短肠综合征的营养策略

短肠综合征是儿童肠衰竭的主要原因,由于手术切除、先天性缺陷或与疾病相关的吸收丧失引起,在常规正常饮食下无法维持蛋白质-能量、体液、电解质以及微量营养素的平衡,需要专门的营养治疗,治疗的目标是促进肠道适应以达到肠道自主,同时保持健康的生长和发育。营养治疗策略是异质的和复杂的,须量身定制。对肠外、肠内和口服营养的类型和持续时间尚无循证建议。提倡阶段化营养管理,肠外营养对于短肠综合征的婴儿和儿童的生存至关重要,谨慎的营养策略对于减少肠外营养持续时间以及降低肠外营养相关并发症发生的风险至关重要,鉴于肠道适应的需要,早期开始最低限度的喂养、根据肠道耐受性逐渐增加肠内营养的量、经口腔喂养以及多样化平衡饮食是必要的。母乳和混合饮食是不错的选择。     

关注危重患儿肠外营养规范应用

肠外营养（PN）是危重患儿肠功能衰竭或肠内喂养障碍时的主要营养支持治疗方法。准确评估危重患儿的营养状况及能量需求有助于更好地实施PN策略。最佳的PN时机尚未确定,但目前倾向于晚期开始。“全合一”是推荐的肠外营养模式。在危重成人患者中,已经不同程度地推荐使用药理营养素,但在儿科还须更深入的研究。     

Overview of pediatric short bowel syndrome

Short bowel syndrome (SBS) is a malabsorptive state occuring as a result of surgical resection or congenital disease of a significant portion of the small intestine . The amount of resection or remaining bowel generally dictates the degree of malabsorption and consequentely the need for specialized enteral nutrition or parenteral nutrition (PN). Intestinal failure in the context of SBS is defined as a dependence on PN to maintain minimal energy and fluid requirement for growth in children. Common causes of SBS in infants and children include necrotizing enterocolitis, midgut volvulus, intestinal atresia, and gastroschisis. Early identification of patients at risk for long-term PN dependency is the first step toward avoiding severe complications. Close monitoring of nutritional status, steady and early introduction of enteral nutrition, and aggressive prevention, diagnosis, and treatment of infections such as central venous catheter sepsis and bacterial overgrowth can significantly improve the prognosis. Intestinal transplantation is an emerging treatment that may be considered when intestinal failure is irreversible and children are experiencing serious complications related to TPN administration.     

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??Parenteral nutrition has become a mainstay in the treatment of critically ill children with intestinal or conditions that preclude enteral feeding. Accurate assessment of nutritional status and energy requirements in critically ill children will help to better implement the strategy of parenteral nutrition. The timing of the optimal parenteral nutrition has not been determined??and at present the supplementary parenteral nutrition tends to be started at a later stage. “All in one” is recommended for parenteral nutrition. Pharmacological nutrients have been recommended in critically ill adult patients with different levels??but more extensive research is still needed in critically ill children.     

Indications for pediatric intestinal transplantation: a position paper of the American Society of Transplantation

Parenteral nutrition represents standard therapy for children with short bowel syndrome and other causes of intestinal failure. Most infants with short bowel syndrome eventually wean from parenteral nutrition, and most of those who do not wean tolerate parenteral nutrition for protracted periods. However, a subset of children with intestinal failure remaining dependent on parenteral nutrition will develop life-threatening complications arising from therapy. Intestinal transplantation (Tx) can now be recommended for this select group. Life-threatening complications warranting consideration of intestinal Tx include parenteral nutrition-associated liver disease, recurrent sepsis, and threatened loss of central venous access. Because a critical shortage of donor organs exists, waiting times for intestinal Tx are prolonged. Therefore, it is essential that children with life-threatening complications of intestinal failure and parenteral nutrition therapy be identified comparatively early, i.e. in time to receive suitable donor organs before they become critically ill. Children with liver dysfunction should be considered for isolated intestinal Tx before irreversible, advanced bridging fibrosis or cirrhosis supervenes, for which a combined liver and intestinal transplant is necessary. Irreversible liver disease is suggested by hyperbilirubinemia persisting beyond 3-4 months of age combined with features of portal hypertension such as splenomegaly, thrombocytopenia, or prominent superficial abdominal veins; esophageal varices, ascites, and impaired synthetic function are not always present. Death resulting from complications of liver failure is especially common during the wait for a combined liver and intestinal transplant, and survival following combined liver and intestinal Tx is probably lower than following an isolated intestinal transplant. The incidence of morbidity and mortality following intestinal Tx is greater than that following liver or kidney Tx, but long-term survival following intestinal Tx is now at least 50-60%. It is probable that outcomes shall improve in the future with continued refinements in operative technique and post-operative management, including immunosuppression.     

