Neurodevelopmental correlates of caudate volume in children born at risk of neonatal hypoglycaemia

BACKGROUND

Neonatal hypoglycaemia can lead to brain damage and neurocognitive impairment. Neonatal hypoglycaemia is associated with smaller caudate volume in the mid-childhood. We investigated the relationship between neurodevelopmental outcomes and caudate volume and whether this relationship was influenced by neonatal hypoglycaemia.

METHODS

Children born at risk of neonatal hypoglycaemia ≥36 weeks' gestation who participated in a prospective cohort study underwent neurodevelopmental assessment (executive function, academic achievement, and emotional-behavioural regulation) and MRI at age 9-10 years. Neonatal hypoglycaemia was defined as at least one hypoglycaemic episode (blood glucose concentration <2.6 mmol/L or at least 10 min of interstitial glucose concentrations <2.6 mmol/L). Caudate volume was computed using FreeSurfer.

RESULTS

There were 101 children with MRI and neurodevelopmental data available, of whom 70 had experienced neonatal hypoglycaemia. Smaller caudate volume was associated with greater parent-reported emotional and behavioural difficulties, and poorer prosocial behaviour. Caudate volume was significantly associated with visual memory only in children who had not experienced neonatal hypoglycaemia (interaction p = 0.03), but there were no other significant interactions between caudate volume and neonatal hypoglycaemia.

CONCLUSION

Smaller caudate volume is associated with emotional behaviour difficulties in the mid-childhood. Although neonatal hypoglycaemia is associated with smaller caudate volume, this appears not to contribute to clinically relevant neurodevelopmental deficits.

IMPACT

At 9-10 years of age, caudate volume was inversely associated with emotional-behavioural difficulties and positively associated with prosocial behaviour but was not related to executive function or educational achievement. Previous studies have suggested that neonatal hypoglycaemia may contribute to smaller caudate volume but exposure to neonatal hypoglycaemia did not appear to influence the relationship between caudate volume and behaviour. Among children not exposed to neonatal hypoglycaemia, caudate volume was also positively associated with visual memory, but no such association was detected among those exposed to neonatal hypoglycaemia. Understanding early-life factors that affect caudate development may provide targets for improving behavioural function.

Spatial Relationship of Maxillary Posterior Teeth with Maxillary Sinus Floor in Sagittal, Coronal and Axial Planes by Using Cone-Beam Computed Tomography in a Subpopulation of Central India

Inadvertent perforation of the root apex during endodontic procedure in maxillary posterior teeth may unnecessarily invite the complications of sinusitis or inflammatory responses. This becomes even more important when performing endodontic surgical procedures. Thus, it is mandatory to have the precise knowledge of anatomic structures which are in close proximity to the apex of roots and its variations among different geographic area. This retrospective observational study was performed in the Central India to assess the spatial relationships between the maxillary second pre-molar (sPM), maxillary first molar (M1), maxillary second molar (M2) with the maxillary sinus floor using cone beam computed tomography (CBCT) in all three axial, sagittal and coronal sections from year 2016 to 2021. Three hundred and sixty teeth were examined through sixty full volumes CBCT scans of the patients in between year 2016-2021 in Indore, (MP, India). The Distances (D) between the examined roots and the sinus floor, were evaluated using CBCT in all three sections, and grouped in 7 classes. To simplify, Class 1 and 2 were grouped as Negative Configuration where apices are protruding into sinus floor, Class 3 as Zero and Class 4-7 as Positive configuration. The data were analyzed statistically using SPSS system. The prevalence of class 1 and 2 (negative configuration) was the highest for the Palatal of M1 (16.67%) followed by Distobuccal of M1 (13.34%). The prevalence of class 3 that is Zero configuration was the highest for the Mesiobuccal of M2 (63.33%). The results suggested all the three teeth roots showed closed proximity with sinus floor, closest relationship with the sinus floor was seen in palatal of M1 in this study.

Gallium protoporphyrin as an antimicrobial for non-typeable Haemophilus influenzae in COPD patients

AIMS

Colonisation with non-typeable Haemophilus influenzae (NTHi) is common in COPD. Iron is required by bacteria for nutrition. Gallium is imported into bacteria using iron import proteins. Gallium cannot fulfill key metabolic functions, causing bactericidal effects. We tested the efficacy of gallium compounds as antimicrobials against NTHi in hemin rich conditions, and their ability to reduce NTHi induced pro-inflammatory responses in macrophages.

