Effect of starvation and total parenteral nutrition on electrolyte homeostasis in normal man

Elemental balances, and skeletal muscle membrane potential (Em) and biopsy were utilized to evaluate electrolyte homeostasis and body composition in 11 healthy adult volunteers after 10 days of starvation. This controlled, acute malnutrition was followed by refeeding for 10 days with two different, commonly used, total parenteral nutrition (TPN) solutions. Six subjects were refed with crystalline amino acids and dextrose (dextrose group), while five subjects received amino acids, dextrose, and lipid (lipid group). During starvation, negative balances for potassium, phosphorous, magnesium, and nitrogen were observed in both groups. When compared to starvation, total parenteral nutrition produced statistically significant (p less than 0.05) equilibrium or positive electrolyte and nitrogen balances for both, the dextrose and lipid groups. During TPN, there was a significantly (p less than 0.001) positive chloride balance in the lipid group when compared to the dextrose group. At the conclusion of the 10-day period of TPN, there was a decrease (p less than 0.05) in skeletal muscle Em. This change, in concert with the electrolyte balance data obtained during parenteral repletion, lead us to postulate that restoration of lean tissue protein and cellular function does not occur at a rate which might be inferred from the positive nitrogen balance observed in this model. A persistent defect in cellular function which was evident after starvation, suggests that a brief period of TPN is insufficient to restore skeletal muscle integrity.     

肠外与肠内营养对胰腺外分泌和急性重症胰腺炎的影响

肠外营养(PN)不能改变胰腺炎自然病程,能降低并发症和病死率,但导管感染和肠源性并发症增加。近年来,肠内营养（EN）应用受到重视,但在急性重症胰腺炎（SAP）中的应用仍有争议。从EN对胰腺外分泌和SAP自然病程的影响分析,提出经空肠喂养不会刺激胰腺分泌,也不会加重SAP的病情。在临床实际应用中,应结合SAP的分期和临床状况,采用PN和EN联合应用来达到营养支持的目的。     

全胃切除术后早期肠内肠外营养的对比研究

目的：探讨全胃切除术后早期肠内营养（EEN）与全肠外营养（TPN）对患者营养状况的改善及并发症发生率的影响。方法：将86例接受根治性全胃切除的胃癌患者随机分为EEN组和TPN组。EEN组手术后第1天开始分别给予营养支持,于术前1天、术后8天检测体重、血常规、肝功能、前白蛋白和C-反应蛋白,并观察并发症的发生率和平均住院费用。结果：EEN组体重、白蛋白、前白蛋白下降幅度和白细胞、转氨酶、C-反应蛋白升高幅度均少于TPN组。EEN组患者吻合口瘘、肺部感染、切口愈合不良等并发症发病率低于TPN组。EEN组的平均住院费用低于TPN组。结论：术后EEN较TPN能改善全胃切除术后患者的营养状况,降低并发症发生率,减少经济费用。     

Copper deficiency in an infant on prolonged total parenteral nutrition

An infant with the megacystis microcolon intestinal hypoperistalsis syndrome, required total parenteral nutrition due to ineffective gastrointestinal function, and developed copper deficiency after a prolonged course in total parenteral nutrition in conjunction with a chronic draining jejunostomy. She responded promptly to copper supplementation.     

Plasma vitamin levels in patients on prolonged total parenteral nutrition

Vitamins are essential in total parenteral nutrition (TPN), their importance being highlighted by repeated past documentation of various vitamin deficiencies particularly in patients on long-term parenteral nutrition therapy. This study evaluated the efficacy of water- (Soluvit) and fat-soluble (Vitalipid) vitamin supplementation in patients receiving total parenteral nutrition using the three in one 3-liter bag system. All patients received water-soluble vitamin supplements daily. Fat-soluble vitamin supplements were administered on a daily or twice weekly basis. Twenty-two patients were studied. In seven of the 22 patients vitamin status was assessed on more than one occasion during TPN support, thus bringing the total number of observations to 30. The mean duration of TPN support was 35 days. Eight of the observations were made during less than 10 days, three between 11-19 days, 15 between 20-60 days, and four during more than 60 days of TPN support. Biochemical deficiency as judged by subnormal enzyme activity or vitamin levels were present in 10% of the patients for thiamin, 3% for riboflavin, and 6% for nicotinic acid. By contrast 83% of the patients had low plasma vitamin C and B6 levels. Low plasma vitamin A and E levels were also present in 43 and 40% of the patients, respectively. According to the plasma concentrations of the vitamins studied it would appear that the commercial vitamin preparations used in this study are inadequate in maintaining optimal vitamin status.(ABSTRACT TRUNCATED AT 250 WORDS)     

