D'Cunha, Jonathan

OBJECTIVES: Pneumocystis jirovecii pneumonia (PCP) can cause severe hypoxemic respiratory failure in immunocompromised patients. Contemporary outcomes of venovenous extracorporeal membrane oxygenation (VV ECMO) support for PCP are poorly characterized, and existing reports are limited to small case series. DESIGN: Retrospective cohort study. SETTING: International registry study using the Extracorporeal Life Support Organization (ELSO) registry. PATIENTS/SUBJECTS: Adults with PCP-associated hypoxemic respiratory failure supported with VV ECMO between 2011 and 2024. INTERVENTIONS: VV ECMO. MEASUREMENTS AND MAIN RESULTS: A total of 209 patients with PCP-associated respiratory failure supported with VV ECMO were identified. The overall in-hospital mortality was 60.8%. Survivors were younger than nonsurvivors (median age 41.9 vs. 46.8 yr; p = 0.047). Duration of mechanical ventilation before VV ECMO was longer among nonsurvivors (median 4.7 vs. 1.6 d; p = 0.019). The proportion of patients with HIV infection was similar among survivors and nonsurvivors (19.5% vs. 22.1%; p = 0.73). Pre-ECMO vasopressor use, prone positioning, and renal replacement therapy were common and did not differ between groups. Clinical course was characterized by prolonged VV ECMO support (median 18.6 d) and frequent complications, including pneumothorax (21.1%), renal replacement therapy during VV ECMO (31.6%), intracranial hemorrhage or stroke (7.7%), and major pulmonary or gastrointestinal hemorrhage (16.8%). PCP accounted for a small proportion of VV ECMO runs reported to the ELSO registry throughout the study period at 0.36% of reported cases. No significant temporal trend in mortality was observed. CONCLUSIONS: PCP-associated respiratory failure supported with VV ECMO is associated with substantial mortality and prolonged VV ECMO support. These findings provide contemporary benchmarks that may inform VV ECMO candidacy discussions and expectations in this challenging patient population.

Summary Caustic esophageal injury can cause severe morbidity and mortality. Despite the need for emergent treatment, individual experience in diagnosis and management can be limited. Computed tomography (CT) has emerged as a promising non-invasive modality for assessing injury severity, but the clinical utility of both CT and endoscopy should be investigated. A systematic review was conducted following PRISMA guidelines. A comprehensive search of the PubMed database identified relevant articles published from January 1, 2000 to December 31, 2023. Inclusion criteria encompassed studies investigating the use of CT and/or endoscopy in diagnosing and managing caustic esophageal injury. Twelve articles were selected from a pool of 931 studies. Findings suggested that CT was superior in diagnostic capability to endoscopy in high-grade injury and stricture formation, but less so for low grade injuries. Diagnostic algorithms incorporating imaging with laboratory studies have emerged in the literature, which are promising pending additional validation. CT can serve as a valuable, non-invasive tool in the initial evaluation of caustic esophageal injury and is postulated to accurately predict both the need for emergent surgery and the risk of stricture formation. However, CT should not replace but rather complement the use of endoscopy to comprehensively evaluate these potentially highly morbid situations.

Mitral regurgitation (MR) in lung transplant (LTx) recipients is a rare but complex cardiopulmonary phenomenon. The overlap between symptoms of MR and post-LTx complications, such as primary graft dysfunction, complicates its diagnosis and management. This systematic review aims to characterize the incidence, pathophysiology, presentation, and management of MR in LTx patients. We conducted a literature search in PubMed, Web of Science, Scopus, and Embase. The search yielded 133 studies, of which 11 were included. Data regarding MR development, clinical presentation, echocardiographic findings, and management strategies were extracted and analyzed. Perioperative MR, occurring during or immediately post-LTx, was frequently attributed to the systolic anterior motion of the mitral valve (MV) occurring in the setting of hypovolemia and/or inotrope usage. Later postoperative MR, on the other hand, was associated with reverse ventricular remodeling and mitral annular dilation, although some variability in the literature was present. Preexisting MR or ventricular dysfunction, elongated MV leaflets, and bilateral LTx procedure appeared to be risk factors for MR development. Management was dependent on the timing of MR and its pathophysiology, where systolic anterior motion–related MR was treated with medical therapy, whereas postoperative MR often required MV interventions. In conclusion, the diagnosis of MR in LTx patients is complicated by its symptomatic overlap with other post-LTx complications. Echocardiographic monitoring in patients with preexisting MR, regardless of severity, is essential for early identification and management. Further research is needed to better understand the underlying mechanisms and refine management strategies for MR in this population.

