Are Lung Allografts from Drug Overdose Deaths Safe to Use for Transplantation?

E. Klipsch¹, K. Shorbaji², B. Trang¹, D. Mann³, W. Blanding¹, B. Gibney¹, L. Paoletti¹, T. Whelan¹, A. Kilic³, K. Engelhardt^1
1Medical University of South Carolina, Charleston, South Carolina ²Medical University of South Carolina, Mount Pleasant, South Carolina ³MUSC, Charleston, South Carolina

Purpose: Deaths from drug overdose (DOD) increase annually, and although many are considered for organ donation, hesitation remains to accept these allografts as they have been shown to have some high risk features (1-3). We sought to assess trends in use of DOD allografts and describe contemporary recipient outcomes.

Methods: The United Network for Organ Sharing registry was used to identify all adult (≥ 18 years) isolated lung transplant recipients between January 2010 and June 2022. Recipient allografts from DOD donors were compared to allografts from donors who died from other causes. Primary outcomes were 30-day and 1-year mortality. Kaplan-Meier and multivariable Cox proportional hazards models were used for unadjusted and risk-adjusted analyses, respectively. Secondary outcomes included hospital length of stay, acute rejection, stroke, acute renal failure dialysis, ECMO status at 72 hours, and post-transplant ventilator support.

Results: This study included a total of 27,707 adult lung recipients, and 11.87% (3,288 recipients) received allografts from DOD donors. The volume of DOD recipients has increased from 3.95% of all lung transplants in 2010 (67 recipients) to 20.16% in 2022 (443 recipients) (p < 0.001). DOD allografts were more likely to be utilized at centers with a higher mean number of lung transplants per year (62.68 vs. 58.14, p< 0.001) and had longer cold ischemia times (5.76 vs. 5.52 hours, p< 0.001). As seen in Figure 1, DOD recipients had comparable 1-year survival rates relative to other recipients in unadjusted analysis (log-rank p=0.390). In a risk-adjusted analysis, DOD recipients had comparable 30-day and 1-year mortality [30-day: Hazard Ratio (HR)= 0.92 (0.72-1.19, p=0.536), 1-year mortality: HR= 1.03 (0.92-1.17, p=0.590)]. There were no clinically significant differences in secondary outcomes.

Conclusion: There has been increased utilization of DODs in lung transplantation in the last decade driven by increasing use at large volume centers. Longer cold ischemia times suggest these organs may be passed over by closer recipients. However, short- and long-term recipient outcomes were similar when compared to all other allografts. These results support the safety of using DOD lungs and argue for more liberal use of DOD allografts to decrease waitlist mortality.

Identify the source of the funding for this research project: No external funding was utilized for this research project.