Clinical Outcomes of Lung Transplants From Donors With Unexpected Pulmonary Embolism.

BACKGROUND: Pulmonary embolism (PE) is unexpectedly detected in some donor lungs during organ procurement for lung transplantation. Anecdotally, such lungs are usually implanted; however, the impact of this finding on recipient outcomes remains unclear. We hypothesized that incidentally detected donor PE is associated with adverse short-term and long-term outcomes among lung transplant recipients. METHODS: We analyzed a prospectively maintained database of all lung donors procured by a single surgeon and transplanted at our institution between 2009 and 2018. A standardized approach was used for all procurements and included antegrade and retrograde flush. Pulmonary embolism was defined as macroscopic thrombus seen in the pulmonary artery during the donor procurement operation. RESULTS: A total of 501 consecutive lung procurements were performed during the study period. The incidence of donor PE was 4.4% (22 of 501). No organs were discarded owing to PE. Donors with PE were similar to donors without PE in baseline characteristics and Pao2. Recipients in the two groups were also similar. Pulmonary embolism was associated with a higher likelihood of acute cellular rejection grade 2 or more (10 of 22 [45.5%] vs 120 of 479 [25.1%], P = .03). Multivariable Cox modeling demonstrated an association between PE and the development of chronic lung allograft dysfunction (hazard ratio 2.02; 95% confidence interval, 1.23 to 3.30; P = .005). CONCLUSIONS: Lungs from donors with incidentally detected PE may be associated with a higher incidence of recipient acute cellular rejection as well as reduced chronic lung allograft dysfunction-free survival. Surgeons must use caution when transplanting lungs with incidentally discovered PE. These preliminary findings warrant corroboration in larger data sets.

Impact of Nighttime Lung Transplantation on Outcomes and Costs.

BACKGROUND: Previous studies in the field of organ transplantation have shown a possible association between nighttime surgery and adverse outcomes. We aim to determine the impact of nighttime lung transplantation on postoperative outcomes, long-term survival, and overall cost. METHODS: We performed a single-center retrospective cohort analysis of adult lung transplant recipients who underwent transplantation between January 2006 and December 2017. Data were extracted from our institutional Lung Transplant Registry and Mid-America Transplant services database. Patients were classified into 2 strata, daytime (5 AM to 6 PM) and nighttime (6 PM to 5 AM), based on time of incision. Major postoperative adverse events, 5-year overall survival, and 5-year bronchiolitis obliterans syndrome-free survival were examined after propensity score matching. Additionally we compared overall cost of transplantation between nighttime and daytime groups. RESULTS: Of the 740 patients included in this study, 549 (74.2%) underwent daytime transplantation and 191 (25.8%) underwent nighttime transplantation (NT). Propensity score matching yielded 187 matched pairs. NT was associated with a higher risk of having any major postoperative adverse event (adjusted odds ratio, 1.731; 95% confidence interval, 1.093-2.741; P = .019), decreased 5-year overall survival (adjusted hazard ratio, 1.798; 95% confidence interval, 1.079-2.995; P = .024), and decreased 5-year bronchiolitis obliterans syndrome-free survival (adjusted hazard ratio, 1.556; 95% confidence interval, 1.098-2.205; P = .013) in doubly robust multivariable analyses after propensity score matching. Overall cost for NT and daytime transplantation was similar. CONCLUSIONS: NT was associated with a higher risk of major postoperative adverse events, decreased 5-year overall survival, and decreased 5-year bronchiolitis obliterans syndrome-free survival. Our findings suggest potential benefits of delaying NT to daytime transplantation.

Association between Allosensitization and Waiting List Outcomes among Adult Lung Transplant Candidates in the United States.

