高能低糖肠内营养液改善机械通气COPD患者的临床疗效

目的观察高脂肪(50%)、低碳水化合物(32%)肠内营养液对机械通气慢性阻塞性肺疾病(COPD)患者的临床疗效。方法我院32例机械通气COPD患者,平均年龄(70.4±17.4)岁,体重为(45.4±6.6)kg,均明显低于正常值(P<0.01);并伴有明显的营养不良。随机分为高能低糖肠内营养组(n=18)和传统肠内营养组(n=14)。两组均采用鼻饲肠内营养支持,每天供给热能125kJ(30kcal)/kg,蛋白质0.8~1.0g/kg,热氮比值为627.6kJ比1g。分别于营养治疗前一天及治疗后第10天测定血常规、电解质、呼吸商(RQ)、每分钟通气量(VE)、二氧化碳生成量(VCO2)、氧耗量(VO2)、二氧化碳分压(PaCO2)、氧分压(PaO2)、pH值以及血清总蛋白、白蛋白、血红蛋白、淋巴细胞比例等指标。结果治疗前两组患者的各项指标测定值相近,治疗10天后高能低糖组患者的VE、VCO2、VO2、RQ均较传统营养组显著降低(P<0.05)。传统营养治疗前后VE、VCO2、VO2、RQ无明显变化。两组患者的血气分析均有不同改善,高能低糖肠内营养组的PaCO2较传统肠内营养组降低,PaO2增高,但两组的差异无显著性。两组血液生化和血常规结果均无显著差异。结论高能低糖营养制剂能降低VCO2和RQ,减少VE和VO2,对于失偿期COPD患者有明显的临床治疗效果。     

肺病专用低糖类营养配方对呼吸衰竭病人的影响

目的:评价肺病专用低糖类营养配方(益菲佳)对呼吸衰竭病人的影响.方法:将60例符合入选标准的病人随机分为研究组和对照组,研究组给予益菲佳,对照组给予均衡经肠营养制剂(安素).于治疗前后分别检测病人的血脂、血清蛋白质和二氧化碳分压(PaCO2)、氧分压(PaO2)、氧耗量(VO2)、二氧化碳生成量(VCO2)和呼吸商(RQ)等指标,以评价其营养支持效果.结果:经过10天的营养治疗,研究组的血气分析指标与治疗前相比有显著性差异(P＜O.05或P＜0.01),而且与对照组同期相比也有显著性差异(P＜0.05或P＜0.01).结论:益菲佳能降低机械通气病人的VO2、VCO2、PaCO2和RQ,对改善呼吸衰竭病人的肺功能和营养状态具有一定的作用.     

肺动脉高压对COPD患者运动耐力及通气有效性的影响

目的探讨分析肺动脉高压对COPD患者运动耐力及通气有效性的影响。方法随机选取收治的慢阻肺合并呼吸衰竭患者100例,按多普勒超声心动图肺动脉收缩压﹥30mm Hg分成两组,对照组45例,无肺动脉高压。观察组55例,伴肺动脉高压。对全部患者进行肺功能检测、超声心动图检测、症状限制性心肺运动试验。结果观察组患者的VE/VCO2slope、lowest VE/VCO2、AT-VE/VCO2、peak VO2/%pred均明显低于对照组,差异有统计学意义(P﹤0.05)。结论肺动脉高压会导致COPD患者运动耐力及通气有效性下降。     

高能低糖营养液在COPD机械通气病人营养支持中的疗效观察

目的:探讨慢性阻塞性肺疾病(COPD)并发呼吸衰竭病人机械通气时,早期应用高能低糖肠内营养对病人治疗效果的影响。方法:将40例病人随机分为试验组(使用高能低糖肠内营养液)和对照组(使用普通肠内营养液),治疗10d。比较两组病人每分钟通气量(VE),二氧化碳生成量(VCO2),动脉血二氧化碳分压(PaCO2),机械通气时间,血清清蛋白,免疫球蛋白,总淋巴细胞计数等。结果:治疗后,试验组病人的PaCO2、VCO2与对照组相比有明显改善(P0.05);机械通气时间亦短于对照组(P0.05)。两组病人的血清清蛋白、免疫球蛋白和淋巴细胞计数等无显著性差异(P0.05)。结论:COPD机械通气病人,尽早合理地应用高能低糖肠内营养支持治疗,能有效地减少病人CO生成量,降低呼吸商,缩短机械通气时间,提高综合治疗的疗效。     

