What lung‑transplant status (e.g., status 1A, 1B, or 2) should be assigned to a patient with end‑stage irreversible lung disease who is refractory to optimal medical, surgical, and rehabilitative therapy and meets standard eligibility criteria?

Lung Transplant Status Assignment for End-Stage Irreversible Lung Disease

Patients with end-stage irreversible lung disease who are refractory to optimal medical, surgical, and rehabilitative therapy and meet standard eligibility criteria should be assigned transplant status based on the Lung Allocation Score (LAS) system, which replaced the previous Status 1A/1B/2 classification in 2005. 1

Understanding the Current Allocation System

The historical Status 1A, 1B, and 2 classification system is no longer in use for lung transplantation in the United States. The LAS system now determines priority based on:

• Waitlist urgency (risk of mortality without transplant) combined with post-transplant survival probability 1
• Disease-specific prognostic factors with coefficient factors assigned to four diagnostic categories 1
• Individual patient characteristics including geographic location, height, blood group, and preformed antibodies 1

Disease-Specific Listing Criteria

For COPD Patients

• List immediately if BODE index >7, FEV₁ <15-20% predicted, or three or more severe exacerbations in the preceding year 2
• Refer for evaluation if BODE index 5-6, PaCO₂ >50 mmHg, and/or PaO₂ <60 mmHg 2
• Elevated pulmonary arterial pressure with progressive deterioration represents a specific indication 3

For Idiopathic Pulmonary Fibrosis

• List based on diffusion capacity decline, progressive disease despite optimal medical management, severe functional impairment with oxygen dependency, and deteriorating physiologic course 2
• Post-transplant 5-year survival rates of 50-56% support listing 2

For Cystic Fibrosis

• List based on disease-specific criteria with post-transplant survival showing 85% at 1 year and 45% at 5 years 2

For Bronchiectasis

• List if age ≤65 years with FEV₁ <30% and significant clinical instability, or rapid progressive respiratory deterioration despite optimal medical management 2

Critical Timing Considerations

Early referral to a transplant center is essential given the scarcity of donor organs and prolonged waiting times, with the goal of listing patients early enough to avoid extreme disability or pre-transplant death. 2 Patients should be referred when they meet referral criteria but listed only when they meet the more stringent listing criteria. 4

Risk Stratification for Listing

• 6-minute walk distance <250 meters is an independent predictor of mortality and should prompt urgent listing consideration 5
• The decision to list involves risk analysis of mortality during the projected waiting period versus likely mortality following transplant 6
• Overall 5-year survival for lung transplantation ranges from 50-60% 3

Common Pitfalls to Avoid

Do not delay referral until patients are too sick to transplant. Approximately 90% of patients are referred at an advanced stage when they already meet listing criteria, which may be too late. 5 Early referral allows time for:

• Screening and treatment of reversible contraindications - 52.4% of referred patients have absolute or relative contraindications, though most are modifiable 5
• Patient education and decision-making - Lower socioeconomic status patients are less likely to accept transplant, requiring more time for counseling 5
• Active management of comorbidities during the waiting period 7

Practical Application

The selection process for lung transplantation follows the same criteria whether for first-time transplantation or re-transplantation. 8 Patients must meet ISHLT criteria specific to their underlying disease (COPD, IPF, pulmonary arterial hypertension, pulmonary alveolar proteinosis, etc.). 8, 2

Bilateral lung transplantation demonstrates superior long-term survival (5-year survival 57.3% vs 47.4% for single lung) especially in patients younger than 60 years. 3