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Refine Lung Data Fields

eye iconAt a glance

Current policy

The Lung Allocation Score (LAS) is used to rank candidates for lung offers and is made up of different clinical factors of a lung transplant candidate. This includes factors such as the transplant candidate’s body mass index (BMI) and what they have been diagnosed with. Changes to the lung allocation score (LAS), “Updated Cohort for Calculation of the Lung Allocation Score (LAS),” were approved winter 2020 at the OPTN Board of Directors Meeting and are planned for implementation in the fall of 2021.

Supporting media


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Proposed changes

This proposal clarifies data entry and the impact of specific diagnoses for LAS as it relates to the changes pending fall 2021 implementation. These proposed changes are related to the use of body mass index (BMI), pulmonary fibrosis, and bronchiolitis in the LAS.

  • Body Mass Index (BMI)
    • Add separate date collected fields for the candidate’s values for height and for weight
    • Update policy to only require weight to be updated every six months
  • Diagnoses
    • Consolidate diagnosis option for “secondary pulmonary fibrosis” into “Pulmonary fibrosis: other specify cause”
    • Clarify that the diagnoses “pulmonary fibrosis: other” and “COVID-19: pulmonary fibrosis" use the same coefficient in the LAS calculation
    • Clarify that the diagnoses “obliterative bronchiolitis” and “constrictive bronchiolitis” use the same coefficient in the LAS calculation
  • Pulmonary Artery (PA) Pressure
    • Clarify that if the value for “mean PA pressure” is missing for a candidate, the value will be assumed to be 30 or less
  • Label consistency
    • Align names of three diagnosis codes between policy and UNetSM

Anticipated impact

  • What it's expected to do
    • Improve the consistency and accuracy of lung candidate data
    • Change certain candidates LAS scores
  • What it won't do
    • Change how the LAS is calculated


  • Data consistency
  • Record maintenance

Terms to know

  • Lung Allocation Score: In the OPTN lung allocation system, every lung transplant candidate age 12 and older receives a lung allocation score. The LAS is used with blood type and the distance between the candidate and the donor hospital to determine priority for receiving a lung transplant. The score is made up of factors that help determine a candidate’s waitlist urgency and post-transplant survival.
  • Body Mass Index (BMI): A measure of body size, calculated as weight in kilograms divided by height in meters squared.
  • Pulmonary Fibrosis: A lung disease that results in lung tissue being damaged and scarred.
  • Constrictive Bronchiolitis/Obliterative Bronchiolitis: A disease that results in obstruction of the smallest airways of the lungs due to inflammation.
  • Coefficient: A number used to multiply a variable.
  • Click here to search the OPTN glossary

eye iconComments

NATCO | 05/27/2021

The North American Transplant Coordinators Organizations (NATCO) supports this policy proposal and appreciates the work of the OPTN Lung Transplantation Committee to clarify data entry and the impact of specific diagnoses for LAS as it relates to the changes pending the fall 2021 implementation. We support the recommendation to add separate date collected fields for the candidate’s values for height and for weight regarding BMI. We also support the use of the same coefficient for “pulmonary fibrosis: other” and “COVID-19: Pulmonary fibrosis” in the LAS calculation; the use of the same coefficient for “obliterative bronchiolitis” and “constrictive bronchiolitis”; and the assumption of a mean PA pressure of 30 or less, when a value is missing.

