Short-term outcome in living donors for lung transplantation: the role of preoperative computer tomographic evaluations of fissures and vascular anatomy

Native upper lobe-sparing living-donor lobar lung transplantation maximizes respiratory function of the donor graft

BACKGROUND

We have developed a novel method for native upper lobe-sparing living-donor lobar lung transplantation (LDLLT) to overcome a small-for-size graft in standard LDLLT with acceptable results. We hypothesized that grafts implanted with this procedure might work more efficiently than those in standard lobe transplantation.

METHODS

Bilateral LDLLT was performed in 31 patients with a functional graft matching of less than 60% at our institution between August 2008 and December 2015. Of these, 22 patients were available for evaluation of pulmonary function more than 1 year later: 15 undergoing standard LDLLT with less than 60% functional matching and 7 undergoing native upper lobe-sparing LDLLT.

RESULTS

Overall survival at 2 years was 87.5% in the lobe-sparing LDLLT patients and 79.0% in the standard LDLLT patients (p = 0.401). The median forced vital capacity size-matching levels were 50.7% ± 1.6% in the standard LDLLT and 45.2% ± 2.3% in the sparing LDLLT group (p = 0.074). The 1-year and 2-year post-operative volume ratios of inspiration to expiration were significantly different between the 2 groups, at 1.76 and 1.45 after standard LDLLT (p = 0.019) vs 2.41 and 2.23 after lobe-sparing LDLLT (p = 0.015).

CONCLUSIONS

The grafts in lobe-sparing LDLLT functioned more effectively than those in standard LDLLT. This advantage was associated with the improvement of pulmonary functions.

Impact of donor chest radiography on clinical outcome after lung transplantation

Background

Organ donation guidelines recommend a “clear” conventional bedside chest radiograph before lung transplantation despite only moderate accuracy for cardiopulmonary abnormalities.

Purpose

To evaluate the influence of donor image interpretation on lung transplantation outcome in recipients by following early and late complications, one-year survival, and to correlate imaging findings and blood gas analysis with lung transplantation outcome in recipients.

Material and Methods

In 35 lung donors from a single institution clinical reports and study reviews of imaging findings of the mandatory bedside chest radiographs and blood gas analyses were compared with clinical outcome in 38 recipients. Hospitalization time, peri- and postoperative complications, early complications (primary graft dysfunction, infection), 30-day and one-year survival, and forced expiratory volume in 1 s percentage of predicted normal value (FEV1%) at one-year follow-up were analyzed.

Results

Findings in clinical reports and study reviews differed substantially, e.g. regarding reported decompensation, edema, infection, and atelectasis. No correlation was shown between imaging findings in clinical report or study review and blood gas analyses in the lung donors compared to postoperative outcome in recipients.

Conclusion

The interpretation of the mandatory chest radiograph in its present form does not influence one-year outcome in lung transplantation. Larger imaging studies or a change in clinical routine including computed tomography may provide evidence for future guidelines.

Three-dimensional image in lung transplantation

Three-dimensional computed tomography (3D-CT) technologies have been developed and, recently, high-speed and high-quality 3D-CT technologies have been introduced to the field of thoracic surgery. The purpose of this manuscript is to demonstrate the clinical application of 3D-CT technologies in lung transplantation. In Japan, because of the severe donor shortage, living-donor lobar lung transplantation (LDLLT) is essential, in addition to cadaveric lung transplantation. In LDLLT, size matching is a grave issue, since ideal size matching between donor and recipient is usually difficult because of the limited population of potential donor. Size matching using pulmonary function test results has been widely used as a gold standard, but anatomical size matching using 3D-CT volumetry data has also been utilized in LDLLT. In donor lobectomy, 3D-CT images provided a variety of information regarding anatomical variation of pulmonary vessels and bronchial trees preoperatively. These images ensure surgical quality and safety, and they also affect surgical procedures for the recipient. 3D-CT images are also utilized in various aspects of postoperative care, such as detection of chronic lung allograft dysfunction and clarification of its subtypes. Furthermore, preoperative 3D-CT simulation is useful in developing and performing a special surgical procedure, such as right-to-left inverted LDLLT. In conclusion, following the introduction of 3D-CT to the field of thoracic surgery, various 3D-CT images and their application to preoperative simulations have been introduced in lung transplantation. In the near future, this technique will become more prevalent, and frequent use by thoracic surgeons will be seen worldwide in daily practice.

