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Dive into the research topics where Samuel C. Schecter is active.

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Featured researches published by Samuel C. Schecter.


Journal of Pediatric Surgery | 2012

Long-term outcomes after fetal therapy for congenital high airway obstructive syndrome

Payam Saadai; Eric B. Jelin; Amar Nijagal; Samuel C. Schecter; Shinjiro Hirose; Tippi C. MacKenzie; Larry Rand; Ruth B. Goldstein; Jody A. Farrell; Michael R. Harrison; Hanmin Lee

BACKGROUND/PURPOSE Congenital high airway obstructive syndrome (CHAOS) is a rare and devastating condition that is uniformly fatal without fetal intervention. We sought to describe fetal treatment and long-term outcomes of CHAOS at a single referral center. METHODS The medical records of patients with fetal CHAOS evaluated at our center between 1993 and 2011 were reviewed. Maternal history, radiographic findings, antenatal management, and postnatal outcomes were compared. RESULTS Twelve fetuses with CHAOS were identified. Eleven had concomitant hydrops at diagnosis. Six were electively terminated, and 2 had intra- or peripartum demise. Four patients underwent fetal intervention. Two underwent delivery via ex utero intrapartum treatment (EXIT) procedure with tracheostomy placement only, and 2 underwent fetal bronchoscopy with attempted wire tracheoplasty followed by EXIT with tracheostomy at delivery. All 4 patients who underwent EXIT were alive at last follow-up. One patient was ventilator and tracheostomy free and feeding by mouth. CONCLUSION Long-term and tracheostomy-free survival is possible with appropriate fetal intervention even in the presence of hydrops. Fetal intervention earlier in pregnancy may improve long-term outcomes, but patient selection for intervention remains challenging. Magnetic resonance imaging may help select those patients for whom fetal intervention before EXIT delivery may be beneficial.


Journal of Pediatric Surgery | 2014

Antenatal maternally-administered phosphodiesterase type 5 inhibitors normalize eNOS expression in the fetal lamb model of congenital diaphragmatic hernia

Eveline H. Shue; Samuel C. Schecter; Wenhui Gong; Mozziyar Etemadi; Michael Johengen; Corey W. Iqbal; S. Christopher Derderian; Peter Oishi; Jeffrey R. Fineman; Doug Miniati

PURPOSE Pulmonary hypertension (pHTN), a main determinant of survival in congenital diaphragmatic hernia (CDH), results from in utero vascular remodeling. Phosphodiesterase type 5 (PDE5) inhibitors have never been used antenatally to treat pHTN. The purpose of this study is to determine if antenatal PDE5 inhibitors can prevent pHTN in the fetal lamb model of CDH. METHODS CDH was created in pregnant ewes. Postoperatively, pregnant ewes received oral placebo or tadalafil, a PDE5 inhibitor, until delivery. Near term gestation, lambs underwent resuscitations, and lung tissue was snap frozen for protein analysis. RESULTS Mean cGMP levels were 0.53±0.11 in placebo-treated fetal lambs and 1.73±0.21 in tadalafil-treated fetal lambs (p=0.002). Normalized expression of eNOS was 82%±12% in Normal-Placebo, 61%±5% in CDH-Placebo, 116%±6% in Normal-Tadalafil, and 86%±8% in CDH-Tadalafil lambs. Normalized expression of β-sGC was 105%±15% in Normal-Placebo, 82%±3% in CDH-Placebo, 158%±16% in Normal-Tadalafil, and 86%±8% in CDH-Tadalafil lambs. Endothelial NOS and β-sGC were significantly decreased in CDH (p=0.0007 and 0.01 for eNOS and β-sGC, respectively), and tadalafil significantly increased eNOS expression (p=0.0002). CONCLUSIONS PDE5 inhibitors can cross the placental barrier. β-sGC and eNOS are downregulated in fetal lambs with CDH. Antenatal PDE5 inhibitors normalize eNOS and may prevent in utero vascular remodeling in CDH.


