Direct thrombin inhibitors fail to reverse the negative effects of heparin on lung growth and function after murine left pneumonectomy.

Neonates with congenital diaphragmatic hernia (CDH) frequently require cardiopulmonary bypass and systemic anticoagulation. We previously demonstrated that even subtherapeutic heparin impairs lung growth and function in a murine model of compensatory lung growth (CLG). The direct thrombin inhibitors (DTIs) bivalirudin and argatroban preserved growth in this model. Although DTIs are increasingly used for systemic anticoagulation clinically, patients with CDH may still receive heparin. In this experiment, lung endothelial cell proliferation was assessed following treatment with heparin-alone or mixed with increasing concentrations of bivalirudin or argatroban. The effects of subtherapeutic heparin with or without DTIs in the CLG model were also investigated. C57BL/6J mice underwent left pneumonectomy and subcutaneous implantation of osmotic pumps. Pumps were preloaded with normal saline, bivalirudin, or argatroban; treated animals received daily intraperitoneal low-dose heparin. In vitro, heparin-alone decreased endothelial cell proliferation and increased apoptosis. The effect of heparin on proliferation, but not apoptosis, was reversed by the addition of bivalirudin and argatroban. In vivo, low-dose heparin decreased lung volume compared with saline-treated controls. All three groups that received heparin demonstrated decreased lung function on pulmonary function testing and impaired exercise performance on treadmill tolerance testing. These findings correlated with decreases in alveolarization, vascularization, angiogenic signaling, and gene expression in the heparin-exposed groups. Together, these data suggest that bivalirudin and argatroban fail to reverse the inhibitory effects of subtherapeutic heparin on lung growth and function. Clinical studies on the impact of low-dose heparin with DTIs on CDH outcomes are warranted.NEW & NOTEWORTHY Infants with pulmonary hypoplasia frequently require cardiopulmonary bypass and systemic anticoagulation. We investigate the effects of simultaneous exposure to heparin and direct thrombin inhibitors (DTIs) on lung growth and pulmonary function in a murine model of compensatory lung growth (CGL). Our data suggest that DTIs fail to reverse the inhibitory effects of subtherapeutic heparin on lung growth and function. Clinical studies on the impact of heparin with DTIs on clinical outcomes are thus warranted.

A Medium-Chain Fatty Acid Analogue Prevents Intestinal Failure-Associated Liver Disease in Preterm Yorkshire Piglets.

BACKGROUND & AIMS: At least 20%-30% of patients with intestinal failure receiving long-term parenteral nutrition will develop intestinal failure-associated liver disease (IFALD), for which there are few therapeutic options. SEFA-6179 is a first-in-class structurally engineered medium-chain fatty acid analogue that acts through GPR84, PPARα, and PPARγ agonism. We hypothesized that SEFA-6179 would prevent biochemical and histologic liver injury in a preterm piglet model of IFALD. METHODS: Preterm Yorkshire piglets were delivered by cesarean section, and parenteral nutrition was provided for 14 days via implanted central venous catheters. Animals were treated with either medium-chain triglyceride vehicle control or SEFA-6179. RESULTS: Compared to medium-chain triglyceride vehicle at day of life 15, SEFA-6179 prevented biochemical cholestasis (direct bilirubin: 1.9 vs <0.2 mg/dL, P = .01; total bilirubin: 2.7 vs 0.4 mg/dL, P = .02; gamma glutamyl transferase: 172 vs 30 U/L, P = .01). SEFA-6179 also prevented steatosis (45.6 vs 13.9 mg triglycerides/g liver tissue, P = .009), reduced bile duct proliferation (1.6% vs 0.5% area cytokeratin 7 positive, P = .009), and reduced fibrosis assessed by a masked pathologist (median Ishak score: 3 vs 1, P = 0.007). RNA sequencing of liver tissue demonstrated that SEFA-6179 broadly impacted inflammatory, metabolic, and fibrotic pathways, consistent with its in vitro receptor activity (GPR84/PPARα/PPARγ agonist). CONCLUSIONS: In a preterm piglet model of IFALD, SEFA-6179 treatment prevented biochemical cholestasis and steatosis and reduced bile duct proliferation and fibrosis. SEFA-6179 is a promising first-in-class therapy for the prevention and treatment of IFALD that will be investigated in an upcoming phase II clinical trial.