Prevention of parenteral nutrition-associated liver disease in children

Liver injury is associated with parenteral nutrition therapy. Severity of injury varies from minimal and transient increases in liver-related blood tests to biliary cirrhosis and liver failure. Severe parenteral nutrition-related liver disease is usually confined to patients who have undergone massive intestinal resection. In these patients, early sepsis appears to cause initial liver injury, and recurring sepsis and inflammation, local or systemic, may result in its perpetuation and progression. Liver disease associated with parenteral nutrition is not necessarily related either to duration of parenteral nutrition or to delayed intestinal feeding. However, treatment includes enteral nutrition to promote enterohepatic circulation of bile acids and management of inflammation and sepsis, including control of intestinal bacterial overgrowth. Restriction of intravenous lipid emulsions may be important. The clinical picture of advanced liver failure related to short bowel syndrome differs from liver failure with an anatomically normal gastrointestinal tract. In the former, hyperbilirubinemia, hepatosplenomegaly, and functional hypersplenism dominate the clinical picture, and severe ascites and esophageal variceal hemorrhage are unusual. Early referral of these patients for intestinal and/or liver transplantation may provide the best chance for long-term survival.     

Current issues in the management of intestinal failure

Successful long term parenteral nutrition has transformed the prognosis for children with irreversible intestinal failure in the last three decades, but has also highlighted the long term complications: intestinal failure associated liver disease; recurrent catheter sepsis; and impaired venous access. Recent advances in small bowel transplantation and non-transplant surgical techniques now offer hope of sustained survival in the future without parenteral nutrition.     

Current issues in the management of intestinal failure.

Successful long term parenteral nutrition has transformed the prognosis for children with irreversible intestinal failure in the last three decades, but has also highlighted the long term complications: intestinal failure associated liver disease; recurrent catheter sepsis; and impaired venous access. Recent advances in small bowel transplantation and non-transplant surgical techniques now offer hope of sustained survival in the future without parenteral nutrition.     

Preventing parenteral nutrition liver disease

Parenteral nutrition liver disease (PNLD) develops in 40-60% of infants who require long-term PN for intestinal failure. The clinical spectrum includes hepatic steatosis, cholestasis, cholelithiasis, and hepatic fibrosis. Progression to biliary cirrhosis and the development of portal hypertension and liver failure occurs in a minority who require combined liver and intestinal transplantation.The pathogenesis is multifactorial and is related to prematurity, low birth weight, duration of PN, short bowel syndrome requiring multiple laparotomies and recurrent sepsis. Other important mechanisms include lack of enteral feeding which leads to reduced gut hormone secretion, reduction of bile flow and biliary stasis which leads to the development of cholestasis, biliary sludge and gallstones, which exacerbate hepatic dysfunction, especially in premature neonates with immature hepatic function.The use of lipid emulsions, particularly soy bean emulsions have been associated with hepatic cholestasis in children, although there are little data now to support toxicity from other PN components.Management strategies for the prevention of parenteral nutrition liver disease include consideration of early enteral feeding, a multidisciplinary approach to the management of parenteral nutrition with a specialized nutritional care team and aseptic catheter techniques to reduce sepsis. The use of specialized lipid emulsions such as fish oil emulsions and or SMOF (Soy bean/Medium Chain Triglyceride/Olive Oil/Fish oil) improves established cholestasis and may prevent the onset.Oral administration of ursodeoxycholic acid may improve bile flow and reduce gall bladder stasis, although there is little data to suggest that prophylactic use prevents the onset of PNLD.Survival following either isolated small bowel or combined liver and small bowel transplantation is approximately 50% at 5 years making this an acceptable therapeutic option in children with irreversible liver and intestinal failure.     

Supportive care for children with cancer. Guidelines of the Childrens Cancer Study Group. The use of nutritional therapy

Nutritional support for children with cancer is predicated on the belief that optimal nutrition promotes tolerance of anti-neoplastic therapy and preserves immunologic responsiveness. The use of nutritional support is based on the assumption that there is effective therapy for the primary disease and that there will be a predictable period of nutritional stress. The most common nutritional problem is posed by the failure of sick children willingly to eat enough to maintain nutritional homeostasis. Supplementation of oral intake with a nutritional formula given by a small-bore nasogastric tube is simple, effective, and economical. If the sum of oral and tolerated nasogastric tube feedings is less than that required for optimal nutrition, unmet needs may be satisfied by nutrients given into a peripheral vein. Total parenteral nutrition, given by central vein, is reserved for situations in which the combination of enteral and peripheral venous alimentation is inadequate.     