继续教育园地·健康生活方式管理系列讲座第2期思考题答案

一、糖尿病生活方式管理的主要内容有哪些？ 1．合理的营养与膳食指导：（1）合理控制总能量：控制总能量是糖尿病膳食治疗的首要原则，能量的摄入以能够维持理想体重或略低于理想体重为宜。理想体重=22×身高（m）^2。总能量的摄入=理想体重×生活强度。（2）合理分配碳水化合物、脂肪、蛋白质的比例，尽量做到平衡膳食。碳水化合物、脂肪、蛋白质占总能量的比例分别为60％、25％和15％。     

急性冠状动脉综合征患者PCI后及随访期运动试验心脏功能的评价

目的通过运动负荷试验评价经皮冠状动脉介入治疗（PCI）效果,为患者进一步康复提供参考。方法对行常规PCI的36例急性冠状动脉综合征患者分别于PCI前后1周及随访期行亚极量平板运动试验,监测血压、心率、心电图变化及最大氧耗量（VO2max）等参数。结果PCI后运动所达到的最大心率（HRmax）较术前明显提高（143.1比135.1次/min,P〈0.05）,最大运动量明显提高（7.11比6.53mETS,P〈0.01）,运动诱发的心电图相应导联S-T段压低明显改善（-1.39比-0.85mm,P〈0.002）,运动中每分钟通气量（VE）、二氧化碳的产生（VCO2）均明显增加（分别为55.7比51.0L/min,P〈0.02及1.87比1.76L/min,P〈0.02）。与术后比较,随访期运动时间、最大运动量、VE、VCO2及VO2均有明显提高（分别P〈0.005,P〈0.02）。结论急性冠状动脉综合征患者PCI后VO2max、HRmax、VE及VCO2均明显提高,运动诱发的心肌缺血明显改善,运动耐量明显增加。     

膳食宏量营养素与血脂对妊娠期糖尿病的影响

目的 探讨膳食宏量营养素与血脂对妊娠期糖尿病发病的影响。方法 选择中期妊娠诊断为妊娠期糖尿病的孕妇47例（GDM组）,正常孕妇58例（正常妊娠组）为调查对象,进行24 h回顾性膳食调查,并比较2组孕妇膳食结构中宏量营养素每日摄入量及血清中甘油三酯和总胆固醇的变化。结果 糖尿病组孕妇每日摄入总热卡,碳水化合物、脂肪和蛋白质摄入量以及总胆固醇和甘油三酯均高于正常妊娠组。结论 孕前体重指数高、孕妇摄入碳水化合物、脂肪和蛋白质过多,血甘油三酯和总胆固醇上升,可能是妊娠期糖尿病发病的原因之一。     

慢性重型肝炎患者碳水化合物、蛋白质、脂肪氧化代谢监测

目的探讨慢性重型肝炎患者碳水化合物、蛋白质、脂肪氧化供能的特点。方法采用间接测热法应用CCM/D营养代谢测试系统测定8例慢性重型肝炎患者夜间禁食与睡前加餐后晨起空腹及3餐后2小时的呼吸商(RQ)及24小时尿氮(微量凯式定氮法),监测静脉应用葡萄糖时的RQ。结果慢性重型肝炎患者夜间禁食晨起空腹时RQ为全天中最低(0.76±0.07),脂肪、蛋白质、碳水化合物氧化率依次为(63.88±31.60)%、(22.38±13.19)%、(13.75±23.64)%;睡前加餐RQ均提高,脂肪氧化率降低到(48.13±28.24)%,碳水化合物氧化率增加到(37.25±24.05)%,蛋白质氧化率降低到(14.75±10.73)%;静脉应用葡萄糖时可见RQ迅速提高。结论慢性重型肝炎患者晨起空腹时以脂肪、蛋白质为主要供能物质,睡前加餐及葡萄糖的静脉应用可提高碳水化合物的供能比例,节约脂肪、蛋白质。     