A Digestive Cartridge Reduces Parenteral Nutrition Dependence and Increases Bowel Growth in a Piglet Short Bowel Model.

OBJECTIVE: To determine whether the use of an immobilized lipase cartridge (ILC) to hydrolyze fats in enteral nutrition (EN) reduces parenteral nutrition (PN) dependence in a porcine model of short bowel syndrome with intestinal failure (SBS-IF). BACKGROUND: SBS-IF occurs after intestinal loss resulting in malabsorption and PN dependence. Limited therapeutic options are available for achieving enteral autonomy. METHODS: Eleven Yorkshire piglets underwent 75% jejunoileal resection and were randomized into control (n=6) and treatment (n = 5) groups. PN was initiated postoperatively and reduced as EN advanced if predefined clinical criteria were fulfilled. Animals were studied for 14 days and changes in PN/EN calories were assessed. Intestinal adaptation, absorption, and nutrition were evaluated at the end of the study (day 15). Comparisons between groups were performed using analysis of covariance adjusted for baseline. RESULTS: ILC animals demonstrated a 19% greater reduction in PN calories ( P < 0.0001) and higher mean EN advancement (66% vs 47% of total calories, P < 0.0001) during the 14-day experiment. Treatment animals had increased intestinal length (19.5 vs 0.7%, P =0.03) and 1.9-fold higher crypt cell proliferation ( P =0.02) compared with controls. By day 15, ILC treatment resulted in higher plasma concentrations of glucagon-like peptide-2 ( P = 0.02), eicosapentaenoic acid ( P < 0.0001), docosahexaenoic acid ( P = 0.004), vitamin A ( P = 0.02), low-density lipoprotein ( P = 0.02), and high-density lipoprotein ( P = 0.04). There were no differences in liver enzymes or total bilirubin between the two groups. CONCLUSIONS: ILC use in conjunction with enteral feeding reduced PN dependence, improved nutrient absorption, and increased bowel growth in a porcine SBS-IF model. These results support a potential role for the ILC in clinical SBS-IF.

Effects of systemic anticoagulation in a murine model of compensatory lung growth.

BACKGROUND: Neonates with congenital diaphragmatic hernia (CDH) suffer from pulmonary hypoplasia (PH) and may require extracorporeal membrane oxygenation (ECMO) and anticoagulation, often with unfractionated heparin (UFH). UFH interacts with vascular endothelial growth factor (VEGF), a factor important in lung development. We investigated the effects of UFH, low molecular weight heparin (LMWH), and bivalirudin (BV) on a murine model of compensatory lung growth (CLG). METHODS: Proliferation and apoptosis were assessed in microvascular lung endothelial cells (HMVEC-L) treated with anticoagulants. Eight-week-old C57Bl/6J mice underwent left pneumonectomy and anticoagulation with low- or high-dose UFH, LMWH, BV, or saline control. Lung volume, pulmonary function tests, morphometrics, treadmill exercise tolerance, and pulmonary protein expression were examined. RESULTS: UFH and LMWH inhibited HMVEC-L proliferation. BV promoted proliferation and decreased apoptosis. UFH and LMWH-treated mice had reduced lung volume, total lung capacity, alveolar volume, and septal surface area compared to controls, while BV did not affect these measures. UFH and LMWH-treated mice had lower exercise tolerance compared to controls. CONCLUSIONS: UFH and LMWH impair pulmonary growth, alveolarization, and exercise tolerance, while BV does not. Alternative anticoagulants to heparin may be considered to improve functional outcomes for neonates with CDH and pulmonary hypoplasia. IMPACT: Unfractionated heparin and low molecular weight heparin may modify compensatory lung growth by reducing microvascular lung endothelial cell proliferation and affecting pulmonary angiogenic signaling. Functional effects of unfractionated heparin and low molecular weight heparin on murine compensatory lung growth include reduction in exercise tolerance. Bivalirudin, a direct thrombin inhibitor, may increase microvascular lung endothelial cell proliferation and preserves lung volume, alveolarization, and exercise tolerance in a murine compensatory lung growth model. Anticoagulants alternative to heparin should be further investigated for use in neonates with pulmonary hypoplastic diseases to optimize lung growth and development and improve outcomes.