Extensive resection of the small intestine in children

Thirteen children aged 2 to 16 years have had a subtotal resection of small bowel, following a mid-gut volvulus in 10 cases. All children are still alive, and their growth was normal; 36 cumulative patient-years of parenteral nutrition and 11 years of constant rate enteral nutrition were performed. In 7 cases, where residual small bowel varied between 30 to 120 cm, termination of all artificial nutritional support was possible at a mean of 30 months after intestinal resection. On the other hand if resection was near total with less than 20 cm remaining, life long dependence on parenteral nutrition is unavoidable unless intestinal transplantation becomes feasible; with cyclic parental nutrition at home, their quality of life is near normal.     

Nutritional support for pediatric patients with inflammatory bowel disease

Pediatric patients with ulcerative colitis and Crohn's disease often suffer from malnutrition and growth failure. This is particularly true in pubertal children. Chronic insufficient nutrient intake is most often the cause of growth failure. Both parenteral nutrition and defined enteral formulas are available to rehabilitate patients with malnutrition and growth failure. Assessment of nutritional status and growth and the use of parenteral nutrition and defined enteral formulas to reverse malnutrition, growth failure, and inflammation in pediatric patients with inflammatory bowel disease are discussed.     

Home parenteral nutrition in chronic intestinal failure.

In children with severe failure of intestinal function, intravenous nutrition is at present the only treatment able to maintain adequate nutrition for prolonged periods of time. Over the last five years we have discharged 10 patients home on parenteral nutrition for a total of 25 patient years and here the outcome of these children is presented. Of the 10 patients, one has discontinued home parenteral nutrition (HPN), seven patients remain well, one patient has recently moved to the USA, and one patient has died after major abdominal surgery. All children had either normal or an accelerated rate of growth on HPN and developmentally all have progressed well. All the children over 5 years attend normal schools. The major complication of treatment was line sepsis with an overall rate of one episode in 476 days and a total of nine central lines (five patients) have required replacement giving an average line life of 680 days. For those children unfortunate enough to suffer from severe intestinal failure, HPN is preferable to prolonged hospital treatment and offers the chance of a good quality of life with prolonged survival.     

Selected topics in therapeutic nutrition

Although parenteral and enteral nutrition has advanced rapidly in the last 5 years, prevention of nutritional problems in children still depends on the practice of basic nutritional principles. Breast-feeding remains the best alimentation for the infant. Increased support of breast-feeding in children with cleft lip and/or palate is a simple application of basic therapeutic nutrition. Proper feeding can avert the need for parenteral or enteral nutrition. As our knowledge of nutritional therapeutics expands, the practitioner will be able to play a greater role in both preventive and therapeutic nutrition.     

Home parenteral nutrition in chronic intestinal failure

In children with severe failure of intestinal function, intravenous nutrition is at present the only treatment able to maintain adequate nutrition for prolonged periods of time. Over the last five years we have discharged 10 patients home on parenteral nutrition for a total of 25 patient years and here the outcome of these children is presented. Of the 10 patients, one has discontinued home parenteral nutrition (HPN), seven patients remain well, one patient has recently moved to the USA, and one patient has died after major abdominal surgery. All children had either normal or an accelerated rate of growth on HPN and developmentally all have progressed well. All the children over 5 years attend normal schools. The major complication of treatment was line sepsis with an overall rate of one episode in 476 days and a total of nine central lines (five patients) have required replacement giving an average line life of 680 days. For those children unfortunate enough to suffer from severe intestinal failure, HPN is preferable to prolonged hospital treatment and offers the chance of a good quality of life with prolonged survival.     

Long-term outcomes of pediatric intestinal failure

Management of pediatric intestinal failure has evolved in recent decades, with improved survival since the advent of specialized multidisciplinary intestinal failure centers. Though sepsis and intestinal failure associated liver disease still contribute to mortality, we now have growing data on the long-term outcomes for this population. While intestinal adaptation and parenteral nutrition weaning is most rapid during the first year on parenteral support, achievement of enteral autonomy is possible even after many years as energy and protein requirements decline dramatically with age. Intestinal transplant is an option for patients experiencing complications of long-term parenteral nutrition who are expected to have permanent intestinal failure, but outcomes are hindered by immunosuppression-related complications. Much of the available data comes from single center retrospective reports, with variable inclusion criteria, intestinal failure definitions, and follow-up durations; this limits the ability to analyze outcomes and identify best practices. As most children now survive long-term, the focus of management has shifted to the avoidance and management of comorbidities, support of normal growth and development, and optimization of quality of life for these medically and surgically complex patients.     

