Nuances in the interpretation and utility of donor-derived cell-free DNA in lung transplantation following allogeneic hematopoietic stem cell transplantation - Case report.

Respiratory complications following allogeneic HSCT can lead to severe morbidity and mortality. Lung transplantation (LT) is a potential treatment for select patients with late-onset non-infectious pulmonary complications post-HSCT. Donor-derived cell-free DNA (dd-cfDNA) is a noninvasive biomarker for monitoring the health of allografts following LT. However, its utility in a multi-genome setting of LT after HSCT has not yet been clinically validated. Here we describe a case of a 75-year-old, male patient who underwent single-lung transplantation for BOS related to chronic GVHD and presented with persistently elevated dd-cfDNA levels. In a surveillance biopsy, the patient was diagnosed with mild acute cellular rejection at three months. The patient's lung function remained stable, and the reported dd-cfDNA levels decreased after the rejection episode but remained elevated above levels that would be considered quiescent for LT alone. In this unique setting, as 3 different genomes contributed to the dd-cfDNA% reported value, valuable insight was obtained by performing further analysis to separate the specific SNPs to identify the contribution of recipient, lung-donor, and HSCT-donor cfDNA. This study highlights the potential utility of dd-cfDNA in the multi-genome setting of lung transplant post-HSCT, nuances that need to be considered while interpreting the results, and its value in monitoring lung rejection.

In vivo solid phase microextraction for therapeutic monitoring and pharmacometabolomic fingerprinting of lung during in vivo lung perfusion of FOLFOX.

In vivo lung perfusion (IVLP) is a novel isolated lung technique developed to enable the local, in situ administration of high-dose chemotherapy to treat metastatic lung cancer. Combination therapy using folinic acid (FOL), 5-fluorouracil (F), and oxaliplatin (OX) (FOLFOX) is routinely employed to treat several types of solid tumours in various tissues. However, F is characterized by large interpatient variability with respect to plasma concentration, which necessitates close monitoring during treatments using of this compound. Since plasma drug concentrations often do not reflect tissue drug concentrations, it is essential to utilize sample-preparation methods specifically suited to monitoring drug levels in target organs. In this work, in vivo solid-phase microextraction (in vivo SPME) is proposed as an effective tool for quantitative therapeutic drug monitoring of FOLFOX in porcine lungs during pre-clinical IVLP and intravenous (IV) trials. The concomitant extraction of other endogenous and exogenous small molecules from the lung and their detection via liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) enabled an assessment of FOLFOX's impact on the metabolomic profile of the lung and revealed the metabolic pathways associated with the route of administration (IVLP vs. IV) and the therapy itself. This study also shows that the immediate instrumental analysis of metabolomic samples is ideal, as long-term storage at -80 °C results in changes in the metabolite content in the sample extracts.

Acute transcutaneous electrical stimulation (TES) augments esophageal contractility in patients with weak peristalsis.

BACKGROUND: Lung transplantation (LTx) remains controversial in patients with absent peristalsis (AP) given the increased risk for gastroesophageal reflux (GER), and chronic lung allograft dysfunction. Furthermore, specific treatments to facilitate LTx in those with AP have not been widely described. Transcutaneous Electrical Stimulation (TES) has been reported to improve foregut contractility in LTx patients and therefore we hypothesize that TES may augment the esophageal motility of patients with ineffective esophageal motility (IEM). METHODS: We included 49 patients, 14 with IEM, 5 with AP, and 30 with normal motility. All subjects underwent standard high-resolution manometry and intraluminal impedance (HRIM) with additional swallows as TES was delivered. RESULTS: TES induced a universal impedance change observable in real-time by a characteristic spike activity. TES significantly augmented the contractile vigor of the esophagus measured by the distal contractile integral (DCI) in patients with IEM [median DCI (IQR) 0 (238) mmHg-cm-s off TES vs. 333 (858) mmHg-cm-s on TES; p = .01] and normal peristalsis [median DCI (IQR) 1545 (1840) mmHg-cm-s off TES vs. 2109 (2082) mmHg-cm-s on TES; p = .01]. Interestingly, TES induced measurable contractile activity (DCI > 100 mmHg-cm-s) in three out of five patients with AP [median DCI (IQR) 0 (0) mmHg-cm-s off TES vs. 0 (182) mmHg-cm-s on TES; p < .001]. CONCLUSION: TES acutely augmented contractile vigor in patients with normal and weak/ AP. The use of TES may positively impact LTx candidacy, and outcomes for patients with IEM/AP. Nevertheless, further studies are needed to determine the long-term effects of TES in this patient population.