Outcomes and Perioperative Nutritional Management in a Porcine Model of Short Bowel Syndrome.

INTRODUCTION: Short bowel syndrome (SBS) results from significant intestinal loss and is characterized by insufficient absorption of nutrients and fluids. Preclinical large animal SBS models typically require parenteral nutrition (PN) support and may not be appropriate for studying interventions to improve intestinal absorption or adaptation. Here, we describe the development of a porcine SBS model that does not require PN support. METHODS: Eight male Yorkshire piglets underwent either a 75% or 90% jejunoileal resection (n = 5) or no resection (n = 3). Continuous enteral nutrition (EN) was provided via a gastrostomy tube. The final SBS model consisted of a 75% resection and nutrition provided via combination EN (60%) and per oral pig chow (40%). Body weight and concentration of fat-soluble vitamins were assessed on postoperative days (POD) 7, 14, and 21. For assessing fat malabsorption, the coefficient of fat absorption (CFA) was calculated following a 72-h stool collection. RESULTS: Resected animals had decreased weight gain compared to unresected controls (POD21 + 8.3% versus +28.8%, P = 0.048). Vitamin D concentration was significantly lower in resected animals compared to controls on POD 7, POD 14, and POD 21. Serum vitamin E concentration was also lower on POD 21. Resected animals developed fat malabsorption with lower CFA (76.5% versus 95.3%, P = 0.014). CONCLUSIONS: We describe the development of a porcine SBS model that does not require PN support. Piglets in this model gain less weight, demonstrate fat malabsorption, and develop fat-soluble vitamin deficiencies. This model will benefit investigations of intestinal absorption or adaptation while potentially decreasing costs and confounding complications related to PN administration.

Time to Surgery and Thyroid Cancer Survival in the United States.

BACKGROUND: Longer time to surgery worsens survival in multiple malignancies, including lung, colorectal, and breast cancers, but limited data exist for well-differentiated thyroid cancer. We sought to investigate the impact of time to surgery on overall survival in patients with papillary thyroid cancer. METHODS: In a retrospective cohort study of the National Cancer Database, we used Cox proportional hazard models to investigate overall survival as a function of time between diagnosis and surgery for adults with papillary thyroid cancer, adjusting for demographic, patient, and cancer-related variables. Time to surgery was investigated both as a continuous variable and as intervals of 0-90 days, 90-180 days, and > 180 days. Subgroup analyses were conducted by T stage. RESULTS: Overall, 103,812 adults with papillary thyroid cancer were included from 2004 to 2016. Median follow-up was 55.2 months (interquartile range 28.4-89.5). Increasing time to surgery was associated with increased mortality: delaying by 91-180 days increased the risk by 30% (adjusted hazard ratio [aHR] 1.30, 95% CI 1.19-1.43) and delaying by over 180 days increased the risk by 94% (aHR 1.94, 95% CI 1.68-2.24). Five-year overall survival was 95.7% for 0-90 days, 93.0% for 91-180 days, and 87.9% for over 180 days. On subgroup analysis, increasing delay was associated with worse overall survival for T1, T2, and T3 tumors, but not T4 tumors. CONCLUSIONS: Increasing time to surgery in papillary thyroid cancer is associated with reduced overall survival. Further research is necessary to assess the impact of surgical delay on disease-specific survival.

