肠内营养支持在危重病中的应用研究

目的：观察肠内营养在危重病中的支持效果。方法：将ＩＣＵ中２６例危重患者随机分为肠内营养支持组（１４例）和肠外营养支持组（１２例）,在营养支持前１日及营养支持第１０日测量三头肌皱厚度,上臂肌围,血清白蛋白及血红蛋白,每日计算氮平衡并观察相关并发症情况。     

Enteral nutrition in the critically ill patient: A critical review of the evidence

Objective To examine the relationship between enteral nutrition (EN) and infection in the critically ill.Setting: Computerized search of published research and review of relevant reference lists.Study selection: 151 citations were reviewed and 39 articles met selection criteria. Primary studies were included if they evaluated EN in critically ill humans and its effect on infectious morbidity and mortality.Measurements and results Relevant data were abstracted on the timing and impact of EN on morbidity, the optimal route of administration, composition and pH of EN, and bacterial contamination of EN. The evidence from human studies that EN, particularly early EN, results in reduced septic morbidity as compared to parenteral nutrition is limited to small, unblinded studies with non-rigorous definitions of pneumonia. There is no evidence to support a preference of feeding into the stomach versus the small bowel. The addition of fish oil, arginine, glutamine and fiber to enteral feeds has a variable impact on survival in animal models; there are no trials in critically ill patients that demonstrate a reduction in infectious morbidity and mortality. Acidification of enteral nutrition results in decreased bacterial colonization of the stomach in critically ill patients. Bacterial contamination of enteral nutrition is an important source of infection.Conclusions Evidence from experimental data in critically ill patients suggests that enteral nutrition may have a favourable impact on gastrointestinal immunological function and infectious morbidity.     

高膳食纤维肠内营养改善危重症患者营养状况及耐受

目的 研究高膳食纤维肠内营养对危重症患者营养状况及耐受性的影响.方法 将78例危重症患者随机分成标准肠内营养乳剂组(对照组)和高膳食纤维肠内营养乳剂组(研究组),每组39例.观察肠内营养支持10d后,患者营养状况、胃肠道并发症及耐受性.结果 对照组与研究组各项指标在治疗前均无明显差异(P均＞0.05).与治疗前比较,治...     

危重病患者血清瘦素表达及营养评价指标的作用

目的　探讨危重患者急性期禁食、全胃肠外营养 (TPN)治疗后血清瘦素的表达 ,以及营养评价指标对营养支持的作用。方法　用放射免疫法测定危重病患者血清瘦素 ,同时检测相关营养评价指标。结果　危重病患者急性期瘦素变化不明显 ,TPN治疗后迅速上升 ,第 3天达高峰 ,治疗后 5d仍高于正常。两组血浆纤维蛋白原、白蛋白、总胆固醇、甘油三脂、血淋巴细胞计数差异均无显著性意义 ,P >0 0 5。结论　危重病患者急性期禁食血清瘦素无显著性改变 ,但对TPN治疗反应迅速 ,血清瘦素有可能用来作为危重病患者急性期营养评价指标。血浆纤维蛋白原、白蛋白、总胆固醇、甘油三脂、淋巴细胞计数对危重病患者急性期营养状况无评价性作用。     

Indirect calorimetry measurements in the ventilated critically ill patient: facts and controversies--the heat is on

The provision of nutrition to critically ill patients in the ICU often receives lower priority compared with hemodynamic and ventilation control. This frequently results in a significant calorie deficit. Overestimation of daily energy expenditure may also result in adverse outcomes. In many centers, nutritional decision making is based on predictive formulas, which have been shown to underestimate true energy requirements. Such estimations are ideally performed using indirect calorimetry. Nevertheless, the use of indirect calorimetry has been limited owing to costs and technical difficulties. Controversies about its actual clinical benefits are the focus of recent clinical studies and recommendations. The aim of this review was to describe the advantages of measuring indirect calorimetry within the concept of energy-protein goal-oriented therapy.     

