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1.
J Surg Res ; 277: A25-A35, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35307162

RESUMO

Emotional regulation is increasingly gaining acceptance as a means to improve well-being, performance, and leadership across high-stakes professions, representing innovation in thinking within the field of surgical education. As one part of a broader cognitive skill set that can be trained and honed, emotional regulation has a strong evidence base in high-stress, high-performance fields. Nevertheless, even as Program Directors and surgical educators have become increasingly aware of this data, with emerging evidence in the surgical education literature supporting efficacy, hurdles to sustainable implementation exist. In this white paper, we present evidence supporting the value of emotional regulation training in surgery and share case studies in order to illustrate practical steps for the development, adaptation, and implementation of emotional regulation curricula in three key developmental contexts: basic cognitive skills training, technical skills acquisition and performance, and preparation for independence. We focus on the practical aspects of each case to elucidate the challenges and opportunities of introducing and adopting a curricular innovation into surgical education. We propose an integrated curriculum consisting of all three applied contexts for emotional regulation skills and advocate for the dissemination of such a longitudinal curriculum on a national level.


Assuntos
Regulação Emocional , Liderança , Competência Clínica , Currículo
2.
J Surg Res ; 206(1): 62-66, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27916376

RESUMO

BACKGROUND: The ability to predict whether a child has complicated appendicitis at initial presentation may influence clinical management. However, whether complicated appendicitis is associated with prehospital or inhospital factors is not clear. We also investigate whether hyponatremia may be a novel prehospital factor associated with complicated appendicitis. MATERIALS AND METHODS: A retrospective review of all pediatric patients (≤12 y) with appendicitis treated with appendectomy from 2000 to 2013 was performed. The main outcome measure was intraoperative confirmation of gangrenous or perforated appendicitis. A multivariable analysis was performed, and the main predictors of interest were age <5 y, symptom duration >24 h, leukocytosis (white blood cell count >12 × 103/mL), hyponatremia (sodium ≤135 mEq/L), and time from admission to appendectomy. RESULTS: Of 392 patients, 179 (46%) had complicated appendicitis at the time of operation. Univariate analysis demonstrated that patients with complicated appendicitis were younger, had a longer duration of symptoms, higher white blood cell count, and lower sodium levels than patients with noncomplicated appendicitis. Multivariable analysis confirmed that symptom duration >24 h (odds ratio [OR] = 5.5, 95% confidence interval [CI] = 3.5-8.9, P < 0.01), hyponatremia (OR = 3.1, 95% CI = 2.0-4.9, P < 0.01), age <5 y (OR = 2.3, 95% CI = 1.3-4.0, P < 0.01), and leukocytosis (OR = 1.9, 95% CI = 1.0-3.5, P = 0.04) were independent predictors of complicated appendicitis. Increased time from admission to appendectomy was not a predictor of complicated appendicitis (OR = 0.8, 95% CI = 0.5-1.2, P = 0.2). CONCLUSIONS: Prehospital factors can predict complicated appendicitis in children with suspected appendicitis. Hyponatremia is a novel marker associated with complicated appendicitis. Delaying appendectomy does not increase the risk of complicated appendicitis once intravenous antibiotics are administered. This information may help guide resource/personnel allocation, timing of appendectomy, and decision for nonoperative management of appendicitis in children.


Assuntos
Apendicite/patologia , Apendicectomia , Apendicite/complicações , Apendicite/diagnóstico , Apendicite/cirurgia , Criança , Pré-Escolar , Feminino , Gangrena , Humanos , Hiponatremia/complicações , Masculino , Análise Multivariada , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
3.
J Surg Res ; 192(1): 27-33, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25015748