Decreasing Surgical Management of Secondary Hyperparathyroidism in the United States.

BACKGROUND: Secondary hyperparathyroidism (SHPT) commonly occurs in end-stage renal disease (ESRD), leading to vascular calcification and increased mortality. For SHPT refractory to medical management, parathyroidectomy improves symptoms and decreases mortality. Medical management has changed with the release of new guidelines and advent of novel medications. We investigate recent national trends in parathyroidectomy for SHPT. MATERIALS AND METHODS: We used the National/Nationwide Inpatient Sample from 2004 to 2016 to identify hospitalizations including parathyroidectomy for SHPT and calculated parathyroidectomy rates utilizing data from the United States Renal Data System. Subgroup analysis was conducted by race. Risk factors for in-hospital mortality were identified with purposeful selection and multivariable logistic regression. RESULTS: From 2004 to 2016, the rate of parathyroidectomies for SHPT per 1000 ESRD patients decreased from 6.07 (95% CI: 4.83-7.32) to 3.67 (95% CI: 3.33-4.00). Black patients underwent parathyroidectomy for SHPT at a 1.8-fold higher rate than white and Hispanic patients (5.59 versus 3.04 and 3.07). Almost all tracked comorbidities increased in prevalence. In-hospital mortality trended lower (1.5% to 0.8%, P = 0.051). Risk factors for in-hospital mortality included weight loss (OR 4.19, 95% CI: 2.00-8.78) and cardiac arrhythmia (OR 3.38, 95% CI: 1.66-6.91), while additional calendar year (OR = 0.87, 95% CI: 0.80-0.95) was protective. CONCLUSIONS: The etiology of the declining parathyroidectomy rate for SHPT is unclear; possible factors include changing guidelines emphasizing medical management, widespread availability of cinacalcet, changing practice patterns, and inadequate surgical referral.

Inflammation drives pathogenesis of early intestinal failure-associated liver disease.

Patients with intestinal failure who receive long-term parenteral nutrition (PN) often develop intestinal failure-associated liver disease (IFALD). Although there are identified risk factors, the early pathogenesis is poorly understood and treatment options are limited. Here, we perform a transcriptomic analysis of liver tissue in a large animal IFALD model to generate mechanistic insights and identify therapeutic targets. Preterm Yorkshire piglets were provided PN or bottle-fed with sow-milk replacer for 14 days. Compared to bottle-fed controls, piglets receiving PN developed biochemical cholestasis by day of life 15 (total bilirubin 0.2 vs. 2.9 mg/dL, P = 0.01). RNA-Seq of liver tissue was performed. Ingenuity Pathway Analysis identified 747 differentially expressed genes (343 upregulated and 404 downregulated) with an adjusted P < 0.05 and a fold-change of > |1|. Enriched canonical pathways were identified, demonstrating broad activation of inflammatory pathways and inhibition of cell cycle progression. Potential therapeutics including infliximab, glucocorticoids, statins, and obeticholic acid were identified as predicted upstream master regulators that may reverse the PN-induced gene dysregulation. The early driver of IFALD in neonates may be inflammation with an immature liver; identified therapeutics that target the inflammatory response in the liver should be investigated as potential treatments.

Fat malabsorption in short bowel syndrome: A review of pathophysiology and management.

Fat malabsorption is central to the pathophysiology of short bowel syndrome (SBS). It occurs in patients with insufficient intestinal surface area and/or function to maintain metabolic and growth demands. Rapid intestinal transit and impaired bile acid recycling further contribute to fat malabsorption. A significant portion of patients require parenteral nutrition (PN) for their survival but may develop sepsis and liver dysfunction as a result. Despite advancements in the treatment of SBS, fat malabsorption remains a chronic issue for this vulnerable patient population. Peer-reviewed literature was assessed on the topic of fat malabsorption in SBS. Current management of patients with SBS involves dietary considerations, PN management, antidiarrheals, glucagon-like peptide 2 agonists, and multidisciplinary teams. Clinical trials have focused on improving intestinal fat absorption by facilitating fat digestion with pancreatic enzymes. Targeting fat malabsorption in SBS is a potential pathway to improving lifestyle and reducing morbidity and mortality in this rare disease.

