Impact of changes in skeletal muscle mass and quality during the waiting time on outcomes of lung transplantation

INTRODUCTION

The association of changes in skeletal muscle mass and quality during the waiting time with outcomes of lung transplantation (LT) remains unclear. We aimed to examine the association of changes in skeletal muscle mass and quality during the waiting time, as well as preoperative skeletal muscle mass and quality, with outcomes of LT.

METHODS

This study included individuals who underwent LT from brain-dead donors. Skeletal muscle mass (cm2 /m2 ) and quality (mean Hounsfield units [HU]) of the erector spinae muscle at the 12th thoracic level were evaluated using computed tomography. Preoperative skeletal muscle mass and quality, and their changes during the waiting time were calculated. We evaluated the associations among mechanical ventilation (MV) duration, intensive care unit (ICU) length of stay (LOS), hospital LOS, 6-minute walk distance at discharge, and 5-year survival after LT.

RESULTS

This study included 98 patients. The median waiting time was 594.5 days (interquartile range [IQR], 355.0-913.0). The median changes in skeletal muscle mass and quality were -4.4% (IQR, -13.3-3.1) and -2.9% (IQR, -16.0-4.1), respectively. Severe low skeletal muscle mass at LT was associated with prolonged ICU LOS (B = 8.46, 95% confidence interval [CI]: .51-16.42) and hospital LOS (B = 36.00, 95% CI: 3.23-68.78). Pronounced decrease in skeletal muscle mass during the waiting time was associated with prolonged MV duration (B = 7.85, 95% CI: .89-14.81) and ICU LOS (B = 7.97, 95% CI: .83-15.10).

CONCLUSION

Maintaining or increasing skeletal muscle mass during the waiting time would be beneficial to improve the short-term outcomes of LT.

Textbook Outcome: Definition and Analysis of a Novel Quality Measure in Lung Transplantation

OBJECTIVE

To define textbook outcome (TO) for lung transplantation (LTx) using a contemporary cohort from a high-volume institution.

SUMMARY BACKGROUND DATA

TO is a standardized, composite quality measure based on multiple postoperative endpoints representing the ideal "textbook" hospitalization.

METHODS

Adult patients who underwent LTx at our institution between 2016 and 2019 were included. TO was defined as freedom from intraoperative complication, postoperative reintervention, 30-day intensive care unit or hospital readmission, length of stay >75th percentile of LTx patients, 90 day mortality, 30-day acute rejection, grade 3 primary graft dysfunction at 48 or 72 hours, postoperative extracorporeal membrane oxygenation, tracheostomy within 7 days, inpatient dialysis, reintubation, and extubation >48 hours post-transplant. Recipient, operative, financial characteristics, and post-transplant outcomes were recorded from institutional data and compared between TO and non-TO groups.

RESULTS

Of 401 LTx recipients, 97 (24.2%) achieved TO. The most common reason for TO failure was extubation >48 hours post-transplant (N = 119, 39.1%); the least common was mortality (N = 15, 4.9%). Patient and graft survival were improved among patients who achieved versus failed TO (patient survival: log-rank P < 0.01; graft survival: log-rank P < 0.01). Rejection-free and chronic lung allograft dysfunction-free survival were similar between TO and non-TO groups (rejection-free survival: log-rank P = 0.07; chronic lung allograft dysfunction-free survival: log-rank P = 0.3). On average, patients who achieved TO incurred approximately $638,000 less in total inpatient charges compared to those who failed TO.

CONCLUSIONS

TO in LTx was associated with favorable post-transplant outcomes and significant cost-savings. TO may offer providers and patients new insight into transplant center quality of care and highlight areas for improvement.

Lung Transplantation Advanced Prediction Tool: Determining Recipient's Outcome for a Certain Donor

BACKGROUND

Many risk-prediction models for lung transplantation are centered on recipient characteristics and do not account for impact of donor and transplant-related factors or only examine short-term outcomes (eg, predicted 1-y survival). We sought to develop a comprehensive model guiding recipient-donor matching.

METHODS

We identified double lung transplant recipients (≥12 y old) in the United Network for Organ Sharing Registry (2005-2020) to develop a risk scoring tool. Cohort was divided into derivation and validation sets. A total of 42 recipient, donor, and transplant factors were included in the analysis. Lasso method was used for variable selection. Survival was estimated using Cox-proportional hazard models. An interactive web-based tool was developed for clinical use.

