Impaired bronchial healing after lung donation from non-heart-beating donors.
BACKGROUND
Bronchial viability after lung transplantation remains a concern. Modern preservation methods, surgical technique, and limited cold ischemic periods have decreased the frequency of bronchial complications. However, lungs procured from non-heart-beating donors are subjected to a mandatory period of warm ischemia. We investigated bronchial healing in a porcine survival model of left lung transplantation using organ procurement from non-heart-beating donors after a 60-minute period of warm ischemia.


METHODS
Fourteen adult domestic swine underwent left lung transplantation. All lungs were preserved with cold Euro-Collins flush and stored inflated at 4 degrees C. Control lungs (n = 5) were flushed, harvested, and stored for 2 hours before implantation. Experimental lungs (n = 9) were procured from non-heart-beating donors. These lungs were subjected to 60 minutes of warm ischemia before flush and harvest, followed by 2 hours of cold storage before implantation. After 21 days of immunosuppression with prednisone, azathioprine, and cyclosporine, pulmonary function was assessed. Bronchial viability was evaluated with bronchoscopy and, at autopsy, followed by histologic analysis.


RESULTS
Implantation time did not differ significantly between the control group and the experimental group (59.6 +/- 2.1 versus 64.4 +/- 2.9 minutes, p = 0.24). Control swine exhibited no evidence of ischemic injury to the donor bronchus. In contrast, six of nine lungs procured from non-heart-beating donors showed evidence of ischemic bronchial injury (p = 0.031 versus control). Findings ranged from hypovascular edematous mucosa to necrosis and sloughing of the mucosa throughout the entire donor bronchial tree. The remaining three non-heart-beating donor lungs exhibited normal lung function and bronchial healing.


CONCLUSIONS
We conclude that 60 minutes of warm ischemia for lungs procured from non-heart-beating donors results in impaired bronchial viability with current preservation techniques. Thirty minutes of warm ischemia may be the acceptable limit for lung procurement from non-heart-beating organ donors.
Binns
O A
OA
Department of Surgery, University of Virginia Health Sciences Center, Charlottesville 22908, USA.
DeLima
N F
NF
Buchanan
S A
SA
Nichols
G E
GE
Cope
J T
JT
King
R C
RC
Marek
C A
CA
Tribble
C G
CG
Kron
I L
IL
D000818:Animals; D001980:Bronchi / Q000473:pathology / Q000503:physiopathology*; D006439:Hemodynamics; D007511:Ischemia / Q000503:physiopathology; D008168:Lung / Q000098:blood supply; D016040:Lung Transplantation / Q000379:methods / Q000473:pathology / Q000502:physiology* / Q000706:statistics & numerical data; D011013:Pneumonectomy / Q000379:methods; D011659:Pulmonary Gas Exchange; D011897:Random Allocation; D018709:Statistics, Nonparametric; D013552:Swine; D013997:Time Factors; D014019:Tissue Donors; D014022:Tissue Survival / Q000502:physiology; D014945:Wound Healing