Administration of 4% tetrasodium EDTA lock solution and central venous catheter complications in high-risk pediatric patients with intestinal failure: A retrospective cohort study.

BACKGROUND: Selection of central venous catheter (CVC) lock solution impacts catheter mechanical complications and central line-associated bloodstream infections (CLABSIs) in pediatric patients with intestinal failure. Disadvantages of the current clinical standards, heparin and ethanol lock therapy (ELT), led to the discovery of new lock solutions. High-risk pediatric patients with intestinal failure who lost access to ELT during a recent shortage were offered enrollment in a compassionate use trial with 4% tetrasodium EDTA (T-EDTA), a lock solution with antimicrobial, antibiofilm, and antithrombotic properties. METHODS: We performed a descriptive cohort study including 14 high-risk pediatric patients with intestinal failure receiving 4% T-EDTA as a daily catheter lock solution. CVC complications were documented (repairs, occlusions, replacements, and CLABSIs). Complication rates on 4% T-EDTA were compared with baseline rates, during which patients were receiving either heparin or ELT (designated as heparin/ELT). RESULTS: Patients initiated 4% T-EDTA at the time they were enrolled in the compassionate use protocol. Use of 4% T-EDTA resulted in a 50% reduction in CVC complications, compared with baseline rates on heparin/ELT (incidence rate ratio: 0.50; 95% CI, 0.25-1.004; P = 0.051). CONCLUSION: In a compassionate use protocol for high-risk pediatric patients with intestinal failure, the use of 4% T-EDTA reduced composite catheter complications, including those leading to emergency department visits, hospital admissions, additional procedures, and mortality. This outcome suggests 4% T-EDTA has benefits over currently available lock solutions.

Inequities in Thyroid Cancer Care: Populations Most at Risk for Delays in Diagnosis and Treatment.

Background: Delays in treatment for thyroid cancer (TC) have been associated with higher overall mortality rates. However, few studies have explored the impact of health disparities on delayed presentation and treatment for TC. This study aims to investigate what patient sociodemographic factors contribute to delays in presentation and treatment of TC. Methods: Using the National Cancer Database, we identified patients diagnosed with well-differentiated TC between 2004 and 2016 who underwent thyroidectomy. Multivariable regression analyses were conducted to examine the impact of race, insurance status, income, and distance from treatment facility on time to surgical treatment, stage, the presence of distant metastases, and tumor size. Results: We identified 89,105 patients diagnosed with well-differentiated TC who underwent thyroidectomy. Nonwhite patients who were uninsured or had Medicare or Medicaid insurance were more likely to experience delays in care, present with higher stages at diagnosis, and have distant metastases and larger tumors at presentation. Distance from treatment facility was associated with delays in surgical treatment and higher stage at presentation. Conclusion: Delays in TC presentation and surgical treatment vary by race, insurance status, and patient location. Health care policies should focus on targeting at-risk individuals to reduce health care disparities in this disease.

IMPOWER: a national patient-generated registry for intestinal malrotation exploring diagnosis, treatment, and surgical outcomes.

