

Hypoxaemic hypoxia – caused by low P aO 2. Hypoxia is therefore classified in terms of failure of one or more of the processes above: The following conditions must be fulfilled for cells to utilise O 2 for aerobic metabolism:Īdequate arterial O 2 tension ( P aO 2) – blood leaving the lungs must be adequately oxygenated.Īdequate O 2 -carrying capacity – blood must have an adequate haemoglobin (Hb) concentration.Īdequate cardiac output (CO) and arterial flow ensures that the O 2 carried by Hb reaches the tissues.Īdequate mitochondrial function – the cells must be able to use O 2 effectively for aerobic metabolism. This can result from either a failure of O 2 delivery or a failure of O 2 utilisation. Hypoxaemia refers specifically to reduced P aO 2. Hypoxia refers specifically to the situation in which tissues are unable to undergo aerobic metabolism.
