Lobar Lung Transplantation Research Articles

Current status and future of lung transplantation.

Lung transplantation has been performed successfully outside Japan since 1983 in patients with end-stage lung disease. More than 9,000 lung transplants have been reported in The Registry of the International Society for Heart and Lung Transplantation. In contrast, a transplant law became effective in Japan only recently, and four universities were designated as official lung transplant centers (Okayama, Osaka, Kyoto and Tohoku Universities). In October 1998, the first successful living-donor lobar lung transplantation was performed at Okayama University. Since then, seven lung transplants (four from living donors and three from cadaveric donors) have been successfully performed in Japan. Although lung transplantation offers acceptable prospects for 5-year survival, chronic rejection and donor shortage remain to be major problems. In an effort to address the donor shortage issue, living-donor lobar lung transplantations have been performed with satisfactory intermediate survival and functional results.

Effects of inhaled nitric oxide in a canine living-donor lobar lung transplant model.

In living-donor lobar lung transplantation, early severe graft dysfunction can occur if the size or amount of transplanted lung tissue is insufficient. The purpose of this study was to evaluate the effects of inhaled nitric oxide on early pulmonary function in a canine bilateral living-donor lobar lung transplant model. Sixteen pairs of mongrel dogs with a donor/recipient weight ratio less than 1.2 were used. The donor lung bloc was extirpated after heparinization. Right middle, lower and cardiac lobes were implanted as a right lung of the recipient and left lower lobe was implanted as a left lung without cardiopulmonary bypass. In Group 1 (n = 9), nitric oxide gas was administered continuously at a concentration of 40 parts per million prior to reperfusion of the right lung throughout the 6-hour assessment period after transplantation. In Group 2 (n = 7), nitrogen gas was administered in the same manner as nitric oxide, for control. At the end of assessment, the survival rate was 89% (8/9) in Group 1 and 57% (4/7) in Group 2. The arterial oxygen tension in Group 1 was significantly higher than that in Group 2. The pulmonary arterial pressure and pulmonary vascular resistance index were significantly lower in Group 1 than in Group 2. The aortic pressure and cardiac index did not differ significantly between the two groups. The wet-to-dry weight ratio and myeloperoxidase activity were significantly lower in Group 1 than in Group 2. These data suggested that inhaled nitric oxide improved early pulmonary function in living-donor lobar lung transplantation by vasodilatating the pulmonary vasculature and inhibiting neutrophil activation.

Referrals for lung transplantation in Japan. Unique indications and necessity of living-donor lobar lung transplantation.

The purpose of this study was to review all referrals to our lung transplant program and to find realistic options for accepted candidates in Japan. During the period from April 1992 to August 1999, 45 referrals were received. After screening, 22 of the referred patients were admitted for an extensive inpatient evaluation, and 15 of these were accepted as candidates for transplantation. The indication was primary pulmonary hypertension in 9, bronchiectasis in 2, lymphangioleiomyomatosis in 2, idiopathic pulmonary fibrosis in 1, and pneumoconiosis in the other 1. Two of those with primary pulmonary hypertension went to the USA and there received bilateral lung transplant. One with bronchiectasis received living-donor lobar lung transplantation in our center. These three recipients are alive and doing well during the follow-up period of 11 to 69 months. Among the 12 patients who have not received lung transplant, 5 patients have died while waiting. Indications for lung transplant are quite distinct in Japan, and primary pulmonary hypertension is the most frequent indication. Living-donor lobar lung transplantation is a realistic option for properly selected candidates.

Comparison of outcomes between living donor and cadaveric lung transplantation in children

Background. Long-term survival in lung transplant is limited by bronchiolitis obliterans (BOS). We compared outcomes in pediatric living donor bilateral lobar (LL) vs cadaveric lung transplant (CL).Methods. Children were studied who had LL or CL with at least 1 year follow-up. Data collected included acute rejection episodes, pulmonary function tests (PFT), BOS, and survival. Mean age was 13.36 ± 3.16 years in LL and 12.00 ± 4.19 years in CL patients (p = 0.37, ns).Results. There was no difference in rejection (p = 0.41, ns). CL had rejection earlier (2.48 ± 3.84 months) than LL (13.60 ± 10.74 months; p = 0.02). There was no difference in 12 month PFT. But at 24 months, LL had greater forced expiratory volume in 1 second (FEV1) (p = 0.001) and FEF25–75% (p = 0.01) than CL. BOS was found in 0/14 LL vs 9/11 (82%) CL after 1 year (p = 0.04). After 2 years, 0/8 LL and 6/7 (86%) CL had BOS (p < 0.05). LL had 85% survival vs 79% for CL at 12 months. At 24 months, LL survival was 77% vs 67% for CL.Conclusions. Pediatric LL had less BOS and better pulmonary function than CL. As BOS is a determinant of long-term outcome, we believe LL is the preferred lung transplant method for children.