Rationale: Allosensitization may be a barrier to lung transplant. Currently, consideration is not given to allosensitization when assigning priority on the lung transplant waiting list. Objectives: We aimed to examine the association between allosensitization and waiting list outcomes. Methods: We conducted a retrospective single-center cohort study of adults listed for lung transplant at our center between January 1, 2006, and December 31, 2016. We screened candidates for human leukocyte antigen antibodies before listing and examined the association between allosensitization and waiting list outcomes, including likelihood of transplant and death on the waiting list, using a competing risk model. Calculated panel-reactive antibody (CPRA) was used as a continuous measure of allosensitization. Results: Among 746 candidates who were listed for lung transplant during the study period, 263 (35%) were allosensitized, and 483 (65%) were not. In unadjusted analysis, allosensitized candidates had a decreased likelihood of transplant compared with nonallosensitized candidates (subhazard ratio [sHR], 0.71; 95% confidence interval [CI], 0.60-0.83; P < 0.001) and were more likely to die on the waiting list (sHR, 1.66; 95% CI, 1.08-2.58; P < 0.001). In multivariable modeling, increasing CPRA was associated with an increased risk of death and a decreased likelihood of transplant (sHR for death, 1.15 per 10% increase in CPRA; 95% CI, 1.07-1.22; P < 0.001; sHR for transplant, 0.89 per 10% increase in CPRA; 95% CI, 0.86-0.91; P < 0.001). Conclusions: Broad allosensitization was associated with longer waiting times, decreased likelihood of transplant, and increased risk of death among candidates on the waiting list for lung transplant. Consideration of allosensitization in organ allocation strategies might help mitigate this increased risk in highly allosensitized candidates.

Chest computed tomography imaging improves potential lung donor assessment.

OBJECTIVE: Chest computed tomography (CT) imaging is being increasingly used for potential lung donor assessment. However, the efficacy of CT imaging in this setting remains unknown. We hypothesize that chest CT imaging independently affects the decision-making process in donor lung utilization. METHODS: We conducted a retrospective cohort study of all adult donation after brain death donors managed through our local organ procurement organization from June 2011 to November 2016. An experienced thoracic radiologist independently reviewed donor chest CT and chest x-ray images in a blinded, standardized manner to determine the presence of structural lung disease (eg, emphysema, interstitial lung disease [ILD]) and acute abnormalities (eg, traumatic lung injury [TLI]). Distinct models of lung utilization were fit to groups with initial partial pressure of oxygen (iPaO2) ≤300 mm Hg (suboptimal) and iPaO2 >300 mm Hg (optimal). RESULTS: The organ procurement organization managed 753 donors during the study period, with a lung utilization rate ([lung donors/all organ donors] × 100) of 36.5% (275 of 753). Four hundred forty-five (59.1%) donors received chest CT imaging, revealing emphysema (13.7%), ILD (2.5%), and TLI (7.2%). In univariate analysis, findings of TLI (odds ratio [OR], 2.23; 95% confidence interval [CI], 1.08-4.61) were positively associated with lung utilization, whereas findings of emphysema (OR, 0.18; CI, 0.08-0.40) were negatively associated with utilization. In multivariate analysis, CT findings of emphysema (OR, 0.21; CI 0.08-0.54) remained negatively associated with utilization. No potential donors with CT findings of ILD became lung donors. After controlling for chest x-ray findings, chest CT imaging findings of structural lung disease remained negatively associated with utilization (P = .0001). Lung utilization rate in the suboptimal and optimal iPaO2 populations was 35.1% and 41.4%, respectively, and CT findings of emphysema had a significant association with nonutilization in both groups. CONCLUSIONS: In the evaluation of potential lung donors, chest CT imaging findings of structural lung disease, such as emphysema and ILD, have a significant negative association with lung utilization. Our findings suggest that chest CT imaging might be an important adjunct to conventional lung donor assessment criteria.

Technical Considerations for Lung Transplantation in Kartagener's Syndrome.