RESUMO

BACKGROUND: Enteric neuromuscular disease is a characteristic of several disease states, including Hirschsprung disease, esophageal achalasia, Chagas disease, and gastroparesis. Medical therapy for these conditions is limited, and surgical intervention may incur significant morbidity. Alternatively, transplantation of neural progenitor cells may regenerate enteric ganglia. Existing aganglionosis model systems are limited by swift animal demise or by spontaneous regeneration of native ganglia. We propose a novel protocol to induce permanent aganglionosis in a segment of rat jejunum, which may serve as an experimental transplantation target for cellular therapy. MATERIALS AND METHODS: This protocol was performed in 17 adult female Sprague-Dawley rats. A laparotomy was performed and a 1-cm segment of jejunum was isolated from continuity. Among 14 rats, the isolated segments were treated with benzalkonium chloride (BAC) for 20 min to induce aganglionosis. Jejunal segment isolation was performed without BAC treatment in three rats. The animals were euthanized at posttreatment days 21-166. Muscle layer diameter was compared among normal, isolated, and BAC-treated isolated jejunal segments. The presence of jejunal ganglia was documented by immunohistochemical staining (IHC) for beta-III tubulin (TUJ1) and S100, markers of neuronal and glial cell lineages, respectively. RESULTS: Ganglia were identified by IHC in normal and isolated jejunal segments. Isolated segments had significantly hypertrophied smooth muscle layers compared with normal jejunum (diameter 343 ± 53 µm versus 211 ± 37 µm, P < 0.0001). BAC-treated jejunal segments had no IHC evidence of ganglionic structures. Aganglionosis was persistent in all specimens up to 166 days after treatment. CONCLUSIONS: The exclusion of a jejunal segment from continuity and concurrent treatment with BAC results in an effective, reproducible, and permanent model of aganglionosis. Muscular hypertrophy and aganglionosis in the isolated jejunal segment make it an ideal recipient site for transplantation of neuroglial precursor cells.


Assuntos
Modelos Animais de Doenças , Sistema Nervoso Entérico/citologia , Doença de Hirschsprung/terapia , Células-Tronco Neurais/transplante , Ratos Sprague-Dawley , Transplante de Células-Tronco/métodos , Animais , Jejunostomia/métodos , Jejuno/inervação , Jejuno/cirurgia , Ratos
4.
J Pediatr Surg ; : 161643, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39261188

RESUMO

INTRODUCTION: Non-operative management of uncomplicated appendicitis in children is a safe alternative to laparoscopic appendectomy. The purpose of this study is to determine the feasibility of nonoperative outpatient management of uncomplicated appendicitis in pediatric patients. METHODS: A standardized pathway for non-operative outpatient management of uncomplicated appendicitis in children (NOMA-C) was implemented in a university pediatric surgery practice starting October 2021. Those who met criteria would be considered for discharge from the emergency department (ED) with oral antibiotics and close followup over the following year. A quality improvement project started concurrently to monitor patients for recurrent symptoms of appendicitis. RESULTS: A total of 121 patients were diagnosed with acute appendicitis during the study period (October 2021 to April 2023). Forty-five children (38%) met criteria for the NOMA-C protocol, and 11 patients/families chose appendectomy. Of the 34 patients who pursued nonoperative management, 14 patients were admitted to the hospital and 20 patients were discharged from the ED. Total time in the ED/hospital was significantly shorter for patients discharged from the ED (7 hours versus 23 hours; p<0.001). At one year follow up only 4 (12%) had undergone appendectomy. There were no adverse events for patients who underwent nonoperative management. CONCLUSION: A protocol offering non-operative management of appendicitis with an option for outpatient management was feasible and safe. Outpatient management was associated with shorter ED/hospital stays than those admitted. Future studies should evaluate whether this protocol can be adopted by EDs without pediatric surgery services to avoid the need for transfer.

5.
J Am Coll Surg ; 239(3): 309-316, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38577986

RESUMO

Nationwide abortion restrictions resulting from the Dobbs v Jackson Women's Health Organization (2022) decision have generated confusion and uncertainty among healthcare professionals, with concerns for liability impacting clinical decision-making and outcomes. The impact on pediatric surgery can be seen in prenatal counseling for fetal anomaly cases, counseling for fetal intervention, and recommendations for pregnant children and adolescents who seek termination. It is essential that all physicians and healthcare team members understand the legal implications on their clinical practices, engage with resources and organizations that can help navigate these circumstances, and consider advocating for patients and themselves. Pediatric surgeons must consider the impact of these changing laws on their ability to provide comprehensive and ethical care and counseling to all patients.


