffusion of oxygen is decreasing as well.

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Summary of Gas Transport
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Alveolar PO2 is the partial pressure of oxygen in
the alveolar sacsWould this increase, decrease
or stay the same as Scott climbs?

• Alveolar PO2 would DECREASE

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2. PO2 arterial is the partial pressure of
oxygen within arterial bloodWould Scotts PO2
arterial increase, decrease, or stay the same?

• PO2 arterial would DECREASE

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O2 saturation arterial is the amount of oxygen
molecules bound to hemoglobin within arterial
blood Would this increase, decrease, or stay
the same?

• Arterial saturation of O2 would most likely
• STAY THE SAME

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Hemoglobin Dissociation Curve
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4. O2 venous saturation is the amount of oxygen
molecules bound to hemoglobin in the veinsWould
O2 venous saturation increase, decrease, or stay
the same?

• O2 venous saturation would DECREASE

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Tidal volume is the volume of air that moves
during inspiration or expiration Would tidal
volume increase, decrease, or stay the same?

• Tidal volume would INCREASE

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PCO2 arterial is the partial pressure of CO2 in
arteries Would PCO2 increase, decrease, or stay
the same?

• PCO2 would DECREASE

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Arterial pH is the concentration of hydrogen ions
in arteries (which is inversely related to
concentration of CO2)Would arterial pH
increase, decrease, or stay the same?

• Arterial pH would INCREASE

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Our Analogy
Plaque says" Erected in memory of Erin
O'Keefe-Daughter of John and Nora O'Keefe who
was eaten by Mountain Rats in the year
1876"Photo courtesy Tom Jamison Family