Airway complications after lung transplantation: a review of 151 anastomoses

Risk Factors, Incidence, and Outcomes Associated With Clinically Significant Airway Ischemia

Airway complications following lung transplantation remain an important cause of morbidity and mortality. We aimed to identify the incidence, risk factors and outcomes associated with clinically significant airway ischemia (CSAI) in our center. We reviewed 217 lung transplants (386 airway anastomoses) performed at our institution between February 2016 and December 2020. Airway images were graded using the 2018 ISHLT grading guidelines modified slightly for retrospective analysis. Airways were considered to have CSAI if they developed ischemia severity >B2, stenosis >50%, and/or any degree of dehiscence within 6-months of transplant. Regression analyses were used to evaluate outcomes and risk factors for CSAI. Eighty-two patients (37.8%) met criteria for CSAI. Of these, twenty-six (32%) developed stenosis and/or dehiscence, and 17 (21%) required interventions. Patients with CSAI had lower one-year (80.5% vs. 91.9%, p = 0.05) and three-year (67.1% vs. 77.8%, p = 0.08) survival than patients without CSAI. Factors associated with CSAI included younger recipient age, recipient diabetes, single running suture technique, performance of the left anastomosis first, lower venous oxygen saturation within 48-h, and takeback for major bleeding. Our single-center analysis suggests that airway ischemia remains a major obstacle in contemporary lung transplantation. Improving the local healing milieu of the airway anastomosis could potentially mitigate this risk.

Lung Transplantation under a Janus Kinase Inhibitor in Three Patients with SAVI Syndrome

Stimulator of interferon genes (STING)-associated vasculopathy with onset in infancy (SAVI) is a very rare autoinflammatory disease related to STING1 mutation. SAVI is mainly characterized by fever attacks and skin and respiratory manifestations such as interstitial lung disease or alveolar hemorrhage. Respiratory involvement occurs in 80% of cases and might progress to severe lung fibrosis and require lung transplantation (LT). Three patients with SAVI who underwent LT have been reported to date. Two of the three patients died months or years after LT due to multiple organ failure or sepsis. However, the diagnosis of SAVI was made after LT, thus preventing the use of targeted therapy, such as the Janus kinase 1 and 2 inhibitor (JAK1/2i) ruxolitinib, which might be beneficial for the respiratory status of these patients. We aimed to report our experience in managing three patients who were followed in three large lung transplantation centers in France and who benefited from ruxolitinib before undergoing LT. We describe posttransplant complications that occurred as well as outcomes.

Risk factors and prognosis of airway complications in lung transplant recipients: A systematic review and meta-analysis

BACKGROUND

Airway complications (AC) are one of leading causes of morbidity and mortality after lung transplant (LTx), but their predictors and outcomes remain controversial. This study aimed to identify potential risk factors and prognosis of AC.

METHODS

A systematic review was performed by searching PubMed, Embase, and Cochrane Library. All observational studies reporting outcome and potential factors of AC after LTx were included. The incidence, mortality, and estimated effect of each factor for AC were pooled by using the fixed-effects model or random-effects model.

RESULTS

Thirty-eight eligible studies with 52,116 patients undergoing LTx were included for meta-analysis. The pooled incidence of AC was 12.4% (95% confidence interval [CI] 9.5-15.8) and the mean time of occurrence was 95.6 days. AC-related mortality rates at 30-days, 90-days, 6 months, 1 year, and 5 years were 6.7%, 17.9%, 18.2%, 23.6%, and 66.0%, respectively. Airway dehiscence was the most severe type with a high mortality at 30 days (60.9%, 95% CI 20.6-95.2). We found that AC was associated with a higher risk of mortality in LTx recipients (hazard ratio [HR] 1.71, 95% CI 1.04-2.81). Eleven significant predictors for AC were also identified, including male donor, male recipient, diagnosis of COPD, hospitalization, early rejection, postoperative infection, extracorporeal membrane oxygenation, mechanical ventilation, telescopic anastomosis, and bilateral and right-sided LTx.

CONCLUSION

AC was significantly associated with higher mortality after LTx, especially for dehiscence. Targeted prophylaxis for modifiable factors and enhanced early bronchoscopy surveillance after LTx may improve the disease burden of AC.

