Flores medical - multisonic - Inhalation mit Ultraschall

Transplantation medicine

PULMONARY HYPERTENSION IN TRANSPLANTATION MEDICINE

The transplantation of heart or lung may activate different pathomechanisms and thus lead to a postoperative increase in pulmonary vascular resistance. This increase in resistance plays a central role in primary transplant failure. However, this condition can, to a limited extent, be therapeutically influenced by changes in the ventilation regime (hyperoxia, hyperventilation). Vasodilatators require a lung-selective deposition also in transplantation medicine. Controlled studies have demonstrated that inhaled iloprost has a significant effect on pulmonary vascular resistance (PVR). One outcome of these studies was that approval was given for delivery of iloprost through an inhalation route in patients suffering from certain types of chronic pulmonary hypertension. Other publications describing the use of NO and epoprostenol after transplantation have found that inhaled epoprostenol produced a far clearer decrease in pulmonary resistance than intravenous nitroprusside while acting in a way similar to NO.

Terminal left-heart failure/Heart transplantation:
Heart transplant candidates with pulmonary hypertension associated with terminal left-heart failure were subsequently treated with inhaled NO and iloprost during preoperative evaluation of pulmonary vessel reactivity. Inhaled iloprost resulted in a much clearer reduction in pulmonary pressure and resistance compared with NO; distinct lung-selective haemodynamic effects were achieved in both cases and the systemic resistance remained uninfluenced. Comparable with findings for PAH, iloprost had a higher response rate than NO that induced paradoxical increases in pressure and resistance. Patients with terminal heart failure also seem to benefit from long-term inhaled iloprost therapy (bridging-to-transplant). Results obtained in the same patient cohort indicated that inhaled iloprost may have positive inotropic effects. These effects that were also described by preclinical studies might, in conjunction with the cytoprotective action of prostanoids and the influence on pulmonary haemodynamics, contribute to the patients becoming stable after orthotopic organ transplantation. Casuistries describe the successful use of inhaled iloprost in clinically critical situations following heart transplantations after other therapy options had failed. The authors consider iloprost the haemodynamically more efficient, easier-to-use, and safer alternative to NO.

Transplant conservation:
Adding iloprost to the transplant preservation medium can improve ischemic tolerance of transplants due to the cytoprotective and anti-inflammatory effects of the drug. A placebo-controlled study confirmed this effect in renal transplantations. Positive results have also been published for lung and islet cell transplantations. Intravenous administration of iloprost can have positive effects on therapy success after skin transplantation.

Liver transplantation:
Orthotopic liver transplantation can cause the pulmonary pressure to rise during the reperfusion phase. A randomized controlled study showed that the application of inhaled NO and/or iloprost resulted in a significant decrease in mean pulmonary artery pressure compared with the control group. Other than for NO, effects of inhaled iloprost were still detectable after several hours.