Timing of heparin and thrombus formation in donor lungs after cardiac death.

BACKGROUND: Heparin is routinely administered to brain-dead donors before cardiac arrest, although it is not universally allowed for donation after cardiac death (DCD) donors due to concerns that death may be hastened. The lack of heparin may lead to thrombosis and compromised graft function. We evaluated the impact of timing of heparin administration and thrombi formation in a DCD pig model. METHODS: Eight domestic adult pigs were administered systemic heparin (30,000 IU): four prior to cardiac arrest through intravenous injection (prearrest heparin) and four after cardiac arrest via injection into the right atrium followed by open cardiac massage (postarrest heparin). Pigs were euthanized with potassium chloride and a minimum of 5 minutes of cardiac silence allowed before organ procurement. Lungs were flushed with antegrade and retrograde Perfadex, and pulmonary preservation solution effluent was evaluated for gross thrombi. Organs were fixed in formalin, sagittally sectioned, and evaluated by a pulmonary pathologist blinded to treatment. RESULTS: Antegrade and retrograde flushes demonstrated no significant thrombi. Gross pathologic evaluation revealed no occlusive central thrombi. Scant peripheral thrombi were detected in both treatment groups. No microscopic thrombi were noted in either treatment group. CONCLUSIONS: Delayed heparin administration after cardiac death does not affect thrombus formation in an animal model of lung procurement after cardiac death. Concern about clinically significant thrombosis occurring when heparin is not given before cardiac arrest appears unfounded. These findings suggest that DCD lungs can be used regardless of antemortem heparin administration.

Pediatric donor lungs for adult transplant recipients: feasibility and outcomes.

BACKGROUND: There is a limited experience using pediatric organs for adult lung transplantation (LTx), with size matching the major concern. We reviewed our experience transplanting pediatric donor lungs into adult recipients with endpoints of post-LTx complications and overall patient survival. METHODS: From 2/1990 to 12/2007, 609 adults underwent primary LTx at our institution. Thirty-eight (6.2%) patients underwent LTx with organs from pediatric donors (≤16 years). Of these, median donor age was 13 years (range: 7 to 16) and median recipient age 55 (range: 24 to 66). Endpoints analyzed included size matching accuracy, airway and pleural complications, time to extubation, intensive care unit (ICU) and hospital lengths of stay, as well as survival. RESULTS: Gross undersizing of the donor lung was present in 2/38 (5.3%) and of the donor bronchus in 11/38 (29%). Five patients (13%) experienced a major postoperative airway complication. Thoracentesis prior to discharge was necessary in 4/38 (11%) patients and chest tube reinsertion in 10/38 (26%) for pleural effusion. Median time to extubation was 2 days. ICU and hospital lengths of stay were 6 and 16 days, respectively. Kaplan-Meier survival at 30 days, 1 year, 3 years, and 5 years post-transplant was 89%, 74%, 63%, and 55%. CONCLUSIONS: Despite sizing concerns, transplantation of pediatric lungs into adult recipients is feasible. Size mismatch may predispose to higher rates of airway and pleural complications. Hospital course and overall survival appear comparable to adult-to-adult LTx, and concerns over size matching should not preclude pediatric organ use for adult candidates.