Airway Complications after Lung Transplantation-A Contemporary Series of 400 Bronchial Anastomoses from a Single Center

(1) Objective: To determine whether recent advances in lung transplantation (LT) have reduced the incidence and changed the risk factors for airway complications (AC). (2) Methods: Retrospective analysis of patients receiving a lung transplant between January 2007 and January 2019. An AC was defined as a bronchoscopic abnormality in the airway, either requiring or not requiring an endoscopic or surgical intervention. Both univariable and multivariable analyses were performed to identify risk factors for AC. (3) Results: 285 lung transplants (170 single and 115 bilateral lung transplants) were analysed, comprising 400 anastomoses at risk. A total of 50 anastomoses resulted in AC (12%). There were 14 anastomotic and 11 non-anastomotic stenoses, 4 dehiscences, and 3 malacias. Independent predictors for AC were: gender male (OR: 4.18; p = 0.002), cardiac comorbidities (OR: 2.74; p = 0.009), prolonged postoperative mechanical ventilation (OR: 2.5; p = 0.02), P_aO₂/F_iO₂ < 300 mmHg at 24 h post-LT (OR: 2.48; p = 0.01), graft infection (OR: 2.16; p = 0.05), and post-LT isolation of Aspergillus spp. (OR: 2.63; p = 0.03). (4) Conclusions: In spite of advances in lung transplantation practice, the risk factors, incidence, and lethality of AC after LT remains unchanged. Graft dysfunction, an infected environment, and the need of prolonged mechanical ventilation remain an Achilles heel for AC.

Alterations in Pulmonary Physiology with Lung Transplantation

Lung transplant is a treatment option for patients with end-stage lung diseases; however, survival outcomes continue to be inferior when compared to other solid organs. We review the several anatomic and physiologic changes that result from lung transplantation surgery, and their role in the pathophysiology of common complications encountered by lung recipients. The loss of bronchial circulation into the allograft after transplant surgery results in ischemia-related changes in the bronchial artery territory of the allograft. We discuss the role of bronchopulmonary anastomosis in blood circulation in the allograft posttransplant. We review commonly encountered complications related to loss of bronchial circulation such as allograft airway ischemia, necrosis, anastomotic dehiscence, mucociliary dysfunction, and bronchial stenosis. Loss of dual circulation to the lung also increases the risk of pulmonary infarction with acute pulmonary embolism. The loss of lymphatic drainage during transplant surgery also impairs the management of allograft interstitial fluid, resulting in pulmonary edema and early pleural effusion. We discuss the role of lymphatic drainage in primary graft dysfunction. Besides, we review the association of late posttransplant pleural effusion with complications such as acute rejection. We then review the impact of loss of afferent and efferent innervation from the allograft on control of breathing, as well as lung protective reflexes. We conclude with discussion about pulmonary function testing, allograft monitoring with spirometry, and classification of chronic lung allograft dysfunction phenotypes based on total lung capacity measurements. We also review factors limiting physical exercise capacity after lung transplantation, especially impairment of muscle metabolism. © 2023 American Physiological Society. Compr Physiol 13:4269-4293, 2023.

Incidence, risk factors, and clinical characteristics of airway complications after lung transplantation

Airway complications may occur after lung transplantation and are associated with considerable morbidity and mortality. We investigated the incidence, risk factors, and clinical characteristics of these complications. We retrospectively reviewed the medical records of 137 patients who underwent lung transplantation between 2008 and 2021. The median follow-up period was 20 months. Of the 137 patients, 30 (21.9%) had postoperative airway complications, of which 2 had two different types of airway complications. The most common airway complication was bronchial stenosis, affecting 23 patients (16.8%). Multivariable Cox analysis revealed that a recipient's body mass index ≥ 25 kg/m² (hazard ratio [HR], 2.663; p = 0.013) was a significant independent risk factor for airway complications, as was postoperative treatment with extracorporeal membrane oxygenation (ECMO; HR, 3.340; p = 0.034). Of the 30 patients who had airway complications, 21 (70.0%) were treated with bronchoscopic intervention. Survival rates did not differ significantly between patients with and without airway complications. Thus, our study revealed that one fifth of patients who underwent lung transplantation experienced airway complications during the follow-up period. Obesity and receiving postoperative ECMO are risk factors for airway complications, and close monitoring is warranted in such cases.

Incidence and risk factors of anastomotic complications after lung transplantation

Background:

Anastomotic complications are common after lung transplantation (1.4–33% of cases) and still associated with a high morbi-mortality.

Methods:

The current study is a monocenter retrospective analysis of symptomatic anastomotic complications (SAC) occurring after lung transplantation between 2010 and 2016, using the macroscopic, diameter, and suture (M-D-S) classification from consensus of French experts in bronchoscopy. The objectives were to determine incidence from surgery, risk factors, and impact of survival of SAC. We defined SAC as M-D-S abnormalities (stenosis ⩾ 50% or dehiscence) requiring bronchoscopic or surgical interventions.

Results:

A total of 121 patients were included. SAC occurred in 26.5% of patients (n = 32), divided in symptomatic stenosis for 23.7% (n = 29), and symptomatic dehiscence in 2.5% (n = 3). In multivariate analysis, donor bacterial lung infection [HR 2.08 (1.04–4.17), p = 0.04] and age above 50 years [HR 3.26 (1.04–10.26), p = 0.04] were associated with SAC occurrence. Cystic fibrosis etiology was associated with better survival on Kaplan–Meier curve (p < 0.001). SAC [HR 2.15 (1.07–4.32), p = 0.03] was independently associated with worst survival. The 29 symptomatic patients because of stenosis required endoscopic procedure, of whom 16 patients needed bronchial stent placement. Four patients underwent surgery: three patients because of dehiscence and one because of severe bilateral stenosis (re-transplantation).