A prospective examination of swallow and cough dysfunction after lung transplantation.

OBJECTIVES: Swallow and cough dysfunction are possible surgical complications of lung transplantation (LT). We examined voluntary cough strength, sensorimotor reflexive cough integrity, and swallow-related respiratory rate (RR) across swallowing safety and aspiration response groups in recovering LT recipients. METHODS: Forty-five LT recipients underwent flexible endoscopic evaluation of swallowing indexed by the validated Penetration Aspiration Scale. RR before and after a 3-ounce water drinking task was measured. Voluntary and reflexive cough screening were performed to index motor and sensory outcomes. T-tests, one-way ANOVAs, and chi-square (odds ratios) were used. RESULTS: 60% of patients exhibited laryngeal penetration (n = 27) and 40% demonstrated tracheal aspiration (n = 18); 72% (n = 13) demonstrated silent aspiration. Baseline RR was higher in aspirators versus non-aspirators (26.5 vs. 22.6, p = 0.04) and in silent aspirators compared to non-silent aspirators (27.9 vs. 20.7, p = 0.01). RR change post-swallowing did not differ between aspiration response groups; however, it was significantly higher in aspirators compared to non-aspirators (3 vs. -2, p = 0.02). Compared to non-silent aspirators, silent aspirators demonstrated reduced voluntary cough peak expiratory flow (PEF; 166 vs. 324 L/min, p = 0.01). PEF, motor and urge to cough reflex cough ratings did not differ between aspirators and non-aspirators. Silent aspirators demonstrated a 7.5 times higher odds of failing reflex cough screening compared to non-silent aspirators (p = 0.07). CONCLUSIONS: During the acute recovery period, all LT participants demonstrated some degree of unsafe swallowing and reduced voluntary cough strength. Silent aspirators exhibited elevated RR, reduced voluntary cough physiologic capacity to defend the airway, and a clinically distinguishable blunted motor response to reflex cough screening.

Corrigendum: Hyperammonemia After Lung Transplantation: Systematic Review and a Mini Case Series.

[This corrects the article DOI: 10.3389/ti.2022.10433.].

Incidence, risk factors, and sequelae of dysphagia mediated aspiration following lung transplantation.

BACKGROUND: We aimed to determine dysphagia profiles before and after lung transplantation (prevalence, incidence) and to examine predictors and health-related outcomes of aspiration in individuals undergoing lung transplantation. METHODS: A retrospective single-center study of consecutive adults undergoing lung transplantation and completing a postoperative videofluoroscopic swallowing study between 2017 and 2020 was conducted. The validated penetration aspiration scale indexed swallowing safety and clinical outcomes were extracted from electronic medical records. T-tests, chi square with odds ratios, and multivariable logistic regression were conducted. RESULTS: Two hundred five participants were identified who underwent lung transplantation and a postoperative swallowing exam. Of those who underwent both a pre- and postoperative swallowing exam (n = 170), preoperatively 83% demonstrated safe swallowing and 17% unsafe swallowing. Following lung transplantation, 16% demonstrated safe swallowing and 84% demonstrated unsafe swallowing (39% penetration, 45% aspiration). Independent predictors of postoperative aspiration were venous-venous extracorporeal membrane oxygenation (odds ratio [OR]: 6.7, confidence interval [CI]: 2.0-81.5) and reintubation (OR: 4.5, CI: 1.0-60.3), p < .05. Compared to non-aspirators, aspirators demonstrated higher odds of being discharged to a dependent care setting (OR: 2.3, CI: 1.2-4.5), p < .05. Aspirators spent significantly longer NPO (median = 138.0 hours, 25th percentile, 75th percentile = 75.7, 348.3) compared to non-aspirators (median = 85.0 hours, 25th percentile, 75th percentile = 48.0, 131.6, p < .001). CONCLUSIONS: Pre-existing dysphagia was low in this cohort of patients undergoing lung transplantation, however increased approximately 5-fold following lung transplantation and was associated with increased morbidity.

Hyperammonemia After Lung Transplantation: Systematic Review and a Mini Case Series.