RESULTS

A derivation cohort (n = 10 660) informed the model with 13-recipient, 4-donor, and 2-transplant variables. Adjusted risk scores were computed for every transplant and grouped into 3 clusters. Model-estimated survival probabilities were similar to the observed in the validation cohort (n = 4464) for all clusters. The mortality increases for medium- and high-risk groups was similar in both derivation and validation cohorts (C statistics for 1-, 5-, and 10-y survival were 0.67, 0.64, and 0.72, respectively). The web-based application estimated 1-, 5-, 10-y survival and half-life for low- (92%, 73%, 52%; 10.5 y), medium- (89%, 62%, 38%; 7.3 y), and high-risk clusters (85%, 52%, 26%; 5.2 y).

CONCLUSIONS

Advanced methods incorporating machine/deep learning led to a risk scoring model (including recipient, donor, and transplant factors) and a web-based clinical tool providing short- and long-term survival probabilities for recipient-donor matches. This will enable risk-based matching that could improve utilization of and benefit from a limited donor pool.

Volatile organic compound profiling to explore primary graft dysfunction after lung transplantation

Primary graft dysfunction (PGD) is a major determinant of morbidity and mortality following lung transplantation. Delineating basic mechanisms and molecular signatures of PGD remain a fundamental challenge. This pilot study examines if the pulmonary volatile organic compound (VOC) spectrum relate to PGD and postoperative outcomes. The VOC profiles of 58 bronchoalveolar lavage fluid (BALF) and blind bronchial aspirate samples from 35 transplant patients were extracted using solid-phase-microextraction and analyzed with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry. The support vector machine algorithm was used to identify VOCs that could differentiate patients with severe from lower grade PGD. Using 20 statistically significant VOCs from the sample headspace collected immediately after transplantation (< 6 h), severe PGD was differentiable from low PGD with an AUROC of 0.90 and an accuracy of 0.83 on test set samples. The model was somewhat effective for later time points with an AUROC of 0.80. Three major chemical classes in the model were dominated by alkylated hydrocarbons, linear hydrocarbons, and aldehydes in severe PGD samples. These VOCs may have important clinical and mechanistic implications, therefore large-scale study and potential translation to breath analysis is recommended.

Intraoperative support during lung transplantation

The role of intraoperative mechanical support during lung transplantation (LTx) is essential to provide a safe hemodynamic and ventilatory status during critical intraoperative events. This hemodynamic and ventilatory stability is vital to minimize the odds of suboptimal outcomes, especially considering that, due to the scarcity of donors and the fact that more and more patients with significant comorbidities are being considered for this therapy, a more aggressive approach is often needed by the transplant centers. Hence, the attenuation of any potential injury that can happen during this complex event is paramount. While a thorough assessment of the donor and optimization of postoperative care is pursued, certainly protective intraoperative management would also contribute to better outcomes. Understanding each patient’s underlying anatomy and cardiopulmonary physiology, associated with awareness of critical events during a complicated procedure like LTx, is essential for a precise indication and safe use of support. Cardiopulmonary bypass (CPB) and veno-arterial extracorporeal membrane oxygenation (VA ECMO) have been the most common approaches used, with the latter gaining popularity more recently and we have used VA ECMO exclusively for the last decade. New technologies certainly contributed to more liberal use of VA ECMO intraoperatively, enabling a protecting and physiologic environment for the newly implanted grafts. In this setting, potential prophylactic use for lung protection during a critical period is also considered.

The Prognostic Role of Early Postoperative Troponin I in Lung Transplantation-A Retrospective 7-Year Analysis

OBJECTIVES

Postoperative cardiac troponin I concentration is predictive of worsened outcomes in cardiac surgery. Lung transplantation (LT) surgery shares common features with cardiac surgery, but postoperative troponin has yet to be investigated. The authors aimed to evaluate the association between early postoperative troponin concentration and the 1-year mortality after transplantation.

DESIGN

A retrospective, observational, single-center study.

SETTING

At a tertiary care, university hospital.

PARTICIPANTS

Patients who underwent lung transplantation from January 2011 to December 2017 INTERVENTIONS: For each patient, preoperative, intraoperative, and postoperative data were collected, as well as the troponin I measurement at the moment of postoperative intensive care unit admission.

MEASUREMENTS AND MAIN RESULTS

Two hundred twenty LT procedures were analyzed. Troponin I was elevated in all LT patients, with a median of 3.82 ng/mL^-1 (2-6.42) ng/mL^-1 significantly higher in non-survivors than in survivors with 5.39 (2.88-7.44) v 3.50 ng/mL (1.74-5.76), p = 0.005. In the multivariate analysis, the authors found that only the Simplified Acute Physiology Score II score (hazard ratio [HR] 1.03; 95% confidence interval [CI] [1.001; 1.05]; p = 0.007) and the need to maintain extracorporeal life support at the end of surgery (HR 2.54; 95% CI [1.36; 4.73]; p = 0.003) were independently associated with the 1-year mortality. The multiple linear regression model found that troponin levels were associated with the need for extracorporeal life support (ECLS) (p = 0.014), the amount of transfused packed red blood cells (p = 0.008), and bilateral LT (p < 0.001).

