Perfil do doador de pulmão disponibilizado no estado de São Paulo, Brasil, em 2006

Ultrasound Scanning in Lung Procurement. Protocol for Decision-Making With the Purpose of Increasing Transplant Eligible Lungs

BACKGROUND

The main obstacle to obtaining lungs for transplantation is the shortage of donors. Once potential donors have been offered to transplant programs, the acceptance rate is highly variable, ranging from 5% to 20%. Minimizing donor leakage by converting potential lung donors into real donors is one of the key elements to improve results, and it is essential to have tools that facilitate decision-making in this scenario. The selection and rejection of transplantation-eligible lungs are usually made with chest x-rays; however, lung ultrasound scanning has shown better sensitivity and specificity for diagnosing pulmonary pathologies. Lung ultrasound scanning allows us to identify the reversible causes of low PaO2/fraction of inspired oxygen (FIO2) ratio, thus enabling the establishment of specific interventions, which, if proved successful, could turn lungs into transplant-eligible lungs. The available literature on its use in managing brain death donors and lung procurement is extremely scarce.

METHODS

A simple protocol aimed at identifying and treating the main reversible causes of low PaO2/FIO2 ratio to aid in decision-making is presented in this paper.

CONCLUSION

Lung ultrasound is a powerful, useful, and cheap technique available at the donor's bedside. It is conspicuously underused, despite being potentially helpful in decision-making by minimizing the discarding of donors, thus probably increasing the number of lungs sui for transplantation.

Lung transplantation and organ allocation in Brazil: necessity or utility

The philosophy of organ allocation is the result of two seemingly irreconcilable principles: utilitarianism and distributive justice. The process of organ donation and transplantation in Brazil reveals large inequalities between regions and units of the Federation, from the harvesting of organs to their implantation. In this context, lung transplantation is performed in only a few centers in the country and is still a treatment with limited long-term results. The allocation of the few organs harvested for the few procedures performed is defined mainly by chronology, a criterion that is not linked to necessity, which is a criterion of distributive justice, and neither to utility, a criterion of utilitarianism. This article reviews the organ allocation philosophy focusing on the case of lung transplantations in Brazil.

Burkholderia cepacia, cystic fibrosis and outcomes following lung transplantation: experiences from a single center in Brazil

OBJECTIVES

To evaluate the impact of Burkholderia cepacia complex colonization in cystic fibrosis patients undergoing lung transplantation.

METHODS

We prospectively analyzed clinical data and respiratory tract samples (sputum and bronchoalveolar lavage) collected from suppurative lung disease patients between January 2008 and November 2013. We also subtyped different Burkholderia cepacia complex genotypes via DNA sequencing using primers against the recA gene in samples collected between January 2012 and November 2013.

RESULTS

From 2008 to 2013, 34 lung transplants were performed on cystic fibrosis patients at our center. Burkholderia cepacia complex was detected in 13 of the 34 (38.2%) patients. Seven of the 13 (53%) strains were subjected to genotype analysis, from which three strains of B. metallica and four strains of B. cenocepacia were identified. The mortality rate was 1/13 (7.6%), and this death was not related to B. cepacia infection.

CONCLUSION

The results of our study suggest that colonization by B. cepacia complex and even B. cenocepacia in patients with cystic fibrosis should not be considered an absolute contraindication to lung transplantation in Brazilian centers.

Effect of the systemic administration of methylprednisolone on the lungs of brain-dead donor rats undergoing pulmonary transplantation

OBJECTIVE

Most lung transplants are obtained from brain-dead donors. The physiopathology of brain death involves hemodynamics, the sympathetic nervous system, and inflammatory mechanisms. Administering methylprednisolone 60 min after inducing brain death in rats has been shown to modulate pulmonary inflammatory activity. Our objective was to evaluate the effects of methylprednisolone on transplanted rat lungs from donors treated 60 min after brain death.

METHODS

Twelve Wistar rats were anesthetized, and brain death was induced. They were randomly divided into two groups (n=6), namely a control group, which was administered saline solution, and a methylprednisolone group, which received the drug 60 min after the induction of brain death. All of the animals were observed and ventilated for 2 h prior to being submitted to lung transplantation. We evaluated the hemodynamic and blood gas parameters, histological score, lung tissue levels of thiobarbituric acid-reactive substances, level of superoxide dismutase, level of tumor necrosis factor-alpha, and level of interleukin-1 beta.

RESULTS

After transplantation, a significant reduction in the levels of tumor necrosis factor-alpha and IL-1β was observed in the group that received methylprednisolone (p=0.0084 and p=0.0155, respectively). There were no significant differences in tumor necrosis factor-alpha and superoxide dismutase levels between the control and methylprednisolone groups (p=0.2644 and p=0.7461, respectively). There were no significant differences in the blood gas parameters, hemodynamics, and histological alterations between the groups.

CONCLUSION

The administration of methylprednisolone after brain death in donor rats reduces inflammatory activity in transplanted lungs but has no influence on parameters related to oxidative stress.

Effects of methylprednisolone on inflammatory activity and oxidative stress in the lungs of brain-dead rats

OBJECTIVE:

To evaluate the effects that early and late systemic administration of methylprednisolone have on lungs in a rat model of brain death.