Nutritional support for children with cancer

Children with cancer are at risk of suffering from under nutrition, which can affect tolerance of therapy and may influence their overall survival. The goals of nutritional support in the cancer patient are to achieve and maintain desirable weight and to prevent or correct nutritional deficiencies. So early identification of patients at high risk for malnutrition is essential. There are different options for nutritional support. Oral feeding, when possible, is the first line. Enterai nutrition should be considered for those patients who cannot consume adequate macronutrients by mouth. Options are nasogastric tube or gastrostomy tube feeding. The advantages of enterai nutrition, when compared with parenteral nutrition, include better maintenance of the structural and functional integrity of the gastrointestinal tract, a decreased risk of bacterial translocation, greater ease and safety of administration, more physiologic and efficient use of nutrient substrates, decreased hepato-biliary complications, improved outcome and cost-effectiveness. Thus, parenteral nutrition should be considered if the gut is not functioning adequately to allow the normal absorption and digestion of nutrients or if enterai nutritional support is not sufficient to meet nutritional needs. Nutritional assessment and support should be integrated into treatment protocols for all children with neoplastic diseases.     

The importance of enteral nutrition to prevent or treat undernutrition in children undergoing treatment for cancer

Nutrition therapy is a therapeutic approach to treating medical conditions and symptoms via diet, which can be done by oral, enteral or parenteral routes. It is desirable to include nutritional interventions as a standard of care in pediatric cancer units (PCUs) at all levels of care. The interventions are dependent on available resources and personnel across all clinical settings. Enteral nutrition is easy, inexpensive, uses the gastrointestinal tract, maintains gut mucosal integrity, and allows for individualized nutritional strategies. This narrative review describes enteral nutritional interventions for children undergoing cancer treatment and is aimed at PCUs of all levels of care located in a low‐ and middle‐income country.     

Natural history of intestinal failure,investigated through a national network-based approach

OBJECTIVES: Intestinal failure (IF) is a condition whose treatment requires advanced knowledge and techniques and a multidisciplinary approach. Intestinal failure is the endpoint of many intestinal diseases and may result in full recovery, in life-long parenteral nutrition, or in the death of the child. The aim of this study was to evaluate the natural history of IF in children using a national network of resources. METHODS: Italian centers of pediatric gastroenterology merged in a national network, developing a collaborative management approach for children with IF. A consensus definition of IF was achieved. A database was set up to investigate the cause, epidemiologic factors, and natural history of IF. RESULTS: One hundred nine children were enrolled in 5 years. The cause of IF was: short bowel syndrome (n = 48), disorders of motility (n = 16), structural enterocyte defects (n = 14), multiple food intolerance (n = 10), autoimmune enteropathy (n = 7), and others or unknown (n = 14). The eventual outcome was closely related to the primary cause, ranging from full and permanent intestinal sufficiency in children with multiple food intolerance to high death rate or total dependance upon parenteral nutrition in those with structural enterocyte defects. Intermediate outcomes were observed for the other causes. Four children received intestinal transplantation. CONCLUSIONS: The network approach for IF provides an effective model to optimize resources and to investigate prospectively the natural history of IF. Based on the work on this series, a European network for IF could be an effective model for fulfilling the diagnostic and management needs, including intestinal transplantation.     

Superior vena cava thrombosis causing respiratory obstruction successfully resolved by stenting in a small bowel transplant candidate.

A 4 year old child was referred for small bowel transplantation. He had superior vena cava obstruction secondary to numerous central venous line placements; alternative routes for long term central venous access were compromised by extensive venous occlusive disease. Patency for the superior vena cava was re-established with stenting, which allowed for radiological placement of another central venous line. Long term survival in infants and young children with intestinal failure is dependent on adequate central venous access for the administration of parenteral nutrition. Line sepsis and physical damage to the catheter often necessitates multiple central venous catheter placements during their early life and these children are at risk of catheter related veno-occlusive disease. Recurrent sepsis and the loss of satisfactory venous access for the administration of parenteral nutrition is life threatening and is an indication for intestinal transplantation in up to 41% of patients reported by the small bowel registry.