JAMA Surgery | 2015

Morbidity and Mortality Associated With Elective or Emergency Paraesophageal Hernia Repair

Jennifer Kaplan; Samuel C. Schecter; Matthew Lin; Stanley J. Rogers; Jonathan T. Carter

PACIFIC COAST SURGICAL ASSOCIATION Morbidity and Mortality Associated With Elective or Emergency Paraesophageal Hernia Repair For decades, the standard of care for a paraesophageal hiatal hernia (PEH) was surgical repair after diagnosis, irrespective of symptoms. This standard of care was based on the reported high risk of acute gastric volvulus, strangulation, bleeding, or obstruction associated with untreated PEH and on the high mortality associated with emergency repair.1,2 A paradigm shift occurred in 2002, when Stylopoulos et al,3 using Markov analysis, found that watchful waiting was superior to elective repair for patients older than 65 years of age with a minimally symptomatic PEH. As a result, many patients with a PEH deferred surgery and opted for watchful waiting. A predictable consequence of watchful waiting has been an increase in the number of patients presenting with an acute PEH, sometimes with catastrophic outcomes.4 We characterized outcomes of emergency PEH repair in the modern era compared with elective repair using data from the American College of Surgeons National Surgical Quality Improvement Program. Methods | We reviewed all PEH repairs reported to the American College of Surgeons National Surgical Quality Improvement Program from 2005 to 2012. Inclusion criteria were an age of 18 years or older at the time of surgery, an International Classification of Diseases, Ninth Revision (ICD-9) primary diagnosis code of diaphragmatic hernia (ie, ICD-9 code 551.3, 552.3, or 553.3), and a primary Current Procedural Terminology code indicating repair, as described by Mungo et al.5 Demographic data, comorbidities, and preoperative laboratory values were reviewed. The primary outcome was 30-day mortality. Secondary outcomes were hospital length of stay and serious morbidity (defined as return to the operating room, cardiac complication, sepsis, shock, ventilation >48 hours, unplanned reintubation, or cerebrovascular accident or stroke). Because this research involves only deidentified patient information, it did not require institutional review board approval from the University of California, San Francisco. Predictors of serious morbidity and 30-day mortality were identified in univariate logistic regression. Multivariate predictors were identified using backward-stepwise logistic regression. Statistical significance was defined as P < .05.


Journal of Pediatric Surgery | 2011

Dynamic tracheal occlusion improves lung morphometrics and function in the fetal lamb model of congenital diaphragmatic hernia

Eric B. Jelin; Mozziyar Etemadi; Jose Luis Encinas; Samuel C. Schecter; Cheryl J. Chapin; Jianfeng Wu; Salvador Guevara-Gallardo; Amar Nijagal; Kelly D. Gonzales; William T. Ferrier; Shuvo Roy; Doug Miniati

BACKGROUND Congenital diaphragmatic hernia (CDH) is associated with significant neonatal morbidity and mortality. Although prenatal complete tracheal occlusion (cTO) causes hypoplastic CDH lungs to enlarge, improved lung function has not been demonstrated. Furthermore, cTO interferes with the dynamic pressure change and fluid flow associated with fetal breathing. PURPOSE The purpose of the study was to assess a novel dynamic tracheal occlusion (dTO) device that preserves pressure changes and fluid flow. METHODS In this pilot study, CDH was created in fetal lambs at 65 days of gestational age (GA). At 110 days GA, a cTO device (n = 3) or a dTO device (n = 4) was placed in the fetal trachea. At 135 days GA, lambs were delivered and resuscitated. Unoperated lamb co-twins (n = 5), sham thoracotomy lambs (n = 2), and untreated CDH lambs (n = 3) served as controls. RESULTS Tracheal opening pressure, lung volume, lung fluid total protein, and phospholipid were significantly higher in the cTO group than in the dTO and unoperated control groups. Maximal oxygenation and lung compliance were significantly lower in the cTO group when compared with the unoperated control and dTO groups. CONCLUSION Preliminary results suggest that in the fetal lamb CDH model, dTO restores normal lung morphometrics and function, whereas cTO leads to enlarged but less functional lungs.


