Interrupted versus continuous suture for bronchial anastomosis in lung transplantation: does it matter?

OBJECTIVES: Bronchial anastomotic complications remain a major concern in lung transplantation. We aim to compare 2 different techniques, continuous suture (CS) versus interrupted suture (IS) by analysing airway complications requiring intervention. METHODS: Lung transplantations between January 2015 and December 2020 were included. Airway complications requiring intervention were classified following the 2018 International Society for Heart and Lung Transplantation consensus and analysed comparing 3 groups of patients according to surgical technique: group A, both anastomosis performed with CS; group B, both with interrupted; and group C, IS for 1 side and CS for the contralateral side. RESULTS: A total of 461 anastomoses were performed in 245 patients. The incidence of airway complications requiring intervention was 5.7% [95% confidence interval (CI): 2.8-8.6] per patient (14/245) and 3.7% (95% CI: 2.0-5.4) per anastomosis (17/461). Complications that required intervention were present in 5 out of 164 (3.1%) anastomosis with interrupted technique, and in 12/240 (5%) with CS. No significant differences were found between techniques (P = 0.184). No statistical differences were found among group A, B or C in terms of incidence of anastomotic complications, demographics, transplant outcomes or overall survival (log-rank P = 0.513). In a multivariable analysis, right laterality was significantly associated to complications requiring intervention (OR 3.7 [95% CI: 1.1-12.3], P = 0.030). Endoscopic treatment was successful in 12 patients (85.7%). Retransplantation was necessary in 2 patients. CONCLUSIONS: In summary, although it seems that anastomotic complications requiring intervention occur more frequently with CS, there are no statistical differences compared to IS. Endoscopic treatment offers good outcomes in most of the airway complications after lung transplantation.

Lung transplantation from uncontrolled and controlled donation after circulatory death: similar outcomes to brain death donors.

Controlled donation after circulatory death donors (cDCD) are becoming a frequent source of lungs grafts worldwide. Conversely, lung transplantations (LTx) from uncontrolled donors (uDCD) are sporadically reported. We aimed to review our institutional experience using both uDCD and cDCD and compare to LTx from brain death donors (DBD). This is a retrospective analysis of all LTx performed between January 2013 and December 2019 in our institution. Donor and recipient characteristics were collected and univariate, multivariate and survival analyses were carried out comparing the three cohorts of donors. A total of 239 (84.7%) LTx were performed from DBD, 29 (10.3%) from cDCD and 14 (5%) from uDCD. There were no statistically significant differences in primary graft dysfunction grade 3 at 72 h, 30- and 90-day mortality, need for extracorporeal membrane oxygenation after procedure, ICU and hospital length of stay, airway complications, CLAD incidence or survival at 1 and 3 years after transplant (DBD: 87.1% and 78.1%; cDCD: 89.7% and 89.7%; uDCD: 85.7% and 85.7% respectively; P = 0.42). Short- and mid-term outcomes are comparable between the three types of donors. These findings may encourage and reinforce all types of donation after circulatory death programmes as a valid and growing source of suitable organs for transplantation.

Effect on the donor lungs of using abdominal normothermic regional perfusion in controlled donation after circulatory death.

OBJECTIVES: Controlled donation after circulatory death (cDCD) donors are becoming a common source of organs for transplantation globally. However, the graft survival rate of cDCD abdominal organs is inferior to that of organs from brain-dead donors. The rapid retrieval (RR) technique is used by most donor organ procurement teams. The abdominal normothermic regional perfusion (A-NRP) technique has been implemented to minimize warm ischaemic damage to the abdominal organs. However, there is limited information on the effect of A-NRP on the quality of the donor lungs. This study aimed to compare lung transplantation outcomes using lungs procured from cDCD donors using the A-NRP and abdominal RR techniques. METHODS: A single-centre retrospective analysis of consecutive transplant recipients of cDCD lungs from June 2013 to December 2019 was performed. The recipients were divided into 2 cohorts according to the abdominal procurement technique used. The recipient and donor characteristics (age, sex, cause of brain injury, warm ischaemic time, diagnosis, lung allocation score and other factors), incidence of primary graft dysfunction and early survival were monitored. RESULTS: Twenty-eight consecutive lung transplantation recipients were identified (median age 59 years; 61% male); 14 recipients received lungs using the A-NRP and 14 using abdominal RR for abdominal organ retrieval. There were no significant differences in the baseline characteristics, primary graft dysfunction (P = 0.70), hospital mortality (P = 1.0) and 1-year survival rate (P = 1.0) between the 2 groups. CONCLUSIONS: No difference was observed in lung transplantation outcomes irrespective of the abdominal organ procurement technique used (A-NRP or abdominal RR).

