Normothermic Regional Perfusion Prior to Lung Transplantation: Is Quicker Always Better?
Presented During: Welcome Reception and Poster Competition | Sponsored by: TransMedics
Ohio State Wexner Medical Center
Columbus, OH
United States - Contact Me
Post-doctoral research fellow at The Ohio State University Wexner Medical Center under Dr. Bryan Whitson, MD PhD.
Friday, September 20, 2024: 5:00 PM - 6:30 PM
Omni King Edward Hotel
Description
Objective: To determine the association of prolonged normothermic regional perfusion (NRP) evaluation on the outcomes of lung transplant recipients.
Methods: The United Organ Sharing Database was queried from 1/1/2019 to 3/31/2024 for recipients who received lungs from donation after circulatory death (DCD) donors who were evaluated for heart transplantation using NRP. NRP donation was determined if a donor heart was evaluated for transplantation and had a circulatory standstill to aortic cross-clamp time (warm ischemic time [WIT]) > 40 minutes). Recipients were then stratified into short evaluation (SE, 40-90 minutes) or long evaluation (LE, >90 minutes). The groups were then analyzed with comparative statistics, and Kaplan-Meier method for survival. Next, a 1:1 nearest neighbor propensity match (caliper 0.2, all standard mean differences [SMD]<0.1) based on select donor and recipient characteristics was performed to further compare SE and LE. The matched groups analyzed with comparative statistics and survival was assessed with the Kaplan-Meier method.
Results: 76 patients were stratified into the LE group, and 151 patients stratified into the SE group. The median WIT for the LE group was 125.5 minutes and 57 minutes for the SE group. In terms of recipient characteristics, significantly fewer patients in the LE group were placed on pre-operative ECMO (0% [0/76] vs 7.9% [12/151], p=0.027). Regarding donor characteristics, there were no significant differences in smoking history (LE 6.7% [5/75] vs SE 8.2% [12/146], p=0.89) and BMI (LE M:26.4 vs SE M:25.9, p=0.94). Conversely, the donors in SE group were significantly older (median [M]: 39 vs M: 33, p=0.003) and had a significantly higher PaO2:FiO2 (PF) ratio (M:439 vs M:407, p=0.038). Post-operatively the SE group had significantly longer ischemic time (M:8.4 hours vs M:6.6 hours, p=0.034) and length of stay (LOS) (M:28 days vs M:20 days, p=0.017). Though not significant, the SE group had a higher incidence of dialysis (14.2% [20/141] vs 5.7% [4/70], p=0.11), primary graft dysfunction grade 3 (PGD3) (23.2% [35/151] vs 15.8% [12/76], p=0.26). In-hospital mortality (LE 4.5% [3/67] vs SE 9.2% [12/130], p=0.36) and short-term survival for the unadjusted groups were not significantly different (p=0.065, Figure A). Following matching, two well matched groups (SMD<0.1) of 44 patients in each group were formed. Post-operatively, the SE group had significantly longer ischemic time (M: 8.5 hours vs 6.1 hours, p=0.003). Additionally, though not significant, the SE group had longer LOS (M:26 days vs M:19 days, p=0.25) and increased incidences of PGD3 (22.7% [10/44] vs 15.9% [7/44], p=0.59). In-hospital mortality (LE 4.8% [2/42] vs SE 9.1% [4/43], p=0.69) nor short-term survival was significantly different between the matched groups (p=0.23, Figure B).
Conclusions: Though there were few statistically significant differences between the LE and SE groups (in both matched and unmatched analysis), those in the SE group had increased rates of peri-operative morbidity as compared to the LE group. Additionally, the LE group had about ~4% lower in-hospital mortality as well ~12-14% lower short-term mortality. Further research is needed to clarify NRP evaluation times prior to lung transplant, given the association with reduced survival and shorter evaluation.