Discussion:

SAC occurred in 26.5% of patients. Donor lung infection was the only alterable identified factors. The increase rate of SAC in older patients above 50 years of age encourages in regular endoscopic monitoring.

Veno-venous extracorporeal membrane oxygenation in the management of refractory bilateral bronchial dehiscence after lung transplant: a case report

Background

Bronchial dehiscence is a life-threatening complication after lung transplant. If it is not treated by placement of stent or reanastomosis, the chance of survival will depend on the availability of a new graft. However, retransplant is not a practical management option in Japan, where waiting time for lung transplant is extensive. We described a case of refractory bilateral bronchial dehiscence managed by veno-venous extracorporeal oxygenation membrane (VV ECMO) while allowing the dehiscence to heal.

Case presentation

A 25-year-old man with idiopathic pulmonary arterial hypertension underwent a bilateral lung transplant. The patient developed bilateral bronchial dehiscence. Open reanastomosis was not successful, and air leakage recurred under low positive pressure ventilation. VV ECMO was established to maintain oxygenation with spontaneous breathing until both dehiscence were closed by adhesions.

Conclusion

In a patient with refractory bilateral bronchial dehiscence, VV ECMO may provide bronchial rest and serve as a bridge therapy to recovery.

POST-OPERATIVE BRONCHIAL COMPLICATIONS FOLLOWING LUNG TRANSPLANTATION RELATED TO ANASTOMOSIS SUTURE

BACKGROUND

Post-operative bronchial anastomotic complications are not uncommon in lung transplant (LTx) recipients. We investigated two surgical techniques (continuous and interrupted sutures) during bronchial anastomosis, comparing survival and post-operative bronchial complications.

METHODS

We retrospectively analyzed 421 patients who were transplanted in our center (February-2012 to March-2018). Patients were divided according to bronchial anastomotic technique, continuous or interrupted. Demographics and clinical parameters were compared for significance (p<0.05). Comparison of post-operative morbidity included bronchial complications, Veno-Venous extracorporeal membrane oxygenation support and intervention requirements. Survival was assessed using Kaplan-Meier curve and log-rank tests (p<0.05).

RESULTS

Of the 421 patients, 290 underwent bronchial anastomoses with continuous suture; 44 patients had post-operative bronchial complications (15.2%). Contrarily, 131 patients underwent the interrupted suture technique; 9 patients had post-operative bronchial complications (6.9%). Demographics and clinical parameters included age, gender, ethnicity, etiology, lung allocation score, body mass index, donor age, LTx type, cardiopulmonary bypass usage, surgical approaches, and median length of stay. Post-operative complications (continuous vs. interrupted) were bronchial complications (p=0.017), Veno-venous extracorporeal membrane oxygenation support (p=0.41), Veno-arterial extracorporeal membrane oxygenation support (p=0.38), and complications requiring dilatation with stent placement (p=0.09). Kaplan-Meier curve showed better survival in the interrupted group (p=0.0002).

CONCLUSIONS

Our study demonstrated the comparable post-operative results between the continuous and interrupted technique.

Utility and Safety of Airway Stenting in Distal Airways Stenosis After Lung Transplant

BACKGROUND

Airway complications after lung transplantation are a difficult to treat clinical entity. A subset of these patients develop progressive distal airway stenosis (DAS) and a total loss of lobar airways. Stents may be placed to prevent continued obstruction. However, there is little data to suggest stent placement provides durable airway patency or a reduction in the need for further interventions.

METHODS

A retrospective cohort study was conducted using patients with DAS who underwent a variety of interventions. Demographic information and complications were described using nonparametric methods. Lung function at 1 year and bronchoscopies per month were compared between stented and nonstented patients using a Mann-Whitney test. For patients treated with stenting, bronchoscopies per month were compared before and after stenting using a Wilcoxon signed-rank test. Airway patency was compared between stented and nonstented patients using the Fischer exact test.

RESULTS

Eleven airways were identified as DAS phenotype, 5 of which were treated with stents. Within the stented airways, a trend toward an increase in bronchoscopies per month was seen after stent placement. Comparing the stented versus nonstented patients, there was no improvement in lung function, no reduction in bronchoscopies per month, and no difference in airway patency for stented patients.

CONCLUSION

Patients with DAS phenotypes that were treated with endobronchial stenting did not require less airway intervention or have greater final airway patency compared with the nonstented airways. Among the stented patients, the need for airway manipulation did not decrease after stent placement.

Hybrid reconstruction of bronchial dehiscence following lung transplant

Surgical repair of right-sided bronchial dehiscence post lung transplant is challenging. We report a hybrid reconstruction of the bronchus using an aortic homograft patch with stenting as a novel technique of management of ischemic airway injury following lung transplantation.