Thoracic surgery during the coronavirus disease 2019 (COVID-19) pandemic in Madrid, Spain: single-centre report.

OBJECTIVES: We reviewed the incidence of coronavirus disease 2019 cases and the postoperative outcomes of patients who had thoracic surgery during the beginning and at the highest point of transmission in our community. METHODS: We retrospectively reviewed patients who had undergone elective thoracic surgery from 12 February 2020 to 30 April 2020 and were symptomatic or tested positive for severe acute respiratory syndrome coronavirus 2 infection within 14 days after surgery, with a focus on their complications and potential deaths. RESULTS: Out of 101 surgical procedures, including 57 primary oncological resections, 6 lung transplants and 18 emergency procedures, only 5 cases of coronavirus disease 2019 were identified, 3 in the immediate postoperative period and 2 as outpatients. All 5 patients had cancer; the median age was 64 years. The main virus-related symptom was fever (80%), and the median onset of coronavirus disease 2019 was 3 days. Although 80% of the patients who had positive test results for severe acute respiratory syndrome coronavirus 2 required in-hospital care, none of them were considered severe or critical and none died. CONCLUSIONS: These results indicate that, in properly selected cases, with short preoperative in-hospital stays, strict isolation and infection control protocols, managed by a dedicated multidisciplinary team, a surgical procedure could be performed with a relatively low risk for the patient.

Bone Marrow-derived Mesenchymal Stem Cells and Chronic Allograft Disease in a Bronchiolitis Obliterans Animal Model.

INTRODUCTION: Bronchiolitis obliterans (BO) is the most common expression of chronic allograft dysfunction in lung transplantation. Moreover, BO represents the major cause of death in the long-term after this procedure. On the other hand, mesenchymal stem cells have been tested in animal models of BO aiming to interfere in its development. The aim of this experimental study is to explore the role of bone-marrow derived stem cells (BMSCs) as a preventive intervention of BO occurrence. MATERIALS AND METHODS: This an experimental randomized study. A bronchiolitis obliterans animal model in rats was reproduced: heterotopical tracheal transplant model in lung parenchyma. Five of these animals were used as control group. After setting up the model, individuals were divided in 3 groups of treatment (n=15), in which BMSCs were administered in 3 different time points after the tracheal transplant (tracheal transplantation and BMSCs administration occurred the same day, group G0; after 7 days, group G7; after 14 days, group G14. In addition, within each group, BMSCs were administered through 3 different routes: endotracheally, endovascular and topically in the lung parenchyma). Animals were sacrificed at 21 days. Histology, fluorescence in situ hybridization and immunohistochemistry techniques were performed for identifying stem cells. RESULTS: Compared to control group, animals receiving BMSCs showed large neovessels in a loose fibrous matrix. Group G7 showed less fibrosis (p<0.033) and edema (p<0.028). Moreover, G7 animals receiving stem cells endotracheally showed no fibrosis (p<0.008). Alveolar-like patches of tissue were observed among all groups (53.4%, 46.7% and 40% in G0, G7 and G14 respectively), consisting of cells expressing both stem and alveolar cells biomarkers. CONCLUSION: BMSCs modify the course of bronchiolitis obliterans and differentiate into alveolar cells. Endotracheal administration of BMSCs 7 days after the heterotopical tracheal transplant might be considered an effective way to prevent BO in this animal model.