癌症患者的营养平衡

碳水化合物：食物主要的能量来源是碳水化合物（糖），占一天食物热量的55％～60％，当食物中碳水化合物不足时，机体中的蛋白质和脂肪就成了能量的来源。     

稳定期慢性阻塞性肺疾病和肺心病患者营养状况分析

目的 通过对稳定期COPD和肺心病患营养状况的分析，为开展有针对性的饮食干预治疗提供参考依据。方法 采用24h膳食回忆法，并进行营养测量、生化检验和肺通气功能检查，及其与营养指标的相关性分析。结果 88名患热能和蛋白质、脂肪等营养素的摄入明显不足；碳水化合物摄入偏高。21．59％体重偏低。营养及生化指标均与肺通气功能存在不同程度的正相关。纬论 热能和多种营养素的摄入不足是导致营养不良的重要原因之一。     

Energy expenditure and substrate utilization in mechanically ventilated children.

The objective of the study was to determine the value of indirect calorimetry and nitrogen balance (N balance) in order to evaluate the current feeding protocols of mechanically ventilated children. The study was designed as a cross-sectional prospective study. In 36 mechanically ventilated children energy expenditure was measured by indirect calorimetry, and total urinary nitrogen excretion (TUN) was determined. Substrate utilization and respiratory quotient (RQ) were calculated from the measured values of oxygen consumption (VO2), carbon dioxide production (VCO2), and TUN. The RQ was compared with the RQ of the macronutrients administered (RQmacr) according to the modified criteria of Lusk. In results, the total measured energy expenditure (TMEE) showed a wide variation (range 155-272 kJ.kg-1.d-1). The N balance was positive in 20 and negative in 16 patients. The ratio of caloric intake/TMEE was significantly higher in patients with a positive N balance (1.50 +/- 0.06) as compared with those with a negative N balance (0.8 +/- 0.1, P < 0.001). There was a significant relationship between the difference of RQ-RQmacr versus the ratio caloric intake/TMEE (r = 0.72, P < 0.001). Carbohydrate and fat utilization were not significantly different in patients with a positive or negative N balance. Protein utilization was significantly higher in those patients with a negative N balance. We concluded that measurement of TMEE with indirect calorimetry results in accurate determination of energy needs in critically ill mechanically ventilated children. Feeding according to or in excess of the TMEE is correlated with a positive N balance. A combination of the RQ and the RQmacr can be helpful in differentiating under- or overfeeding.     

Effects of dietary protein content on weaning from the ventilator

The effect of enteral nutrition with different protein contents on metabolic and ventilatory variables during weaning from the ventilator was studied in 10 mechanically ventilated patients as indication of the effect of protein on the ventilatory drive. Resting energy expenditure (R.E.E.) was assessed in the post-absorptive state and 2 enteral regimens both with a fat and carbohydrate content 1.25 times R.E.E. but with a moderate (190 mg N/kg/24 h) and high (260 mgN/kg/24 h) protein content were given to the patients in random order. Minute ventilation (V(E)), CO(2)-production (VCO(2)), O(2)-consumption (VO(2)) and arterial blood-gases were obtained during mechanical ventilation and weaning. Compared with post-absorptive state, both intakes gave significant increases in VCO(2) during mechanical ventilation; the VCO(2) values were equal for both regimens before the start of the weaning procedures. High protein intake was associated with significantly higher VCO(2) during weaning and smaller increases in p(a)CO(2) from mechanical ventilation to the end of the weaning-period, compared with the moderate protein intake. This result is in agreement with studies in which an infusion of amino-acids in spontaneous breathing healthy volunteers increased ventilatory sensitivity to CO(2). For mechanically ventilated patients high protein nutrition may be beneficial in enhancing weaning from the ventilator.     