CONCLUSION

Early postoperative troponin serum levels were not independently associated with 1-year mortality. Early postoperative troponin I levels were correlated to bilateral LT, the need for ECLS, and intraoperative blood transfusion.

Inpatient Lung Transplant Evaluation Is Associated With Increased Risk of Morbidity, Mortality, and Cost of Care After Transplant

Lung transplantation is an important option for patients with end-stage lung disease. Many of these patients deteriorate rapidly and require inpatient care at the time of the transplant evaluation.

RESEARCH QUESTION

How does the setting of lung transplant evaluation relate to perioperative outcomes, short-term postoperative outcomes, and healthcare costs accrued after transplant?

DESIGN

We reviewed the records of patients who underwent primary, bilateral lung transplantation at our center between January 1, 2014 and May 31, 2016. Patient evaluation setting was categorized as inpatient, outpatient, or combined. Demographics, clinical characteristics, and cost of care were assessed.

RESULTS

The study included 207 patients: 40 (19.3%) evaluated as inpatients, 146 (70.5%) as outpatients, and 21 (10.1%) as combined. Inpatients had the highest mean lung allocation scores (71.2 vs 49.7 [combined] and 40.8 [outpatient]; P < 0.001), lowest functional status at listing (P < 0.001), highest number of blood products used during surgery (P < 0.001), highest incidence of re-exploration for bleeding (P = 0.006), and longest posttransplant hospital stays (median, 35 vs 15 days [combined] and 12 days [outpatient]; P < 0.001). One-year survival trended lower for inpatients (log-rank, P = 0.056). Inpatient evaluations had the highest total, variable, and fixed costs of posttransplant care (P < 0.001).

CONCLUSION

Inpatient lung transplant evaluation was associated with longer hospital stays, higher perioperative morbidity, and lower 1-year survival. Partial or complete inpatient evaluation was associated with a higher cost of care posttransplant.

Comparison of mechanical cardiopulmonary support strategies during lung transplantation

INTRODUCTION

Lung transplantation outcomes are influenced by the intraoperative mechanical cardiopulmonary support strategy used. This surgery was historically done either on cardiopulmonary bypass (CPB) or off pump. Recently, there has been increased interest in intraoperative support with veno-arterial (VA) or veno-venous (VV) extracorporeal membrane oxygenation (ECMO). However, there is a lack of consensus on the relative risks, benefits and indications for each intraoperative support strategy.

AREAS COVERED

This review includes information from cohort studies, case-control studies, and case series that compare morbidity and/or mortality of two or more intraoperative cardiopulmonary support strategies during lung transplantation.

EXPERT OPINION

The optimal strategy for intraoperative cardiopulmonary support during lung transplantation remains an area of debate. Current data suggest that off pump is associated with better outcomes and could be considered whenever feasible. ECMO is generally associated with preferable outcomes to CPB, but the data supporting this association is not robust. Interestingly, whether CPB is unplanned or prolonged might influence outcomes more than the use of CPB itself. These observations can help guide surgical teams in their approach for intraoperative mechanical support strategy during lung transplantation and should serve as the basis for further investigations.

Comparison of effects of propofol versus sevoflurane for patients undergoing cardiopulmonary bypass cardiac surgery

Objective

To compare the effects of propofol versus sevoflurane on the outcomes of patients undergoing cardiac surgery with cardiopulmonary bypass (CPB).

Methods

A total of 110 patients undergoing cardiac surgery with CPB in our hospital from January 2015 to June 2017 were randomly divided into 2 groups (n=55): Group A, in which anesthesia was maintained with sevoflurane, and Group B, in which anesthesia was maintained with propofol. The MMSE score before and after operation, perioperative laboratory index, incidence of postoperative cognitive dysfunction (POCD) and incidence of adverse events between the two groups were compared.

Results

The MMSE score was significantly higher in Group B than in Group A after anesthesia (p<0.05). Serum levels of the brain injury markers neuron-specific enolase, S100β and matrix metalloproteinase 9 were significantly lower in Group B than in Group A (p<0.05). POCD incidence at 12 hour and 24 hour after operation was significantly lower in Group B than in Group A (p<0.05). There were no significant differences in the incidence of low cardiac output and thoracotomy bleeding between two groups.

Conclusion

Compared with sevoflurane, the use of propofol during cardiac surgery with CPB can efficiently improve postoperative cognitive function without increasing the risk of adverse reactions.

The role of extracorporeal life support in the management with severe idiopathic pulmonary artery hypertension undergoing lung transplantation: are those patients referred too late?