Living-related lung transplantation

Living-donor lobar lung transplantation (LDLLT) was developed to deal with the severe shortage of brain dead door for patients who would not survive the long waiting period. In standard LDLLT, right and left lower lobes removed from two healthy donors are implanted into a recipient after right and left pneumonectomies using cardiopulmonary bypass (CPB). The number of LDLLT has decreased in the USA due to the recent change in allocation system for cadaveric donor lungs. For the past several years, most of the reports on LDLLT have been from Japan, where the average waiting time for a cadaveric lung is exceeding 800 days. LDLLT has been performed both for adult and pediatric patients suffering from various end-stage lung diseases including restrictive, obstructive, vascular and infectious lung diseases. Since only two lobes are implanted, size matching is a very important issue. Functional size matching by measuring donor pulmonary function and anatomical size matching by three-dimensional computed tomography (3D-CT) volumetry are very useful. For oversize graft, we have employed several techniques, including single lobe transplantation, delayed chest closure, downsizing the graft, and middle lobe transplantation. In cases of undersize mismatch, native upper lobe sparing transplant or right-left inverted transplant was performed. The 5-, 10- and 15-year survivals were 80.8%, 72.6% and 61.7%, respectively. There was no difference in survival between standard LDLLT and non-standard LDLLT such as single, sparing and inverted transplant. All donors have been discharged without any restrictions. LDLLT is a viable option for very ill patients who would not survive a long waiting time for cadaveric lungs. We have successfully developed various surgical techniques to overcome size mismatching with favorable outcome.

Outcomes of various transplant procedures (single, sparing, inverted) in living-donor lobar lung transplantation

OBJECTIVES

In standard living-donor lobar lung transplantation (LDLLT), the right and left lower lobes from 2 healthy donors are implanted. Because of the difficulty encountered in finding 2 donors with ideal size matching, various transplant procedures have been developed in our institution. The purpose of this retrospective study was to compare outcomes of nonstandard LDLLT with standard LDLLT.

METHODS

Between June 2008 and January 2016, we performed 65 LDLLTs for critically ill patients. Functional size matching was performed by estimating graft forced vital capacity based on the donor's measured forced vital capacity and the number of pulmonary segments implanted. For anatomical size matching, 3-dimensional computed tomography volumetry was performed. In cases of oversize mismatch, single-lobe transplant or downsizing transplant was performed. In cases of undersize mismatch, native upper lobe sparing transplant or right-left inverted transplant was performed. In right-left inverted transplants, the donor's right lower lobe was inverted and implanted into the recipient's left chest cavity.

RESULTS

Twenty-nine patients (44.6%) received nonstandard LDLLT, including 12 single-lobe transplants, 7 native upper lobe sparing transplants, 6 right-left inverted transplants, 2 sparing + inverted transplants, and 2 others. Thirty-six patients (57.4%) received standard LDLLT. Three- and five-year survival rates were similar between the 2 groups (89.1% and 76.6% after nonstandard LDLLT vs 78.0% and 71.1% after standard LDLLT, P = .712).

CONCLUSIONS

Various transplant procedures such as single, sparing and inverted transplants are valuable options when 2 donors with ideal size matching are not available for LDLLT.

Update on three-dimensional image reconstruction for preoperative simulation in thoracic surgery

BACKGROUND

Three-dimensional computed tomography (3D-CT) technologies have been developed and refined over time. Recently, high-speed and high-quality 3D-CT technologies have also been introduced to the field of thoracic surgery. The purpose of this manuscript is to demonstrate several examples of these 3D-CT technologies in various scenarios in thoracic surgery.

METHODS

A newly-developed high-speed and high-quality 3D image analysis software system was used in Kyoto University Hospital. Simulation and/or navigation were performed using this 3D-CT technology in various thoracic surgeries.

RESULTS

Preoperative 3D-CT simulation was performed in most patients undergoing video-assisted thoracoscopic surgery (VATS). Anatomical variation was frequently detected preoperatively, which was useful in performing VATS procedures when using only a monitor for vision. In sublobar resection, 3D-CT simulation was more helpful. In small lung lesions, which were supposedly neither visible nor palpable, preoperative marking of the lesions was performed using 3D-CT simulation, and wedge resection or segmentectomy was successfully performed with confidence. This technique also enabled virtual-reality endobronchial ultrasonography (EBUS), which made the procedure more safe and reliable. Furthermore, in living-donor lobar lung transplantation (LDLLT), surgical procedures for donor lobectomy were simulated preoperatively by 3D-CT angiography, which also affected surgical procedures for recipient surgery. New surgical techniques such as right and left inverted LDLLT were also established using 3D models created with this technique.