With improved medical treatments, the prognosis for many malignancies has improved, and more patients are presenting for transplant evaluation with a history of treated cancer. Solid organ transplant (SOT) recipients with a prior malignancy are at higher risk of posttransplant recurrence or de novo malignancy, and they may require a cancer surveillance program that is individualized to their specific needs. There is a dearth of literature on optimal surveillance strategies specific to SOT recipients. A working group of transplant physicians and cancer-specific specialists met to provide expert opinion recommendations on optimal cancer surveillance after transplantation for patients with a history of malignancy. Surveillance strategies provided are mainly based on general population recurrence risk data, immunosuppression effects, and limited transplant-specific data and should be considered expert opinion based on current knowledge. Prospective studies of cancer-specific surveillance models in SOT recipients should be supported to inform posttransplant management of this high-risk population.

AbstractBackgroundThere is a knowledge gap regarding lobar versus sublobar resection for atypical carcinoid (AC) of the lung. As such, the authors sought to understand and analyze the outcomes of sublobar resection versus lobectomy in this patient population.MethodsA retrospective analysis using the National Cancer Database was performed to compare overall survival (OS) between patients treated with lobectomy and patients treated with sublobar resection for AC of the lung between the years 2004 and 2016. Patient characteristics were compared with χ2 tests. The Kaplan–Meier method was used to estimate OS distributions, and the log‐rank test was used to compare distributions by treatment strategy. A multivariable Cox regression model was used to assess associations between the treatment strategy and OS. A propensity score matching method was also implemented to further eliminate treatment selection bias in the study sample.ResultsThe database identified 669 patients with T1–T4 and N0–N3 lung ACs that were surgically resected. Unadjusted Kaplan–Meier survival curves did not demonstrate an OS difference between lobectomy and sublobar resection (p = .094). After propensity score matching, curves demonstrated a numerical improvement in OS with lobectomy; however, it was not statistically significant (p = .5). In a subgroup analysis, lobectomy and node‐negative disease were associated with the best OS, whereas sublobar resection and node‐positive disease were associated with the worst OS (p < .0001). Nodal involvement was associated with worse survival, regardless of surgical treatment (p < .0001).ConclusionsIn patients with T1–T4 and N0–N3 ACs of the lung, lobectomy was not associated with an improvement in OS in comparison with sublobar resection.

Primary graft dysfunction (PGD) is directly related to ischemia-reperfusion (I/R) injury and a major obstacle in lung transplantation (LTx). Nitrite ([Formula: see text]), which is reduced in vivo to form nitric oxide (NO), has recently emerged as an intrinsic signaling molecule with a prominent role in cytoprotection against I/R injury. Using a murine model, we provide the evidence that nitrite mitigated I/R-induced injury by diminishing infiltration of immune cells in the alveolar space, reducing pulmonary edema, and improving pulmonary function. Ultrastructural studies support severe mitochondrial impairment in the lung undergoing I/R injury, which was significantly protected by nitrite treatment. Nitrite also abrogated the increased pulmonary vascular permeability caused by I/R. In vitro, hypoxia-reoxygenation (H/R) exacerbated cell death in lung epithelial and microvascular endothelial cells. This contributed to mitochondrial dysfunction as characterized by diminished complex I activity and mitochondrial membrane potential but increased mitochondrial reactive oxygen species (mtROS). Pretreatment of cells with nitrite robustly attenuated mtROS production through modulation of complex I activity. These findings illustrate a potential novel mechanism in which nitrite protects the lung against I/R injury by regulating mitochondrial bioenergetics and vascular permeability.