Pulmonary volume increases with linear growth in pediatric living donor lobar lung transplant recipients: MS Woo, EF MacLaughlin, MV Horn, VA Starnes. Cardiothoracic Transplant Team. Childrens Hospital Los Angeles. University of Southern California School of Medicine. Los Angeles, California. USA

Pulmonary volume increases with linear growth in pediatric living donor lobar lung transplant recipients: MS Woo, EF MacLaughlin, MV Horn, VA Starnes. Cardiothoracic Transplant Team. Childrens Hospital Los Angeles. University of Southern California School of Medicine. Los Angeles, California. USA

Reduced-size lung transplantation from adult to neonatal swine.

Lung donor shortage is a critical factor limiting the expansion of pediatric lung transplantation programs. This report details the surgical technical feasibility of a training model of lobar lung transplantation as well as the perioperative monitoring to evaluate the appropriate pulmonary graft function. Ten hybrid Large-White pigs underwent left lower lobe lung allotransplantation; Donors weighed 15 to 20 kg and recipients 5 to 7 kg. The first five animals were used to learn the surgical anatomy and to establish the surgical technique and instrumentation's model (Group A). One hour after transplantation the right lung was excluded. Lung function and hemodynamic data were collected sequentially in the following five animals (Group B). The left inferior pulmonary lobe was found to be the most suitable allograft for transplantation. Usually, bronchial size discrepancy allowed telescoping of the airway anastomosis. Left atrial clamping was well tolerated during the pulmonary vein anastomoses. Preoperative antiaggregation and postoperatively heparinization achieved with ACT values over 200 seconds, prevented left atrial thrombosis. After right lung exclusion, hemodynamic changes consisted of a sustained increase in pulmonary vascular resistance and a reduction in cardiac output. Lung mechanics were also modified, with a gradual rise in airway resistance and a fall in compliance. The neonatal pig tolerates left lobar pulmonary transplantation satisfactorily. Although it is a useful and promising surgical learning model, questions remain regarding the applicability of this experience to clinical pediatric lung transplantation.

Ethical considerations in the treatment of cystic fibrosis.

Over the last several decades, rapid medical advancement in the treatment of persons with cystic fibrosis (CF) has brought with it a number of ethical concerns. The increasing life expectancy of persons with CF has made transitions in care increasingly common. This change in life expectancy along with advances in assisted reproductive technologies has focused attention on reproductive decision making in CF. Living lobar lung transplantation, although technically developed, remains ethically problematic. The understanding of ethical issues arising in the treatment of CF is crucial to providing optimal care.

Experimental bilateral lobar lung transplantation and its application in humans.

BACKGROUND: The critical lack of donor organs from people of small size or children has created great difficulties in transplantation for recipients who are of smaller size. Surgical techniques of...

Living donor lobar lung transplants and HLA matching: A preliminary report

Living donor lobar lung transplants and HLA matching: A preliminary report

Living-donor lobar lung transplantation experience: Intermediate results

Objective: Living-donor lobar lung transplantation offers an alternative for patients with a life expectancy of less than a few months. We report on our intermediate results with respect to recipient survival, complications, pulmonary function, and hemodynamic reserve. Methods: Thirty-eight living-donor lobar lung transplants were performed in 27 adult and 10 pediatric patients for cystic fibrosis (32), pulmonary hypertension (two), pulmonary fibrosis (one), viral bronchiolitis (one), bronchopulmonary dysplasia (one), and posttransplantation obliterative bronchiolitis (one). Seventy-six donors underwent donor lobectomies. Results: There were 14 deaths among the 37 patients, with an average follow-up of 14 months. Predominant cause of death was infection, consistent with the large percentage of patients with cystic fibrosis in our population. The overall incidence of rejection was 0.07 episodes/patient-month, representing 0.8 episodes/patient. Postoperative pulmonary function testing generally showed a steady improvement that plateaued by postoperative months 9 to 12. Fourteen patients who were followed up for at least 1 year underwent right heart catheterization; pressures and pulmonary vascular resistances were within normal ranges. Bronchiolitis obliterans was definitively diagnosed in three patients. Among the 76 donors, complications in the postoperative period included postpericardiotomy syndrome (three), atrial fibrillation (one), and surgical reexploration (three). Conclusions: We believe that these data support an expanded role for living-donor lobar lung transplantation. Our intermediate data are encouraging with respect to the functional outcome and survival of these critically ill patients, who would have died without this option. (J Thorac Cardiovasc Surg 1996;112:1284-91)