MAIN METHODS

NTHi was cultured with the free iron analogue gallium nitrate (GaN) and heme iron analogue gallium protoporphyrin (GaPP) (0.5-4 μM; 24 h). Growth of NTHi reference strain (NCTC 12699) and 6 clinical isolates from COPD patients (including antibiotic resistant isolates) was assessed by optical density, and viability by Miles Misra. Monocyte derived macrophages (MDMs) were treated with GaPP before/after NTHi exposure. Viable intracellular NTHi was assessed by gentamicin protection assay. GaN or GaPP was added to NTHi cultures prior to culture with MDMs. Cytokine gene expression (qPCR) and protein secretion (ELISA) were measured.

KEY FINDINGS

NTHi growth and viability were reduced by GaPP but not GaN. GaPP inhibited growth of COPD isolates (4 μM: 87 % reduction). GaPP reduced intracellular viability of NTHi in macrophage infection models. MDM cytokine gene expression and protein secretion (TNF-α, IL-6 and CXCL8) in response to NTHi was reduced (82, 66 and 86 % for gene expression) when cultured with GaPP 4 μM.

SIGNIFICANCE

GaPP is an effective antimicrobial for NTHi while GaN showed no effect on growth or viability. Culture of NTHi with GaPP also reduced the pro-inflammatory cytokine response in MDMs.

107 A Rare Presentation of a Giant, Multi-Compartmental Lipoma of the Hand Causing Median Nerve Compression

Lipomas are the commonest benign tumour, made up exclusively of adipose tissue, and can arise anywhere in the body. However, giant lipomas of the hand, defined as greater than 5cm in diameter, are rare. They have the potential to invade and cause a multitude of symptoms due to the compression and proximity of underlying structures.

We describe a case of a 64-year-old woman who presents with a swelling of the left thenar eminence, associated with numbness and tingling in all fingers.

MRI and nerve conduction studies confirmed the diagnosis of a lipoma causing median nerve compression. The patient underwent elective surgical excision using a volar approach, with good postoperative recovery. The excised lesion, measuring 12x7x2.4cm, is the largest giant lipoma of the hand reported in literature, and the first to demonstrate invasion from the mid palmar space into both the dorsal sub-aponeurotic space and carpal tunnel.

Space occupying lesions, such as giant lipomas of the hand, are a rare but important secondary cause of compression neuropathies of the upper extremity and must be suspected when these neuropathies present with atypical symptomatology. Any patient presenting with a soft-tissue lesion of the hand demonstrating rapid growth, pain or large size must be thoroughly investigated to rule out malignancy. MRI forms an essential part of the workup in such cases due to its high diagnostic accuracy. Malignant transformation of giant lipomas of the hand is extremely rare, and such lesions can be removed by en bloc marginal resection with excellent postoperative results.

709 Two-Layer Biodegradable Temporizing Matrix Reconstruction of Abdominal Wall Dermatofibrosarcoma Protuberans

Dermatofibrosarcoma protuberans (DFSP) is a rare, locally invasive dermal sarcoma. The management is generally surgical, with wide local excision (WLE) forming the mainstay of treatment. Large abdominal wall defects are most aesthetically reconstructed using pedicled or free flaps; however, these require tumour-free surgical margins, and can cause donor site morbidity. We describe an alternative, aesthetic, and low-morbidity technique for abdominal wall reconstruction following WLE of DFSP, using 2 layers of a novel synthetic dermal matrix (NovoSorb® BTM).

25-year-old women presented with a large DFSP involving the right anterior-abdominal wall. After WLE with 3cm margins, BTM was implanted to the large sub-fascial abdominal wall defect. At 6 weeks, after histological confirmation of tumour-free margins, a second layer of BTM was applied to improve the significant contour deformity of the wound bed. After complete integration by 7 weeks, a split-thickness skin graft was harvested from the right thigh and fixed to the new dermis.

At 14-days postoperatively, the skin graft had fully taken, and donor site healed. By 8 weeks, the scar had started to mature with no obvious contour defect or contracture. Overall, the patient was satisfied with the functional and aesthetic outcome.