Background: Hyperammonemia after lung transplantation (HALT) is a rare but serious complication with high mortality. This systematic review delineates possible etiologies of HALT and highlights successful strategies used to manage this fatal complication. Methods: Seven biomedical databases and grey literature sources were searched using keywords relevant to hyperammonemia and lung transplantation for publications between 1995 and 2020. Additionally, we retrospectively analyzed HALT cases managed at our institution between January 2016 and August 2018. Results: The systematic review resulted in 18 studies with 40 individual cases. The mean peak ammonia level was 769 µmol/L at a mean of 14.1 days post-transplant. The mortality due to HALT was 57.5%. In our cohort of 120 lung transplants performed, four cases of HALT were identified. The mean peak ammonia level was 180.5 µmol/L at a mean of 11 days after transplantation. HALT in all four patients was successfully treated using a multimodal approach with an overall mortality of 25%. Conclusion: The incidence of HALT (3.3%) in our institution is comparable to prior reports. Nonetheless, ammonia levels in our cohort were not as high as previously reported and peaked earlier. We attributed these significant differences to early recognition and prompt institution of multimodal treatment approach.

RAVAL trial: Protocol of an international, multi-centered, blinded, randomized controlled trial comparing robotic-assisted versus video-assisted lobectomy for early-stage lung cancer.

BACKGROUND: Retrospective data demonstrates that robotic-assisted thoracoscopic surgery provides many benefits, such as decreased postoperative pain, lower mortality, shorter length of stay, shorter chest tube duration, and reductions in the incidence of common postoperative pulmonary complications, when compared to video-assisted thoracoscopic surgery. Despite the potential benefits of robotic surgery, there are two major barriers against its widespread adoption in thoracic surgery: lack of high-quality prospective data, and the perceived higher cost of it. Therefore, in the face of these barriers, a prospective randomized controlled trial comparing robotic- to video-assisted thoracoscopic surgery is needed. The RAVAL trial is a two-phase, international, multi-centered, blinded, parallel, randomized controlled trial that is comparing robotic- to video-assisted lobectomy for early-stage non-small cell lung cancer that has been enrolling patients since 2016. METHODS: The RAVAL trial will be conducted in two phases: Phase A will enroll 186 early-stage non-small cell lung cancer patients who are candidates for minimally invasive pulmonary lobectomy; while Phase B will continue to recruit until 592 patients are enrolled. After consent, participants will be randomized in a 1:1 ratio to either robotic- or video-assisted lobectomy, and blinded to the type of surgery they are allocated to. Health-related quality of life questionnaires will be administered at baseline, postoperative day 1, weeks 3, 7, 12, months 6, 12, 18, 24, and years 3, 4, 5. The primary objective of the RAVAL trial is to determine the difference in patient-reported health-related quality of life outcomes between the robotic- and video-assisted lobectomy groups at 12 weeks. Secondary objectives include determining the differences in cost-effectiveness, and in the 5-year survival data between the two arms. The results of the primary objective will be reported once Phase A has completed accrual and the 12-month follow-ups are completed. The results of the secondary objectives will be reported once Phase B has completed accrual and the 5-year follow-ups are completed. DISCUSSION: If successfully completed, the RAVAL Trial will have studied patient-reported outcomes, cost-effectiveness, and survival of robotic- versus video-assisted lobectomy in a prospective, randomized, blinded fashion in an international setting. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02617186. Registered 22-September-2015. https://clinicaltrials.gov/ct2/show/NCT02617186.

Lung transplantation for acute exacerbation of interstitial lung disease.

BACKGROUND: Acute exacerbations of interstitial lung diseases (AE-ILD) have a high mortality rate with no effective medical therapies. Lung transplantation is a potentially life-saving option for patients with AE-ILD, but its role is not well established. The aim of this study is to determine if this therapy during AE-ILD significantly affects post-transplant outcomes in comparison to those transplanted with stable disease. METHODS: We conducted a retrospective study of consecutive patients with AE-ILD admitted to our institution from 2015 to 2018. The comparison group included patients with stable ILD listed for lung transplant during the same period. The primary end-points were in-hospital mortality for patients admitted with AE-ILD and 1-year survival for the transplanted patients. RESULTS: Of 53 patients admitted for AE-ILD, 28 were treated with medical therapy alone and 25 underwent transplantation. All patients with AE-ILD who underwent transplantation survived to hospital discharge, whereas only 43% of the AE-ILD medically treated did. During the same period, 67 patients with stable ILD underwent transplantation. Survival at 1 year for the transplanted patients was not different for the AE-ILD group versus stable ILD group (96% vs 92.5%). The rates of primary graft dysfunction, post-transplant hospital length-of-stay and acute cellular rejection were similar between the groups. CONCLUSION: Patients with ILD transplanted during AE-ILD had no meaningful difference in overall survival, rate of primary graft dysfunction or acute rejection compared with those transplanted with stable disease. Our results suggest that lung transplantation can be considered as a therapeutic option for selected patients with AE-ILD.