Background

Idiopathic pulmonary artery hypertension (iPAH) is a relatively minor indication for lung transplantation (LTx) with comparatively poorer outcomes. Extracorporeal life support (ECLS) in various forms is increasingly being used in the management of this entity. However, the data and experience with this therapy remains limited. We evaluated the role of ECLS in the management of severe iPAH patients as a bridge to LTx as well as post LTx support.

Methods

A retrospective analysis of iPAH patients that received LTx between January 2007 and May 2014 was performed. Early- and mid-term outcomes were analyzed for this patient cohort. Also, early and mid-term outcomes after LTx were compared to the control group of patients with other diagnoses using unadjusted analysis and 1:3 propensity score matching.

Results

Of 321 LTx performed during the study period in our centre 15 patients had iPAH as a cause of end-stage lung disease. Four iPAH (27%) patients were bridged to LTx utilizing ECLS in the form of veno-arterial ECMO and extra-corporeal CO₂ removal device, whereas 9 patients (60%) required ECLS support for primary graft dysfunction (PGD) after surgery. Patients with iPAH required more frequently on-pump LTx, both pre and post LTx ECLS, and had significantly lower pO₂/FiO₂ ratio at 24, 48 and 72 hours after LTx. Also iPAH patients had significantly longer ICU and hospital stay. Whereas the incidence of postoperative bronchiolitis obliterans syndrome (BOS) and rejection was comparable to the control group, overall cumulative survival with up to 6 years follow-up was significantly poorer in the iPAH group. After propensity score matching, the results in terms of postoperative outcomes remained as in the unadjusted analysis.

Conclusions

ECLS is an essential tool in the armamentarium of any lung transplant program treating iPAH with a potential of bridge patients to transplantation and to overcome graft dysfunction after LTx. Despite utilization of ECLS in the management of iPAH, the outcomes in terms of primary graft failure and survival remain poor compared to patients with other diagnoses.

Radiological patterns of secondary sclerosing cholangitis in patients after lung transplantation

PURPOSE

The purpose of this study was to investigate the radiological patterns of secondary sclerosing cholangitis (SSC) following lung transplantation.

METHODS

Fifty-five patients underwent abdominopelvic CT before and after lung transplantation for end stage pulmonary disease. Nine patients underwent MR cholangiopancreatography (MRCP). The radiological patterns of biliary abnormalities (location, bile duct dilatation with stricture, beaded appearance, and biliary casts/sludge), laboratory data (serum total bilirubin and alkaline phosphatase), and patient survival rates were evaluated. SSC was diagnosed when there were newly developed biliary abnormalities with cholestasis after lung transplantation. Potential perioperative risk factors pertaining to SSC were analyzed. Patient survival rates with or without SSC were compared.

RESULTS

Six of the 55 patients showed imaging and laboratory findings of SSC after lung transplantation. Multifocal dilatation and stricture involved the intrahepatic (6 of 6, 100%), hilar (4 of 6, 66.7%), and extrahepatic bile duct (1 of 6, 16.7%). On CT, the lesions presented as multifocal small cyst-like lesions along the bile duct course. On MRCP, the lesions showed beaded appearance with mild duct dilatation. Preoperative mechanical ventilation and bilateral lung transplantation were associated with SSC (p < 0.05). The median survival of patients with SSC was 4.6 months.

CONCLUSION

Lung transplantation can induce SSC similar to SSC in critically ill patients, and result in worse clinical outcomes than in patients without SSC. Multifocal small cyst-like lesions along the intrahepatic bile duct on CT and beaded appearance on MRCP are suggestive findings of SSC in patients with cholestasis after lung transplantation.

Use of taurolidine in lung transplantation for cystic fibrosis and impact on bacterial colonization

OBJECTIVES

The presence of bacterial colonization that causes chronic pulmonary infections in cystic fibrosis (CF) patients remains a key issue before lung transplantation. We sought to assess the impact of intraoperative taurolidine lavage on bacterial colonization and long-term outcomes following lung transplantation in CF patients.

METHODS

Between 2007 and 2013, 114 CF patients underwent lung transplantation at our institute, and taurolidine 2% bronchial lavage was applied in a substantial proportion of patients (n = 42). A detailed analysis of donor and recipient bacterial colonization status in treatment and control groups and their impact on outcome was performed.

RESULTS

The proportion of recipients colonized with Pseudomonas aeruginosa was lower in the taurolidine group at 3 months (P < 0.001) and at 1 year (P = 0.053) postoperatively, despite no differences before transplant (P = 1.000). Moreover, a complete eradication of Burkholderia cepacia and Stenotrophomonas maltophilias colonizations could be achieved in the taurolidine group, whereas in the non-taurolidine group, persistent B. cepacia and S. maltophilias colonizations were observed. Early outcome in the taurolidine group was superior regarding fraction of expired volume in 1 s at 3 and 6 months after surgery with 74.5 ± 14.6 vs 60.4 ± 17.5 (P < 0.001) and 80.6 ± 16.9 vs 67.2 ± 19.4 (P = 0.005) percent of predicted values, respectively. In terms of long-term overall survival (P = 0.277) and freedom from bronchiolitis obliterans syndrome (P = 0.979), both groups were comparable.