BACKGROUND: Intestinal malrotation is a rare congenital condition with potentially devastating consequences due to potential volvulus and massive intestinal necrosis. Diagnosis is often delayed and long-term symptoms following surgical correction are poorly characterized. We developed the Intestinal Malrotation Patient Outcomes and WEllness Registry (IMPOWER), a national patient-generated registry (PGR), to capture data related to presenting symptoms, testing, diagnosis, treatment, and follow-up of individuals diagnosed with malrotation. IMPOWER captures patient-reported information from adult patients and parents/caregivers of children diagnosed with malrotation at the time of enrollment and at ongoing 6-month intervals. We present baseline characteristics of patients enrolled during the first two months of the registry. RESULTS: Within the first two months, 354 patients with malrotation enrolled in IMPOWER, and 191 (53.9%) completed all baseline assessments. Nearly 90% of the 119 pediatric participants and 37.7% of the 72 adult participants experienced symptoms prior to diagnosis. Vomiting was the predominant symptom for pediatric participants compared to abdominal pain in adults. Yellow bilious emesis was more commonly reported than green, and volvulus at diagnosis occurred in 70% of pediatric and 27% of adult participants. One-third of pediatric participants had a bowel resection as part of their initial surgical procedure, resulting in 23.4% with diagnosed short bowel syndrome. More than 60% of pediatric and 80% of adult registrants reported gastrointestinal symptoms that persisted throughout the first year following their initial operation. Approximately 25% of registrants reported visiting four or more gastroenterologists for management of ongoing symptoms. CONCLUSIONS: Fewer than half of pediatric patients presented with the "classic" presentation of green bilious colored emesis. Yellow bilious emesis was more commonly reported, and chronic gastrointestinal symptoms (i.e., abdominal pain, reflux, constipation, diarrhea) and feeding intolerance were common following surgical procedures for malrotation. This novel PGR highlights the need for a multicenter prospective registry to characterize the natural history and develop consistent standards of care related to the diagnosis, treatment, and long-term care for patients with malrotation.

Delay in Surgery and Papillary Thyroid Cancer Survival in the United States: A SEER-Medicare Analysis.

INTRODUCTION: Delays in surgery and their impact on survival in papillary thyroid cancer (PTC) is unclear. We sought to investigate the association between time to surgery and survival in patients with PTC. METHODS: A total of 8170 Medicare beneficiaries with PTC who underwent thyroidectomy were identified within the Surveillance, Epidemiology, and End Results-Medicare linked data files between 1999 and 2018. Disease-specific survival (DSS) and overall survival (OS) were estimated using Kaplan-Meir analysis, and Cox proportional hazards models were specified to estimate the association between time to surgery and survival. RESULTS: Among 8170 patients with PTC, mean age 69.3 (SD+/- 11.4), 89.8% had surgery within the first 90 days, 7.8% had surgery 91 to 180 days from diagnosis, and 2.4% had surgery after 180 days. Increasing time to surgery was associated with increased mortality for OS in the >180-day group [adjusted hazard ratio (aHR) 1.24; 95% CI, 1.01-1.53]. Moreover, on stratification by summary stage, those with localized disease in the 91- to 180-day group increased risk by 25% (aHR 1.25; 95%CI, 1.05-1.51), and delaying over 180 days increased risk by 61% (aHR 1.61; 95%CI, 1.19-2.18) in OS. Those with localized disease in the >180-day group had almost 4 times the estimated rate of DSS mortality (aHR3.51; 95%CI, 1.68-7.32). When stratified by T stage, those with T2 disease in the >180 days group had double the estimated rate of all-cause mortality (aHR 2.0; 95% CI, 1.1-3.3) and almost triple the estimated rate of disease-specific mortality (aHR 2.7; 95% CI, 1.05-6.8). CONCLUSIONS: Delays in surgery for PTC may impact OS and DSS in localized disease, prior to nodal metastasis.

Incidence and development of cholestasis in surgical neonates receiving an intravenous mixed-oil lipid emulsion.