To our knowledge, a two-layer reconstruction using an artificial dermal matrix has never been described for abdominal wall reconstruction. We found that double-layer BTM is able to restore the inherent thickness and pliability of skin in complex abdominal wall reconstruction following WLE of DFSP and offers improved durability and cosmesis compared to skin grafting or indeed single layer skin substitutes alone.

Components of interprofessional education programs in neonatal medicine: A focused BEME review: BEME Guide No. 73

BACKGROUND

Care delivery in neonatology is dependent on an interprofessional team. Collaborative learning and education amongst professionals can lead to successful management of critically ill patients. This focused BEME review synthesized the components, outcomes, and impact of such interprofessional education (IPE) programs in neonatal medicine.

METHODS

The authors systematically searched four online databases and hand-searched MedEdPublish up to 10 September 2020. Two authors independently screened titles, abstracts, full-texts, performed data extraction and risk of bias assessment related to study methodology and reporting. Discrepancies were resolved by a third author. We reported our findings based on BEME guidance and the STORIES (STructured apprOach to the Reporting in health education of Evidence Synthesis) statement.

RESULTS

We included 17 studies on IPE in neonatal medicine. Most studies were from North America with varying learners, objectives, instruction, and observed outcomes. Learners represented nurses, respiratory therapists, neonatal nurse practitioners, patient care technicians, parents, early interventionists, physicians, and medical trainees amongst others. Risk of bias assessment in reporting revealed poor reporting of resources and instructor training. Bias assessment for study methodology noted moderate quality evidence with validity evidence as the weakest domain. IPE instruction strategies included simulation with debriefing, didactics, and online instruction. Most studies reported level 1 Kirkpatrick outcomes (76%) and few reported level 3 or 4 outcomes (23%). Challenges include buy-in from leadership and the negative influence of hierarchy amongst learners.

CONCLUSIONS

This review highlights IPE program components within neonatal medicine and exemplary practices including a multimodal instructional approach, asynchronous instruction, an emphasis on teamwork, and elimination of hierarchy amongst learners. We identified a lack of reporting on program development and instructor training. Future work should address long term knowledge and skill retention and impact on patient outcomes and organizations.

The Impact of Initial Postoperative Destination on Unplanned Critical Care Admissions After Lung Resection

OBJECTIVES

Despite an increasing proportion of patients undergoing lung resection being managed postoperatively in a ward-based environment, studies analyzing the impact of initial postoperative destination (IPD) on perioperative outcomes and unplanned critical care admission (UCCA) are lacking.

DESIGN

A single-center retrospective review.

SETTING

A cardiothoracic surgery center in the Northwest of England.

PARTICIPANTS

A total of 3,841 patients between 2012 and 2018.

INTERVENTIONS

All patients underwent lung resection. Patients were classified as either IPD ward or IPD critical care.

MEASUREMENTS AND MAIN RESULTS

Outcomes assessed included in-hospital and 90-day mortality and UCCA. Differences in mortality rates between groups were assessed using the chi-square test. Multivariate logistic regression analyses were performed to identify variables independently associated with 90-day mortality and UCCA. In total, 23.8% (n = 913) of patients went to critical care as their IPD. Overall in-hospital mortality was 1.6% (n = 62), and 90-day mortality was 2.9% (n = 112). The rate of UCCA was 10.5% (n = 404) and was significantly higher for IPD ward patients compared to IPD critical care patients (11.9% v 6.2%, p < 0.001). The 90-day mortality rates after UCCA were 5.2% (IPD ward) and 19.3% (IPD critical care) (p < 0.001). Advanced age, worse pulmonary function, IPD ward, and timing of surgery were all independently associated with UCCA.

CONCLUSIONS

Most patients undergoing lung resection can be managed safely postoperatively in a ward-based environment. Short-term mortality is higher after UCCA, with patients who experience readmission to critical care at the highest risk of death. Patients should receive additional monitoring immediately following discharge from critical care.

