Seminars in pediatric surgery
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Extracorporeal life support (ECLS) denotes the use of prolonged extracorporeal cardiopulmonary bypass in patients with acute, reversible cardiac or respiratory failure. As technology has advanced, organ support functions other than gas exchange, such as liver, renal, and cardiac support, have been provided by ECLS, and others, such as immunologic support, will be developed. The future of ECLS will include improvements in devices accompanied by circuit simplification and auto-regulation. ⋯ As the ECLS technique becomes safer and simpler, and as morbidity and mortality are minimized, criteria for application of ECLS will be relaxed. New approaches to ECLS, such as pumpless arteriovenous bypass, the artificial placenta, arteriovenous CO(2) removal (AVCO(2)R), and intravenous oxygenators (IVOX), will become more commonly applied. Such advances in technology will allow broader and more routine application of ECLS for lung and other organ system failure.
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Polycystic ovary syndrome (PCOS) has traditionally been thought of as a triad of oligomenorrhea, hirsutism, and obesity. PCOS is now recognized as a heterogeneous disorder that results in overproduction of androgens primarily from the ovary leading to anovulation and hirsutism and is associated with insulin resistance. Symptoms in the adolescent include oligomenorrhea, hirsutism, acne, and weight gain. ⋯ Treatment should be instituted early to decrease symptoms and long-term sequellae of PCOS. Weight loss, oral contraceptives and antiandrogens are very effective in treating the symptoms of this disorder. Insulin-sensitizing medications show promise, but should be used with caution until larger randomized trials have shown short- and long-term benefit and efficacy over traditional therapies in the adolescent population.
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Semin. Pediatr. Surg. · Feb 2005
ReviewDisordered enterocyte signaling and intestinal barrier dysfunction in the pathogenesis of necrotizing enterocolitis.
Necrotizing enterocolitis (NEC) is the leading cause of death from gastrointestinal disease in neonates, and is characterized by the development of diffuse intestinal necrosis in the stressed, pre-term infant. Systemic stress causes a breakdown in the intestinal mucosal barrier, which leads to translocation of bacteria and endotoxin and the initiation of a signaling response within the enterocyte. This review summarizes recent evidence defining a clear role that defective enterocyte signaling plays in the pathogenesis of NEC through the following mechanisms: 1) The localized production of nitric oxide by villus enterocytes results in an increase in enterocyte apoptosis and impaired proliferation; 2) The translocation of endotoxin results in a PI3K-dependent activation of RhoA-GTPase within the enterocyte leading to decreased enterocyte migration and impaired restitution; 3) Dysregulated sodium-proton exchange within the enterocyte by endotoxin renders the enterocyte monolayer more susceptible to damage in the face of the acidic microenvironment characteristic of systemic sepsis; and 4) Endotoxin causes a p38-dependent release of the pro-inflammatory molecule COX-2 by the enterocyte, which potentiates the systemic inflammatory response. An understanding of the mechanisms by which disordered enterocyte signaling contributes to the pathogenesis of barrier failure and NEC--through these and other mechanisms--may lead to the identification of novel therapeutic approaches for this devastating disease.
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Semin. Pediatr. Surg. · Aug 2004
ReviewSedation and analgesia for procedures outside the operating room.
The volume of literature concerning sedation and analgesia for procedures outside the operating room has increased greatly over the past several years. Information relating to sedation risks and complications, the development of sedation guidelines, and now specific sedation techniques has appeared. ⋯ The risks and complications associated with sedation will be addressed and an approach to providing sedation and analgesia for procedures outside the operating room will be presented. The important characteristics of several common drugs used for sedation and analgesia will also be discussed.
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Neonates with functional single ventricles have pulmonary and systemic circulations that are supplied in parallel, creating significant cyanosis and ventricular volume overload. The goal of palliative surgery, excluding transplantation, is to convert single-ventricle circulation from a parallel to a series arrangement. This will ultimately require a complete cavopulmonary anastomosis (Fontan-type procedure) in which vena caval blood is rerouted directly into the pulmonary circulation. ⋯ Patients who have undergone stage III surgery, the Fontan-type repair, vary in age from toddlers to adults, and in physical status from well-compensated to significantly debilitated. Fontan patients require thorough preoperative assessment when elective surgery is contemplated. Optimal communication between surgeons, anesthesiologists, and cardiologists is essential when caring for the patient with single-ventricle physiology.