An illustration showing four different stages of gangrene, including one (Fig. 4 top right) caused by an obstacle to the return of the venous blood due to heart disease. Symptoms may include a change in skin color to red or black, numbness, pain, skin breakdown, and coolness. The feet and hands are most commonly involved.
complications of Hypoxia 
complications of Hyperventilation
complications of Aspiration pneumonia
complications of Pulmonary embolism
complications of Bronchiolitis
complications of Carbon monoxide poisoning
complications of Air embolism
complications of Sepsis