Oxygen toxicity is the increased oxygen content in the tissues beyond certain level. It is also called oxygen poisoning.
It occurs because of breathing pure oxygen with high pressure of 2-3 atmospheres (hyperbaric oxygen). In this condition, an excess amount of oxygen is transported in plasma as dissolved form because the oxygen carrying capacity of hemoglobin is limited to 1.34 mL/g.
1. Lung tissues are affected first with tracheobronchial irritation and pulmonary edema.
2. The metabolic rate is increased in body tissues and the tissues are burnt out by excess heat. The heat also destroys cytochrome system leading to damage to tissue.
3. When brain is affected, first hyperirritability occurs. Later, it is followed by increased by muscle twitching, ringing in ears and dizziness.
4. Finally, the toxicity results in convulsions, coma and death.
Treatment : Hyperbaric Oxygen Therapy (HBOT)
References : Essentials of Medical Physiology,K Sembulingam and Prema Sembulingam.