Assuntos
Cirurgiões , Humanos , Feminino , Gravidez , Estados Unidos , Cirurgiões/psicologia , Saúde Reprodutiva , Aborto Legal/legislação & jurisprudência , Aborto Legal/ética , Tomada de Decisão Clínica/ética , Aborto Induzido/legislação & jurisprudência , Aborto Induzido/ética
6.
J Pediatr Surg ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39117536

RESUMO

BACKGROUND: The Nuss procedure for pectus excavatum is associated with prolonged hospitalizations due to pain. We evaluated implementation of intercostal nerve cryoablation and enhanced recovery after surgery (ERAS) protocols on outcomes of Nuss procedures performed over six years at a single institution. METHODS: This retrospective cohort study included patients who underwent Nuss procedure from 10/2017 to 09/2023. Patients received epidurals prior to 06/2019, cryoablation from 06/2019 to 07/2021, and ERAS with cryoablation and intraoperative methadone administration after 07/2021. We used multivariable linear regression to evaluate length of stay (LOS), inpatient morphine milligram equivalents (MMEs), and discharge opioids. We assessed the balancing measures of operative time, postoperative pain scores, and complications. RESULTS: We identified 62 patients; 15 who received epidurals, 18 cryoablation, and 29 cryoablation with ERAS. Cryoablation was associated with a 62.3% (p < 0.001) decrease in length of stay, an 86.6% (p < 0.001) decrease in inpatient MMEs, and a 72.9% (p < 0.001) decrease in discharge opioids. Cryoablation was additionally associated with 24.5% (p = 0.02) longer operative times and 46.4% (p = 0.04) higher postoperative day one pain scores. Subsequent implementation of an ERAS protocol was associated with a further 82.8% (p = 0.04) decrease in discharge opioids and a 25.0% (p = 0.04) decrease in postoperative day one pain scores. CONCLUSIONS: Over six years of quality improvement efforts, we found the implementation of cryoablation and ERAS protocols to be associated with a significant decrease in length of stay and opioid exposures. Protocolized pain management and cryoablation may work synergistically to improve outcomes without compromising patient experience. LEVEL OF EVIDENCE: Level III - Retrospective comparative study.

7.
J Pediatr Surg ; 58(1): 89-93, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36280466

RESUMO

PURPOSE: The purpose of the study is to examine the long-term safety of an endoluminal bowel lengthening device prior to its use in the first human trial. In addition, device performance and natural passage will be evaluated. METHODS: Endoluminal lengthening springs were surgically placed into the jejunum of Yucatan minipigs using the Eclipse XL1 device. A matching internal control segment of jejunum was marked at the time of operation. Weekly weights and fluoroscopic studies were obtained to evaluate spring deployment and position until devices passed. Animals were euthanized at 28, 60, 90, and 180 days. At necropsy, length measurements were recorded, and histopathologic analysis was performed. RESULTS: There were no bowel obstructions or overt perforations attributable to the device. All surviving animals gained weight and were clinically thriving. All devices passed out of the rectum by 180 days. Bowel lengthening was seen in all experimental segments, and minimal fibrosis was observed by 180 days. CONCLUSION: Jejunal lengthening persisted after device had passed through the intestinal tract after 180 days. Early histopathologic changes of the jejunum during distraction enterogenesis normalized over time.


Assuntos
Síndrome do Intestino Curto , Dispositivos para Expansão de Tecidos , Animais , Jejuno/cirurgia , Reto/cirurgia , Síndrome do Intestino Curto/cirurgia , Porco Miniatura , Dispositivos para Expansão de Tecidos/efeitos adversos
8.
Clin Pediatr (Phila) ; 56(3): 226-230, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27378723

RESUMO

Appendicitis is one of the most common diagnoses in children and is frequently the focus of alleged malpractice. Causes for medical malpractice claims and outcomes of disputes in pediatric patients with appendicitis are currently unknown. A retrospective database review of all medical malpractice claims concerning the diagnosis of appendicitis from 1984 to 2013 in pediatric patients was performed. Alleged claims, causes of malpractice, and outcomes were recorded and analyzed. Of the 203 included cases, failure or delays in diagnosing appendicitis are the most common causes of malpractice lawsuits and account for the majority of the largest payments to plaintiffs outcomes. Cases that ultimately went to trial resulted in defense verdicts in 67.5%. Mortality occurred in 19.9% of included cases. Timely diagnosis of appendicitis in children should be the focus of physicians across all specialties to improve patient safety and potentially reduce medicolegal liability.