CONCLUSIONS

Taurolidine might be associated with a reduced proportion of CF patients colonized with multiresistant pathogens, particularly with P. aeruginosa. Long-term results should be further assessed in larger multicentre trials.

Lung transplantation via cardiopulmonary bypass: excellent survival outcomes from extended criteria donors

OBJECTIVES

The role of intraoperative cardiopulmonary bypass (CPB) in lung transplant (LTx) surgery is controversial. CPB enables slow pulmonary reperfusion and initial ventilation with low oxygen concentrations, both theoretically protective of transplanted lungs. In this study, we explored clinical outcomes following extended criteria donor LTx surgery implementing a thoroughly protective allograft reperfusion strategy using CPB.

METHODS

Thirty-nine consecutive adult patients who underwent bilateral LTx with elective CPB and protective allograft reperfusion were reviewed. Bilaterally implanted lungs were reperfused simultaneously, via slow CPB flow reduction and initial ventilation with 21% oxygen and nitric oxide, followed by a brief modified ultrafiltration. During weaning from CPB, mean pulmonary arterial pressure was strictly maintained at 10-15 mmHg by controlling CPB and pulmonary flow. The clinical outcomes in 23 patients who received lungs from extended criteria donors (ECD group) were elucidated and compared to 16 patients undergoing LTx from standard criteria donors (SCD group).

RESULTS

No life-threatening deterioration was observed to graft functionality during the first 72 h after LTx in the ECD group; however, only one patient required post-transplant extracorporeal membrane oxygenation. In three of 23 ECD LTx patients (12%), surgical revision for bleeding was required. Survival outcomes for the ECD group were favorable, with 100% survival at 6-months, 87.0% at 1-year, and 80.7% at 5-years. Outcomes in the ECD group were comparable to those in the SCD group.

CONCLUSIONS

Despite a certain extent of risk associated with full-dose heparinization, use of CPB does not undermine survival outcomes after ECD LTx surgery if protective allograft reperfusion is securely performed.

Sequence of refusals for donor quality, organ utilization, and survival after lung transplantation

BACKGROUND

Lung donor utilization rates remain low, with many organs refused for donor quality. However, some centers have successfully transplanted these organs despite multiple refusals for donor quality (RDQs) by other centers. We hypothesized that the number of refusals due to donor quality does not impact post-transplant outcomes.

METHODS

Lung transplants (LTxs) from 2006 to 2015, identified using the United Network for Organ Sharing (UNOS) database, were matched against the potential transplant recipient (PTR) data set by donor identification. Transplants were categorized into 2 groups: low RDQ (0 to 3 RDQs) and high RDQ (>3 RDQs). Post-transplant survival and predictors for high RDQ were observed using Kaplan‒Meier and logistic regression analyses, respectively.

RESULTS

Of 10,126 adult (>18 years) LTxs, 77% had at least 1 RDQ, with a median of 4 RDQs. Post-transplant 1-year survival was similar for both the low and high RDQ groups (p = 0.49). Furthermore, groups of recipients who received donors with an increasing number of RDQs (>3, >6, or >10) also had similar post-transplant 1-year survival (p = 0.77). Treatment for rejection within 1 year and intubation at 72 hours post-transplant were higher in the high RDQ group (p < 0.01). An inverse relationship was identified between the number of RDQs and likelihood of utilization. After 10 RDQs, the likelihood of utilization varied significantly by donor characteristics.

CONCLUSIONS

Lung transplant survival is not associated with number of refusals due to donor quality. When determining whether an organ is suitable for transplant, the number of refusals due to donor quality should not influence one's decision, especially in this era of limited donor supply.

Prognostic value of pre-transplant mean pulmonary arterial pressure in lung transplant recipients: a single-institution experience

Background

Currently, lung transplantation (LTX) is considered to be a curative treatment option in patients with end-stage lung disease. Although pulmonary hypertension (PH), confirmed by cardiac catheterization, is a prognostic factor in patients undergoing LTX, the prognostic value of PH in Asian lung transplant recipients remains uncertain. In this study, we aimed to determine whether PH before LTX may serve as a prognostic factor for survival in Asian patients.

Methods

The medical records of 50 patients [male, 27; female, 23; mean age, 51.0 (41.0-60.0) years], who received preoperative right heart catheterization (RHC) and echocardiography before single or double LTX at Severance Hospital between January 2010 and December 2014, were reviewed. The relationship between 1-year survival after LTX and PH [mean pulmonary arterial pressure (mPAP) ≥25 mmHg at rest] was evaluated.