Total parenteral nutrition in critically ill surgical patients: fixed vs tailored caloric replacement

In critically ill patients accurate measurement of total energy expenditure (TEE) is possible by means of continuous indirect calorimetry. Since in many ICUs the necessary equipment is not available, the Harris-Benedict formula (HB) is frequently used to calculate TEE. Supplemental application of a clinical correction factor (HBc) has been advised. In this study we assessed the reliability of both methods of calculation and of a standard nutritional regimen, all three compared to the calorimetrically measured TEE (gold standard). Although the basic HB-formula did not perform better than the standard regimen, significantly better results were obtained by supplemental application of the clinical correction factor (HBc). It is left undecided, whether or not indirect calorimetry is actually to be preferred in daily clinical practice.     

Weight-adjusted resting energy expenditure is not constant in critically ill patients

Objective In critically ill patients, energy requirements are frequently calculated as a multiple of total body weight presuming a linear relationship between total body weight and resting energy expenditure (REE); however, it is doubtful if this estimation of energy needs should be applied to all patients, particularly to overweight patients, since adipose tissue has a low contribution to REE. This study was undertaken to test the hypothesis that REE adjusted for total body weight decreases with increasing body mass index in critically ill patients. Additionally, measured REE was compared with three predictive equations. Design and Setting Clinical study in a university hospital intensive care unit. Patients One hundred critically ill patients admitted to the intensive care unit. Measurements and results Patients were included into four groups according to their body mass index (normal weight, pre-obese, obese, and morbidly obese). Measured REE was assessed using indirect calorimetry. Energy needs were calculated using the basal metabolic rate, the Consensus Statement of the American College of Chest Physicians (REEacs), and 25 kcal/kg of ideal body weight (REEibw). Adjusted REE was 24.8 ± 5.5 kcal/kg in normal weight, 22.0 ± 3.7 kcal/kg in pre-obese, 20.4 ± 2.6 kcal/kg in obese, and 16.3 ± 2.3 kcal/kg in morbidly obese patients (p < 0.01). Basal metabolic rate underestimated measured REE in normal weight and pre-obese patients. REEacs and REEibw over- and underestimated measured REE in overweight patients, respectively. Conclusions Predictive equations were not able to estimate measured REE adequately in all the patients. Adjusted REE decreased with increasing body mass index; thus, a body mass index group-specific adaptation for the estimation of energy needs should be applied.     

The main determinants of nitrogen balance during total parenteral nutrition in critically ill injured patients

Factors influencing nitrogen balance during total parenteral nutrition have been investigated in 34 critically ill injured patients studied during the first 6 days after trauma. Basal nitrogen balance was severely negative (-0.26±0.12 (SD) g·kg^-1), but improved consistently during treatment. Nitrogen intake proved to be the major determinant of a positive, or less negative, nitrogen balance, only secondarily followed by total energy intake corrected to predicted basal energy expenditure, according to multiple regression analysis. The amount of non-protein calories and the non-protein calorie to nitrogen ratio appeared to have little significance on nitrogen balance, when corrected for the two former variables.     

新型冠状病毒肺炎危重症患者营养治疗专家建议

当前抗击新型冠状病毒疫情进入决战阶段,危重症患者的营养治疗是降低病死率的关键措施。为了进一步提高危重症患者的营养治疗效果,现结合抗疫前线的临床经验,就危重症患者的营养代谢特点、营养筛查、营养治疗目标量、营养方案和途径的选择,以及营养监测方法等方面做出总结和建议,为危重症患者的救治提供参考。     

