How is a lung allocation score (LAS) calculated?

The following medical information is used to calculate a lung allocation score (LAS):
  • Forced vital capacity: The lung function test that measures the maximum amount of air people can breathe out after breathing in as deeply as possible. This amount may be lower in people with lung disease.
  • Pulmonary artery pressure: The pressure the heart must generate to pump blood through the lungs. This pressure may be high in some people with serious lung disease.
  • Oxygen at rest: The amount of oxygen needed at rest to maintain adequate oxygen levels in the blood. People with severe lung disease often need additional oxygen.
  • Age: The candidate's age at the time lungs are offered.
  • Body mass index (BMI): The ratio of a person’s weight to height that, when interpreted with other medical test results, helps to evaluate health status.
  • Diabetes: May be a predictor of health status in some people with lung disease.
  • Functional status: Measures the effects of lung disease on someone’s ability to perform routine daily tasks.
  • Six-minute walk: Transplant candidates are asked to walk as far as they can in six minutes. The distance walked is a measure of functional status.
  • Assisted ventilation: Using a ventilator to assist breathing may be a measure of disease severity and may affect success after a transplant.
  • Pulmonary capillary wedge pressure: The pressure blood returning to the heart from the lungs must overcome. This pressure can become increased when the heart is not pumping effectively.
  • Serum creatinine levels: A measure of kidney function, high creatinine levels reflect impaired kidney function, sometimes associated with severe lung disease.
  • Diagnosis: Research has shown that urgency among people needing a lung transplant and success following a lung transplant vary among people with different lung diseases. Therefore, for every lung transplant candidate, diagnosis factors into the calculation of the lung allocation score.
  • PC02: The current PC02 and change in PC02 are both considered in the lung allocation score calculation. When the lung's ability to exchange oxygen and C02 becomes impaired, the PC02 level can become increased.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.