METHODS:

Twenty-four male Wistar rats were anesthetized and randomly divided into four groups (n = 6 per group): sham-operated (sham); brain death only (BD); brain death plus methylprednisolone (30 mg/kg i.v.) after 5 min (MP5); and brain death plus methylprednisolone (30 mg/kg i.v.) after 60 min (MP60). In the BD, MP5, and MP60 group rats, we induced brain death by inflating a balloon catheter in the extradural space. All of the animals were observed and ventilated for 120 min. We determined hemodynamic and arterial blood gas variables; wet/dry weight ratio; histological score; levels of thiobarbituric acid reactive substances (TBARS); superoxide dismutase (SOD) activity; and catalase activity. In BAL fluid, we determined differential white cell counts, total protein, and lactate dehydrogenase levels. Myeloperoxidase activity, lipid peroxidation, and TNF-α levels were assessed in lung tissue.

RESULTS:

No significant differences were found among the groups in terms of hemodynamics, arterial blood gases, wet/dry weight ratio, BAL fluid analysis, or histological score-nor in terms of SOD, myeloperoxidase, and catalase activity. The levels of TBARS were significantly higher in the MP5 and MP60 groups than in the sham and BD groups (p < 0.001). The levels of TNF-α were significantly lower in the MP5 and MP60 groups than in the BD group (p < 0.001).

CONCLUSIONS:

In this model of brain death, the early and late administration of methylprednisolone had similar effects on inflammatory activity and lipid peroxidation in lung tissue.

Histologic and functional evaluation of lungs reconditioned by ex vivo lung perfusion

BACKGROUND

Only about 15% of donor lungs are considered suitable for transplantation (LTx). Ex vivo lung perfusion (EVLP) has been developed as a method to reassess and repair damaged lungs. We report our experience with EVLP in non-acceptable donor lungs and evaluate its ability to recondition these lungs.

METHODS

We studied lungs from 16 brain-dead donors rejected for LTx. After harvesting, the lungs were stored at 4°C for 10 hours and subjected to normothermic EVLP with Steen Solution (Vitrolife, Göteborg, Sweden) for 60 minutes. For functional evaluation, the following variables were assessed: partial pressure of arterial oxygen (Pao(2)), pulmonary vascular resistance (PVR), and lung compliance (LC). For histologic assessment, lung biopsy was done before harvest and after EVLP. Tissue samples were examined under light microscopy. To detect and quantify apoptosis, terminal deoxynucleotide transferase-mediated deoxy uridine triphosphate nick-end labeling assay was used.

RESULTS

Thirteen lung donors were refused for having impaired lung function. The mean Pao(2) obtained in the organ donor at the referring hospital was 193.7 mm Hg and rose to 489 mm Hg after EVLP. During EVLP, the mean PVR was 652.5 dynes/sec/cm(5) and the mean LC was 48 ml/cm H(2)O. There was no significant difference between the mean Lung Injury Score before harvest and after EVLP. There was a trend toward a reduction in the median number of apoptotic cells after EVLP.

CONCLUSIONS

EVLP improved lung function (oxygenation capacity) of organs considered unsuitable for transplantation. Lung tissue structure did not deteriorate even after 1 hour of normothermic perfusion.

Prognostic factors in lung transplantation: the Santa Casa de Porto Alegre experience

BACKGROUND

Lung transplantation (LT) has been established as a current therapy for selected patients with end-stage lung disease. Different prognostic factors have been reported by transplant centers. The objective of this study is to report our recent results with LT and to search for prognostic factors.

METHODS

We performed a retrospective analysis of 130 patients who underwent LT at our institution from January 2004 to July 2009. Donor, recipient, intraoperative, and postoperative variables were collected.

RESULTS

The mean age was 53.14 years (ranging from 8 to 72 years) and 80 (61.5%) were male. The main causes of end-stage respiratory disease were pulmonary fibrosis 53 (40.7%) and chronic obstructive pulmonary disease 52 (40%). The actuarial 1-year survival was 67.7%. Variables correlated with survival were age (P=0.004), distance in the 6-min walk test (P=0.007), coronary heart disease (P=0.001), cardiopulmonary bypass (P=0.02), intraoperative transfusion of red blood cells (P=0.016), increasing central venous pressure at 24th postoperative hour (P=0.001), increasing pulmonary capillary wedge pressure at 24th postoperative hour (P=0.01); length of intubation (P<0.01), reintubation (P=0.001), length of intensive care unit stay (P<0.001), abdominal complication (P=0.003), acute renal failure requiring dialysis (P<0.001), native lung hyperinflation (P=0.02), and acute rejection in the first month (P=0.03). In multivariate analysis, only dialysis (P=0.004, hazards ratio [HR] 2.68), length of intubation (P=0.004, HR 1.002 for each hour), and reintubation (P=0.003, HR 2.88) proved to be independent predictors.

CONCLUSION

Analysis of variables in our cohort highlighted dialysis, longer mechanical ventilation requirement, and reintubation as independent prognostic factors in LT.

Recommendations for the use of extended criteria donors in lung transplantation

Selection criteria for lung donation were based on initial experiences with lung transplantation without further studies to improve them, thereby guaranteeing the best use of donated organs. A definition of an extended criteria donor is therefore required to obtain more lungs to meet the demands of patients awaiting transplantation. Studies have been reviewed for the impact on survival and morbidity of age ranges, oxygen fraction, cause of death, smoking habits, x-ray findings, infection, hepatitis serology and non-heart-beating status, seeking to support physicians to make decisions regarding the use of marginal organs.