Is fecal diversion necessary during ileal pouch creation after initial subtotal colectomy in pediatric ulcerative colitis?

BACKGROUND: Pediatric patients with medically refractory ulcerative colitis (UC) often undergo an initial subtotal colectomy end ileostomy (STC-I). The role of fecal diversion in the subsequent completion proctectomy/ileal-pouch anal anastomosis (CP-IPAA) remains controversial. METHODS: A multi-institutional retrospective review was performed of pediatric UC patients who underwent an STC-I followed by CP-IPAA from 2008 to 2016. 37 patients were included [diverted (n = 20), undiverted (n = 17)]. RESULTS: Children who underwent undiverted CP-IPAA had a longer length of stay (days) compared to the diverted group (9, 6.5-13 vs. 6, 5-6, p = 0.002). The 30-day complication rate was significantly higher in the undiverted group (p = 0.003) although the difference in anastomotic leak, readmission rate, unplanned computer tomography use, and reoperation was not statistically significant. Three patients with undiverted CP-IPAA required additional surgery in the perioperative period for fecal diversion. The mean long-term follow-up was 25.68 ± 21.56 months. There were no significant differences in functional pouch outcomes. CONCLUSIONS: Patients who underwent an undiverted CP-IPAA after initial STC-I had significantly more complications in the immediate postoperative period compared to diverted patients, although this did not translate into long-term differences in functional outcomes. Questions remain regarding careful patient selection and counseling for undiverted pouches in the pediatric UC population.

Manufacture and preparation of human placenta-derived mesenchymal stromal cells for local tissue delivery.

BACKGROUND: In this study we describe the development of a Current Good Manufacturing Practice (CGMP)-compliant process to isolate, expand and bank placenta-derived mesenchymal stromal cells (PMSCs) for use as stem cell therapy. We characterize the viability, proliferation and neuroprotective secretory profile of PMSCs seeded on clinical-grade porcine small intestine submucosa extracellular matrix (SIS-ECM; Cook Biotech). METHODS: PMSCs were isolated from early gestation placenta chorionic villus tissue via explant culture. Cells were expanded, banked and screened. Purity and expression of markers of pluripotency were determined using flow cytometry. Optimal loading density and viability of PMSCs on SIS-ECM were determined using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) cell proliferation and fluorescent live/dead assays, respectively. Growth factors secretion was analyzed using enzyme-linked immunosorbent assays (ELISA). RESULTS: PMSCs were rapidly expanded and banked. Viable Master and Working Cell Banks were stable with minimal decrease in viability at 6 months. All PMSCs were sterile, free from Mycoplasma species, karyotypically normal and had low endotoxin levels. PMSCs were homogeneous by immunophenotyping and expressed little to no pluripotency markers. Optimal loading density on SIS-ECM was 3-5 × 105 cells/cm2, and seeded cells were >95% viable. Neurotrophic factor secretion was detectable from PMSCs seeded on plastic and SIS-ECM with variability between donor lots. DISCUSSION: PMSCs from early gestation placental tissues can be rapidly expanded and banked in stable, viable cell banks that are free from contaminating agents, genetically normal and pure. PMSC delivery can be accomplished by using SIS-ECM, which maintains cell viability and protein secretion. Future work in vivo is necessary to optimize cell seeding and transplantation to maximize therapeutic capabilities.

Outcomes of robot-assisted versus laparoscopic repair of small-sized ventral hernias.

INTRODUCTION: The aim of the study is to investigate the outcomes of the da Vinci robot-assisted laparoscopic hernia repair of small-sized ventral hernias with circumferential suturing of the mesh compared to the traditional laparoscopic repair with trans-fascial suturing. METHODS: A retrospective review was conducted of all robot-assisted umbilical, epigastric and incisional hernia repairs performed at our institution between 2013 and 2015 compared to laparoscopic umbilical or epigastric hernia repairs. Patient characteristics, operative details and postoperative complications were collected and analyzed using univariate analysis. Three primary minimally invasive fellowship trained surgeons performed all of the procedures included in the analysis. RESULTS: 72 patients were identified during the study period. 39 patients underwent robot- assisted repair (21 umbilical, 14 epigastric, 4 incisional), and 33 patients laparoscopic repair (27 umbilical, 6 epigastric). Seven had recurrent hernias (robot: 4, laparoscopic: 3). There were no significant differences in preoperative characteristics between the two groups. Average operative time was 156 min for robot-assisted repair and 65 min for laparoscopic repair (p < 0.0001). The average defect size was significantly larger for the robot group [3.07 cm (1-9 cm)] than that for the laparoscopic group [2.02 cm (0.5-5 cm)] (p < 0.0001), although there was no significant difference in the average size of mesh used (13 vs. 13 cm). There was no difference in patients requiring postoperative admission or length of stay between the two groups. The mean duration of follow-up was 47 days. There was no difference in complication rate during this time, and no recurrences were reported. CONCLUSION: There are no significant differences in terms of safety and early efficacy when comparing small-sized ventral hernias repaired using the robot-assisted technique versus the standard laparoscopic repair.