Assuntos
Apendicite/epidemiologia , Imperícia/estatística & dados numéricos , Pediatria/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Estados Unidos/epidemiologia
9.
J Pediatr Surg ; 50(6): 928-32, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25805007

RESUMO

PURPOSE: Long gap esophageal atresia remains a significant treatment challenge. We aimed to create the first large animal model of long gap esophageal atresia to test a degradable esophageal lengthening device. METHODS: The distal esophagus was divided 2 cm above the gastroesophageal junction in 6 minipigs. A polycaprolactone (PCL) spring device was secured inside the distal esophageal segment, and the end was oversewn. Nonexpanding PCL tubes served as controls. An esophagogastric anastomosis was created to restore continuity. After 4 weeks, the distal esophageal pouch was analyzed. RESULTS: The distal esophageal pouch of experimental animals increased in length from 1.9 to 4.5 cm. Control animals demonstrated no change. When comparing lengthened to native esophagus, there was no difference in the thickness of muscularis mucosa or muscularis propria. Mechanically lengthened esophagus showed mild to moderate superficial inflammation and fibrosis. There were no differences in the number of myenteric or submucosal ganglia. CONCLUSION: We created the first porcine model of long gap esophageal atresia and lengthened the distal esophagus with an internally placed device. This model may be used to explore novel therapies in the management of long gap esophageal atresia.


Assuntos
Atresia Esofágica/cirurgia , Esofagoplastia/métodos , Esôfago/cirurgia , Anastomose Cirúrgica/métodos , Animais , Junção Esofagogástrica/cirurgia , Esofagoplastia/instrumentação , Masculino , Estresse Mecânico , Suínos , Porco Miniatura
10.
J Pediatr Surg ; 50(6): 954-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25818320

RESUMO

PURPOSE: Currently, animal models used for mechanical intestinal lengthening utilize a single lengthening procedure prior to analysis or restoration back into continuity. Here we developed a novel surgical model to examine the feasibility of repeated lengthening of intestinal segments. METHODS: A Roux-en-Y jejunojejunostomy with a blind Roux limb was created in rats. An encapsulated polycaprolactone spring was placed into a 1cm segment of the Roux limb. After 4 weeks, a second encapsulated PCL spring was inserted into a 1cm portion of the lengthened segment. After another 4 weeks, the repeatedly lengthened segments were retrieved for histological analyses. RESULTS: Jejunal segments of the Roux limb were successfully lengthened from 1.0 cm to 2.6 ± 0.7 cm. Four weeks after the second PCL spring placement, 1.0 cm of the previously lengthened segment increased to 2.7 ± 0.8 cm. Stronger mechanical force was required to achieve subsequent re-lengthening. Lengthened and re-lengthened segments had increased smooth muscle thickness and crypt depth when compared to normal jejunal mucosa. CONCLUSION: Using the Roux-en-Y model, previously lengthened segments of intestine can be successfully re-lengthened. Intestinal segments may be subjected to multiple lengthening procedures to achieve clinically significant length for the treatment of short bowel syndrome.


Assuntos
Jejuno/cirurgia , Expansão de Tecido/instrumentação , Expansão de Tecido/métodos , Anastomose em-Y de Roux , Anastomose Cirúrgica , Animais , Feminino , Mucosa Intestinal/cirurgia , Músculo Liso/cirurgia , Ratos Sprague-Dawley , Síndrome do Intestino Curto/cirurgia
11.
J Surg Educ ; 72(6): 1190-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26276304

RESUMO

BACKGROUND/OBJECTIVES: General surgery residents lack a standardized educational experience in pediatric surgery. We hypothesized that the development of a mobile educational interface would provide general surgery residents broader access to pediatric surgical education materials. METHODS: We created an educational mobile website for general surgery residents rotating on pediatric surgery, which included a curriculum, multimedia resources, the Operative Performance Rating Scale (OPRS), and Twitter functionality. Residents were instructed to consult the curriculum. Residents and faculty posted media using the Twitter hashtag, #UCLAPedSurg, and following each surgical procedure reviewed performance via the OPRS. Site visits, Twitter posts, and OPRS submissions were quantified from September 2013 to July 2014. RESULTS: The pediatric surgery mobile website received 257 hits; 108 to the homepage, 107 to multimedia, 28 to the syllabus, and 19 to the OPRS. All eligible residents accessed the content. The Twitter hashtag, #UCLAPedSurg, was assigned to 20 posts; the overall audience reach was 85 individuals. Participants in the mobile OPRS included 11 general surgery residents and 4 pediatric surgery faculty. CONCLUSION: Pediatric surgical education resources and operative performance evaluations are effectively administered to general surgery residents via a structured mobile platform.


