A drop of blood contains approximately 300,000 red cells. Each
milliliter of blood contains 2,500,000 red cells. In each of the red cells
there are about 250,000,000 molecules a hemoglobin. Each of those molecules
love to combine (chemically bond) with oxygen molecules. The hemoglobin in
the red cells bonds with the oxygen molecules that are moving from the lung
into the blood stream. The oxygen moves from the alveoli to the capillaries
because of the pressure differential of high pressure O2 in the lungs
to the lower pressure in the returning blood from the body. The oxygen is
then carried from the lungs to all cells in the body finally to be released
by the hemoglobin to various cells to keep them productive. Without hemoglobin's
tremendous means of transport the blood would have to travel 20 times faster
to carry the required oxygen in the plasma of the blood alone!
Hemoglobin loves carbon monoxide (CO) 300 times better
than oxygen. If you have carbon monoxide in your breathing air the hemoglobin
will combine with it rather than the oxygen. Once the hemoglobin becomes
carboxyhemoglobin it will not release the CO to the body. In effect, the
hemoglobin no longer functions as an oxygen transport agent. That contaminated
red cell will be taken out of service by the spleen. In effect your blood
stream will be systematically destroyed until death from lack of oxygen if
one continues to breathe a sufficient quantity of carbon monoxide.
Hemoglobin contains iron atoms in its molecular structure.
Iron compounds are very colorful. (Look at iron oxide or rust. It is really
a beautiful red color.) When hemoglobin has an oxygen molecule attached to
it the iron makes it a bright red color. When the oxygen is released the
color turns to a dark red. Blood changes its color! If a carbon monoxide
molecule is attached to the hemoglobin the iron combination creates a bright
pink color. The lips, fingernails, and other places in the body where the
blood comes close to the skin in a person poisoned by carbon monoxide makes
them look like a clown. When the hemoglobin is contaminated with carbon monoxide
it is called, "carboxyhemoglobin."
How do divers encounter carbon monoxide? How could it
get into their scuba tank? Poor compressor operation, poor filtration, and
/or a contaminated air source going into the compressor are the responsible
agents. If a compressor runs too fast it may get overheated causing a dieseling
effect. The oil in the compressor ignites creating carbon monoxide. Running
a compressor near the exhaust of an automobile, gasoline-powered lawn mower,
a smoking chimney, etc. can cause CO to enter the air supply. Compressor
filters are supposed to remove CO by changing it to CO2. If the filter is
overwhelmed or wet it may not do the job.
Breathing carbon monoxide contaminated air usually produces
a headache as a preliminary symptom. Dizziness, drowsiness, and unconsciousness
follow prior to death.
Incidentally, smoking 30 cigarettes each day results
in the smoker's blood maintaining a constant level of 10%
carboxyhemoglobin!