Kartagener's syndrome is a rare genetic disorder of ciliated epithelial cells associated with recurrent respiratory tract infections, bronchiectasis, and situs inversus. In some patients, the accumulation of airway secretions and recurrent infections lead to end-stage lung disease, for which lung transplantation is the only effective treatment. Anatomical variations, such as dextrocardia and pulmonary situs inversus, make the procedure challenging, yet feasible with certain technical modifications and careful preparation of donor lungs. We report a case of bilateral lung transplantation without the use of cardiopulmonary bypass in a patient with Kartagener's syndrome while describing important technical details of the operation.

Bronchiolitis obliterans syndrome-free survival after lung transplantation: An International Society for Heart and Lung Transplantation Thoracic Transplant Registry analysis.

BACKGROUND: Lung transplant (LTx) recipients have low long-term survival and a high incidence of bronchiolitis obliterans syndrome (BOS). However, few long-term, multicenter, and precise estimates of BOS-free survival (a composite outcome of death or BOS) incidence exist. METHODS: This retrospective cohort study of primary LTx recipients (1994-2011) reported to the International Society of Heart and Lung Transplantation Thoracic Transplant Registry assessed outcomes through 2012. For the composite primary outcome of BOS-free survival, we used Kaplan-Meier survival and Cox proportional hazards regression, censoring for loss to follow-up, end of study, and re-LTx. Although standard Thoracic Transplant Registry analyses censor at the last consecutive annual complete BOS status report, our analyses allowed for partially missing BOS data. RESULTS: Due to BOS reporting standards, 99.1% of the cohort received LTx in North America. During 79,896 person-years of follow-up, single LTx (6,599 of 15,268 [43%]) and bilateral LTx (8,699 of 15,268 [57%]) recipients had a median BOS-free survival of 3.16 years (95% confidence interval [CI], 2.99-3.30 years) and 3.58 years (95% CI, 3.53-3.72 years), respectively. Almost 90% of the single and bilateral LTx recipients developed the composite outcome within 10 years of transplantation. Standard Registry analyses "overestimated" median BOS-free survival by 0.42 years and "underestimated" the median survival after BOS by about a half-year for both single and bilateral LTx (p < 0.05). CONCLUSIONS: Most LTx recipients die or develop BOS within 4 years, and very few remain alive and free from BOS at 10 years post-LTx. Less inclusive Thoracic Transplant Registry analytic methods tend to overestimate BOS-free survival. The Registry would benefit from improved international reporting of BOS and other chronic lung allograft dysfunction (CLAD) events.

Impact of Delayed Chest Closure on Surgical Site Infection After Lung Transplantation.

BACKGROUND: Delayed chest closure is an increasingly used approach in the management of bleeding and hemodynamic instability after lung transplantation. We sought to evaluate the impact of delayed chest closure on surgical site infection. METHODS: We performed a single-center retrospective cohort study and included adult patients who received a lung transplant at our center between January 1, 2010, and July 31, 2014. We defined surgical site infection as a thoracotomy incision wound or pleural space infection. Follow-up was complete through 6 months after transplantation. We used logistic regression models to examine the impact of delayed chest closure on surgical site infection and to identify other potential risk factors. RESULTS: During the study period, 67 of the 232 transplant procedures (29%) required delayed chest closure, and surgical site infection developed in 22 recipients (9%). Among the patients with surgical site infection, 18 experienced a wound infection, and 8 experienced a pleural space infection; 4 experienced concomitant wound and pleural space infection. Among the 67 who underwent delayed chest closure, 13 patients (19%) experienced a surgical site infection compared with 9 of the 165 patients (5%) who underwent primary closure (p = 0.001). In multivariate analysis, delayed chest closure was an independent risk factor for surgical site infection. CONCLUSIONS: Although delayed chest closure may have an important role in the immediate management of recipients of a lung transplant, it is an independent risk factor for surgical site infection, and this is associated with increased morbidity.

Obliterative Bronchiolitis.