早期不同营养支持方式在机械通气重症患者中的应用

目的探讨早期3种营养支持方式对机械通气重症患者疗效及预后的影响,为临床提供参考。方法选择2009年2月至2011年12月由各种病因所致的行机械通气治疗的重症住院患者90例,按随机数字法随机分为3组,每组各30例,分别予以肠外营养（PN）、肠内营养（EN）、肠内外联合营养（CEPN）支持。检测机械通气第1天、第7天所有患者的营养指标（氮平衡、白蛋白）、免疫指标（IgA、IgG）及血浆内毒素水平,并观察早期并发症发生及治疗情况。结果90例患者早期成功脱离呼吸机57例,死亡25例,出现并发症32例。在机械通气第7天,CEPN组及EN组各项观察指标（氮平衡、自蛋白、IgA、IgG、内毒素水平、并发症例数、脱机数）均优于PN组。PN组：（2．3±1．2）g／d,（30．6±2．7）,（1．4±0．5）,（7．8±2．1）g／L,（37．1±6．3）Pg／ml,17例,13例;EN组：（4．2±0．5）g／d,（33．5±1．8）,（2．5±0．3）,（13．6±1．5）g／L,（49．7±7．3）pg／ml,9例,21例;CEPN组：（5．8±0．8）g／d,（35．8±1．7）,（2．5±0．2）,（13．9±1．7）g／L,（50．3±7．1）pg／ml,6例,23例,差异具有统计学意义（EN组与PN组比较t值分别为－5.158,－2．308,－7．113,－5．031,-2．259;x^2值分别为4．800,6．533;p均〈0．05;CEPN组与PN组比较t值分别为－8．473,－4．201,－6．570,-5．852,-3．141;X^2值分别为9．966,12．448;P均〈0．05）;CEPN组与EN组在营养指标、并发症发生率上的差异具有统计学意义（t值分别为-4．765,-1．169;x^2=4．172;P均〈0．05）。结论对于机械通气的重症患者,早期在尽可能实施EN的基础上,联合适当的PN是一种更为合理有效的营养支持方式,可有效提高患者的综合疗效,减少并发症的发生。     

Impaired gastric emptying in mechanically ventilated,critically ill patients

Objective To measure gastric emptying in critically ill patients using an acetaminophen absorption model and determine which variables are associated with impaired gastric emptying.Design A prospective, cohort study.Setting A medical/surgical ICU at a tertiary care hospital: Hamilton General Hospital, Hamilton, Ontario.Patients and participants We recruited 72 mechanically ventilated patients expected to remain in the ICU for more than 48h. Our results were compared to those in healthy volunteers.Intervention Within 48 h of admission to the ICU, 1.6 g acetaminophen suspension were administered via a nasogastric tube into the stomach. Blood samples were drawn at=0, 30, 60, 90, and 120 min for measurement of plasma acetaminophen levels determined by the enzymatic degradation method.Measurements and results Maximal concentration of acetaminophen was 94.1 (75.3) mol/l compared to 208.4 (33.1) mol/l in a control population (p<0.0001). The time to reach the maximal concentration was 105 min (60–180) compared to 30 min (15–90) in controls (p<0.0001). The area under the time-acetaminophen concentration curvet=120 was 9301 (7343) mol/min per 1 compared to 11644 (1336) mol/min per 1 in the controls (p=0.28). The variables associated with delayed gastric emptying were age, sex and use of opioids for analgesia and sedation.Conclusions Gastric emptying is delayed in critically ill patients. The important consequences of this phenomenon include intolerance to enteral nutrition and gastric colonization. Strategies to minimize the use of narcotics may improve gastric emptying. Studies to examine the effect of gastrointestinal prokinetic agents on gastric emptying are needed.     

Hypophosphatemia in critically ill patients

Purpose

The aim of this study was to assess the association of phosphate concentration with key clinical outcomes in a heterogeneous cohort of critically ill patients.

Materials and Methods

This was a retrospective observational study at a general intensive care unit (ICU) of an Australian university teaching hospital enrolling 2730 adult critically ill patients.

Results

We studied 10?504 phosphate measurements with a mean value of 1.17 mmol/L (measurements every 28.8 hours on average). Hyperphosphatemia (inorganic phosphate [iP] concentration > 1.4 mmol/L) occurred in 45% and hypophosphatemia (iP ≤ 0.6 mmol/L) in 20%. Among patients without any episodes of hyperphosphatemia, patients with at least 1 episode of hypophosphatemia had a higher ICU mortality than those without hypophosphatemia (P = .004). In addition, ICU nonsurvivors had lower minimum phosphate concentrations than did survivors (P = .009). Similar results were seen for hospital mortality. However, on multivariable logistic regression analysis, hypophosphatemia was not independently associated with ICU mortality (adjusted odds ratio, 0.86 [95% confidence interval, 0.66-1.10]; P = .24) and hospital mortality (odds ratio, 0.89 [0.73-1.07]; P = .21). Even when different cutoff points were used for hypophosphatemia (iP ≤ 0.5, 0.4, 0.3, or 0.2 mmol/L), hypophosphatemia was not an independent risk factor for ICU and hospital morality. In addition, timing of onset and duration of hypophosphatemia were not independent risk factor for ICU and hospital mortality.