Results

The mean right ventricular systolic pressure and mPAP were 48.5 (22.8) and 30.0 (24.0-40.0) mmHg. Of the 50 patients, 17 (34.0%) died within a year after LTX. The 1-year survival rate among patients with mPAP ≥25 mmHg (58.8%) was lower than the survival rate among patients with mPAP <25 mmHg (87.5%). Pre-transplantation mPAP of ≥25 mmHg was associated with post-transplantation survival [hazard ratio (HR), 4.832; 95% confidence interval (CI), 1.080-21.608, P=0.039]. The presence of preoperative PH was also associated with an increased risk of postoperative complications.

Conclusions

Confirmation of PH via preoperative cardiac catheterization was associated with the prognosis of the patient after LTX. Clinicians should consider the necessity for early transplantation surgery before the mPAP reaches ≥25 mmHg.

Perioperative factors associated with 1-year mortality after lung transplantation: a single-center experience in Korea

Background

Most studies about the risk factors of 1-year mortality after lung transplantation were performed on non-Asians. This study aimed to evaluate the perioperative factors related to the 1-year mortality after lung transplantation in Korea.

Methods

Sixty-eight consecutive patients who underwent lung transplantation without preoperative extracorporeal membrane oxygenation treatment at 1 tertiary hospital in South Korea between October 24, 2012, and October 16, 2015, were analyzed retrospectively.

Results

Forty-four patients (64.7%) lived for >1 year after lung transplantation. The median age of all patients was 55 years (range, 16-75 years), and men accounted for 57.4%. The major cause of lung transplantation was idiopathic pulmonary fibrosis (48.5%); the other causes were interstitial lung disease related to connective tissue disease (17.6%) and bronchiolitis obliterans after stem cell transplantation (14.7%). In univariate analysis, higher median age (52 vs. 61.5 years, P<0.001), male sex (45.5% vs. 79.2%, P=0.007), lower preoperative albumin level (<3 g/dL) (22.7% vs. 45.8%, P=0.049), need for renal replacement therapy (RRT) after surgery (4.5% vs. 37.5%, P=0.001), and postoperative delta neutrophil index (DNI) >5.5 higher than the preoperative DNI (22.7% vs. 70.8%, P<0.001) were significantly related to 1-year mortality. After adjustments, old age, postoperative increased DNI, and need for RRT after transplantation were the independent perioperative risk factors for 1-year mortality after lung transplantation.

Conclusions

Recipients with advanced age should be carefully selected, and patients who need RRT or with increased DNI after transplantation should be managed accordingly.

Early and Late Atrial Arrhythmias After Lung Transplantation - Incidence, Predictive Factors and Impact on Mortality

BACKGROUND

Atrial arrhythmias (AAs) are frequent after lung transplantation (LT) and late postoperatively. Several predictive factors of early postoperative AAs after LT have been identified but those of late AAs remain unknown. Whether AA after LT affects mortality is still being debated. This study assessed in a large cohort of LT patients the incidence of AAs early and late after surgery, their predictive factors and their effect on mortality.

METHODS AND RESULTS

We studied 271 consecutive LT patients over 9 years. Mean follow-up was 2.9±2.4 years. 33% patients developed postoperative AAs. Age (odds ratio (OR) 2.35; confidence interval (CI) [1.31-4.24]; P=0.004) and chronic obstructive pulmonary disease (OR 2.13; CI [1.12-4.03]; P=0.02) were independent predictive factors of early AAs. Late AAs occurred 2.2±2.7 years after transplant in 8.8% of the patients. Pretransplant systolic pulmonary arterial pressure (PTsPAP) was the only independent predictive factor of late AA (OR 1.028; CI [1.001-1.056]; P=0.04). Double LT was associated with long-term freedom from atrial fibrillation (AF) but not from atrial flutter (AFL). Early and late AAs after surgery had no effect on mortality. Double LT was associated with better survival.

CONCLUSIONS

Early AA following LT is common in contrast with the low occurrence of late, often organized, AA. Early and late AAs do not affect mortality. PTsPAP is an independent predictor of late AA. Double LT protects against late AF but not AFL.

Hospital length of stay after lung transplantation: Independent predictors and association with early and late survival

BACKGROUND

Duration of index hospitalization after lung transplantation (LTx) is an important variable that has not received much attention. We sought to determine independent predictors of prolonged hospital length of stay (LOS) and its association with early and late outcomes.