Efficacy and safety of airway stenting to treat anastomotic complications after lung transplant: a cohort study

Background

Airway complications affect roughly 15–20% of lung transplant patients. Airway stents are an attractive therapeutic option; however, no experimental or controlled observational data exists to draw firm conclusions regarding airway stent efficacy and safety in this population.

Methods

We performed a retrospective cohort study of patients who underwent airway stent placement for post-transplant anastomotic airway complications. The primary outcomes were improvements in FEV1 and reduction in bronchoscopies post-stent.

Results

We identified 36 patients who underwent airway stenting between October 2012 and October 2017. A total of 47 airways underwent stent placement. Improvement in FEV1 after stent placement was only observed in patients who ultimately were able to undergo stent removal. Patients who expired prior to stent removal had no immediate FEV1 improvement after stent placement. Among subjects who underwent stent removal, there was a statistically significant reduction in number of bronchoscopies per month after stent removal compared to pre-stent placement. Male gender was the only predictor of FEV1 improvement after stent placement while male gender and dehiscence prior to stent placement predicted increased number of bronchoscopies after stent placement. Mucous plugging and granulation tissue formation were the most common stent related complications.

Conclusions

Only select patients benefit from stent placement for airways stenosis after lung transplant. Complications related to stent placement are common. Patients with airway complications treated with airway stents undergo a high volume of repeat procedures.

Impact of Cold Ischemia Time on Frequency of Airway Complications Among Lung Transplant Recipients

BACKGROUND

The cold ischemia time (CIT) is a period of time between harvesting an organ for transplant and its reperfusion just after implantation. CIT may have an impact on frequency of complications after lung transplant that can be treated by means of bronchoscopic intervention. The aim of the study was to investigate the correlation between CIT and frequency of bronchoscopic intervention.

METHODS

The retrospective study consists of 91 patients: 22 single lung recipients (24%) and 69 double lung recipients (76%) who underwent lung transplant from March 2012 to June 2019. All statistical analyses were performed in SPSS 25.0 and R 3.5.3. The P levels less than .05 were deemed statistically significant.

RESULTS

The average CIT in single lung transplant was 5.91 hours, and in double lung transplant it was 8.61 hours. For the 4- to 8-hour CIT the percentages were 80.95% for single lung recipients and 46.38% for double lung recipients. For CIT longer than 8 hours, the following percentages were observed: 9.53% in single lung transplant and 53.62% in double lung transplant. Each subsequent hour of CIT exponentially increases the risk of intervention 1505 times (50.05%).

CONCLUSIONS

Prolonged CIT seems to be a risk factor for airway complication, especially in the double lung recipient group.

Imaging Evaluation of Airway Complications After Lung Transplant

Airway complications (ACs) after lung transplant remain a challenge and include bronchial dehiscence, bronchial stenosis, tracheobronchomalacia, infections, and bronchial fistulas. The spectrum of complications may coexist along a continuum and can be classified as early (<1 month after transplant) or late (>1 month), and anastomotic or nonanastomotic. Bronchiolitis obliterans is the most common form of chronic lung allograft rejection. Airway compromise is seen in rare instances of lung torsion, and imaging may provide helpful diagnostic clues. Computed tomography (CT) and bronchoscopy play major roles in the diagnosis and treatment of ACs after lung transplant. Chest CT with advanced postprocessing techniques is a valuable tool in evaluating for airways complications, for initial bronchoscopic treatment planning and subsequent posttreatment assessment. Various bronchoscopic treatment options may be explored to maintain airway patency. The goal of this article is to review imaging findings of ACs after lung transplantation, with emphasis on chest CT and bronchoscopic correlation.

What have we learned in interventional pulmonology in the past decade?

Background/aim

The increasing number of lung diseases and particularly pulmonary malignancies has intensified the need for diverse interventions in the field of interventional pulmonology. In recent years we have seen many new developments and expanding applications in the field of interventional pulmonology. This has resulted in an increased number and variety of performed procedures and differing approaches. The purpose of the present study is to provide information on patient characteristics, range of interventions, complication rates, and the evolving approach of an experienced center for interventional pulmonology.

Materials and methods

We retrospectively examined the records of 1307 patients who underwent a total of 2029 interventional procedures in our interventional pulmonology department between January 2008 and December 2017.

Results

About half of the interventional procedures (47.2%) were performed on patients with airway stenosis due to malignant disease. Among patients with benign airway stenosis, the most frequent reason for intervention was postintubation tracheal stenosis. The number of patients who developed complications was 81 (6.2%), and the most common complication was hemorrhage (n = 31, 2.99%); 94.9% (n = 1240) of interventional procedures were performed under general anesthesia, without complications or deaths associated with anesthesia. Only one death (0.076%) occurred in the perioperative period. A total of 18 patients (1.38%) died in the 30-day perioperative and postoperative period. None of the patients with benign airway stenosis died.

Conclusion

Interventional bronchoscopy is an invasive but considerably safe and efficient procedure for selected cases and effective treatment modality for airway obstructions, massive hemoptysis, and foreign body aspiration. Interventional pulmonology is a field of pulmonary medicine that needs effort to progress and provide an opportunity to witness relevant developments, and increase the number of competent physicians and centers.

