Acute and chronic pleural complications in lung transplantation

[Heart and heart-lung transplants thorax complications: major radiologic forms]

Bipulmonary and cardiopulmonary transplantations are among the most difficult to perform, with a 10-year survival rate estimated at 33%. This low rate can be attributed to thoracic complications that can be classified into three distinct groups: 1) early complications, occurring in the first 30 days after transplantation (hemothorax, diaphragmatic paralysis, reperfusion edema, hydric overloading, acute rejection); 2) late complications that occur beyond the first month (bronchiolitis obliterans syndrome, bronchic stenosis, sirolimus-induced lung disorders, initial disease recurrence); and 3) infections classed separately because of their high morbidity and mortality (thoracic wall abscess, bacterial and viral pneumonia, CMV, pneumocystosis, Aspergillus necrotizing bronchitis). Imaging is essential in screening and diagnosing these complications as part of the clinician's monitoring throughout the rest of the transplant recipient's life. In diagnosis, combined with clinical and biological data, imaging has its place in delaying the onset of these diseases.

Noninfectious Pulmonary Complications After Lung Transplantation

This article reviews several important noninfectious pulmonary complications that threaten survival, pulmonary function, and quality of life after lung transplantation. Topics reviewed include primary graft dysfunction (PGD), native lung hyperinflation, anastomotic complications, phrenic nerve injury, pleural complications, lung cancer, pulmonary toxicity associated with immunosuppressive medications, and exercise limitation.

Pleural Space Problems After Living Lobar Transplantation

BACKGROUND

We reviewed our experience with adult living lobar lung transplant (LL) recipients to assess whether size and shape mismatch of the donor organ to the recipient pre-disposes to the development of pleural space problems (PSP).

METHODS

Eighty-seven LL were performed on 84 adult recipients from 1993 through 2003. Seventy-six patients had cystic fibrosis. Patient records were examined for PSP, defined as air leak or bronchopleural fistula for more than 7 days; pneumothorax, loculated pleural effusions, or empyema in 68 patients for which complete data were available.

RESULTS

There were 24 PSP identified for an overall incidence of 35%. The most common PSP was air leak/bronchopleural fistula, accounting for 38% of PSP. The second most common PSP was loculated pleural effusion (21% of PSP). Empyema was uncommon (2 patients, 3% of total patients) in our series of patients despite the large population of cystic fibrosis patients. In 4 of these patients, computed tomography-guided drainage was used for loculated effusions after chest tube removal. Three LL patients underwent surgery for persistent air leak and required muscle flap repair. One of these required subsequent omental transfer. Two LL patients required decortication for empyema. Many patients with PSP could be managed without further surgical intervention (14/24 patients). Donor-recipient height mismatch was not significantly different between PSP and non-PSP patients (p = 0.53).

CONCLUSIONS

The incidence of PSP in LL recipients is similar to that reported in the literature on cadaveric transplant recipients. The relatively small lobe in the potentially contaminated chest cavity of cystic fibrosis recipients does not significantly pre-dispose to development of empyema despite immunosuppression. Many PSP can be managed non-operatively, although early aggressive intervention for large air leaks and judicious chest tube management are essential for a good outcome.

Pre-transplant panel reactive antibody in lung transplant recipients is associated with significantly worse post-transplant survival in a multicenter study

BACKGROUND

The presence of antibodies to human leukocyte antigens (HLA) prior to transplantation has been linked to worse post-transplant outcomes in many solid organ transplants. The effect of these antibodies is less clear in lung transplant recipients, although previous studies have suggested an increased incidence of allograft dysfunction.

METHODS

A retrospective study of all first lung transplant recipients from the University of Toronto (November 1983-July 2001, n = 380) and Duke University (April 1992-June 2000, n = 276) was performed. Demographic data, survival information, and level of last pre-transplant panel reactive antibody (PRA) were collected. PRA level was measured by the complement-dependent cell cytotoxicity assay at both centers. Survival analysis was performed using the Kaplan-Meier method, and groups were compared with the Wilcoxon rank sum test.

RESULTS

Of 656 lung transplant recipients, 101 (15.4%) had a PRA greater than 0, 37 (5.6%) had a PRA greater than 10%, and 20 (3.0%) had a PRA greater than 25%. Patients with a PRA greater than 25% had decreased median survival than did the rest of the patients (1.5 vs 5.2 years) and at 1 month (70% vs 90%), 1 year (65% vs 76%), and 5 years (31% vs 50%), respectively (p = 0.006, Wilcoxon's rank sum test) test).

CONCLUSION

Significant elevation of PRA prior to lung transplantation is associated with worse survival, especially in the early post-transplant period. This may be due to a direct effect of anti-HLA antibodies on the allograft. The effectiveness of treatments such as plasmapheresis and intravenous immunoglobulin prior to transplantation needs to be evaluated.

Short-term deployment of self-expanding metallic stents facilitates healing of bronchial dehiscence

Bronchial dehiscence after lung transplantation is difficult to treat and associated with high mortality. We describe our experience using self-expanding metallic stents to treat post-lung transplant bronchial dehiscence. From January 1995 to June 2004, 189 single and 118 double lung transplants were performed in our institution, totaling 425 at-risk bronchial anastomoses. Seven (1.6%) incidents of life-threatening bronchial dehiscence were treated with self-expanding metallic stents. The interval between transplant and diagnosis of dehiscence was 29.1 +/- 18.5 days. All patients presented with respiratory distress, and three required mechanical ventilation. Self-expanding metallic stent placement resulted in complete bronchial healing. All three patients with respiratory failure requiring mechanical ventilation were successfully weaned after stent placement. In two later cases, the stents were electively removed after adequate healing of the dehiscence. Complications included stent migration (one patient) and in-stent stenosis (three patients). Two of these patients required repeat stent insertion after removal, due to bronchomalacia. In patients with life-threatening bronchial dehiscence, self-expanding metallic stents offer prospects for a successful outcome. Self-expanding metallic stents are known to be associated with significant granulation tissue formation, and this property provides a platform for healing of dehiscence and, in time, peribronchial soft tissue grows in to cover the defect, allowing stent removal.