Multivisceral Transplant in a Patient With Portopulmonary Hypertension: A Case Report

Portopulmonary hypertension, a type of pulmonary arterial hypertension in the setting of cirrhotic or noncirrhotic portal hypertension, is associated with elevated morbidity and mortality during and after transplantation. Uncontrolled portopulmonary hypertension may prevent or delay listing for transplant candidates, and the prognosis without treatment and ultimately transplant is extremely poor. We present a 29-year-old White woman, who had a post-liver transplant at infancy due to biliary atresia. Later on, she developed extensive portal vein thrombosis and portopulmonary hypertension and underwent a multivisceral transplant (liver, stomach, pancreaticoduodenal complex, and small and large intestine). Preoperative mean pulmonary artery pressure was <30 mm Hg with a pulmonary vascular resistance of <300 dynes^.s/cm⁵ on oral sildenafil and intravenous epoprostenol. Intraoperatively, management required comprehensive transfusion protocols, a careful balance between correcting blood loss and preventing thrombosis. Intravenous epoprostenol, sildenafil, milrinone, and inhaled nitric oxide were used to reduce elevated mean pulmonary artery pressure and right ventricular strain associated with vascular clamping, reperfusion, and massive fluid shifts. Nitric oxide and epoprostenol use unleashed antiplatelet effects on a patient already susceptible to coagulopathy. A multimodal and multidisciplinary approach continued throughout the surgery and in the postoperative period, which led to a successful outcome.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Hypercalcemia with methotrexate pneumonitis: A rare, important and intriguing adverse event

Methotrexate leading to hypercalcaemia is a rarely reported adverse event. We present three elderly patients with inflammatory arthritis who developed hypercalcemia probably due to methotrexate-induced granulomatous pneumonitis. All patients presented with worsening non-productive cough with dyspnea, nausea, loss of appetite, and confusion. Their clinical and radiologic features were consistent with methotrexate-induced pneumonitis. On evaluation, all patients concurrently had hypercalcemia with normal 25OH D3, and low PTH with markedly elevated levels of 1,25OH D3 seen in two patients. In all three patients, hypercalcemia and pneumonia responded to hydration, corticosteroids, and methotrexate withdrawal. There was no relapse of symptoms on long term follow-up. In these three patients with inflammatory arthritis, methotrexate-induced pneumonitis led to symptomatic hypercalcemia. Unless hypercalcemia is looked for and treated in this setting, the morbidity can be high.

Differential responses of COPD macrophages to respiratory bacterial pathogens

COPD patients have increased susceptibility to airway bacterial colonisation. Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae are three of the most common respiratory bacterial species in COPD. H. influenzae colonisation, but not other bacteria, in COPD patients is associated with higher sputum neutrophil counts. Alveolar macrophages are key in clearance of bacteria as well as releasing mediators to recruit and activate other immune cells in response to infection. The aim was to characterise differences in COPD macrophage responses to H. influenzae, M. catarrhalisand S. pneumoniae, focusing on release of inflammatory and chemotactic mediators, and apoptosis regulation.

 Lung macrophages and monocyte-derived macrophages from COPD patients and control subjects were exposed to H. influenzae, M. catarrhalisor S. pneumoniae. Cytokine secretion (tumour necrosis factor-α, interleukin (IL)-6, CXCL8, CCL5 and IL-1β) were measured by ELISA and quantitative reverse transcriptase PCR (RT-qPCR), and apoptosis genes MCL-1, BCL-2, BAX and BAK1 by RT-qPCR. Apoptosis and reactive oxygen species (ROS) release were also measured.

 Macrophages responded differentially to the bacterial species, with increased, prolonged production of the neutrophil chemoattractant CXCL8 in response to H. influenzae and M. catarrhalis but not S. pneumoniae. S. pneumoniae initiated macrophage apoptosis and ROS release, H. influenzae and M. catarrhalis did not and increased anti-apoptosis gene expression (BCL-2 5.5-fold and MCL-1 2.4-fold, respectively).

 Differential cytokine responses of macrophages to these bacterial species can explain neutrophilic airway inflammation associated with H. influenzae, but not S. pneumoniae in COPD. Furthermore, delayed macrophage apoptosis is a potential mechanism contributing to inability to clear H. influenzae.

Differential cytokine responses of macrophages to Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae can explain neutrophilic airway inflammation associated with H. influenzae but not S. pneumoniae in COPDhttps://bit.ly/3950HVZ

1005 HEALTH-RELATED QUALITY OF LIFE AND FUTURE RISK OF HEALTH OUTCOMES AMONG OLDER ADULTS LIVING IN AUSTRALIA AND THE UNITED STATES

Introduction

Poor health-related quality of life (HRQoL) is associated with higher morbidity and mortality in patient populations. However, whether HRQoL is associated with health outcomes among community-dwelling older people requires further investigation. This study aimed to examine whether HRQoL predicts cognitive decline, dementia, cardiovascular disease (CVD), and mortality in community-dwelling older people living in Australia and the United States.