Preoperative Corticosteroid Use and Early Postoperative Bronchial Anastomotic Complications after Lung Transplantation

Background

Airway anastomotic complications are a leading cause of mortality after lung transplantation. Among the factors that cause airway complications, preoperative steroid use has been considered to be related with postoperative airway healing. We analyzed the influence of preoperative steroid use on postoperative airway complications.

Methods

The medical records of 66 double-lung transplant recipients from January 2014 to December 2015 were reviewed. Forty patients were prescribed steroids preoperatively. The daily steroid dose was standardized using the patient’s body mass index (BMI). Patients who received preoperative steroids were sub-divided into high-dose (HD) and low-dose (LD) groups (cut-off value, 1.6 mg/BMI/day).

Results

Thirteen patients suffered from airway complications postoperatively (bronchopulmonary fistula, 9; bronchial stenosis, 4). There was a tendency for early development of airway complications in the steroid use group compared to the non-steroid use group, but it was not significant (percentage free from airway complications in year 1: non-steroid group, 90.9% vs. steroid group, 79.2%; p=0.43). The percentage of patients in the LD and HD groups who were free from airway complications in year 1 was not significantly different (84.0% vs. 77.8%, p=0.39).

Conclusion

The airway complication rate did not vary significantly according to steroid use. Additionally, in patients who received preoperative steroids, the dose did not affect the rate of development of airway complications.

ISHLT Consensus Statement on adult and pediatric airway complications after lung transplantation: Definitions, grading system, and therapeutics

Airway complications remain a major cause of morbidity and mortality after cardiothoracic transplantation. The reported incidence of airway ischemic complications varies widely, contributed to by the lack of a universally accepted grading system and standardized definitions. Furthermore, the majority of the existing classification systems fail to integrate the wide range of possible bronchial complications that may develop after lung transplant. Hence, a Working Group was created by the International Society for Heart and Lung Transplantation with the aim of elaborating a universal definition of adult and pediatric airway complications and grading system. One such area of focus is to understand the problem in the context of a more standardized consensus of classifying airway ischemia. This consensus definition will have major clinical, therapeutics, and research implications.

Imaging of Lung Transplantation

Lung transplantation has become a viable treatment option for end-stage lung disease. Common indications for lung transplantation are chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis, cystic fibrosis, alpha-1 antitrypsin deficiency, and pulmonary arterial hypertension. Either single or bilateral lung transplantation can be performed, but bilateral lung recipients appear to have a better median survival than single lung recipients. Complications after lung transplantation are common and may have nonspecific clinical and radiologic manifestations. The time point at which these complications occur relative to the date of transplant is crucial in formulating a differential diagnosis and recognizing them accurately. Significant advances in imaging techniques and recognition of air trapping in exhalation images and other patterns /distribution of parenchymal abnormalities have led to routine use of HRCT for diagnostic evaluation in patients manifesting respiratory decline in the lung transplant recipient.

Transplant Pulmonary Interventions: Translating Lung Transplant Interventions to Nontransplant Patients

Roughly 10% of lung transplant recipients experience airway complications. Although the incidence has decreased dramatically since the first lung transplants were performed in the 1960s, airway complications have continued to adversely affect outcomes. Bronchoscopic interventions such as balloon dilation, airway stenting, and endobronchial electrocautery play an important role in ameliorating the morbidity and mortality associated with these complications. This review describes the array of bronchoscopic interventions used to treat airway complications after lung transplant and how these techniques can be used in nontransplant settings as well.

Bronchial complications after lung transplantation are associated with primary lung graft dysfunction and surgical technique

BACKGROUND

After lung transplantation, bronchial complications are one of the major concerns for surgeons and physicians. In the era of evolving immunosuppressive regimens and surgical approaches, we have reassessed risk factors for bronchial complications after lung transplantation.

METHODS

We undertook a retrospective study of all consecutive lung transplantations performed at a single center from 2004 to 2014. We monitored the incidence of symptomatic bronchial complications. Demographic data of donors and recipients were also studied. Our objective was to evaluate the impact of 3 subsequent immunosuppressive regimens (including the use of induction therapy), and of a technical modification of bronchial anastomosis on the incidence of airway complications.

RESULTS

We performed 270 consecutive lung transplantations during the study period. On multivariate analysis, bronchial complications were not directly associated with the different immunosuppressive regimens. In subgroup analysis, when comparing different immunosuppressive regimens, primary graft dysfunction within 72 hours (odds ratio [OR] = 2.55; p = 0.08), lung infection within the first month (OR = 2.96; p = 0.039), diabetes before transplantation (OR = 2.66; p = 0.11) and chronic obstructive pulmonary disease (OR = 2.20; p = 0.04) appeared as major risk factors (c-index = 0.77 on multivariate analysis). The use of a modified bronchial suture technique was associated with fewer bronchial complications (OR = 0.47; p = 0.059) (c-index = 0.71 on multivariate analysis).

