Question

Explain the biochemical steps of what happens when someone falls into a swimming pool and is submerged for a period of 2 minutes.

Why do we sometimes administer Sodium Bicarbonate to patients during the resuscitation of cardiac arrest?

Answer 1

1.

When a person is drowned in water, there can't be breathing possible. When there is no breathing happening, te brain will not get sufficent O2 for getting energy as it requires to undergo cellular respiration continuously. Brain cells do not undergo anaerobic respiration and hence get effected immediately. In about 5 minutes the lack of O2 and energy affects the brain functioning and the person will die due to lack of O2.

But , if a person is submerged only for 2 minutes, it results in increased CO2 levels in the blood due to inability to exhale CO2 from the body. CO2 combines with water to form H2CO3 or carbonic acid. Since it is unstable, it breaks in to H+ and HCO3- ions. Release of H+ ions will make the blood more acidic than normal. Normal blood pH ranges from 7.35 to 7.45. If the pH goes below 7.35, it will have ill consequences in the body.

2.

During cardiac resuscitation, NaHCO3 (sodium bicarbonate) is given to reduce blood acidosis. Lack of O2 supply to the tissues will result in blood acidosis. It is a serious condition in the body. So by giving proper amount of NaHCO3, the acidosis of blood is normalized and blood pH is brought to normal range. It is important to maintain blood pH as it allows the body metabolism to go on properly. Disturbance in blood pH, enzymes do not work properly effecting the body metabolism.