Method

A cohort of 19,106 individuals from the ASPirin in Reducing Events in the Elderly (ASPREE) study, aged 65–98 years, initially free of dementia or CVD, and who completed the HRQoL 12-item short form (SF-12, version-2) at baseline (2010–2014), were followed until June 2017. The physical (PCS) and mental component scores (MCS) of SF-12 were generated using standardized norm-based method.

Results

Over a median of 4.7 years, there were 2,412 cognitive declines, 574 dementia, 922 incident CVD events, and 1,052 deaths. Using Cox proportional-hazard regression adjusted for a range of covariates, every 10-unit increase in PCS was associated with a 6% lower risk of cognitive decline, a 14% lower risk of incident CVD, and 17% lower risk of all-cause mortality, but was not associated with incident dementia. In contrast, higher MCS was only associated with a 12% and 15% lower risk of cognitive decline and dementia, respectively. Findings did not differ by sex.

Conclusion

Our study provides some of the first evidence that HRQoL can be used in combination with clinical data to identify the future risks of health outcomes among older individuals living in the community. Our findings support the decision of the Australian Commission on Safety and Quality in Health Care to incorporate the SF-12 into the annual Patient-Reported Outcome Measures (PROMs assessment.

Is being a victim of bullying or cyberbullying in secondary school associated with subsequent risk-taking behavior in adolescence? A longitudinal study in secondary schools

INTRODUCTION

Neurobiological and social changes in adolescence can make victims of bullying more susceptible to subsequent impulsive behavior. With the high prevalence of bullying in schools and rise in cyberbullying in the United Kingdom, it is important that the health impacts of bullying victimization, including on risk-taking, are understood. Our study aims to investigate whether bullying/cyberbullying victimization is associated with subsequent health risk-taking behavior in adolescence. Risk-taking behavior includes electronic cigarette and cigarette smoking, alcohol consumption, illicit drug use, early sexual debut, weapon carrying, damaging property, and setting fire.

METHODS

A secondary quantitative analysis of data from 3337, English, secondary school students in the control arm of the INCLUSIVE trial, constituting an observational cohort. Bullying victimization was measured at baseline (age 11/12 years) using the gatehouse bullying scale and a separate question on cyberbullying victimization. Logistic regression was used to test for an association between bullying/cyberbullying victimization at baseline and risk-taking behavior at 36 months, adjusting for baseline risk-taking behavior and other potential confounders, and accounting for school clustering.

RESULTS

There was strong evidence (p ≤ .02) for a positive dose-responsive association between being bullied at baseline and nearly all risk-taking behavior at follow-up. Although there was no evidence for an association between being bullied at baseline and weapon carrying (p = .102), there was evidence for a positive association between being cyberbullied at baseline and weapon carrying (p = .036).

CONCLUSIONS

It is plausible that bullying/cyberbullying victimization increases the likelihood of subsequent risk-taking behavior in adolescence. Policy options should focus on implementing evidence-based antibullying school interventions.

COPD lung studies of Nrf2 expression and the effects of Nrf2 activators

BACKGROUND

Nrf2 regulates cellular antioxidant defence in lung cells, including epithelial cells and alveolar macrophages (AM). The Nrf2/Keap-1 pathway can be modulated by activators with different modes of action; electrophilic compounds and protein-protein interaction (PPI) inhibitors. We assessed Nrf2 and Keap-1 protein and gene levels in COPD compared to controls and the effect of Nrf2 activators on COPD AM.

METHODS

Lung resected tissue from non-smokers, smokers and COPD patients were analysed for epithelial and AM expression of Nrf2 and Keap-1 by imunoshistochemistry and by qPCR in isolated AM. AM were cultured with Nrf2 activators CDDO, C4X_6665, GSK7, MMF and Sulforaphane. Expression of Nrf2 target genes NQO1, HMOX1 SOD1 and TXNRD1 and NQO1 activity were assessed.