Assuntos
Cirurgia Geral/educação , Internet , Internato e Residência , Aplicativos Móveis , Pediatria/educação , Humanos
13.
J Pediatr Surg ; 49(8): 1319-24; discussion 1324-5, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25092099

RESUMO

INTRODUCTION: Hirschsprung's disease is characterized by a developmental arrest of neural crest cell migration, causing distal aganglionosis. Transplanted cells derived from the neural crest may regenerate enteric ganglia in this condition. We investigated the potential of skin-derived precursor cells (SKPs) to engraft and to differentiate into enteric ganglia in aganglionic rat intestine in vivo. METHODS: Adult Lewis rat jejunal segments were separated from intestinal continuity and treated with benzalkonium chloride to induce aganglionosis. Ganglia were identified via immunohistochemical stains for S100 and ß-III tubulin (TUJ1). SKPs were procured from neonatal Lewis rats expressing enhanced green fluorescent protein (GFP) and cultured in neuroglial-selective media. SKP cell line expansion was quantified, and immunophenotypes were assessed by immunocytochemistry. Aganglionic segments underwent SKP transplantation 21-79days after benzalkonium chloride treatment. The presence of GFP+cells, mature neurons, and mature glia was evaluated at posttransplant days 1, 6, and 9. RESULTS: Benzalkonium chloride-induced aganglionosis persisted for at least 85days. Prior to differentiation, SKPs expressed S100, denoting neural crest lineage, and nestin, a marker of neuronal precursors. Differentiated SKPs in vitro expressed GFAP, a marker of glial differentiation, as well as TUJ1 and several enteric neurotransmitters. After transplantation, GFP+structures resembling ganglia were identified between longitudinal and circular smooth muscle layers. CONCLUSION: SKPs are capable of engraftment, migration, and differentiation within aganglionic rodent intestine in vivo. Differentiated SKPs generate structures that resemble enteric ganglia. Our observations suggest that SKPs represent a potential gangliogenic therapeutic agent for Hirschsprung's disease.


Assuntos
Gânglios Parassimpáticos/citologia , Doença de Hirschsprung/terapia , Crista Neural/citologia , Pele/citologia , Transplante de Células-Tronco/métodos , Animais , Animais Recém-Nascidos , Diferenciação Celular , Células Cultivadas , Modelos Animais de Doenças , Doença de Hirschsprung/patologia , Masculino , Ratos , Ratos Endogâmicos Lew
14.
J Pediatr Surg ; 49(12): 1809-14, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25487489

RESUMO

PURPOSE: Skin-derived precursor cells (SKPs) may regenerate the enteric nervous system in Hirschsprung's disease. SKPs migrate and differentiate into myenteric ganglia in aganglionic intestine. We sought to characterize the time-course of SKP gangliogenesis and enteric neurotransmitter synthesis in vivo. METHODS: Adult Lewis rat jejunal segments were isolated and denervated with benzalkonium chloride (BAC). Denervation was evaluated by immunohistochemical (IHC) stains for markers of mature neuronal and glial cells. Green fluorescent protein (GFP)-expressing neonatal rat SKPs were cultured in neuroglial-selective medium. SKPs were transplanted into aganglionic segments 65-85days after BAC treatment. IHC was performed to identify glia, neurons, and neurotransmitter synthesis in GFP+cells between post-transplant days 1 and 28. RESULTS: Aganglionosis was confirmed by IHC. On post-transplant days 1 and 2, GFP+cells were detected near injection sites within the muscularis propria. GFP+cell clusters were evident only between longitudinal and circular smooth muscle layers at post-transplant days 14, 21, and 28. These structures co-expressed markers of mature neurons and gliocytes. Several markers of neurotransmitter synthesis were detected in GFP+clusters at days 21 and 28. CONCLUSION: SKPs are capable of enteric neuroglial differentiation in vivo. SKPs migrate to the intermuscular layer of aganglionic intestine within days of transplantation. Our observations suggest that SKPs are capable of generating enteric ganglia in aganglionic intestine.