CONCLUSIONS

The mode of immunosuppression had no influence on airway complications. We were able to reproduce the beneficial effect of a modified suture technique.

Iatrogenic-related transplant injuries: the role of the interventional radiologist

As advances in surgical techniques and postoperative care continue to improve outcomes, the use of solid organ transplants as a treatment for end-stage organ disease is increasing. With the growing population of transplant patients, there is an increasing need for radiologic diagnosis and minimally invasive procedures for the management of posttransplant complications. Typical complications may be vascular or nonvascular. Vascular complications include arterial stenosis, graft thrombosis, and development of fistulae. Common nonvascular complications consist of leaks, abscess formation, and stricture development. The use of interventional radiology in the management of these problems has led to better graft survival and lower patient morbidity and mortality. An understanding of surgical techniques, postoperative anatomy, radiologic findings, and management options for complications is critical for proficient management of complex transplant cases. This article reviews these factors for kidney, liver, pancreas, islet cell, lung, and small bowel transplants.

Airway complications after lung transplantation

Airway complications after lung transplantation present a formidable challenge to the lung transplant team, ranging from mere unusual images to fatal events. The exact incidence of complications is wide-ranging depending on the type of event, and there is still evolution of a universal characterization of the airway findings. Management is also wide-ranging. Simple observation or simple balloon bronchoplasty is sufficient in many cases, but vigilance following more severe necrosis is required for late development of both anastomotic and nonanastomotic airway strictures. Furthermore, the impact of coexisting infection, rejection, and medical disease associated with high-level immunosuppression further complicates care.

Coupled cellular therapy and magnetic targeting for airway regeneration

Airway diseases including COPD (chronic obstructive pulmonary disease), cystic fibrosis and lung cancer are leading causes of worldwide morbidity and mortality, with annual healthcare costs of billions of pounds. True regeneration of damaged airways offers the possibility of restoring lung function and protecting against airway transformation. Recently, advances in tissue engineering have allowed the development of cadaveric and biosynthetic airway grafts. Although these have produced encouraging results, the ability to achieve long-term functional airway regeneration remains a major challenge. To promote regeneration, exogenously delivered stem and progenitor cells are being trialled as cellular therapies. Unfortunately, current evidence suggests that only small numbers of exogenously delivered stem cells engraft within lungs, thereby limiting their utility for airway repair. In other organ systems, magnetic targeting has shown promise for improving long-term robust cell engraftment. This technique involves in vitro cell expansion, magnetic actuation and magnetically guided cell engraftment to sites of tissue damage. In the present paper, we discuss the utility of coupling stem cell-mediated cellular therapy with magnetic targeting for improving airway regeneration.

Imaging in lung transplants: Checklist for the radiologist

Post lung transplant complications can have overlapping clinical and imaging features, and hence, the time point at which they occur is a key distinguisher. Complications of lung transplantation may occur along a continuum in the immediate or longer postoperative period, including surgical and mechanical problems due to size mismatch and vascular as well as airway anastomotic complication, injuries from ischemia and reperfusion, acute and chronic rejection, pulmonary infections, and post-transplantation lymphoproliferative disorder. Life expectancy after lung transplantation has been limited primarily by chronic rejection and infection. Multiple detector computed tomography (MDCT) is critical for evaluation and early diagnosis of complications to enable selection of effective therapy and decrease morbidity and mortality among lung transplant recipients.

A comparative analysis of bronchial stricture after lung transplantation in recipients with and without early acute rejection

BACKGROUND

Risk factors and outcomes of bronchial stricture after lung transplantation are not well defined. An association between acute rejection and development of stricture has been suggested in small case series. We evaluated this relationship using a large national registry.

METHODS

All lung transplantations between April 1994 and December 2008 per the United Network for Organ Sharing (UNOS) database were analyzed. Generalized linear models were used to determine the association between early rejection and development of stricture after adjusting for potential confounders. The association of stricture with postoperative lung function and overall survival was also evaluated.

RESULTS

Nine thousand three hundred thirty-five patients were included for analysis. The incidence of stricture was 11.5% (1,077/9,335), with no significant change in incidence during the study period (P=0.13). Early rejection was associated with a significantly greater incidence of stricture (adjusted odds ratio [AOR], 1.40; 95% confidence interval [CI], 1.22-1.61; p<0.0001). Male sex, restrictive lung disease, and pretransplantation requirement for hospitalization were also associated with stricture. Those who experienced stricture had a lower postoperative peak percent predicted forced expiratory volume at 1 second (FEV1) (median 74% versus 86% for bilateral transplants only; p<0.0001), shorter unadjusted survival (median 6.09 versus 6.82 years; p<0.001) and increased risk of death after adjusting for potential confounders (adjusted hazard ratio 1.13; 95% CI, 1.03-1.23; p=0.007).

