Jessica Olah / Verywell
V/Q Mismatch Symptoms
V/Q mismatch develops as a chronic lung disease progresses.
Severe lung disease can cause profound symptoms even when V/Q mismatch is not a major issue.
you’re free to experiencewheezing, dyspnea, and fatigue with COPD.
Jessica Olah / Verywell
As the disease progresses, V/Q mismatch tends to worsen too, adding to symptoms.
A lung infection likepneumoniacauses fever, chest discomfort, and fatiguewhether you have V/Q mismatch or not.
If the infectionalsocauses V/Q mismatch, that can worsen fatigue.
Causes
Lung diseases typically affect airflow and blood flow in the lungs.
When disease in the lungs affects airflow and blood flow unequally, V/Q mismatch occurs.
Diseases that interfere with airflow in the bronchi or alveoli result in a decreased V/Q ratio.
Diseases that obstruct pulmonary capillary blood flow result in an increased V/Q ratio.
This is described as a decreased V/Q ratio because the ventilation is more severely affected than the perfusion.
An actual object can block a bronchus, which prevents air from passing through a part of the lungs.
This also results in a low V/Q ratio.
This can occur due to disease or blockage of the blood vessels in the lungs.
This is a blood clot in the legs or arms that travels to the lungs.
It can obstruct blood flow in a pulmonary vein, decreasing perfusion to a region in the lung.
It can effectively identify a V/Q mismatch.
The test involves two simultaneous parts.
This is completely safe.
Anormal V/Q ratiois around 0.80.
Roughly four liters of oxygen and five liters of blood pass through the lungs per minute.
A ratio aboveorbelow 0.80 is considered abnormal.Higher-than-normal results indicate reduced perfusion; lower-than-normal results indicate reduced ventilation.
Treatments may include medication,oxygen supplementation, and/or surgical intervention.
Pulmonary Embolus
Pulmonary embolus is treated with blood thinners.
Sometimes surgical embolectomy is needed to remove the blood clot.
Infection
An infection may require treatment withantibiotics.
Sometimes supplemental oxygen therapy can be helpful until the infection resolves.
Pulmonary Edema
Pulmonary edemais treated withdiureticsas well as supplemental oxygen.
Your V/Q ratio may improve as your condition improves.
Typically, your symptoms and the results of complementary tests should improve with treatment as well.
A Word From Verywell
Often, V/Q mismatch is a sign of lung disease.
Your V/Q scan results are used along with the results of your other tests to help guide treatment.
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