Expanding the horizons: Uncontrolled donors after circulatory death for lung transplantation-First comparison with brain death donors.

Uncontrolled donation after cardiac death is an appealing source of organs for lung transplantation. We compare early and long-term outcomes of lung transplantation with these donors with a cohort of transplants from brain death donors at our institution. Retrospective analysis of all lung transplantations was performed from 2002 to 2012. We collected variables regarding recipients, donors, recover and transplant procedures, early and late complications, and survival. We included 292 lung transplants from brain death donors and 38 from uncontrolled donors after cardiac death. Both groups were comparable except for sex mismatch (male recipient-female donor was more frequent in the brain death cohort, 17.8% vs 0%, P 0.002), total ischemic time (longer for donors after cardiac death, 657 minutes for the first lung and 822 minutes for the second vs 309 and 425 minutes, P < 0.001), and ex vivo evaluation (more frequent in cardiac death donors, 21.1% vs 1.4%, P < 0.001). Early and late outcomes were not different (ICU stay [9 vs 10.5 days], hospital stay [33.5 vs 35 days], primary graft dysfunction G3 [24 vs 34.2%], and chronic graft dysfunction HR 1.19 [0.61-2.32]), but overall survival was significantly lower for patients transplanted from cardiac death donors [HR 1.67 (1.06-2.64)]. Lung transplantation after uncontrolled cardiac death offers poorer results in terms of survival compared to brain death donation. Refinement of current strategies for graft preservation and evaluation is essential to improve outcomes with this source of grafts.

Thyroid surgery at a volunteer program in Sub-Saharan Africa. / Cirugía tiroidea en programas de cooperación en África subsahariana.

INTRODUCTION: The aim of this study is to demonstrate our experience at a volunteer surgical program in Cameroon, which is of special interest given to the inability to adopt international treatment guidelines for thyroid surgery in areas of limited resources due to the lack of preoperative testing and to the difficulty to obtain sustitutive hormonal treatment. METHODS: This is a prospective observational study that includes 16 cases of thyroid surgery in Dschang (Cameroon) during June 2015. The patients were previously selected by a local medical team. All patients were black, 15 women and one man, with a mean age of 41 years. The surgical technique used for the removal of unilateral disease was hemithyroidectomy with isthmectomy and bilateral subtotal thyroidectomy for bilateral disease. RESULTS: Five subtotal thyroidectomies, 9hemithyroidectomies and 2isthmectomies were performed. Prethyroid muscles were divided only in one case. We visualized 86% of the parathyroid glands and 84% of the recurrent laryngeal nerves. The main complications observed were one symptomatic cervical haematoma that required reoperation and 2surgical wound infections. There were no clinical episodes of hypocalemia or recurrent nerve lesion. The mean length of stay was 2.3 days. At follow-up, all bilateral thyroidectomies developed high TSH levels. CONCLUSIONS: Thyroid surgery is safe in developing countries adopting protocols and techniques we use in our environment (avoiding total thyroidectomy). Bilateral thyroidectomies should not be performed unless functional studies are available in the follow-up and a thyroid hormone supplement stock guaranteed whenever necessary.

Controlled non-heart beating donor lung transplantation: initial experience in Spain.

Although the number of lung transplants in Spain is increasing annually, more organs are required to ease waiting lists. Controlled non-heart beating donors (NHBD) (Maastricht III) are a reality at international level, and contribute significantly to increasing donor numbers. In this study, we present our NHBD protocol and the initial experience in Spain using lung grafts from this type of donor. Three bilateral lung transplants were performed between January 2012 and December 2014. Preservation was by ex-vivo lung perfusion in 2 cases and by traditional cold ischemia in the other. None of the patients developed grade 3 primary graft dysfunction, no in-hospital mortality was recorded and 1-year survival was 100%. These initial results, and international experience, should help to develop similar protocols to encourage the use of controlled non-heart beating donors.

Long-term follow-up of the lung transplant patient.

