chapter  6
35 Pages

Perioperative influences on respiratory homeostasis

The chemical reactions that comprise ‘internal’ respiration may be summarized as follows:

6O2 C6H12O6 ⎯⎯⎯⎯→ 6CO2 6H2O ( Energy) oxygen glucose carbon water (6.1)

dioxide

Whilst production of carbon dioxide is normal, excess gas must be excreted to prevent an accumulation of harmful carbonic acid arising from the reaction of the gas with water:

CO2 H2O ⎯⎯→ H2CO3 ⎯⎯→ H HCO3-

carbon water ←⎯⎯

carbonic ←⎯⎯

hydrogen bicarbonate (6.2) dioxide acid ions ions

As time elapses high levels of carbon dioxide in the blood would also cause an increase in heart rate and irritability of the heart muscle. There might also be an increase in the blood pressure and blood flow to the brain, eventually leading to coma and respiratory depression.