Current Management And Selection Of Potential Lung Donors For Lung Transplantation

This manuscript discusses recent and evolving advances in the field of lung transplantation. Lung transplantation is still limited by the shortage of suitable donor organs. This results in long waiting times for listed patients with a substantial risk (10-15%) of dying before transplantation. All efforts to increase donor awareness through legislation, public campaigns, and training of transplant coordinators and medical ICU staff should be encouraged. Only a minority of cadaveric donors meets the preset ideal lung donor criteria, leaving many transplantable lungs untouched.This manuscript further reviews the current management and selection of potential lung donors for lung transplantation in the field of lung transplantation. The below are some of the current changes and proposals in lung transplantation;l)As an advancement in technology, surgical technique, and immunosuppression, the past few decades have seen a shift from using a very conservative set of donor criteria to extended, or marginal, donor criteria. Although the results varied, outcomes of transplantation using extended-criteria donor lungs have generally been acceptable.2)A successful living donor lobar lung transplantation has been offered to a small number of patients with advanced lung disease.3)Novel methods of donor management, lung preservation, and ex-vivo therapeutics have focused on minimizing the incidence and effect of primary graft dysfunction (PGD) after transplantation.4)Moreover the exact traditional recommendations for donor management were to ventilate the lungs with a tidal volume of 10-15 mL/kg; however A 2010 trial by Mascia and colleagues investigated on ventilation of brain-dead donors for 6hours with 6-8 mL/kg tidal volumes and higher positive end-expiratory pressure as well as the effect of recruitment manoeuvres after any disconnection from the ventilator.5)Some guidelines recommend initiating hormone resuscitation in the setting of hemodynamic instability, other groups advocate initiation when left ventricular ejection fraction is below 45%, and yet others recommend broad empirical use in all donors.7)A range of prediction tools to determine death within 60 min or 120 min in potential DCD candidates have been assessed. However, broad application of these methods has not shown consistent results between time predicted and actual time of death. More research must be encouraged to identify which variables can better predict accurate time of d e a th.8)Lung inflation and the administration of oxygen are known to protect donor lungs through three mechanisms:preservation of pulmonary surfactant, preservation of epithelial fluid transport, and maintenance of aerobic metabolism. Therefore, the optimum lung inflation pressure is unknown.9)Its been noted that perfusion volume of 60 mL/kg is used by most centers, after a study by Haverich and colleagues which revealed that a high volume and high flow rate improved postoperative lung function and achieved better lung cooling than a lower volume at a lower flow rate. Although 150 mL/kg has also been used in some centers, it has not been found to be better than 60 mL/kg with regard to post-transplantation outcomes.10)The use of mesenchymal stem cells to reduce extravascular lung water is also in experimental stages, but could have a profound effect on minimizing neurogenic pulmonary edema in the setting of neurological death. Not every lung transplantation center has the capabilities and expertise for EVLP; however, a recent clinical trial reported successful remote EVLP to assess and improve function, transportation, and transplantation of donor lungs, demonstrating the concept of an organ repair Center.