New directions in fetal surgery for myelomeningocele.

The treatment of children with myelomeningocele (MMC) has improved over time, from supportive management to early postnatal closure to prenatal repair of the defect. The Management of Myelomeningocele Study (MOMS) showed that prenatal repair of MMC resulted in improved neurological outcomes compared to postnatal closure. Follow-up studies showed that prenatal repair was, as with any other fetal intervention, associated with higher rates of obstetrical complications. There was no significant difference in urological outcomes. Long-term follow-up of ambulatory status, executive functioning, and urological outcomes is needed to determine the durable effects of fetal MMC repair on mobility, functional independence, and the prevalence of renal insufficiency in patients with MMC who survive to adulthood. The future of fetal MMC repair consists of developing strategies to reduce maternal morbidity and improve infant outcomes. Fetoscopic MMC repair has been suggested as an alternative to open repair that may reduce obstetrical complications and the need for cesarean delivery in subsequent pregnancies. Translational research using mesenchymal stromal cells to augment fetal repair of ovine MMC has shown improvement in motor function.

Unusual case of delayed congenital diaphragmatic hernia in Loeys-Dietz syndrome: a case report.

Congenital diaphragmatic hernias rarely present after 2 months of age and are typically diagnosed in the perinatal period. Moderate to severe diaphragmatic hernias present with respiratory symptoms, while late-onset hernias have a more varied presentation, depending on the age and content of the hernia. Very rarely, such hernias are found on incidental imaging, in which surgical repair is frequently recommended. A young girl with Loeys-Dietz syndrome and prior abdominal surgeries presents with 1-year history of increasingly severe, intermittent, abdominal and left shoulder pain. Prior imaging incidentally revealed a left diaphragmatic hernia with omentum protruding into the thoracic cavity. This was managed expectantly due to her other medical and surgical issues. Serial imaging revealed that the herniated omentum was increasing in size and symptoms began to develop. An uncomplicated primary thoracoscopic repair was performed. We report the first case of a congenital diaphragmatic hernia in a patient with Loeys-Dietz syndrome.

Extracorporeal cardiopulmonary resuscitation for the treatment of amlodipine overdose in a pediatric patient.

We present the case of a 16-year-old female with systemic lupus erythematosus who presented with shock of unclear etiology, refractory to fluid resuscitation and triple vasopressors. She suffered pulseless electrical activity and underwent cannulation onto veno-arterial extracorporeal membrane oxygenation (ECMO). After cannulation, it was discovered she had intentionally overdosed on her home medication, amlodipine, a calcium channel blocker (CCB). She was supported on ECMO, treated with IV calcium and insulin, and was able to be weaned off ECMO after 4 days. She developed oligoanuric acute kidney injury, treated with continuous renal replacement therapy followed by intermittent hemodialysis. At discharge, she was neurologically intact and did not require dialysis. Herein, we review the treatment of CCB overdose, review the literature on the use of ECMO in refractory shock due to cardiovascular medication overdose, and highlight the utility of ECMO in pediatric refractory shock and/or cardiac arrest of unclear etiology.

High density placental mesenchymal stromal cells provide neuronal preservation and improve motor function following in utero treatment of ovine myelomeningocele.

PURPOSE: The purpose of this study was to determine whether seeding density of placental mesenchymal stromal cells (PMSCs) on extracellular matrix (ECM) during in utero repair of myelomeningocele (MMC) affects motor function and neuronal preservation in the ovine model. METHODS: MMC defects were surgically created in 33 fetuses and repaired following randomization into four treatment groups: ECM only (n = 10), PMSC-ECM (42 K cells/cm2) (n = 8), PMSC-ECM (167 K cells/cm2) (n = 7), or PMSC-ECM (250-300 K cells/cm2) (n = 8). Motor function was evaluated using the Sheep Locomotor Rating Scale (SLR). Serial sections of the lumbar spinal cord were analyzed by measuring their cross-sectional areas which were then normalized to normal lambs. Large neurons (LN, diameter 30-70 µm) were counted manually and density calculated per mm2 gray matter. RESULTS: Lambs treated with PMSCs at any density had a higher median SLR score (15 [IQR 13.5-15]) than ECM alone (6.5 [IQR 4-12.75], p = 0.036). Cross-sectional areas of spinal cord and gray matter were highest in the PMSC-ECM (167 K/cm2) group (p = 0.002 and 0.006, respectively). LN density was highest in the greatest density PMSC-ECM (250-300 K/cm2) group (p = 0.045) which positively correlated with SLR score (r = 0.807, p < 0.0001). CONCLUSIONS: Fetal repair of myelomeningocele with high density PMSC-ECM resulted in increased large neuron density, which strongly correlated with improved motor function. TYPE OF STUDY: Basic science. LEVEL OF EVIDENCE: N/A.