CONCLUSIONS

After the introduction of 3D-CT technology to the field of thoracic surgery, preoperative simulation has been developed for various thoracic procedures. In the near future, this technique will become more common in thoracic surgery, and frequent use by thoracic surgeons will be seen in worldwide daily practice.

Expanding the lung donor pool: advancements and emerging pathways

PURPOSE OF REVIEW

The number of patients listed for lung transplantation largely exceeds the number of available transplantable organs because of a shortage of organ donors and a low utilization rate of lungs from those donors who are available. In recent years, novel strategies have been developed to increase the donor lung pool: improved donor management, the use of lungs from donations after cardiac death (DCD), the use of lobar lung living-donors (LLLD) and the use of ex-vivo lung perfusion (EVLP) to assess and repair injured donor lungs.

RECENT FINDINGS

An adapted donor management strategy could expand the donor pool up to 20%. DCD lung transplant is an increasing part of the donor pool expansion. Outcomes after controlled DCD seem to be similar to donation after brain death. LLLD transplantation has excellent results for small and critically ill patients. EVLP treatment allows for a significant increase in the rate of suitable lungs and represents an optimal platform for lung reconditioning and specific lung therapies.

SUMMARY

A significant increase in the number of available lungs for transplantation is expected in the future because of the wider use of lungs from controlled or uncontrolled DCD and LLLD lungs, and with organ-specific EVLP treatment strategies.

Unilateral chronic lung allograft dysfunction is a characteristic of bilateral living-donor lobar lung transplantation

OBJECTIVES

Living-donor lobar lung transplantation (LDLLT) has been established as a life-saving procedure for critically ill patients who cannot wait for cadaveric lung transplantation. Chronic lung allograft dysfunction (CLAD) is the main cause of late morbidity and mortality in lung transplantation. Studies on CLAD in cadaveric lung transplantation have been extensively reported, but few reports have been reported concerning CLAD after LDLLT. The aim of this study was to determine the prevalence, characteristics and prognosis of CLAD after LDLLT.

METHODS

Among 38 patients who survived more than 3 months after LDLLT at Kyoto University Hospital between June 2008 and December 2013, 8 patients (21%) were diagnosed with CLAD. The mean follow-up period after LDLLT was 33 months. Clinical course, pulmonary function and radiological findings were reviewed retrospectively in all the 38 patients as of May 2014.

RESULTS

Six patients were female and 2 were male. The median age at LDLLT was 31 years, and the median interval between LDLLT and the initial diagnosis of CLAD was 23 months. Among 8 patients who developed CLAD, 2 patients underwent right single LDLLT and 6 patients underwent bilateral LDLLT. The former 2 patients survived 44 and 47 months after the treatment. Five out of 6 patients with bilateral LDLLT developed unilateral CLAD at the time of initial diagnosis according to ventilation scintigraphy. In 3 of these 5 patients, the progression of CLAD was halted by treatment, and the median follow-up period of 33 months after treatment. In the remaining 2 of 5 patients, CLAD progressed to the contralateral lung metachronously; 1 patient survived without oxygen supplement, but the other patient required reperformance of LDLLT 3 years after the first one. One patient with bilateral CLAD at the time of detection died of disease progression 4 years after LDLLT.

CONCLUSIONS

Despite a relatively short observation time, CLAD developed in approximately one-fifth of the patients who survived more than 3 months after LDLLT. In bilateral LDLLT, CLAD developed unilaterally in most cases, which might be beneficial in the long term because the unaffected contralateral lung may function as a reservoir.

Living donor lobar lung transplantation: a longstanding concept being revisited with the same old NEMESIS

INTRODUCTION

Living donor lobar lung transplantation (LDLLT) has been successfully used in select patient populations.

MATERIALS AND METHODS

A 29-year-old male, who underwent bilateral LDLLT 12 years earlier with allografts donated by father and paternal uncle, developed bronchiolitis obliterans syndrome at distinctly different rates.

CONCLUSION

LDLLT can be done successfully with unique management issues.