BACKGROUND: Intestinal failure-associated liver disease (IFALD), initially manifesting as cholestasis, is a complication in neonates receiving parenteral nutrition (PN). Soybean oil lipid emulsion (SOLE), though implicated in IFALD, was the only US Food and Drug Administration (FDA)-approved initial intravenous lipid emulsion (ILE) for infants and children in the United States. A mixed-oil lipid emulsion (MOLE) gained popularity in patients at risk for IFALD and was recently FDA approved as an initial ILE in children. Given the presence of soybean oil in MOLE, we hypothesized that MOLE would not be effective at preventing cholestasis in surgical neonates. METHODS: Neonates with gastrointestinal surgical conditions necessitating PN for ≥14 days and receiving MOLE (SMOFlipid) from July 2016 to July 2019 were analyzed retrospectively. Unpaired and pair-matched historical surgical neonates treated with SOLE (Intralipid) served as controls. The primary outcome measure was development of cholestasis (direct bilirubin ≥2 mg/dl). RESULTS: Overall, 63% (10 of 16) of MOLE patients and 22% (30 of 136) of SOLE patients developed cholestasis after ≥14 days of therapy (P = 0.005). The latency to developing cholestasis was significantly shorter in MOLE patients compared with SOLE patients. CONCLUSION: In surgical neonates, MOLE may not prevent cholestasis and should not be considered hepatoprotective. Regardless of ILE source, all surgical neonates should be closely monitored for development of IFALD. To date, there is still no ILE able to prevent IFALD.

Fat digestion using RELiZORB in children with short bowel syndrome who are dependent on parenteral nutrition: Protocol for a 90-day, phase 3, open labeled study.

BACKGROUND: Short bowel syndrome (SBS) is a leading cause of intestinal failure resulting in parenteral nutrition (PN) dependence and nutritional deficiencies. Long-term PN use is associated with the development of sepsis and intestinal failure-associated liver disease. Achieving enteral autonomy is the optimal way to prevent these complications. In SBS, the decreased intestinal length, bile acid deficiency, and rapid transit time contribute to fat malabsorption and continued PN dependence. We propose the use of an immobilized lipase cartridge (ILC; RELiZORB) that connects in-line with enteral feed tubing sets and is designed to breakdown the majority of fats provided in enteral nutrition (EN). Preclinical studies have demonstrated both improved fat and fat-soluble vitamin absorption with ILC use in a porcine model of SBS. To evaluate the clinical applicability of these findings, we designed a phase 3, open labeled, single center, clinical trial to determine the safety, tolerability, and efficacy of the RELiZORB enzyme cartridge when used daily with EN for 90 days. METHODS: The patient population will include PN dependent children with SBS, aged 2-18 years. The primary outcome is the change in PN calories from baseline, assessed weekly throughout the study. Changes in growth Z-scores, 72-hour fecal fat and coefficient of fat absorption, plasma fatty acids and fat-soluble vitamins will also be evaluated. Assessment of change in continuous outcomes will be made using the area under the curve, expressed as a percent change relative to baseline, calculated over study day 7 to 90 (AUC7-90). The incidence of adverse events will be monitored and summarized by system organ class. DISCUSSION: If successful, RELiZORB may offer a safe alternative to reducing PN dependence and achieving enteral autonomy in pediatric intestinal failure. These results would be clinically significant given the clear association between long-term PN use and complications in SBS. TRIAL REGISTRATION: ClinicalTrials.gov NCT03530852; registered on May 21st, 2018, last update posted on September 14th, 2022.

Ethanol lock therapy increases mechanical catheter complications in a pediatric intestinal failure population: A retrospective cohort study.