Lessons from the Barn to the Operating Suite: A Comprehensive Review of Animal Models for Fetal Surgery.

The International Fetal Medicine and Surgery Society was created in 1982 and proposed guidelines for fetal interventions that required demonstrations of the safety and feasibility of intended interventions in animal models prior to application in humans. Because of their short gestation and low cost, small animal models are useful in early investigation of fetal strategies. However, owing to the anatomic and physiologic differences between small animals and humans, repeated studies in large animal models are usually needed to facilitate translation to humans. Ovine (sheep) models have been used the most extensively to study the pathophysiology of congenital abnormalities and to develop techniques for fetal interventions. However, nonhuman primates have uterine and placental structures that most closely resemble those of humans. Thus, the nonhuman primate is the ideal model to develop surgical and anesthetic techniques that minimize obstetrical complications.

Subcutaneous local anesthetic infusion could eliminate use of epidural analgesia after the Nuss procedure.

AIM: To compare outcomes of continuous subcutaneous infusion of local anesthetic and epidural analgesia following the Nuss procedure. PATIENTS & METHODS: A retrospective chart review compared patients managed with subcutaneous local anesthetic infusion (n = 12) versus thoracic epidural (n = 19) following the Nuss procedure from March 2013 to June 2015. RESULTS: There was no difference in hospital length of stay or days on intravenous narcotics. Epidural catheter placement prolonged operating room time (146.58 ± 28.30 vs 121.42 ± 21.98 min, p = 0.01). Average pain scores were slightly higher in the subcutaneous infusion group (3.72 ± 1.62 vs 2.35 ± 0.95, p = 0.02), but of negligible clinical significance. CONCLUSION: Continuous subcutaneous infusion of local anesthetic could eliminate the need for thoracic epidural for pain management after the Nuss procedure.

Effect of 2-octylcyanoacrylate on placenta derived mesenchymal stromal cells on extracellular matrix.

PURPOSE: Determine the effect of 2-octylcyanoacrylate on placenta derived mesenchymal stromal cells (PMSCs) seeded onto extracellular matrix (ECM) in order to assess its biocompatibility as a potential adhesive for in-vivo fetal cell delivery. METHODS: PMSCs isolated from chorionic villus tissue were seeded onto ECM. A MTS proliferation assay assessed cellular metabolic activity at various time points in PMSC-ECM with direct, indirect, and no glue contact. Conditioned media collected prior to and 24 hours after glue exposure was analyzed for secretion of human brain-derived neurotrophic factor, hepatocyte growth factor, and vascular endothelial growth factor. RESULTS: Direct and indirect contact with 2-octylcyanoacrylate results in progressively decreased cellular metabolic activity over 24 hours compared to no glue controls. Cells with direct contact are less metabolically active than cells with indirect contact. 24 hours of glue exposure resulted in suppression of growth factor secretion that is near complete with direct contact. DISCUSSION: Exposure to 2-octylcyanoacrylate results in decreased metabolic activity and decreased measurable secretion of growth factors by PMSCs seeded onto ECM. Thus, the application of 2-octylcyanoacrylate glue should be limited when working with cell-engineered scaffolds as its inhibitory effects on cell growth and secretory function can limit the therapeutic potential of cell-based interventions.

Fetal surgical repair with placenta-derived mesenchymal stromal cell engineered patch in a rodent model of myelomeningocele.

PURPOSE: The purpose of this study is to determine the feasibility of fetal surgical repair of myelomeningocele (MMC) in a rodent model using human placental mesenchymal stromal cells (PMSCs) seeded onto extracellular matrix (ECM) and to characterize the resulting changes in spinal cord tissue. METHODS: Fetal rodents with retinoic acid (RA) induced MMC underwent surgical repair of the MMC defect using an ECM patch on embryonic age (EA) 19 and were collected via caesarean section on EA 21. Various seeding densities of PMSC-ECM and ECM only controls were evaluated. Cross-sectional compression (width/height) and apoptotic cell density of the lumbosacral spinal cord were analyzed. RESULTS: 67 dams treated with 40mg/kg of RA resulted in 352 pups with MMC defects. 121 pups underwent MMC repair, and 105 (86.8%) survived to term. Unrepaired MMC pups had significantly greater cord compression and apoptotic cell density compared to normal non-MMC pups. Pups treated with PMSC-ECM had significantly less cord compression and demonstrated a trend towards decreased apoptotic cell density compared to pups treated with ECM only. CONCLUSION: Surgical repair of MMC with a PMSC-seeded ECM disc is feasible with a postoperative survival rate of 86.8%. Fetal rodents repaired with PMSC-ECM have significantly less cord deformity and decreased histological evidence of apoptosis compared to ECM only controls.