Anesthesia for living-related (lobar) lung transplantation

Anesthesia for living-related (lobar) lung transplantation

Combined lung and liver transplantation in patients with cystic fibrosis: A 4 1/2-year experience

Patients with cystic fibrosis who have end-stage respiratory failure and associated liver cirrhosis have been considered poor candidates for lung transplantation because of high morbidity and mortality resulting from hepatic insufficiency after the operation. Since April 1989, our policy has been to combine heart-lung or lung and liver transplantation in this group of patients. Between June 1990 and March 1995, among 25 patients accepted in the program for combined transplantation, nine died awaiting transplantation and 10 underwent one of the following procedures: heart-lung-liver transplantation ( n = 5), en bloc double lung–liver transplantation ( n = 1), sequential double lung–liver transplantation ( n = 3), and bilateral lobar lung transplantation from a split left lung and reduced liver transplantation ( n = 1). There were 5 male and 5 female patients. The ages of the recipients ranged from 10 to 24 years. Mean forced expiratory volume in 1 second was 29% and mean forced vital capacity was 35% of predicted values. All patients were infected with resistant Pseudomonas, three with Pseudomonas cepaceia, and two patients had Aspergillus species in addition. All patients had severe cirrhosis with portal hypertension. Four patients had a history of esophageal variceal bleeding and two had had previous portosystemic shunts. The operation was performed as a two-stage procedure, the intrathoracic operation being completed before the abdominal stage was begun. Cardiopulmonary bypass was used in all patients because of poor clinical condition. Immunosuppression consisted of azathioprine, cyclosporine, and prednisone, as for isolated lung transplantation. There were two perioperative deaths, one caused by primary liver failure and the second by early lung dysfunction. For the first 3 months after transplantation pulmonary infection was the most common cause of morbidity. Other complications included tracheal stenosis ( n = 1), bronchial stenosis ( n = 1), biliary stricture ( n = 2), and severe ascites ( n = 3). All were successfully treated. Obliterative bronchiolitis developed in three patients. This was stabilized with FK 506 in two patients; the other patient underwent retransplantation at 38 months but eventually died of bleeding. Actuarial survival was 70% at 1 year and remained unchanged at 3 years. Significant functional improvement was observed in all survivors. For patients who have chronic respiratory failure with advanced cirrhosis, lung transplantation combined with liver transplantation can be performed with a satisfactory outcome. (J THORAC CARDIOVASC SURG 1995;110:1415-23)

Living Related Donation in Lung Transplantation

Lung transplantation has become an established rescue therapy for patients with end-stage disease. The major problem, however, is the shortage of organ donors. Living related donation has been successful in kidney and liver transplantation and, recently, in lobar lung transplantation as well. The main ethical dilemma is whether we should risk a parent family member in order to save a child or relative. This dilemma can be taken to the extreme in a case in which pneumonectomy from a live donor can save a patient who is in need of single lung transplantation, a procedure that has not yet been performed, although technically feasible. We discuss the ethical aspects of such a procedure from the perspectives of the donor, the recipient, and the medical team.

Lobar lung transplantation as a treatment for congenital diaphragmatic hernia

The mortality rate for infants severely affected with congenital diaphragmatic hernia (CDH) remains high despite significant advances in surgical and neonatal intensive care including delayed repair and extracorporeal membrane oxygenation (ECMO). Because of the increasingly successful experience with single-lung transplantation in adults, this approach has been suggested as a potential treatment for CDH infants with unsalvageable pulmonary hypoplasia. The authors report on a newborn female infant who was the product of a pregnancy complicated by polyhydramnios. At birth, she was found to have a right-sided CDH and initially was treated with preoperative ECMO, followed by delayed surgical repair. Despite the CDH repair and apparent resolution of pulmonary hypertension, the infant's condition deteriorated gradually after decannulation, and escalating ventilator settings were required as well as neuromuscular paralysis and pressor support because of progressive hypoxemia and hypercarbia. A lung transplant was performed 8 days after decannulation, using the right lung obtained from a 6-week-old donor. The right middle lobe was excised because of the size discrepancy between the donor and recipient. After transplantation, the patient was found to have duodenal stenosis and gastroesophageal reflux, which required duodenoduodenostomy and fundoplication. The patient was discharged from the hospital 90 days posttransplantation, at 3 1 2 months of age. Currently she is 24 months old and doing well except for poor growth. This case shows the feasibility of single-lung transplantation for infants with CDH, and the potential use of ECMO as a temporary bridge to transplantation. Lobar lung transplantation allowed for less stringent size constraints for the donor lung.