Clinical use of the respiratory quotient obtained from indirect calorimetry

BACKGROUND: The respiratory quotient (RQ) obtained from indirect calorimetry (IC), defined by the ratio carbon dioxide production (VCO2)/oxygen consumption (VO2), is affected by extremes of substrate use by the body. Underfeeding, which promotes use of endogenous fat stores, should cause decreases in the RQ, whereas overfeeding, which results in lipogenesis, should cause increases in the RQ. Marked increases in VCO2 (with subsequent increases in RQ) in response to overfeeding may cause respiratory compromise in patients with limited pulmonary reserve. Thus, variation in the RQ in response to the feeding regimen may indicate inappropriate feeding and serve as a marker for patient intolerance. This prospective, multicenter study was designed to determine the clinical use of RQ for monitoring adequacy and tolerance of nutrition support. METHODS: Patients in any 1 of 30 long-term acute care Kindred hospitals made nil orally (NPO) and placed on total parenteral or enteral feeding were eligible for this study. Arterial blood gas, serum ketones, 24-hour collection of urine urea nitrogen, and IC measurements were obtained on all. Actual volume of enteral/parenteral feeding infused over the 24 hours before performance of IC was documented. RESULTS: A total of 263 patients (mean age, 70.2 years, 57.4% male) were entered in the study. Of the 263 study patients, 88.6% required mechanical ventilation, and 92.0% received enteral tube feeding only. Overall, 41.5% of patients were overfed, receiving >110% of required calories, whereas 34.2% were underfed, receiving <90% of required calories. The ratio of calories provided/required correlated significantly with overall measured RQ (p < .0001; R2 = .16). Correcting for the metabolism of protein by calculating a nonprotein RQ (NPRQ) from a 24-hour urine urea nitrogen did not improve this correlation (p < .0001, R2 = .32). Using a measured NPRQ >1.0 to identify overfeeding had an acceptable specificity of 85.1% but a low sensitivity of 38.5%. Similarly, use of a NPRQ <0.85 to determine underfeeding had a specificity of 72.2% and a sensitivity of 55.8%. Comparing the measured NPRQ with a predicted reference RQ (based on percent infusion of carbohydrate/fat and the Lusk table) did not improve the overall use of RQ. In the majority of patients (67.7%), comparison of the measured NPRQ to the predicted value failed to differentiate appropriate (meeting 100% +/- 10% of requirements) from inappropriate feeding. Deviation of the measured NPRQ from predicted failed to identify factors unrelated to substrate use purported to affect the RQ (such as acid/base disturbances or hyper/hypoventilation). Increasing measured RQ did correlate significantly with increasing respiratory rate (p = .002, R2 = .04) and decreasing tidal volume (p = .002, R2 = .04), suggesting reduced tolerance with development of shallow rapid respirations and ventilatory compromise. CONCLUSIONS: Although changes in the overall and nonprotein RQ correlate to percent calories provided/required, low sensitivity and specificity limit its efficacy as an indicator of over- or underfeeding. The RQ should not be used to finely adjust the nutrition support regimen. Elevation of overall measured RQ > or = 1.0 may be associated with reduced tolerance and mild respiratory compromise. The clinical use of RQ is limited to a marker of test validity (to confirm measured RQ values are in physiologic range) and a marker for respiratory tolerance of the nutrition support regimen.     

高脂低糖肠内营养制剂对ICU机械通气病人营养及肺部功能影响的研究

目的:观察高脂低糖肠内营养制剂对ICU机械通气病人的营养以及肺部功能的影响。方法:将271例病人随机分为试验组和对照组,分别给予高能低糖肠内营养制剂和通用型肠内营养配方制剂,观察病人治疗前后前白蛋白、白蛋白、血气分析、IgG、CD4、CD4/CD8、机械通气时间等指标。结果:经过营养支持治疗,两组前白蛋白、白蛋白均明显改善,两组间无明显差异;两组血气分析、IgG、CD4、CD4/CD8、营养费用、机械通气时间等均明显改善,且试验组优于对照组。结论:高脂低糖肠内营养制剂可以改善ICU机械通气病人的营养状态和肺部功能,可以缩短机械通气时间、节约医疗费用,是一种理想的肠内营养制剂。     