Since the outcomes of lung transplants are still poorer than those obtained with others, such as heart, kidney or liver transplants, the challenge for medicine remains focused on prolonging functional graft survival. The procedure triggers significant post-surgical physiopathological changes in the lung parenchyma, the rib cage, the airways and pulmonary circulation. The patient is exposed to risks that must be identified and controlled, such as complications fully or partially attributable to immunosuppressive treatment, including cardiovascular disease, tumors and infections and, of course, chronic graft dysfunction. The patient's prognosis will depend largely on the degree of efficacy in the prevention, early diagnosis and appropriate treatment of possible complications. Accordingly, regardless of how long it is since the transplantation, graft recipients undergo close functional and clinical monitoring. In this article, we will review the functional changes that characterize a lung transplant recipient and the usefulness of the various diagnostic techniques for patient follow-up.

Heterotopic tracheal transplantation animal model of bronchiolitis obliterans: a reproducible model.

BACKGROUND: Chronic rejection or bronchiolitis obliterans (BO) is the main cause of morbidity and mortality 1 year after lung transplantation. The objective of this study was to develop a reproducible animal model that mimics the typical histological findings in human BO after lung transplantation. MATERIAL AND METHODS: We used 2 rat strains - Lewis (L) and Wistar (W) - and transplanted a segment of donor trachea into each recipient. The animals were divided into 2 groups: 1) donor and recipient of the same strain (W-W), and 2) donor and recipient of different strains (L-W). From each group, we created 4 subgroups examined at different time-points after transplantation (7, 14, 21, and 28 days). Variables were: degree of narrowing of the tracheal lumen, histological findings classified into 1 of 5 patterns, location of the ink (green or black), and presence of foreign body granuloma. RESULTS: In the W-W group, we observed a gradual onset of fibrosis, notable at 21 and 28 days post-implant. In the L-W group, obliteration of the tracheal lumen was observed in all animals, with acute inflammation by day 7, and fibrosis from then on, loose fibrosis by day 14, and frank fibrosis on days 21 and 28. Green ink was observed in vascular structures, located in granulation tissue in the early phases of the BO-type lesion, then the staining becoming less clear as the histological features developed towards frank fibrosis. This trend was seen in both groups. CONCLUSIONS: The obliteration and fibrosis are more extensive if the donor and recipient are from different strains (L-W). Histological findings in the L-W group corresponded to progressive fibrosis until day 21.

Lung transplantation with uncontrolled non-heart-beating donor. Review.

The discrepancy between organ availability and the increasing amount of patients on the waiting list has prompted the development of medical strategies to increase the usable organs, including the search for alternative sources of donation, organ optimization and extension of the criteria for donation. The recovery of lungs from non-heart-beating donors (NHBD) is a concept in which death is declared based on cardiopulmonary criteria rather than the currently used definition of "brain death." Obtaining NHBD lungs is currently practiced in many centers. In this review we discuss the current state of lung transplantation from uncontrolled NHBD.

Fulminant hyperacute rejection after unilateral lung transplantation.

Hyperacute rejection (HAR) is a well-known complication in renal and cardiac transplantation, but rare in lung recipients. We present a case of HAR of the lung graft with a fatal outcome of a male patient with preformed class II anti-HLA antibodies.

Technical modifications of the orthotopic lung transplantation model in rats with brain-dead donors.

BACKGROUND: Microsurgical lung transplantation in rats has allowed us to obtain new knowledge about lung transplantation. However, some aspects in human transplantation technique still have not been included in this model, which could interfere with the clinical interpretation and extrapolation of results. METHODS: Twenty left lung transplantations were performed with a cuff technique and technical modifications, such as brain death induction, the control of ischemia time and retrograde perfusion in the donor and the controlled sequential reperfusion of the implanted lung in the recipient. RESULTS: Survival rate was 80%. The transplanted lungs showed proper perfusion and ventilation with good permeability of the anastomoses. Signs of ischemia-reperfusion injury were observed in all animals while mild acute rejection was seen in half of them. CONCLUSIONS: The model shown proves valid and is very similar to the procedure carried out in humans, which would reduce the number of possible variables derived from the surgical technique when extrapolating the study results to clinical use.