CONCLUSIONS

Early rejection is associated with an increased incidence of stricture. Recipients with stricture demonstrate worse postoperative lung function and survival. Prospective studies may be warranted to further assess causality and the potential for coordinated rejection and stricture surveillance strategies to improve postoperative outcomes.

Secondary carina Y-stent placement for post-lung-transplant bronchial stenosis

BACKGROUND

Post-lung-transplant bronchial stenosis (TBS) may cause significant morbidity and mortality. Although often transiently relieved by balloon bronchoplasty, stents may be required for long-term airway patency. We report a series of lung transplant patients in whom a silicone Y-stent was placed at the secondary carina for long-standing relief of post-transplant-airway stenosis.

METHODS

Six lung transplant patients received 10 silicone Y-stents in the secondary carina over the past 18 months for post-transplant-bronchial stenosis. All patients failed other interventional therapeutic procedures including balloon bronchoplasty and/or conventional stenting before secondary carina Y-stent placement. Patient data include 12 months' follow-up after Y-stent insertion. The number of procedures and the interval between procedures was examined before and after secondary carina silicone Y-stent placement.

RESULTS

There was a significantly prolonged therapeutic effect accomplished in these patients after secondary carina Y-stent placement with the exception of 1 patient. When stents were tolerated by the patient, the mean number of procedures before secondary carina Y-stent insertion was 15.6, but only 4.8 after Y-stent insertion. The number of days between procedures was 24.5 days before the Y-stent insertion and 85.8 days after the Y-stent insertion. There were no complications in any patient during secondary carina Y-stent insertion.

CONCLUSIONS

Secondary carina silicone Y-stent placement in TBS decreased the number of therapeutic procedures and provided longer-lasting results in most posttransplant patients who required multiple prior procedures for TBS.

Significance of and risk factors for the development of central airway stenosis after lung transplantation

Central airways stenosis (CAS) after lung transplant is a poorly understood complication. Objectives of this study were to determine if CAS was associated with chronic rejection or worse survival after transplant as well as to identify factors associated with CAS in a large cohort of lung transplant recipients. Lung transplant recipients transplanted at a single center were retrospectively reviewed for the development of CAS requiring airway dilation. A total of 467 subjects met inclusion criteria with 60 (13%) of these developing CAS requiring intervention. Of these 60 recipients, 22 (37%) had resolution of CAS with bronchoplasty alone, while 32 (53%) ultimately required stent placement. CAS that required intervention was not a risk factor for the development of bronchiolitis obliterans syndrome or worse overall survival. Significant risk factors for the subsequent development of CAS in a time-dependant multivariable model were pulmonary fungal infections and the need for postoperative tracheostomy. While CAS was not associated with BOS or worse survival, it remains an important complication after lung transplant with potentially preventable risk factors.

Vanishing bronchus intermedius syndrome in a pediatric patient with cystic fibrosis after lung transplantation

Airway complications occur frequently after lung transplantation. Bronchial stenosis is the most frequently encountered complication with the most severe form of that being the vanishing bronchus intermedius syndrome (VBIS). This rare disorder has never been reported in the pediatric population. This is the first report of VBIS in a pediatric patient, specifically a 16-yr-old male patient with cystic fibrosis whose course was complicated by a lower airway infection with Aspergillus fumigatus. The VBIS responded to bronchoscopic balloon dilation and placement of an airway stent.

Short-term Placement of Multiple Self-expandable Metallic Stents for the Treatment of Bilateral Bronchial Dehiscences Complicating Lung Transplantation

Bronchial dehiscence after lung transplantation is a rare complication yet has high morbidity and mortality. The majority of the patients are not surgical candidates. We present the case of a 59-year-old man with bilateral lung transplantation for interstitial pulmonary fibrosis who was readmitted with symptoms of acute rejection and severe hypoxemic respiratory failure on day 14. Bronchoscopy showed bilateral bronchial anastomotic dehiscences. A computerized tomography scan showed evidence of significant peribronchial air collection in the pleural space and the mediastinum. Owing to a high predictive operative mortality, endobronchial management was planned, and 3 uncovered self-expanding metallic stents (Ultraflex, Boston Scientific Corp) were placed (in the left main stem bronchus, the anterior segment of the right upper lobe, and the right intermediate bronchus). At 5 weeks bronchoscopy showed complete healing of the dehiscences with granulation. The stents were then removed by rigid bronchoscopy. Three weeks after the stent removal a bronchoscopic examination showed a normal tracheobronchial tree except for a slightly narrowed right anastomosis. We conclude that short-term placement of uncovered self-expanding metallic stents provides a safe and minimally invasive option in the management of bilateral dehiscences.

The management of bronchus intermedius complications after lung transplantation: a retrospective study

Background

Airway complications following lung transplantation remain a significant cause of morbidity and mortality. The management of bronchial complications in Bronchus Intermedius (BI) is challenging due to the location of right upper bronchus. The aim of this study was to analyze the results of BI Montgomery T-tube stent in a consecutive patients with lung transplantations.