Authors
Martin Walsh (1), Vivienne Pham (2), Ervin Cui (3), Divyaam Satija (4), Matthew Henn (5), Kukbin Choi (6), Nahush Mokadam (6), Asvin Ganapathi (5), Doug Gouchoe (7), Bryan Whitson (4)
Institutions
(1) Ohio State Wexner Medical Center, Burr Ridge, IL, (2) The Ohio State University College of Medicine, Columbus, OH, (3) The Ohio State Wexner Medical Center, Columbus, OH, (4) Ohio State University, Columbus, OH, (5) Ohio State University Wexner Medical Center, Columbus, OH, (6) The Ohio State University Wexner Medical Center, Columbus, OH, (7) The Ohio State Medical center and Nationwide Childrens Hospital, Columbus, OH
Methods: The United Organ Sharing Database was queried from 1/1/2019 to 3/31/2024 for recipients who received lungs from donation after circulatory death (DCD) donors who were evaluated for heart transplantation using NRP. NRP donation was determined if a donor heart was evaluated for transplantation and had a circulatory standstill to aortic cross-clamp time (warm ischemic time [WIT]) > 40 minutes). Recipients were then stratified into short evaluation (SE, 40-90 minutes) or long evaluation (LE, >90 minutes). The groups were then analyzed with comparative statistics, and Kaplan-Meier method for survival. Next, a 1:1 nearest neighbor propensity match (caliper 0.2, all standard mean differences [SMD]<0.1) based on select donor and recipient characteristics was performed to further compare SE and LE. The matched groups analyzed with comparative statistics and survival was assessed with the Kaplan-Meier method.
Results: 76 patients were stratified into the LE group, and 151 patients stratified into the SE group. The median WIT for the LE group was 125.5 minutes and 57 minutes for the SE group. In terms of recipient characteristics, significantly fewer patients in the LE group were placed on pre-operative ECMO (0% [0/76] vs 7.9% [12/151], p=0.027). Regarding donor characteristics, there were no significant differences in smoking history (LE 6.7% [5/75] vs SE 8.2% [12/146], p=0.89) and BMI (LE M:26.4 vs SE M:25.9, p=0.94). Conversely, the donors in SE group were significantly older (median [M]: 39 vs M: 33, p=0.003) and had a significantly higher PaO2:FiO2 (PF) ratio (M:439 vs M:407, p=0.038). Post-operatively the SE group had significantly longer ischemic time (M:8.4 hours vs M:6.6 hours, p=0.034) and length of stay (LOS) (M:28 days vs M:20 days, p=0.017). Though not significant, the SE group had a higher incidence of dialysis (14.2% [20/141] vs 5.7% [4/70], p=0.11), primary graft dysfunction grade 3 (PGD3) (23.2% [35/151] vs 15.8% [12/76], p=0.26). In-hospital mortality (LE 4.5% [3/67] vs SE 9.2% [12/130], p=0.36) and short-term survival for the unadjusted groups were not significantly different (p=0.065, Figure A). Following matching, two well matched groups (SMD<0.1) of 44 patients in each group were formed. Post-operatively, the SE group had significantly longer ischemic time (M: 8.5 hours vs 6.1 hours, p=0.003). Additionally, though not significant, the SE group had longer LOS (M:26 days vs M:19 days, p=0.25) and increased incidences of PGD3 (22.7% [10/44] vs 15.9% [7/44], p=0.59). In-hospital mortality (LE 4.8% [2/42] vs SE 9.1% [4/43], p=0.69) nor short-term survival was significantly different between the matched groups (p=0.23, Figure B).
Conclusions: Though there were few statistically significant differences between the LE and SE groups (in both matched and unmatched analysis), those in the SE group had increased rates of peri-operative morbidity as compared to the LE group. Additionally, the LE group had about ~4% lower in-hospital mortality as well ~12-14% lower short-term mortality. Further research is needed to clarify NRP evaluation times prior to lung transplant, given the association with reduced survival and shorter evaluation.
Authors
Martin Walsh (1), Vivienne Pham (2), Ervin Cui (3), Divyaam Satija (4), Matthew Henn (5), Kukbin Choi (6), Nahush Mokadam (6), Asvin Ganapathi (5), Doug Gouchoe (7), Bryan Whitson (4)
Institutions
(1) Ohio State Wexner Medical Center, Burr Ridge, IL, (2) The Ohio State University College of Medicine, Columbus, OH, (3) The Ohio State Wexner Medical Center, Columbus, OH, (4) Ohio State University, Columbus, OH, (5) Ohio State University Wexner Medical Center, Columbus, OH, (6) The Ohio State University Wexner Medical Center, Columbus, OH, (7) The Ohio State Medical center and Nationwide Childrens Hospital, Columbus, OH