Nielsen K, Kondrup J, Martinsen L, Døssing H, Larsson B, Stilling B, Jensen M G
Department of Medicine A-2152, Rigshospitalet, Denmark.
Br J Nutr. 1995 Oct;74(4):557-67. doi: 10.1079/bjn19950158.
A previous study has shown that malnourished, clinically stable patients with liver cirrhosis are in protein and energy balance at their spontaneous dietary intake and that an improvement in nutritional status cannot be anticipated at this intake (Nielsen et al. 1993). In the present study we examined to what extent oral intake could be increased by nutritional support, and to what extent dietary protein would be retained with increased intake. The techniques used for balance studies were also validated since this information is not available for patients with liver cirrhosis. Fifteen malnourished patients with alcoholic liver cirrhosis were given increasing amounts of a balanced ordinary diet for 38 (SE 3) d. Intakes of protein and energy were recorded by weighing servings and leftovers on food trays. Protein intake was calculated from food tables. Total N disposal was calculated after measurement of urinary N excretion, and protein balance was calculated from the N balance. A validation study of protein balance in a subgroup of patients (analysis of N in food by the duplicate portion technique, correction for incomplete recovery of urine by measurement of urinary para-aminobenzoic acid (PABA) after administration of PABA tablets, and measurement of faecal N) did not change protein balance values. Protein intake increased from 1.0 (SE 0.1) g/kg per d to 1.8 (SE 0.1) g/kg per d. With increasing protein intake, 84 (SE 8)% of the increase in intake was retained. The rate of protein retention was not saturated at the intakes obtained in this study. Protein intolerance was only encountered in one patient. Available evidence indicates that the requirement for achieving N balance is increased in these patients but protein retention is highly efficient with increased intake. Protein retention is dependent on energy balance. Energy intake was calculated from food tables and total energy expenditure was calculated by the factorial method. A validation study was performed in a subgroup of patients. The energy contents of food sampled by the duplicate portion technique, and of urine and faeces were measured by bomb calorimetry. Resting energy expenditure (REE) was measured by indirect calorimetry before and at the end of the study, and O2 uptake during bicycle exercise was measured before and at the end of the study. The measured intake of metabolizable energy was on average 13% lower than the value given in food tables. Calculated energy expenditure was not changed by the validation study.(ABSTRACT TRUNCATED AT 250 WORDS)
先前的一项研究表明,营养不良但临床稳定的肝硬化患者在自发饮食摄入情况下处于蛋白质和能量平衡状态,且按此摄入量无法预期营养状况会得到改善(尼尔森等人,1993年)。在本研究中,我们探究了营养支持能在多大程度上增加口服摄入量,以及随着摄入量增加,膳食蛋白质会在多大程度上被保留。由于肝硬化患者尚无此类信息,我们还对平衡研究中使用的技术进行了验证。15名营养不良的酒精性肝硬化患者接受了逐渐增加量的均衡普通饮食,为期38(标准误3)天。通过称量餐盘上的食物份量和剩余食物来记录蛋白质和能量摄入量。蛋白质摄入量根据食物成分表计算得出。在测量尿氮排泄量后计算总氮排出量,并根据氮平衡计算蛋白质平衡。对一组患者进行的蛋白质平衡验证研究(通过双份食物技术分析食物中的氮,服用对氨基苯甲酸(PABA)片剂后通过测量尿中PABA来校正尿氮不完全回收情况,并测量粪便氮)并未改变蛋白质平衡值。蛋白质摄入量从每天1.0(标准误0.1)克/千克增加到1.8(标准误0.1)克/千克。随着蛋白质摄入量增加,摄入量增加部分的84(标准误8)%被保留。在本研究获得的摄入量水平下,蛋白质保留率未达到饱和。仅1名患者出现蛋白质不耐受情况。现有证据表明,这些患者实现氮平衡的需求量增加,但随着摄入量增加,蛋白质保留效率很高。蛋白质保留取决于能量平衡。能量摄入量根据食物成分表计算得出,总能量消耗通过因子法计算。对一组患者进行了验证研究。通过双份食物技术采集的食物、尿液和粪便的能量含量通过弹式量热法测量。在研究开始前和结束时通过间接量热法测量静息能量消耗(REE),并在研究开始前和结束时测量自行车运动期间的耗氧量。测得的可代谢能量摄入量平均比食物成分表给出的值低13%。验证研究未改变计算得出的能量消耗。(摘要截取自250词)