Methods

Between January 2007 and December 2010, 132 lung transplantations were performed at Foch Hospital, Suresnes, France. All the patients who had BI Montgomery T-tube after lung transplantation were included in this retrospective study. The demographic and interventional data and also complications were recorded.

Results

Out of 132 lung transplant recipients, 12 patients (9 male and 3 female) were entered into this study. The indications for lung transplantation were: cystic fibrosis 8 (67%), emphysema 3 (25%), and idiopathic pulmonary fibrosis 1 (8%). Most of the patients (83%) had bilateral lung transplantation. The mean interval between lung transplantation and interventional bronchoscopy was 11.5 ± 9.8 (SD) months. There was bronchial stenosis at the level of BI in 7 patients (58.3%). The Montgomery T-tube number 10 was used in 9 patients (75%). There was statistically significant difference in Forced Expiratory Volume in one second (FEV1) before and after stent placement (p = 0.01). The most common complication after stent placement was migration (33%).

Conclusion

BI complications after lung transplantation are still a significant problem. Stenosis or malacia following lung transplantation could be well managed with modified Montgomery T-tube.

Impact of anastomotic techniques on airway complications after lung transplant

BACKGROUND

Airway complications are a source of morbidity and expense after lung transplant. Posttransplant stenosis can occur when the donor bronchus is rendered ischemic and is dependent upon collateral flow from the pulmonary capillary system. By shortening the donor bronchus, the tissue at risk for ischemia is reduced. In an effort to reduce airway complications, one surgeon at our institution began dividing the donor bronchus at the lobar carina.

METHODS

This is a retrospective analysis of all transplanted patients over the 2-year period before and after the institution of the technique change. To adjust for covariates, we performed a propensity score analysis. Outcome endpoints were postoperative airway complications, specifically, the need for therapeutic bronchoscopy, dilation, stenting, or retransplant.

RESULTS

After instituting the practice of dividing the bronchus at the lobar carina, the incidence of airway complication for the principle surgeon decreased from 13.2% (7 of 53) to 2.1% (1 of 48), resulting in an improved freedom from airway complication for that surgeon. Compared with all transplants performed during this period, the modified anastomosis resulted in fewer airway complications: 2.1% (1 of 48) versus 8.2% (19 of 231). The propensity analysis matched the 48 patients who received the modified anastomosis with 48 patients who received the standard two ring length anastomosis by surgical colleagues. The modified anastomosis group had fewer required interventions for airway complications and had significantly better freedom from airway complication when followed over time.

CONCLUSIONS

Decreasing the amount of potentially ischemic tissue implanted from the donor bronchus can reduce posttransplant airway complications.

[Lung transplantation and rejection. Basic principles, clinical aspects and histomorphology]

Lung transplantation is the ultimate therapeutical approach for the treatment of both children and adults with terminal congenital or acquired lung disease. In contrast to survival rates during the first year following transplantation, the long-term survival for patients after lung transplantation has not significantly improved in the past. In addition to other complications, acute cellular rejection constitutes a major cause for diminished function of pulmonary grafts, and can, among other factors, be causative for chronic rejection (bronchiolitis obliterans syndrome, BOS). In 2006, the International Society for Heart and Lung Transplantation (ISHLT) provided a revised version of the grading system for acute and chronic rejection of pulmonary grafts.

Reduction in airway complications after lung transplantation with novel anastomotic technique

BACKGROUND

Bronchial anastomotic complications develop in 31% of lung transplant recipients, leading to additional operative procedures and increased morbidity. Advances in surgical technique have thus far resulted in only modestly improved outcomes. We hypothesized that creating the bronchial anastomosis at the secondary carina using a combination of running and figure-of-eight sutures would minimize donor bronchial ischemia and airway complications.

METHODS

This retrospective review of a single surgeon's operative experience from 2000 to 2007 compares a new bronchial anastomotic technique with the conventional technique. The primary outcome was the occurrence of bronchial anastomotic complications requiring invasive intervention. The secondary outcome was distal airway complications. Patients were monitored for 1 year after transplant. Recipient and donor demographic data as well as relevant variables from their preoperative, perioperative, and postoperative courses were collected for analysis. These data were compared using t tests for normally distributed continuous variables, Mann-Whitney tests for nonnormally distributed continuous variables, and χ2 tests or Fisher exact test for categoric variables. Logistic regression was used to control for covariates while comparing the primary outcome between the new and conventional bronchial anastomotic techniques.

RESULTS

The analysis included 230 patients, representing 407 anastomoses. The occurrence of anastomotic complications requiring intervention and distal airway complications decreased from 18.1% to 2.3% of anastomoses and 12.2% to 4.4% of patients, respectively. After controlling for available risk factors, the new technique significantly reduced both anastomotic (p<0.001) and distal (p=0.03) airway complications.

CONCLUSIONS

This new anastomotic technique dramatically reduces anastomotic and distal airway complications after lung transplantation.