Assuntos
Sistema Nervoso Entérico/citologia , Gânglios Parassimpáticos/citologia , Doença de Hirschsprung/terapia , Jejuno/patologia , Crista Neural/citologia , Pele/citologia , Transplante de Células-Tronco/métodos , Animais , Animais Recém-Nascidos , Diferenciação Celular , Células Cultivadas , Modelos Animais de Doenças , Feminino , Doença de Hirschsprung/patologia , Jejuno/inervação , Ratos , Ratos Endogâmicos Lew
15.
J Pediatr Surg ; 49(6): 1000-3; discussion 1003, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24888851

RESUMO

PURPOSE: While bicycle helmet use reduces bicycle-related head injury, few children wear them regularly. We aimed to describe racial/ethnic and socioeconomic differences in pediatric helmet use in Los Angeles County (LAC) to help target groups for injury prevention programs. METHODS: A retrospective review of all pediatric patients involved in bicycle-related accidents in LAC between 2006 and 2011 was performed. Our primary analysis examined the association between helmet use and age, gender, insurance status, and race/ethnicity. We also evaluated the association between helmet use and the need for emergency surgery, mortality, and length of hospital stay (LOH), after adjusting for injury severity score (ISS), age, insurance status, and race/ethnicity. RESULTS: Of 1248 patients, 11.3% wore helmets, with decreased use among children 12years and older, minorities, and those without private insurance. Overall, 5.9% required an emergency operation, 34.1% returned to their pre-injury capacity, and mortality was 0.7%. On multivariable analysis, higher ISS increased LOH, the risk for emergency surgery, and mortality. CONCLUSION: Nearly 90% of children involved in bicycle-related accidents were not wearing helmets. Helmet use was lower among older children, minorities, and those from a low socioeconomic status. Injury prevention programs targeting low-income middle and high schools and minority communities may help increase helmet use in children in LAC.


Assuntos
Ciclismo/lesões , Traumatismos Craniocerebrais/etnologia , Etnicidade , Dispositivos de Proteção da Cabeça/estatística & dados numéricos , Seguro Saúde , Adolescente , Criança , Pré-Escolar , Traumatismos Craniocerebrais/economia , Traumatismos Craniocerebrais/prevenção & controle , Feminino , Humanos , Incidência , Los Angeles/epidemiologia , Masculino , Estudos Retrospectivos , Fatores Socioeconômicos
16.
J Pediatr Surg ; 49(12): 1804-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25487488

RESUMO

INTRODUCTION: Hirschsprung's disease is characterized by colonic aganglionosis, curable only by surgical correction. Stem cells may offer regenerative benefits while preventing surgical risks. Existing Hirschsprung's model systems are limited by alimentary compromise and spontaneous ganglionic reconstitution. We endeavored to generate a model of permanent colonic aganglionosis to support longitudinal cell therapy studies. METHODS: Among adult female Lewis rats (n=11), laparotomy was performed and one-centimeter segments of descending colon were isolated from continuity and denervated by trans-serosal benzalkonium chloride (BAC) exposure. Postoperative weights were plotted. The colon segments were retrieved after 50 or 100days. Immunohistochemical staining (IHC) for beta-III tubulin (TUJ1) and glial fibrillary acid protein (GFAP) revealed colonic ganglia. Muscle layer diameter and the presence of ganglia were contrasted between normal and denervated segments. RESULTS: All animals survived, experienced 5% weight loss after one week, and then consistently gained weight. Isolated segments had significantly hypertrophied smooth muscle layers compared to normal colon. Ganglia were identified by IHC in normal colonic segments, and denervated colonic segments had no IHC evidence of myenteric ganglia. CONCLUSION: Colonic segmental isolation and denervation result in an effective model of irreversible colonic aganglionosis. Animals retain alimentary function. Muscularis hypertrophy, myenteric denervation, and normal animal longevity are suitable for long-term studies of cell therapy.


Assuntos
Colo/inervação , Denervação/efeitos adversos , Gânglios/cirurgia , Doença de Hirschsprung/patologia , Animais , Colo/cirurgia , Modelos Animais de Doenças , Feminino , Doença de Hirschsprung/etiologia , Ratos , Ratos Endogâmicos Lew
17.
J Pediatr Surg ; 49(6): 971-4; discussion 974-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24888845

RESUMO

PURPOSE: Distraction enterogenesis is a potential treatment for patients with short bowel syndrome. We previously demonstrated successful lengthening of jejunum using a degradable spring device in rats. Absorptive function of the lengthened jejunum after restoration into intestinal continuity needs to be determined. METHODS: Encapsulated polycaprolactone springs were placed into isolated jejunal segments in rats for four weeks. Lengthened segments of jejunum were subsequently restored into intestinal continuity. Absorption studies were performed by placing a mixture of a non-absorbable substrate and glucose into the lumen of the restored jejunum. RESULTS: Restored jejunal segments demonstrated visible peristalsis at specimen retrieval. Compared to normal jejunal controls, restored segments demonstrated equal water absorption and greater glucose absorption. Restored segments had thicker smooth muscle, increased villus height, increased crypt depth, and decreased sucrase activity compared to normal jejunum. The density of enteric ganglia increased after restoration to near normal levels in the submucosa and to normal levels in the myenteric plexus. CONCLUSION: Jejunum lengthened with a degradable device demonstrates peristaltic and enzymatic activity as well as glucose and water absorption after restoration into intestinal continuity. Our findings further demonstrate the therapeutic potential of a degradable device.