Journal of Pediatric Surgery | 2013

Aberrant pulmonary lymphatic development in the nitrofen mouse model of congenital diaphragmatic hernia

Eveline H. Shue; Jianfeng Wu; Samuel C. Schecter; Doug Miniati

PURPOSE Many infants develop a postsurgical chylothorax after diaphragmatic hernia repair. The pathogenesis remains elusive but may be owing to dysfunctional lymphatic development. This study characterizes pulmonary lymphatic development in the nitrofen mouse model of CDH. METHODS CD1 pregnant mice were fed nitrofen/bisdiamine (N/B) or olive oil at E8.5. At E14.5 and E15.5, lung buds were categorized by phenotype: normal, N/B without CDH (N/B - CDH), or N/B with CDH (N/B+CDH). Anti-CD31 was used to localize all endothelial cells, while anti-LYVE-1 was used to identify lymphatic endothelial cells in lung buds using immunofluorescence. Differential protein expression of lymphatic-specific markers was analyzed. RESULTS Lymphatic endothelial cells localized to the mesenchyme surrounding the airway epithelium at E15.5. CD31 and LYVE-1 colocalization identified lymphatic endothelial cells. LYVE-1 expression was upregulated in N/B+CDH lung buds in comparison to N/B - CDH and normal lung buds by immunofluorescence. Western blotting shows that VEGF-D, LYVE-1, Prox-1, and VEGFR-3 expression was upregulated in N/B+CDH lung buds in comparison to N/B - CDH or control lung buds at E14.5. CONCLUSIONS Lung lymphatics are hyperplastic in N/B+CDH. Upregulation of lymphatic-specific genes suggests that lymphatic hyperplasia plays an important role in dysfunctional lung lymphatic development in the nitrofen mouse model of CDH.


Surgery for Obesity and Related Diseases | 2017

Expanded indications for bariatric surgery: should patients on chronic steroids be offered bariatric procedures?

Jennifer Kaplan; Samuel C. Schecter; Stanley J. Rogers; Matthew Lin; Andrew M. Posselt; Jonathan T. Carter

BACKGROUND Patients who take chronic corticosteroids are increasingly referred for bariatric surgery. Little is known about their clinical outcomes. OBJECTIVE Determine whether chronic steroid use is associated with increased morbidity and mortality after stapled bariatric procedures. SETTING American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. METHODS All patients who underwent laparoscopic sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass and were reported to the ACS-NSQIP from 2011 to 2013 were reviewed. Patients were grouped based on type of surgery and history of chronic steroid use. Primary outcome measures were mortality and serious morbidity in the first 30 days. Regression analyses were used to determine predictors of outcome. RESULTS Of 23,798 patients who underwent laparoscopic sleeve gastrectomy and 38,184 who underwent Roux-en-Y gastric bypass, 385 (1.6%) and 430 (1.1%), respectively, were on chronic steroids. Patients on chronic steroids had a 3.4 times increased likelihood of dying within 30 days (95% confidence interval 1.4-8.1, P = .007), and 2-fold increased odds of serious complications (95% confidence interval 1.2-2.3, P = .008), regardless of surgery type. In multivariate regression, steroid usage remained an independent predictor of mortality and serious complications. CONCLUSION In a large, nationally representative patient database, steroid use independently predicted mortality and serious postoperative complications after stapled bariatric procedures. Surgeons should be cautious about offering stapled bariatric procedures to patients on chronic steroids.


Journal of Pediatric Surgery | 2013

Hepatic portocholecystostomy for biliary atresia: A 25-year follow-up and review

Samuel C. Schecter; Jesse Courtier; Soo-Jin Cho; Payam Saadai; Shinjiro Hirose; Tippi C. MacKenzie; Doug Miniati

We report the successful salvage of a patients native liver 25 years after hepatic portocholecystostomy for biliary atresia. Our case demonstrates the effectiveness of biliary specific, high-resolution CT imaging in the diagnosis of, and operative planning for complex cases of biliary obstruction. We also report the longest-term pathologic follow-up of biliary atresia after hepatic portocholecystostomy. Life-long follow-up of patients with biliary atresia is important to prevent life-threatening complications of biliary stasis/obstruction.