METHODS

The United Network of Organ Sharing database was queried for adult patients undergoing LTx between 2006 and 2014 (N = 14,320). Patients with dual organ or previous transplantation and patients who died during the first 25 days after LTx were excluded (n = 12,647, mean age 55.2 years ± 13.1). Primary outcome was prolonged LOS (>25 days) (3,251/12,647; 25.7%). Donor, recipient, and procedure-related variables were analyzed as potential predictors of prolonged LOS. Association of prolonged LOS with 1-year and 5-year survival was evaluated using Cox proportional hazards analysis.

RESULTS

Independent predictors of prolonged LOS included serum albumin, lung allocation score, functional status, and need of extracorporeal membrane oxygenation or ventilator support at the time of transplant; donor age >40 years; gender mismatch (female donor to male recipient); donor body mass index; African American ethnicity; ischemic time >6 hours; and double LTx. Prolonged LOS was independently associated with increased mortality at 1 year (hazard ratio, 3.96; 95% confidence interval, 3.48-4.50; p < 0.001) and 5 years (hazard ratio, 2.00; 95% confidence interval, 1.79-2.25; p < 0.001).

CONCLUSIONS

A significant proportion of patients have a prolonged LOS after LTx, and several recipient, donor, and procedure-related variables are independent predictors of this outcome. Patients with prolonged LOS after LTx have significantly increased risk of death at 1 year and 5 years.

Prolonged Mechanical Ventilation After Lung Transplantation-A Single-Center Study

This single-center study examines the incidence, etiology, and outcomes associated with prolonged mechanical ventilation (PMV), defined as time to definite spontaneous ventilation >21 days after double lung transplantation (LTx). A total of 690 LTx recipients between January 2005 and December 2012 were analyzed. PMV was necessary in 95 (13.8%) patients with decreasing incidence during the observation period (p < 0.001). Independent predictors of PMV were renal replacement therapy (odds ratio [OR] 11.13 [95% CI, 5.82-21.29], p < 0.001), anastomotic dehiscence (OR 8.74 [95% CI 2.42-31.58], p = 0.001), autoimmune comorbidity (OR 5.52 [95% CI 1.86-16.41], p = 0.002), and postoperative neurologic complications (OR 5.03 [95% CI 1.98-12.81], p = 0.001), among others. Overall 1-year survival was 86.0% (90.4% for LTx between 2010 and 2012); it was 60.7% after PMV and 90.0% in controls (p < 0.001). Conditional long-term outcome among hospital survivors, however, did not differ between the groups (p = 0.78). Multivariate analysis identified renal replacement therapy (hazard ratio [HR] 3.55 [95% CI 2.40-5.25], p < 0.001), post-LTx extracorporeal membrane oxygenation (HR 3.47 [95% CI 2.06-5.83], p < 0.001), and prolonged inotropic support (HR 1.95 [95% CI 1.39-2.75], p < 0.001), among others, as independent predictors of mortality. In conclusion, PMV complicated 14% of LTx procedures and, although associated with increased in-hospital mortality, outcomes among patients surviving to hospital discharge were unaffected.

Outcomes of minimally invasive lung transplantation in a single centre: the routine approach for the future or do we still need clamshell incision?

OBJECTIVES

Minimally invasive lung transplantation (MILT) via bilateral anterior thoracotomies has emerged as a novel surgical strategy with potential patient benefits when compared with transverse thoracosternotomy (clamshell incision, CS). The aim of this study is to compare MILT with CS by focusing on operative characteristics, postoperative organ function and support and mid-term clinical outcomes at Harefield Hospital.

METHODS

It was a retrospective observational study evaluating all bilateral sequential lung transplants between April 2010 and November 2013.

RESULTS

CS was performed in 124 patients and MILT in 70 patients. Skin-to-skin surgical time was less in the MILT group [285 (265, 339) min] compared with CS [380 (306, 565) min] and MILT-cardiopulmonary bypass [426 (360, 478) min]. Ischaemic time was significantly longer (502 ± 116 vs 395 ± 145 min) in the MILT group compared with CS (P < 0.01). Early postoperative physiological variables were similar between groups. Patients in the MILT group required less blood [2 (0, 4) vs 3 (1, 5) units, P = 0.16] and platelet transfusion [0 (0, 1) vs 1 (0, 2) units, P < 0.01]. The median duration of mechanical ventilation was shorter (26 vs 44 h, P < 0.01) and intensive therapy unit stay was 2 days shorter (5 vs 7) in the MILT group. While overall survival was similar, fraction of expired volume in 1 s (FEV1) and forced vital capacity (FVC) were consistently higher in the MILT group compared with CS during mid-term follow-up after transplantation. Specifically, FEV1 and FVC were, respectively, 86 ± 21 and 88 ± 18% predicted in the MILT group compared with 74 ± 21 and 74 ± 19% predicted in the CS group (P < 0.01) at the 6-month follow-up.