A validation and comparison study of two metabolic monitors

Two portable metabolic cart systems of indirect calorimetry (Deltatrac Metabolic Monitor, 2900 MMC System) were validated. CO2 and N2 were delivered at precise rates into a constructed lung model to simulate CO2 production (VCO2) and O2 consumption (VO2). VCO2 (200-400 ml/min) and VO2 (250-750 ml/min) were measured at varying combinations of minute ventilation (VE) (6, 10, 20 liter/min) and FiO2 (0.21, 0.30, 0.60, 0.80). VCO2 was measured with overall errors of 1.5% and 2.4% for the Deltatrac and 2900 monitors, respectively. VO2 was measured with overall errors of 1.9% and 3.2% by the Deltatrac and 2900 monitors, respectively. Both monitors performed equally well for measurement of VO2 at FiO2 up to 0.6, but the Deltatrac had less error for measurements of VO2 at FiO2 of 0.8.     

Tissue uptake and oxidation of disodium sebacate in man

In order to better ascertain its possible use as an alternative fuel substrate in total parenteral nutrition, sebacate (Sb) metabolism was studied in seven overnight-fasting healthy male volunteers, who received a constant iv infusion (99 mmoles over 8 hours) of disodium sebacate. Sb oxidation rate was determined using an isotopic sebacate (disodic salt of (1-10)14C-sebacic acid) infusion (100 mu Ci from the fourth to the eighth hour of the cold sebacate infusion). Blood samples were collected during and after sebacate infusion at intervals of 30 minutes and Sb serum concentrations were determined by high performance liquid chromatography. Excreted radioactivity (mu Ci/min) was measured by bubbling the expired air into an apparatus containing 3 mEq hyamine to trap CO2 from a 20-L Douglas-bag. CO2 production and O2 consumption were measured before and at 4 and 8 hours after starting the infusion. Twenty-four hour nitrogen excretion with urine was obtained. The RQ and the percent of calories derived from lipid oxidation were calculated by indirect calorimetry. The Sb serum level at the plateau phase was (mean +/- SD) 4.54 +/- 0.71 mumole/mL, the overall rate of tissue uptake was 180.89 +/- 4.50 mumole/min, and the percent oxidation was 6.14 +/- 0.44%. At the end of Sb infusion the RQ dropped to 0.839 +/- 0.043, the percent of calories due to sebacate oxidation was 1.59 +/- 0.52%, and the calories derived from lipids increased to 37.77 +/- 12.90%. These data show that a definite amount of the sebacate infused is oxidized in human tissues.     

Caloric Requirements of Patients With Brain Impairment and Cerebral Palsy Who Are Dependent on Chronic Ventilation

Background and Objective: Israeli law mandates chronic ventilator support for children and adolescents who are severely brain impaired and show minimal responses. Feeding protocols in these cases have been based on the caloric requirements of healthy children, deducting calories for lack of activity as well as an individual adjustment according to the cerebral palsy growth curves. However, patients are still inclined to gain excessive weight. Our objective was to determine the caloric requirements of these patients. Design and Method: Sixteen patients hospitalized in a dedicated unit who were ventilated through tracheostomies and fed via gastrostomies were included. Patients were aged 3–24 years; duration of ventilation was 1–7.5 years; and diagnoses included congenital genetic or brain malformations (n = 9), hypoxic accidents (n = 4), and postbacterial or postviral encephalitis (n = 3). Resting energy expenditure (REE) was determined by indirect calorimetry. REE values were compared with the caloric requirements of age‐comparable healthy children and the calories actually delivered. Data were analyzed with paired t tests, Pearson correlations, and linear regression. Results: The REE of our patients was 46% lower than the estimated caloric requirements of healthy children. In practice, patients received 32% more calories than that measured by REE. These findings were not affected by age, weight, diagnosis, or length of hospitalization. Conclusions: The caloric expenditure of these patients is very low. A diet guided by indirect calorimetry is proposed to aid in providing optimal nutrition support for this unique population to avoid overfeeding and obesity.