American Society of Transplantation | 05/26/2021

The American Society of Transplantation is supportive of the proposal. The Society offers the following comments for the Lung Transplantation Committee’s consideration. BMI: Proposed changes: 1. Replacing the current single date field for height, weight, and BMI with distinct date fields for height and weight 2. Specifying that only the weight is required to be updated every 6 months in order to keep the BMI current The AST agrees with the proposed change of replacing the current single date for H, W, and BMI with distinct dates of height and weight and that the weight is the only value that is required to be updated every 6 months. However, the BMI issue is vital to pediatrics. These patients’ BMIs change regularly because of both height and weight. With that in mind, having discrete fields for height and weight date collected makes sense. The one issue that remains unclear to us is the frequency with which the pre-transplant team will need to check height in pediatric patients. The proposal seems to suggest that only weight will be updated every six months. In children, not having both weight and height updated could lead to an artificially low BMI over time. Accordingly, we suggest also updating height in the pediatric population every six months. In one addition, we recommend that the substituted BMI, which currently default to 100 kg/m 2 if value is missing, should be defaulted to a more realistic value. This calculation is inserting the least beneficial value (as opposed to “normal”). Please see in Table 10-1 below. (included on PDF copy submitted) Diagnosis of Pulmonary Fibrosis: Proposed Changes: 1. Removing the diagnosis option of “secondary pulmonary fibrosis” 2. Utilizing the same coefficient when a candidate’s diagnosis is pulmonary fibrosis: other and COVID-19: pulmonary fibrosis. The AST agrees with this proposed change of specifying that the pulmonary fibrosis “other specify cause” and COVID -19 fibrosis received the coefficient adjustment to the LAS. Of note on page 6, the document states that “idiopathic pulmonary fibrosis” currently is in Group A, which is in error. IPF is actually classified as Group D. See below: “In OPTN policy, Table 10-3: Waiting List Mortality Calculation: Covariates and their Coefficients lists a waiting list coefficient for “pulmonary fibrosis: other specify cause (Diagnosis Group D only).” The Committee proposes specifying that the “Pulmonary fibrosis: other specify cause” and “COVID-19: Pulmonary fibrosis” receive the coefficient adjustment to LAS for waiting list mortality. These changes would make a distinction between “idiopathic pulmonary fibrosis,” which does not receive the adjustment, and all other pulmonary fibrosis diagnoses, which would. This is in alignment with the current placement of “idiopathic pulmonary fibrosis” in Group A and all other pulmonary fibrosis diagnoses in Group D. “ Bronchiolitis Proposed Change: 1. Clarifying that the coefficient currently used when a candidates’ diagnosis is “obliterative bronchiolitis” is also used when the candidate’s diagnosis is “constrictive bronchiolitis” The Society agrees with this proposed change as it will make the coefficient adjustment apply for the post-transplant survival calculation to both diagnoses. Sarcoidosis Proposed Change: 1. Clarifying that when PA pressure is missing from a candidate with sarcoidosis, the candidate will be placed in group A and given the same coefficient adjustment as candidates with a mean PA pressure of 30 mmHg or below. The AST agrees with this proposed change to make it more transparent that if a mean pulmonary pressure value is missing that this variable would be treated as 30 or below and the candidate will be placed in Group A. While this is the current practice, we agree the proposed clarification decreases confusion. 2. Updating three labels for three diagnoses The AST agrees with this proposed change of labels for these three diagnoses to align with current terminology.

View attachment from American Society of Transplantation

OPTN Transplant Coordinators Committee (TCC) | 05/25/2021

The OPTN Transplant Coordinators Committee (TCC) thanks the OPTN Lung Transplantation Committee for the opportunity to review their public comment proposal. TCC believes this proposal will improve the system for a clearer and more concise method of data sharing. This proposal is exceptionally important for Transplant Coordinators as it ensures the waitlist is as accurate as possible.

American Society of Transplant Surgeons (ASTS) | 05/14/2021

The American Society of Transplant Surgeons (ASTS) generally supports this policy proposal and appreciates the work of the OPTN Lung Transplantation Committee in identifying areas in need of clarification. With respect to BMI (height and weight), we recommend regular, non-single point data collection as this component can be dynamic during the listing period. Clarifications proposed on the diagnosis of “obliterative bronchiolitis,” the imputation of a mean PA when those values are absent, and the new diagnosis labels are reasonable. ASTS is not in support of removing the diagnosis option of “secondary pulmonary fibrosis.” However, if the PF coefficient is similar for “secondary” or “other,” that would be considered reasonable.

dawn freiberger | 05/10/2021

I strongly support this as it will make things less confusing particularly the weight and height issue.

Anonymous | 05/07/2021

I agree these clarifications need to be made. I agree High FLow Nasal Cannula ( usually can go up to 60 Land 100%) needs to be better defined. Use of NIPPV ( serious in COPD but very serious in an ILD now hypercarbic pt) needs refinement as well

Anonymous | 04/30/2021

I support the proposal including efforts to improve consistency. I think the committee should take this opportunity to also improve consistency in the following fields: - Supplemental O2 requirement - Should this be patient reported or measured? If measured, there should be strict guidelines on how it should be measured to ensure consistency/equity between programs and patients. Should a resting saturation be measured first on room air, and O2 then titrated (if needed) to achieve goal > 88%? If so how long off O2 prior to resting saturation measurement? Etc.. Perhaps using ATS 6MWT guidelines as a starting point. A related but slightly different question is what to do for a hospitalized patient on high flow nasal cannula - should the flow or the FO2% be entered? - Assisted ventilation - A patient requiring chronic CPAP (or BiPAP) for obstructive sleep apnea is of course much different than one using it for chronic or acute on chronic respiratory failure. Should a program be able to enter CPAP for a patient with chronic obstructive sleep apnea? These definitions should be clearly and explicitly defined.

Deedre Boekweg | 04/27/2021

This will be helpful to define data entry