早期全肠外营养及肠内、外混合营养对神经外科危重患者免疫功能的影响

目的探讨早期给予全肠外营养（TPN）及肠内营养（EN）、肠外营养（PN）混合支持对神经外科危重患者免疫功能的影响。方法采用前瞻性对照研究将神经外科危重患者按入院顺序随机分为TPN组及EN＋PN组,并对比营养支持前后两组CD3、CD4、CD8、CD4／CD8、CD3／CD25、IgA、IgG、IgM、血清白蛋白的变化。结果给予神经外科危重患者两种营养支持均可提高其CD3、CD4、CD8及CD3＋／CD25＋比值（P〈0．05,P〈0．01）;两种营养支持方式均可显著升高IgA、IgG、IgM、（P〈0．05）及血清白蛋白浓度（P〈0．01）。与TPN组比较,EN＋PN组CD3、CD4、CD8、CD4／CD8比值、IgA、IgG、IgM浓度及血清白蛋白水平均显著升高（P〈0．05,P〈0．01）。结论早期TPN及EN＋PN支持均可促进神经外科危重患者免疫功能的恢复及提高,EN＋PN的作用优于TPN,对于神经外科危重患者应早期给予营养支持治疗。     

肠外营养对电解质平衡影响的实验研究

将20只雄性SD大鼠随机分成给氮组和无氮组,每组各10只。按千克体重供给非蛋白质热卡、水和电解质,给氮组另供给氮。通过中心静脉置管,将营养液注入大鼠体内。每日收集24h尿液,测定尿液中电解质和氮的含量,实验持续6天。用给入量减去排出量得各种元素的平衡。结果,给氮组获正电解质和正氮平衡,无氮组获负电解质和负氮平衡。本结果说明,在肠外营养支持时,机体在获正氮平衡的同时,获正电解质平衡。     

Effects of enteral and parenteral nutrition on appetite in monkeys.

Varied clinical observations of the presence of either hunger or anorexia during intragastric or intravenous alimentation have led to the current experiments. Nine rhesus monkeys (Macaca mulatta) were involved in studies of the long-term effects of enteral and parenteral nutrition on appetite as assessed by feeding behavior and gastric motility. The monkeys received either intragastric infusions of glucose or a complete liquid diet, or intravenous infusions of glucose or glucose/amino acid solutions. Oral intake was accurately adjusted to account for the calories administered by the intragastric route. Oral intake was also reduced in a calorically equivalent amount to account for the calories received during intravenous glucose. When glucose/amino acid solutions were administered parenterally, adjustments were less accurate, with resultant overeating and weight gain in some monkeys during parenteral nutrition, followed by prolonged suppression of appetite after cessation of the infusions. Further studies of the effects of varied compositions of parenteral nutrition, and varied methods of weaning from infusions, are indicated.     

Total parenteral nutrition and enteral nutrition in diabetes

A quarter or more of critically ill patients are likely to have carbohydrate intolerance or frank diabetes, either pre-existing or secondary to the stress of illness. Those patients who require parenteral nutrition should be treated using regimens similar to those used in nondiabetic patients, along with sufficient insulin (given by separate infusion) to maintain near-normal glycaemia. The role of novel substrates in diabetes remains to be established. In patients who require enteral nutrition, there is accumulating evidence that high-fat (as monounsaturated fatty acid) formulations achieve better overall metabolic control than conventional high-carbohydrate preparations. In view of the fact that macrovascular disease is the major cause of morbidity and mortality in type 2 diabetes in particular, and the fact that the risk of macrovascular complications is relatively unaffected by glycaemic control, the improved lipid and haemostatic profile achieved with preparations that are high in monounsaturated fatty acids is of particular importance in patients on long-term nutritional support.     