Adult-to-neonate lung transplantation: Anatomic considerations

Babies born with severe pulmonary hypoplasia are unsai-vageable despite maximal therapy including extracorporeal membrane oxygenation (ECMO). Using ECMO as a bridge to transplantation, reduced-size lung grafts (pulmonary lobe or segment) could expand the pool of cadaver donors and may allow for HLA-matched living-related transplants. We tested this concept first in the piglet model and developed the technical maneuvers necessary to perform lobar and segmental lung transplants from adult pigs into neonatal piglets. Prior to clinical application, a systematic evaluation of anatomic considerations for reduced-size human lung transplantation was needed. A series of human adult and neonatal cadaver thoracic dissections were performed to determine the adult pulmonary lobe or segment with the proper size, orientation, and vascular and bronchial anatomy for use as a neonatal lung transplant. The adult right middle lobe (RML) is the best candidate for neonatal left lung replacement. The adult RML, once removed, can be rotated 180° around its superior-inferior axis and the vessels and bronchus align well in the left chest of the neonate. The RML may require further reduction to fit into the neonatal left chest. Selective arterial perfusion of the RML showed the anterior segment to be a near-perfect match for fit and anatomy. This technique may eventually permit living-related lung transplantation.

Living-related lobar lung transplantation in beagle puppies

Unilateral lung transplantation has provided effective short-term therapy in adults with end-stage lung disease. Rejection continues to be the most common cause of transplant failure. Living-related lung transplantation may decrease the recipient immune response. The purpose of this study is to test the technical and physiological feasibility of living-related lobar lung transplantation from adult beagles into beagle puppies in a chronic model. Twenty purebred adult beagle donors underwent left thoracotomy with harvest of the left lower lobe using cold perfusion of the pulmonary artery and cold immersion. Twenty recipient purebred beagle puppies from the same colony underwent left thoracotomy, left pneumonectomy, and implantation of the donor adult lobe. Anastomoses were performed in sequence: pulmonary vein to left atrium, bronchus, pulmonary artery. Postoperative immunosuppression was with Cyclosporine. Respiratory function of the implanted lobe was evaluated by pulmonary angiography and during balloon occlusion of the right pulmonary artery with arterial blood gases 1 month after transplantation. Ten recipient puppies died of rejection (4), infection (3), or bronchial dehiscence (3) prior to angiography. Seventeen pulmonary angiograms in 10 surviving animals showed normal left pulmonary arterial blood flow (2), diminished left pulmonary arterial flow (5), and occluded left pulmonary artery (3). In two recipients balloon occlusion of the right pulmonary artery was performed and respiratory function was maintained solely by the transplanted lobe for 2 days in one recipient and for 30 minutes at 1 month and 2 months postimplant in a second recipient. Living-related lung transplantation of adult beagle lobes into pneumonectomized beagle puppies is technically feasible. High mortality rates in a chronic model are related to infection and rejection. In survivors the transplanted lobe appears physiologically capable of providing full respiratory support.

Reduced-size lung transplantation in neonatal swine: Technique and short-term physiological response

Lung transplantation is now a clinical reality in adults but is limited by the scarcity of appropriate donors. The donor shortage is even more acute for neonatal and pediatric patients. Reduced-size lung grafts would expand the pool of appropriate cadaveric donors and allow HLA-matched living related lobar or segmental lung transplants. To evaluate this experimentally, we developed a model of pulmonary lobar transplantation in neonatal pigs and studied the acute hemodynamic response after transplanting the left lower lobe from a more mature donor to a neonatal recipient. Technical considerations included using the recipient atrial appendage for the pulmonary venous anastomosis. Nine pairs of pigs underwent left lateral thoracotomy. The recipient left atrial and pulmonary arterial pressures, cardiac output, and pulmonary vascular resistance were measured before pneumonectomy and after left lower lobe transplantation. Although the left atrial and pulmonary arterial pressures remained unchanged after transplantation, there was a 15% increase in pulmonary vascular resistance and a 23% reduction in cardiac output. Neither change was statistically significant. The distribution of blood flow through the left and right pulmonary arteries was unchanged after transplantation. We conclude that lobar transplantation is technically feasible in immature animals and that the pulmonary venous anas tomosis to the left atrial appendage facilitates the procedure. This model may prove useful in studying lung transplantation in immature recipients and expedite implementation of reduced-size lung transplantation in neonatal and pediatric patients.