BACKGROUND: Ethanol lock therapy (ELT) decreases central line-associated bloodstream infections; however, the effect on mechanical catheter complications is unclear. In recent years, ELT has become unavailable for many patients, often resulting in high-risk patients switching back to heparin locks. We investigated the impact of ELT on mechanical catheter complications during this period. METHODS: We performed a retrospective cohort study of the Boston Children's Hospital intestinal rehabilitation program from January 1, 2018, to December 31, 2020. Pediatric patients with a central venous catheter requiring parenteral support for 3 months were included. The primary outcome was the composite rate of mechanical catheter complications (repairs and replacements). RESULTS: The pediatric intestinal failure cohort consisted of 122 patients. Forty-four percent received ELT for the entirety of the study period, 29% used only heparin locks, and 27% used ELT and heparin locks at different periods. During ELT use, there was 1.65 times the risk of mechanical catheter complications (composite outcome of repairs and replacements) compared with heparin locks (adjusted incidence rate ratio [aIRR] = 1.65, 95% CI = 1.18-2.31). Current ELT use was associated with 2.3 times the risk of catheter repairs (aIRR = 2.30, 95% CI = 1.36-3.89) but no significant increase in catheter replacement risk (aIRR = 1.41, 95% CI = 0.91-2.20). CONCLUSION: In the largest pediatric intestinal failure cohort evaluated to date, the use of ELT, compared with heparin locks, increased the risk of mechanical catheter complications. Mechanical complications carry morbidity requiring urgent clinic or emergency department visits and additional procedures. The investigation of alternative lock solutions is warranted.

Absorption of an engineered medium-chain fatty acid analogue in two short bowel syndrome minipig models.

BACKGROUND: Enteral drug therapy is challenging in short bowel syndrome with intestinal failure (SBS-IF) because of unpredictable absorption. SEFA-6179 is an enterally administered medium-chain fatty acid analogue under development for intestinal failure-associated liver disease. We investigate the pharmacokinetics of two SEFA-6179 formulations in two large-animal models of SBS-IF, including a new pseudojejunostomy model. METHODS: Twenty Yucatan minipigs were obtained. Half underwent pre-resection pharmacokinetic study with single-dose SEFA-6179 administration. All minipigs then underwent 90% jejunoileal resection, with either a jejunoileal anastomosis or bypass of the intraperitoneal colon with anastomosis just proximal to the rectum (pseudojejunostomy). On postoperative day 3, a single-dose pharmacokinetic study was performed. RESULTS: Both SBS-IF models were well tolerated. Compared with the jejunoileal anastomosis minipigs, pseudojejunostomy minipigs had a more severe malabsorptive phenotype with weight loss by postoperative day 4 (+0.1 vs -0.9 kg, P = 0.03) and liquid diarrhea (Bristol 5 vs Bristol 7, P = 0.0007). Compared with pre-resection minipigs, both jejunoileal and pseudojejunostomy minipigs had lower total plasma exposure of SEFA-6179 measured by area under the curve (jejunoileal: 37% less, P = 0.049; pseudojejunostomy: 74% less, P = 0.0001). Peak plasma concentration was also lower in the pseudojejunostomy group compared with pre-resection (65% less, P = 0.04), but not lower in the jejunoileal group (P = 0.47). CONCLUSION: In two SBS-IF minipig models, SEFA-6179 had substantially decreased absorption compared with pre-resection minipigs. Dose optimization for different intestinal anatomy and function may be required. We describe a new SBS-IF pseudojejunostomy model that may improve the translation of preclinical research to patients with SBS-IF who have enterostomies.

A pneumonectomy model to study flow-induced pulmonary hypertension and compensatory lung growth.

In newborns, developmental disorders such as congenital diaphragmatic hernia (CDH) and specific types of congenital heart disease (CHD) can lead to defective alveolarization, pulmonary hypoplasia, and pulmonary arterial hypertension (PAH). Therapeutic options for these patients are limited, emphasizing the need for new animal models representative of disease conditions. In most adult mammals, compensatory lung growth (CLG) occurs after pneumonectomy; however, the underlying relationship between CLG and flow-induced pulmonary hypertension (PH) is not fully understood. We propose a murine model that involves the simultaneous removal of the left lung and right caval lobe (extended pneumonectomy), which results in reduced CLG and exacerbated reproducible PH. Extended pneumonectomy in mice is a promising animal model to study the cellular response and molecular mechanisms contributing to flow-induced PH, with the potential to identify new treatments for patients with CDH or PAH-CHD.