重症急性胰腺炎早期肠内外营养支持的临床对比研究

目的 分析比较肠内与肠外营养支持对重症急性胰腺炎(SAP)患者的影响,从而探讨经胃镜放置鼻空肠营养管行肠内营养支持在SAP中的临床应用价值.方法 分析2003年3月至2008年3月因SAP住院的患者,其中经胃镜放置鼻空肠营养管行早期肠内营养支持的患者35例(NENE组),并选择同期行完全胃肠外营养支持的患者35例作为对照组(TPN组),比较两组患者治疗前、治疗后1、2、3、4周血红蛋白、血清白蛋白、血肌酐、血胆固醇、三酰甘油及空腹血糖水平的变化,以及治疗前、治疗后4周免疫功能水平,并比较两组患者的住院时间、住院费用、各种并发症的发生情况和病死率.结果 治疗后,两组患者营养状况均有改善,但NENE组的血红蛋白升高和空腹血糖的下降较TPN组更为明显(P<0.05).而免疫功能测定表明治疗后NENE组IgA、CD4/CD8明显高于TPN组(P<0.05).而并发症方面,NENE组发生率明显低于TPN组(P<0.05).此外,NENE组的平均住院时间和住院费用明显少于TPN组[分别为(38.46±20.08)d比(57.75±26.69)d与(60716.24±42 357.35)元比(93 852.70±76493.62)元](P<0.01);但两组病死率比较差异无统计学意义(P>0.05).结论 SAP患者应尽早给予肠内营养有利于改善全身营养状况,增强机体免疫功能,显著减少各种感染、多脏器功能衰竭等并发症的发生率,缩短患者的住院时间和住院费用,其价值更优于TPN.     

Gastric pepsin and acid secretion during total parenteral nutrition and constant-rate enteral nutrition in infancy

Total Parenteral Nutrition (TPN) and constant rate enteral nutrition (CREN) are widely used: their effects on gastric function, especially pepsin secretion, are unknown. Basal and pentagastrin-stimulated pepsin (BPO, MPO) and acid (BAO, MAO) secretions were measured in three groups of infants: controls (14 infants fed normally), TPN groups (seven infants on TPN), CREN groups (14 infants on CREN). The MAO and MPO of the TPN group were significantly lower than controls (p less than 0.02), and the ratio of pentagastrin-stimulated PO/AO did not change, suggesting a large decrease of acid gastric function in the TPN group. BPO was not different from controls and BAO was significantly higher because of amino acids perfusion. The data for CREN group were not different from those of the control group, despite the fact that 11 infants were on TPN before CREN. These results demonstrate that TPN causes decreases in both acid and pepsin secretions in human infants. When TPN children are placed on CREN, these secretions return to normal.     

肠内肠外营养的并发症

文中阐述了肠内、肠外营养的并发症。胃肠道外营养的并发症主要有:(1)导管并发症;(2)感染并发症;(3)代谢并发症。肠道内营养的主要并发症是腹泻、恶心呕吐、倾倒综合征及代谢并发症。依靠健全的营养支持来管理肠外、肠内营养是减少各类并发症的中心环节。特别对长期需要肠外营养的家庭TPN病人营养支持组的管理和指导更属重要。     

Effects of cyclic (nocturnal) total parenteral nutrition and continuous enteral nutrition on circadian rhythms of blood lipids, lipoproteins and apolipoproteins in humans

The aim of the present study was to investigate the occurrence and characteristics (acrophase, amplitude) of circadian rhythms of serum total cholesterol, free-fatty acids (FFA), triglycerides, lipoproteins (HDL-, LDL-, and VLDL-cholesterol), apolipoproteins A and B, glucose and total proteins in hospitalized patients fed with 12 h nocturnal total parenteral nutrition (TPN) (from 8 PM to 8 AM) including lipids, patients fed with continuous enteral nutrition over 24 h daily spans, and patients eating 3 meals a day serving as controls. All the subjects were synchronized with diurnal activity and nocturnal rest in the hospital routine. The results showed the following: 1) circadian rhythms of total cholesterol, triglycerides, FFA, HDL-, LDL-cholesterol, apolipoprotein A and total proteins were detected in both TPN patients and controls, rhythms of apolipoprotein B and glucose in TPN patients only; in enteral nutrition patients, rhythms were detected for total proteins, glucose and triglycerides only; 2) a significant shift in triglyceride and FFA acrophases was observed in TPN patients, as compared with controls; 3) 24 h mean of both triglyceride and cholesterol concentrations remained unchanged after one month, in both TPN and enteral nutrition patients. The present approach, by extending results of previous investigations, leads one to conclude that, on both a metabolic and a chronobiological basis, cyclic nocturnal TPN is well-tolerated.