The effect of ex vivo lung perfusion on microbial load in human donor lungs.

BACKGROUND: Ex vivo lung perfusion (EVLP) has emerged as a technique to potentially recondition unusable donor lungs for transplantation. Beneficial effects of EVLP on physiologic function have been reported, but little is known about the effect of normothermic perfusion on the infectious burden of the donor lung. In this study, we investigated the effect of EVLP on the microbial load of human donor lungs. METHODS: Lungs from 18 human donors considered unusable for transplantation underwent EVLP with a perfusate containing high-dose, empirical, broad-spectrum anti-microbial agents. Quantitative cultures of bacteria and fungi were performed on bronchoalveolar lavage fluid from the donor lung before and after 3 to 6 hours of perfusion. The identification of any organisms and changes in number of colony forming units before and after EVLP were assessed and anti-microbial susceptibilities identified. RESULTS: Thirteen out of 18 lungs had positive cultures, with bacterial loads significantly decreasing after EVLP. Yeast loads increased when no anti-fungal treatment was given, but were reduced when prophylactic anti-fungal treatment was added to the circuit. Six lungs were ultimately transplanted into patients, all of whom survived to hospital discharge. There was 1 death at 11 months. CONCLUSIONS: Our study shows that EVLP with high-dose, empirical anti-microbial agents in the perfusate is associated with an effective reduction in the microbial burden of the donor lung, a benefit that has not previously been demonstrated.

Vascular anastomotic complications in lung transplantation: a single institution's experience.

OBJECTIVES: Lung transplant recipients were reviewed to compare our early and current experience of vascular complications. Since 1995, we have had a policy of early identification and intervention. METHODS: We undertook a retrospective review of all adult lung transplants performed at our centre. Patients with pulmonary vascular complications before and after 1995 were identified and reviewed to determine changes in management and outcome. RESULTS: We identified a total of 13 patients with either pulmonary artery or venous obstruction out of a total of 720 adult lung transplants (1.8%). There were 9 females and 4 males with an age range of 25-64 years. Complications were more common in patients with fibrotic lung disease and involved 15 vascular anastomoses, most commonly the pulmonary arterial anastomosis. Prior to 1995, 5 cases were identified, all postoperatively. In this group, the mean time for identification of the complication was 9.4 (range 4-14) days. Only 1 patient survived to discharge. After 1995, vascular complications were identified intraoperatively in 4 cases and corrected immediately. Four cases were identified postoperatively (at <1-17 days) by a computed tomography pulmonary angiogram. Three were treated surgically within 24 h of diagnosis (using cardiopulmonary bypass with cold preservation). One patient was managed conservatively. Among patients identified after 1995, 5 survived to discharge. CONCLUSIONS: Though rare, pulmonary vascular complications after lung transplantation carry high mortality. In our opinion, early identification and intervention improves outcome. Intraoperative assessment by pressure gradient measurement and transoesophageal echocardiography is recommended. Despite this, mortality remains high and prevention is better than cure.