Altitude Sickness Part One

Circulatory System 

With an increase in elevation, the air becomes thinner and the need for more oxygen increases. Problems can arise when going from sea level to 4000 feet. Fort Collins, where I will be for the 10 days leading up to our departure on the Colorado Trail, is at an elevation of 4982 feet. The CT starts in Denver/Littleton at 5430 and within 80 miles ascends12,000 to with most of the trail staying above 10,000 feet. Without properly acclimatization, nausea, vomiting, headache and fatigue can occur. 

In the circulatory system, oxygen poor blood is pumped through veins to the heart then through the lungs to pick up oxygen before heading back to the heart again to be pumped through the rest of the body through arteries.

This can be a bit confusing to the untrained eye, but start with 11 where deoxygenated blood enters the right atrium of the heart, flows down to the right ventricle (1), out the pulmonary vein (2) (veins carry deoxygenated blood), to the lungs (3) to pick up oxygen and release carbon dioxide to be exhaled, back to the left atrium of the heart via pulmonary artery (4) (arteries carry oxygen rich blood) down to powerful left atrium (5) of the heart to be forcefully pumped out to the body via aorta (6) traveling through smaller and smaller vessels called capillaries that reach to all tissues in the body (7 and 8) before heading back up towards the heart as deoxygenated blood (9, 10 and 11) to start the process again. Each cycle takes approximately 30 seconds.  Image from www.blendspace.com

Every red blood cell (eyrthrocite) has somewhere between 240-300 million hemoglobin molecules which each have the ability to carry four oxygen molecules. One cycle of a given portion of blood can take approximately 30 seconds to complete. Only 5% of the oxygen content is lost on each cycle. On a side note, because of the eyrthrocytes ability to carry so much oxygen, the American Heart Association has deemed it more valuable to keep the heart pumping blood to the tissues via compressions than to introduce breaths into the victim.

Blood is composed of about 65% red blood cells which have about 240-300 million hemoglobin molecules capable of carrying four oxygen molecules each. Photo from http://rpi-cloudreassembly.transvercity.net/2012/11/05/forms-of-oxygen/

http://www.hematology.org/Patients/Basics/

http://www.becpr.org/facts_statistics.aspx

http://lsa.colorado.edu/essence/texts/heart.html

https://www.merckmanuals.com/professional/hematology-and-oncology/approach-to-the-patient-with-anemia/red-blood-cell-production

http://www.pbs.org/wnet/redgold/basics/bloodproduction.html

https://www.awesomestories.com/asset/view/Breathing-How-Oxygen-Travels-in-the-Body0

http://www.sallyosborne.com/Med%20Lecture-%20Transport%20Of%20Blood%20Gases.pdf

http://www.altitude.org/high_altitude.php

http://rpi-cloudreassembly.transvercity.net/wp-content/uploads/2012/11/hemoglobin.jpg