Assuntos
Jejuno/fisiopatologia , Peristaltismo , Síndrome do Intestino Curto/terapia , Expansão de Tecido/métodos , Animais , Modelos Animais de Doenças , Feminino , Jejuno/cirurgia , Ratos , Ratos Sprague-Dawley , Síndrome do Intestino Curto/fisiopatologia , Estresse Mecânico
18.
J Pediatr Surg ; 49(12): 1791-4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25487485

RESUMO

PURPOSE: Current animal models of mechanical lengthening separate intestinal segments from enteric continuity. Such models are difficult to use for repeated lengthening procedures and result in intestinal tissue loss during restoration into continuity. We sought to create a novel surgical model to allow multiple lengthening procedures for the purpose of maximizing the net increase in tissue after intestinal lengthening. METHODS: A Roux-en-y jejunojejunostomy with a 6-cm blind-ended Roux limb was created in the proximal jejunum of rats. Encapsulated 1-cm polycaprolactone springs were placed into the closed end of the roux limb and secured with a vessel loop. After 4weeks, lengthened segments and normal jejunum were retrieved for histologic analysis. RESULTS: Jejunal segments were lengthened from 1.0cm to 3.0cm. Lengthened segments had increased smooth muscle thickness, fewer submucosal ganglia, and similar numbers of myenteric ganglia compared to normal intestine. When compared to normal jejunal mucosa, lengthened segments demonstrated unchanged villus height and increased crypt depth. CONCLUSIONS: We created an innovative surgical model for intestinal lengthening and successfully lengthened jejunal segments with a degradable spring. The Roux-en-y model may allow the use of a degradable spring for the treatment of short bowel syndrome.


Assuntos
Jejuno/cirurgia , Síndrome do Intestino Curto/cirurgia , Expansão de Tecido/métodos , Animais , Modelos Animais de Doenças , Feminino , Músculo Liso/cirurgia , Ratos , Ratos Sprague-Dawley
19.
J Pediatr Surg ; 49(1): 109-13; discussion 113, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24439592

RESUMO

PURPOSE: Previous studies demonstrated successful mechanical lengthening of rat jejunum using an encapsulated Nitinol spring device over a stabilizing guidewire. We sought to improve the applicability of intestinal lengthening by creating a biodegradable device. METHODS: Using properties of the Nitinol spring device, polycaprolactone (PCL) springs with similar outer diameter and spring constant were created. After in vitro testing in dry and hydrated environments, they were used to lengthen 1-cm isolated segments of rat jejunum in vivo. Retrieved segments were analyzed histologically. RESULTS: Optimal PCL spring devices had an average spring constant 1.8 ± 0.4 N/m, pitch 1.55 ± 0.85 mm, and band width 0.825 ± 0.016 mm. In vitro testing demonstrated stable spring constants. Jejunal segments were lengthened from 1.0 cm to 2.7 ± 0.4 cm without needing a stabilizing guidewire. Histology demonstrated increased smooth muscle thickness and fewer ganglia compared to controls. Lengthened jejunum was successfully restored into intestinal continuity and demonstrated peristalsis under fluoroscopy. CONCLUSIONS: A novel biodegradable spring device was successfully created and used to mechanically lengthen intestinal segments. Use of a biodegradable device may obviate the need for retrieval after lengthening. This improves device applicability and may be useful for the treatment of short bowel syndrome.


Assuntos
Implantes Absorvíveis , Implantes Experimentais , Jejuno/ultraestrutura , Dispositivos para Expansão de Tecidos , Expansão de Tecido/métodos , Anastomose Cirúrgica , Animais , Cápsulas , Sistema Nervoso Entérico/ultraestrutura , Desenho de Equipamento , Feminino , Fluoroscopia , Músculo Liso/ultraestrutura , Peristaltismo , Poliésteres , Ratos , Ratos Sprague-Dawley , Estresse Mecânico
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