Pulmonary blood flow is inhomogeneously reduced after Euro Collins-preservation and lung transplantation

Bronchoscopic surfactant administration preserves gas exchange and pulmonary compliance after single lung transplantation in dogs

BACKGROUND

Surfactant abnormalities have been implicated in reperfusion injury and respiratory failure in lung transplantation.

METHODS

We investigated the efficacy of bronchoscopic administration of a bovine natural lung surfactant extract (Alveofact) to improve gas exchange and lung mechanics after heterologous left lung transplantation in foxhounds (+4 degrees C ischemia for 24 hours, conservation with Euro-Collins solution). Animals received either no surfactant therapy (untreated controls, n = 6) or 50 mg/kg body weight (prior to explantation, only graft) and 200 mg/kg body weight Alveofact (immediately after reperfusion, both lungs, n = 6). After lung transplantation, separate but synchronized ventilation of each lung was performed in a volume-controlled, pressure-limited mode for 12 hours, with the animals prone. Small catheters were inserted into the pulmonary veins of both the graft and the recipient's native lung for separate blood gas analysis. In the control group, marked protein leakage, influx of neutrophils into the alveolar space, and pulmonary edema formation (extravascular lung water; wet/dry ratio) were encountered in the transplanted lung but only to a very minor extent in the recipient's native lung.

RESULTS

Lung compliance values and arterial oxygenation progressively deteriorated in the transplanted but not in the native lungs. Pulmonary hemodynamics did not change significantly. Surfactant administration did not significantly influence the development of reperfusion edema, protein leakage, and neutrophil influx into the grafts. However, surfactant restored the surface activity and the gas exchange (PaO2/FIO2 of 201.2 +/- 20.2 mm Hg vs 119.8 +/- 21.7 mm Hg in controls; P <.05) in the transplanted lungs, and compliance was markedly improved in the surfactant-treated animals (18.8 +/- 1.8 mL/mbar vs 11.5 +/- 1.6 mL/mbar in the controls; P <.05).

CONCLUSION

Bronchoscopic surfactant administration does not prevent leukocyte influx or vascular leakage but does protect against respiratory failure and improves lung mechanics in single lung transplantation in dogs.

Trasplante renal pediatrico con injertos de donantes infantiles de corta edad (. 6 anos). complicaciones y evolucion funcional

GOALS

To evaluate functional results and complications in a group of pediatric patients who received kidney transplants from donors aged 6 years or less.

MATERIAL & METHODS

Thirty-four consecutive renal transplants were reviewed. Of 34 patients, 19 (55.8%) received kidneys from donors aged below 3 years (Group A) and 15 (44.2%) from donors aged 3-6 years (Group B). Long-term functional patient and graft survival results along with complications were compared in both groups.

RESULTS

Seven patients in group A (36.7%) had vascular complications, in comparison to 3 in group B (20%, p<0.05). Kidneys preserved in Eurocollins (EC) solution had more vascular complications (35.3%) in comparison to University of Wisconsin (UW) solution kidneys (23.5%, p<0.05). Ten-year graft survival rate in group A was significantly lower in comparison to group B (35.5% vs 58.6%, p<0.05). In relation to preservation solution type used, 10-year graft survival rate was also significantly better in UW group (26.8% vs 63%, p<0.001).

CONCLUSIONS

The exclusion of donors younger than 3 years and the utilization of optimal preservation solutions produces a decrease in figures of vascular complications and a significant improvement in graft survival rates.

Induction of endotoxin tolerance improves lung function after warm ischemia in dogs

In shock models, induction of endotoxin tolerance (ET) is known to have a protective effect. The present study was designed to explore if ET is effective in protecting lungs from reperfusion injury. Twelve foxhounds were used as experimental animals. After a left thoracotomy, the left hilum was clamped for 3 h, followed by 8 h of reperfusion. In the treatment group (ET, n = 6), dogs were pretreated with incremental daily endotoxin doses of up to 60 microg/kg on day 6. The ischemia and reperfusion experiment was carried out on day 9. Control group animals (n = 6) were not subjected to endotoxin. After 8 h of observation, functional parameters of the reperfused lung of the ET and the control group were statistically different (P < 0.05) with respect to Po(2) [ET vs. control: 172.7 +/- 12.9 vs. 66.1 +/- 7.2 (SE) mmHg], compliance (16.0 +/- 1.2 vs. 8.3 +/- 1.0 ml/0.1 kPa), and the wet-to-dry ratio (9.4 +/- 0.8 vs. 16.7 +/- 1.2). After 3 h of warm ischemia and 8 h of reperfusion, pulmonary function and lung water content improved in the endotoxin-tolerant group.