Isolation of myogenic progenitor cell population from human placenta: A pilot study.

PURPOSE: The purpose of this study was to demonstrate a method of isolating myogenic progenitor cells from human placenta chorionic villi and to confirm the myogenic characteristics of the isolated cells. METHODS: Cells were isolated from chorionic villi of a second trimester male placenta via a combined enzymatic digestion and explant culture. A morphologically distinct subpopulation of elongated and multinucleated cells was identified. This subpopulation was manually passaged from the explant culture, expanded, and analyzed by fluorescence in situ hybridization (FISH) assay, immunocytochemistry, and flow cytometry. Myogenic characteristics including alignment and fusion were tested by growing these cells on aligned polylactic acid microfibrous scaffold in a fusion media composed of 2% horse serum in Dulbecco's modified Eagle medium/high glucose. RESULTS: The expanded subpopulation was uniformly positive for integrin α-7. Presence of Y-chromosome by FISH analysis confirmed chorionic villus origin rather than maternal cell contamination. Isolated cells grew, aligned, and fused on the microfibrous scaffold, and they expressed myogenin, desmin, and MHC confirming their myogenic identity. CONCLUSION: Myogenic progenitor cells can be isolated from human chorionic villi. This opens the possibility for translational and clinical applications using autologous myogenic cells for possible engraftment in treatment of chest and abdominal wall defects.

Placental mesenchymal stromal cells seeded on clinical grade extracellular matrix improve ambulation in ovine myelomeningocele.

PURPOSE: The purpose of this study was to investigate the effects of placental mesenchymal stromal cells (PMSCs) seeded on a clinical grade porcine small intestinal submucosa (SIS)-derived extracellular matrix (ECM) on hindlimb motor function in an ovine fetal repair model of myelomeningocele (MMC). METHODS: MMC defects were surgically created in 21 fetuses at median gestational age 78 (range 76-83) days. Fetuses were randomly assigned to repair 25days later with ECM only or PMSC-ECM. Surviving fetuses were delivered at term. Motor function was evaluated using the Sheep Locomotor Rating (SLR) scale (0-15). Histologic analysis of the spinal cord (SC) was completed. RESULTS: Fetal viability was 71%. 5 of 8 (63%) lambs repaired with PMSC-ECM ambulated independently versus only 1 of 6 (17%) repaired with ECM only (p=0.04, χ2 test). SLR scores and large neuron densities were higher in the PMSC-ECM group. The cross-sectional areas of the SC and the gray matter were equally preserved. CONCLUSIONS: Fetal repair of MMC with PMSCs seeded on SIS-ECM improves hindlimb motor function in lambs. Using ECM helps to preserve the architecture of the SC, but adding PMSCs improves the lamb's ability to walk and increases large neuron density. Clinical studies are needed to show benefits in humans. LEVELS OF EVIDENCE/TYPE OF STUDY: Basic Science.

Intercostal nerve cryoablation versus thoracic epidural catheters for postoperative analgesia following pectus excavatum repair: Preliminary outcomes in twenty-six cryoablation patients.

BACKGROUND: Multimodal pain management strategies are used for analgesia following pectus excavatum repair. However, the optimal regimen has not been identified. We describe our early experience with intercostal cryoablation for pain management in children undergoing the Nuss procedure and compare early cryoablation outcomes to our prior outcomes using thoracic epidural analgesia. METHODS: A multi-institutional, retrospective review of fifty-two patients undergoing Nuss bar placement with either intercostal cryoablation (n=26) or thoracic epidural analgesia (n=26) from March 2013 to January 2016 was conducted. The primary outcome was hospital length of stay. Secondary outcomes included telemetry unit monitoring time, total intravenous narcotic use, duration of intravenous narcotic use, and postoperative complications. RESULTS: Patients who underwent intercostal cryoablation had a significant reduction in the mean hospital length of stay, time in a monitored telemetry bed, total use of intravenous narcotics, and the duration of intravenous narcotic administration when compared to thoracic epidural patients. Cryoablation patients had a slightly higher rate of postoperative complications. CONCLUSION: Intercostal cryoablation is a promising technique for postoperative pain management in children undergoing repair of pectus excavatum. This therapy results in reduced time to hospital discharge, decreased intravenous narcotic utilization, and has eliminated epidurals from our practice. LEVEL OF EVIDENCE: Retrospective study - level III.