CONCLUSIONS

MILT was successfully introduced at our centre as a novel operative strategy. Despite longer ischaemic times and a more complex operation and management, MILT appears to offer early postoperative and mid-term clinical benefits compared with our traditional approach of clamshell operations. These observations warrant larger definite studies to further evaluate the impact of MILT on physiological, clinical and patient-reported outcomes.

GORD symptoms in lung transplantation: how efficient is the reflux symptom index questionnaire compared to the esophageal impedance test?

OBJECTIVE

As Gastroesophageal reflux disease (GORD) affects long-term survival in lung transplant recipients, the aim of this observational prospective study was to analyze the efficacy of The Reflux Symptom Index Questionnaire (RSI) compared to the esophageal impedance test.

METHODS

Both esophageal impedance studies and RSI questionnaire were routinely performed in all patients who had completed rehabilitation following lung transplantation from June 2013 till March 2014. RSI generates a score of between zero and forty-five, taking into account any symptoms within four wk of the questionnaire. Our analysis considered RSI score cut-offs of 10 and 13 indicating significance of reflux.

RESULTS

Out of 84 patients, 50 (59.5%) had evidence of GORD detected by impedance studies, whereas only 33 (39.2%) and 22 (26.2%) had RSI >10 and 13, respectively. An elevated RSI was not found to be associated with positive impedance studies using a score of either 10 or 13 (p = 0.127 and p = 0.142, respectively); 32.1% (n = 27) and 40.5% (n = 34) were found to have negative RSI and positive impedance test using 10 or 13 as cut-off, respectively.

CONCLUSION

RSI Score is an unreliable predictor of GORD among lung transplant recipients. The authors therefore recommend the routine use of impedance testing in post-transplant patients.

A novel risk score that incorporates recipient and donor variables to predict 1-year mortality in the current era of lung transplantation

BACKGROUND

In this study we sought to construct a novel scoring system to pre-operatively stratify a patient's risk of 1-year mortality after lung transplantation (LTx) based on recipient- and donor-specific characteristics.

METHODS

The UNOS database was queried for adult (≥18 years) patients undergoing LTx between May 1, 2005 and December 31, 2012. The population was randomly divided in a 4:1 fashion into derivation and validation cohorts. A multivariable logistic regression model for 1-year mortality was constructed within the derivation cohort. Points were then assigned to independent predictors (p < 0.05) based on relative odds ratios. Risk groups were established based on score ranges.

RESULTS

During the study period, 9,185 patients underwent LTx and the 1-year mortality was 18.0% (n = 1,654). There was a similar distribution of variables between the derivation (n = 7,336) and validation (n = 1,849) cohorts. Of the 14 covariates included in the final model, 9 were ultimately allotted point values (maximum score = 70). The model exhibited good predictive strength (c = 0.65) in the derivation cohort and demonstrated a strong correlation between the observed and expected rates of 1-year mortality in the validation cohort (r = 0.87). The low-risk (score 0 to 11), intermediate-risk (score 12 to 21) and high-risk (score ≥22) groups had a 10.8%, 17.1% and 32.0% risk of mortality (p < 0.001), respectively.

CONCLUSIONS

This is the first scoring system that incorporates both recipient- and donor-related factors to predict 1-year mortality after LTx. Its use could assist providers in the identification of patients at highest risk for poor post-transplant outcomes.

Lung transplantation in chronic obstructive pulmonary disease: long-term survival, freedom from bronchiolitis obliterans syndrome, and factors influencing outcome

OBJECTIVES

Lung transplantation (LTx) remains the definitive treatment for end-stage lung failure, whereas chronic obstructive pulmonary disease (COPD) represents one of the main diagnoses leading to the indication for a transplant. We sought to assess long-term outcomes after LTx in patients diagnosed with COPD and analyze factors influencing outcome in this frequent patient cohort.

METHODS

Between January 2007 and November 2013, a total of 88 LTx were performed in patients with COPD in our institution. Patients with emphysema associated with alpha1-antitrypsin deficiency were excluded from this observation. The study design was a retrospective review of the prospectively collected data. A large number of pre-, intra-, and postoperative variables were analyzed including long-term survival and freedom from bronchiolitis obliterans syndrome (BOS). Furthermore, impact of different variables on survival was analyzed.

RESULTS

Preoperative donor data indicated a large proportion of marginal donors. While the overall cumulative survival after six yr was 57.4%, the results in terms of BOS-free survival in long-term follow-up were 39.7% after six yr. Patients with COPD were also associated with a low incidence (2.3%) of the need for postoperative extracorporeal life support (ECLS).

CONCLUSIONS

Long-term results after LTx in patients with COPD are acceptable with excellent survival, freedom from BOS, and low use of ECLS postoperatively despite permanently increasing proportion of marginal organs used.