RESULTS

Nrf2 and Keap-1 expression was not altered in the epithelium or AM of COPD patients compared to controls. NQO1 activity was downregulated, while NQO1, HMOX1, SOD1 and TXNRD1 gene expression increased in COPD patients. All Nrf2 activators increased NQO1 activity, and NQO1, HMOX1, SOD1 and TXNRD1 expression in AMs from both COPD and smokers. The potency of C4X_6665 on NQO1 activity and regulation of Nrf2 target gene expression was higher than other compounds.

CONCLUSION

There is evidence of dysregulation of the Nrf2 signalling pathway in AM from COPD patients. The higher potency of the novel PPI Nrf2 compound C4X_6665 for inducing antioxidant activity and gene expression compared to electrophilic and other PPI Nrf2 activators highlights the therapeutic potential of this compound to address Nrf2 pathway dysregulation in COPD AM.

Heterogeneity in extracellular vesicle secretion by single human macrophages revealed by super-resolution microscopy

The diverse origins, nanometre‐scale and invasive isolation procedures associated with extracellular vesicles (EVs) mean they are usually studied in bulk and disconnected from their parental cell. Here, we used super‐resolution microscopy to directly compare EVs secreted by individual human monocyte‐derived macrophages (MDMs). MDMs were differentiated to be M0‐, M1‐ or M2‐like, with all three secreting EVs at similar densities following activation. However, M0‐like cells secreted larger EVs than M1‐ and M2‐like macrophages. Proteomic analysis revealed variations in the contents of differently sized EVs as well as between EVs secreted by different MDM phenotypes. Super resolution microscopy of single‐cell secretions identified that the class II MHC protein, HLA‐DR, was expressed on ∼40% of EVs secreted from M1‐like MDMs, which was double the frequency observed for M0‐like and M2‐like EVs. Strikingly, human macrophages, isolated from the resected lungs of cancer patients, secreted EVs that expressed HLA‐DR at double the frequency and with greater intensity than M1‐like EVs. Quantitative analysis of single‐cell EV profiles from all four macrophage phenotypes revealed distinct secretion types, five of which were consistent across multiple sample cohorts. A sub‐population of M1‐like MDMs secreted EVs similar to lung macrophages, suggesting an expansion or recruitment of cells with a specific EV secretion profile within the lungs of cancer patients. Thus, quantitative analysis of EV heterogeneity can be used for single cell profiling and to reveal novel macrophage biology.

Short-Term Outcomes of Lung Transplantation for COVID-19 ARDS: A Single Center Experience

Purpose

The outcomes of lung transplant (LTx) for COVID-19 related lung disease are continuing to be examined. This study describes our experience in the first 7 cases.

Methods

This study included all patients received double LTx (DLTx) for COVID-19 acute respiratory distress syndrome (ARDS) between November 2020 and October 2021. Patient pre-LTx and perioperative characteristics as well as post-LTx outcomes are presented.

Results

Seven patients underwent DLTx for COVID-19 ARDS. All required mechanical ventilation (MV) pre-LTx. Six patients were male (85%), 5 Hispanic (71%), with a median age of 48 (IQR 40-53) and median body mass index of 23.6 (IQR 21.7-25.6). Six patients (85%) were on veno-venous extracorporeal membrane oxygenation (VV-ECMO) pre-LTx (one conversion from VV to veno-arterial (VA)). Median duration of MV and ECMO pre-LTx was 140 days (IQR 82-165) and 71.5 days (IQR 58-149), respectively. Two patients developed acute kidney injury pre-LTx requiring continuous renal replacement therapy (CRRT). Median time from listing to transplant was 17 days (IQR 10-24). ECMO was discontinued in all but 1 patient post-LTx. Median length of stay in the hospital post-LTx was 30 days (IQR 15-57). All were discharged from the hospital (43% to rehabilitation facility). Two patients on pre-LTx CRRT remained hemodialysis dependent and had multi-drug resistant (MDR) bacterial infections post-LTx. One readmission occurred for presumed rejection, aspiration and infection with MDR Klebsiella now requiring oxygen. All surgical pathology showed diffuse interstitial fibrosis consistent with the fibrotic sequelae of alveolar damage due to COVID-19. At 3-month follow-up, 6 patients (85%) did not need supplemental oxygen and had good pulmonary function.

Conclusion

Lung transplantation for COVID-ARDS is feasible. However, pre-transplant multi-system involvement may be associated with a protracted post-LTx stay and MDR infection. Further studies are needed to assess the long-term outcomes in this cohort.