Everyone Healthy Library
Atelectasis
Condition / disease reference page from the Everyone Healthy database.
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Connected health information
Explore this condition in a clear order
Linked signs and symptoms
7Each sign/symptom opens its own page and links back to related conditions.
Linked drugs / medications
0No linked drugs are listed yet.
Treatments, therapies and supportive options
14Grouped by treatment type. These are educational database links, not personal treatment recommendations. Evidence labels are shown only where stored in the EH database.
Medical therapy
5Lifestyle changes
2Alternative and complementary therapies
1Linked diagnostic tests and investigations
5These are pulled from both EH diagnostic-test link tables, including the older large test-link table.
Biological markers/agents
2This visual map shows biological markers/agents reported as increased or decreased with this condition. These are educational relationships only; test results must be interpreted by a qualified clinician because ranges vary by lab, method, age, sex and clinical context.
Often increased
0No markers in this group.
Often decreased
2- Oxygen Saturation (Arterial Blood, SaO2)Reference range exampleChild (0 - 16y): 95–100 %; Newborn (0 - 1month): 40–90 %Linked diagnostic testsOxygen Saturation Test (Arterial Blood, SaO2)
- Partial Pressure of Arterial Oxygen (PaO2)Reference range exampleChild (0 - 16y): 80–100 mm Hg; Newborn (0 - 1month): 60–70 mm HgLinked diagnostic testsPartial Pressure of Oxygen (PO2)
Introduction / full article
Atelectasis
Atelectasis
At a microscopic level, the lung is comprised of many tiny air sacs called alveoli. At the alveoli, gas exchange occurs: that is, oxygen from the air enters into the bloodstream, and carbon dioxide from the deoxygenated blood re-enters the atmosphere. For this to occur, the alveoli must remain open. They are usually held open by the presence of air within them, and supported by the lung’s natural elasticity.
Atelectasis is a state in which all or part of the lung collapses. The alveoli deflate, and gas exchange cannot occur. Atelectasis therefore decreases the oxygen content of the blood. The body is capable of compensating for minor atelectasis by constricting the blood vessels supplied by the damaged area. Blood flow to available alveoli therefore increases, and gas exchange can occur.
Atelectasis can be caused by a blockage within one of the airways that branch off eventually to form alveoli, due to an inhaled foreign substance, or a tumour. Alternatively, pressure from outside can compress the lung; this pressure can be caused, for example, by a large amount of fluid or gas in the abdominal cavity.