international conference of the ieee engineering in medicine and biology society | 2012

Implantable Ultralow Pulmonary Pressure Monitoring System for Fetal Surgery

Mozziyar Etemadi; James A. Heller; Samuel C. Schecter; Eveline H. Shue; Douglas N. Miniati; Shuvo Roy

Congenital pulmonary hypoplasia is a devastating condition affecting fetal and newborn pulmonary physiology, resulting in great morbidity and mortality. The fetal lung develops in a fluid-filled environment. In this paper, we describe a novel, implantable pressure sensing and recording device which we use to study the pressures present in the fetal pulmonary tree throughout gestation. The system achieves 0.18 cm H 2O resolution and can record for 21 days continuously at 256 Hz. Sample tracings of in vivo fetal lamb recordings are shown.


Archive | 2011

Amputation in Combat Trauma

Nikolaj Wolfson; Samuel C. Schecter

Despite the advances of modern orthopedic trauma techniques, the amputation rate for injured victims of modern warfare is on the rise. Increased devastation from high-velocity missiles and the prevalence of high-energy explosives in combat are directly responsible for the rise in extremity injuries. The globalization of disaster response has placed military surgeons at the forefront of the acute care provided to those victims of natural disasters. The high volume of extremity injuries encountered in these extreme conditions proves the necessity for surgeons to understand and perform amputation.


Journal of Visualized Experiments | 2011

Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas

Eric B. Jelin; Samuel C. Schecter; Kelly D. Gonzales; Shinjiro Hirose; Hanmin Lee; Geoffrey A. Machin; Larry Rand; Vickie A. Feldstein

Monochorionic (MC) twin pregnancies are associated with significantly higher morbidity and mortality rates than dichorionic twins. Approximately 50% of MC twin pregnancies develop complications arising from the shared placenta and associated vascular connections. Severe twin-to-twin syndrome (TTTS) is reported to account for approximately 20% of these complications. Inter-twin vascular connections occur in almost all MC placentas and are related to the prognosis and outcome of these high-risk twin pregnancies. The number, size and type of connections have been implicated in the development of TTTS and other MC twin conditions. Three types of inter-twin vascular connections occur: 1) artery to vein connections (AVs) in which a branch artery carrying deoxygenated blood from one twin courses along the fetal surface of the placenta and dives into a placental cotyledon. Blood flows via a deep intraparenchymal capillary network into a draining vein that emerges at the fetal surface of the placenta and brings oxygenated blood toward the other twin. There is unidirectional flow from the twin supplying the afferent artery toward the twin receiving the efferent vein; 2) artery to artery connections (AAs) in which a branch artery from each twin meets directly on the superficial placental surface resulting in a vessel with pulsatile bidirectional flow, and 3) vein to vein connections (VVs) in which a branch vein from each twin meets directly on the superficial placental surface allowing low pressure bidirectional flow. In utero obstetric sonography with targeted Doppler interrogation has been used to identify the presence of AV and AA connections. Prenatally detected AAs that have been confirmed by postnatal placental injection studies have been shown to be associated with an improved prognosis for both twins. Furthermore, fetoscopic laser ablation of inter-twin vascular connections on the fetal surface of the shared placenta is now the preferred treatment for early, severe TTTS. Postnatal placental injection studies provide a valuable method to confirm the accuracy of prenatal Doppler ultrasound findings and the efficacy of fetal laser therapy. Using colored dyes separately hand-injected into the arterial and venous circulations of each twin, the technique highlights and delineates AVs, AAs, and VVs. This definitive demonstration of MC placental vascular anatomy may then be correlated with Doppler ultrasound findings and neonatal outcome to enhance our understanding of the pathophysiology of MC twinning and its sequelae. Here we demonstrate our placental injection technique.

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Doug Miniati

University of California

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Eric B. Jelin

University of California

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Jianfeng Wu

University of California

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Matthew Lin

University of California

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