Obliterative bronchiolitis (OB) is a clinical syndrome marked by progressive dyspnea and cough with the absence of parenchymal lung disease on radiographic studies. Pulmonary function testing reveals an obstructive ventilatory defect that is typically not reversed by inhaled bronchodilator. Transbronchial biopsies are insufficiently sensitive to achieve diagnosis, and in most cases, clinical, physiological, and radiological data obviate the need for the increased risk associated with open lung biopsy. This diagnosis has been documented in a variety of exposures, including fumes from flavoring plants, smoke from burn pits, and environmental sulfur gas. Among lung transplant recipients, "bronchiolitis obliterans syndrome," a disorder with clinical and histopathological similarity to OB, represents the leading cause of long-term allograft dysfunction and mortality. After hematopoietic stem cell transplantation, chronic graft versus host disease of the lung manifests most frequently with similar clinical and pathological features. In all circumstances, immunologic and nonimmunologic mechanisms are thought to lead to airway epithelial dysfunction, which results in progressive airflow obstruction and debility. Augmentation of immunosuppression is occasionally effective in slowing or reversing the progression of disease though a significant number of patients will be nonresponders. Other immunomodulatory methods have been attempted in each circumstance where this pathology has been identified. Unfortunately, OB is poorly understood and often results in sufficient progression of disease to warrant evaluation for lung transplantation (or retransplantation). Here, we review what is known regarding pathophysiology and discuss clinical, pathological, radiological, and therapeutic factors associated with the spectrum of OB-related disease with a particular focus on lung transplantation.

Other asthma considerations.

Asthma is a heterogeneous syndrome of cough, wheeze, dyspnea, and chest tightness. However, in a subset of patients, these symptoms may indicate a different underlying disease process with variable responsiveness to classic asthma therapies. Disease may progress while practitioners attempt conventional asthma therapy. Additionally, some types of asthma may require alternative approaches to relieve symptoms successfully. This article describes the differential diagnosis of asthma and discusses some of the more common asthma variants and asthma mimickers.

Hypocapnia and hypercapnia are predictors for ICU admission and mortality in hospitalized patients with community-acquired pneumonia.

OBJECTIVE: The purpose of our study was to examine in patients hospitalized with community acquired pneumonia (CAP) the association between abnormal Pa CO 2 and ICU admission and 30-day mortality. METHODS: A retrospective cohort study was conducted at two tertiary teaching hospitals. Eligible subjects were admitted with a diagnosis of CAP. Arterial blood gas analyses were obtained with measurement of PaCO2 on admission. Multivariate analyses were performed using 30-day mortality and ICU admission as the dependent measures. RESULTS: Data were abstracted on 453 subjects with a documented arterial blood gas analysis. One hundred eighty-nine patients (41%) had normal PaCO2 (35-45 mm Hg), 194 patients (42%) had aPa CO 2 , 35 mm Hg (hypocapnic), and 70 patients (15%) had a Pa CO 2 . 45 mm Hg (hypercapnic).In the multivariate analysis, after adjusting for severity of illness, hypocapnic patients had greater 30-day mortality (OR= 2.84; 95% CI, 1.28-6.30) and a higher need for ICU admission (OR= 2.88;95% CI, 1.68-4.95) compared with patients with normal PaCO2. In addition, hypercapnic patients had a greater 30-day mortality (OR= 3.38; 95% CI, 1.38-8.30) and a higher need for ICU admission(OR =5.35; 95% CI, 2.80-10.23). When patients with COPD were excluded from the analysis,the differences persisted between groups. CONCLUSION: In hospitalized patients with CAP, both hypocapnia and hypercapnia were associated with an increased need for ICU admission and higher 30-day mortality. These findings persisted after excluding patients with CAP and with COPD. Therefore, PaCO2 should be considered for inclusion in future severity stratification criteria to appropriate identified patients who will require a higher level of care and are at risk for increased mortality.