Apneic diffusion oxygenation and continuous flow apneic ventilation. A review.

Area of Science:

• Physiology
• Evolutionary Biology
• Respiratory Medicine

Background:

• Oxygen's dual role as essential for life and a cellular poison necessitates evolutionary adaptations.
• Transition from aquatic continuous breathing to terrestrial intermittent breathing likely evolved to manage higher atmospheric oxygen levels.
• Mammalian oxygen uptake can be sufficient via apneic diffusion oxygenation (ADO) and continuous flow apneic ventilation (CFAV).

Purpose of the Study:

• To explore the evolutionary pressures leading to intermittent breathing.
• To highlight the potential of ADO and CFAV in mammalian oxygen uptake.
• To evaluate CFAV as a viable alternative in artificial ventilation.

Main Methods:

• Review of evolutionary adaptations in breathing patterns from aquatic to terrestrial life.
• Analysis of physiological mechanisms of oxygen uptake in mammals, including ADO and CFAV.
• Comparison of conventional mechanical ventilation techniques with high-frequency ventilation and oscillatory methods.

Main Results:

• Intermittent breathing may serve as a protective mechanism against high atmospheric oxygen tensions.
• Mammals demonstrate adequate oxygenation through ADO and CFAV.
• High-frequency ventilation (60-400 breaths/min) and high-frequency oscillation (up to 40 Hz) represent advanced artificial ventilation strategies.

Conclusions:

• The evolution of intermittent breathing is linked to managing oxygen toxicity.
• ADO and CFAV are effective methods for oxygen delivery in mammals.
• CFAV warrants further investigation as a promising alternative for artificial ventilation.