Conclusions

Hypophosphatemia behaves like a general marker of illness severity and not as an independent predictor of ICU or in-hospital mortality in critically ill patients.     

A retrospective evaluation of nutrition support in relation to clinical outcomes in critically ill patients with an open abdomen

BackgroundOptimising nutrition support in critically ill patients with an open abdomen is challenging.ObjectivesThe aims of this study were to (i) quantify the amount and adequacy of nutrition support administered and (ii) determine any relationships that exist between mode of nutrition support delivery and clinical outcomes in critically ill patients with an open abdomen.MethodsA retrospective review of critically ill patients mechanically ventilated for at least 48 h with an open abdomen in a mixed quaternary referral intensive care unit. Enteral and parenteral nutrition (ml) administered daily to patients was recorded for up to 21 days. Length of stay in the intensive care unit and hospital and duration of mechanical ventilation (days) were reported.ResultsThirty patients were studied [14 male, 68 y (15–90 y), body mass index 25 kg/m² (11–51 kg/m²), Acute Physiology and Chronic Health Evaluation II score 20 (7–41), energy goal 1860 kcal/d (1250–2712 kcal/d)]. Patients received 55% (0–117%) of energy goal and 56% (0–105%) protein goal from either enteral or parenteral nutrition. When enteral nutrition was delivered alone or in combination with parenteral nutrition, patients received 48% (0–146%) of their energy and 59% (19–105%) of their protein goal. Patients fed parenteral nutrition, either alone or as supplementary to enteral nutrition (n = 18), received more energy when compared with those who only received enteral nutrition (n = 9) [65 (27–117) vs 49 (15–89) % energy goal, P = 0.025]. Parenteral nutrition was associated with an increased length of stay in hospital [63 (45–156) vs 45 (17–93) d, P = 0.037].ConclusionPatients with an open abdomen receive about half of their nutrition requirements when fed exclusively via the enteral route. Providing combination enteral and parenteral nutrition to reach nutritional goals may not result in better clinical outcomes for patients with an open abdomen.     

Parenteral with enteral nutrition in the critically ill

Objective: To determine whether nutrient intake by early enteral nutrition with parenteral nutrition improves levels of retinol-binding protein and prealbumin (primary endpoint) and reduce morbidity and mortality (secondary endpoint) in ICU patients. Design: Prospective, double-blind, and randomized, placebo-controlled study. Setting: Two intensive care units in a tertiary institution. Patients and participants: 120 patients in two groups of 60.¶Interventions: Patients received either enteral plus parenteral nutrition (treatment group) or enteral nutrition plus placebo (placebo group) for 4–7 days after initiation of nutritional support. Measurements and results: Retinol-binding protein (P = 0.0496) and prealbumin (P = 0.0369) increased significantly in the treatment group from day 0 to day 7. There was no reduction in morbidity in ICU. There was no difference in OMEGA score (263 vs. 244) and length of stay in the ICU (16.9 vs. 17.3), but a reduction in length of stay at hospital (31.2 ± 18.5 vs. 33.7 ± 27.7, P = 0.0022). Mortality on day 90 (17 vs. 18) and after 2 years (24 vs. 24) was identical. Conclusions: Although it enhances nutrient intake and corrects nutritional parameters such as RBP and prealbumin more rapidly, within 1 week, supplemental parenteral nutrition has no clinically relevant effect on outcome in ICU patients at the early phase of nutritional support.     

Monitoring nutritional status in the critically ill adult

Nutritional support is an important aspect of the multidisciplinary approach to critical care medicine. During stress, visceral protein turnover is increased. However, muscle and connective tissue proteolysis is obligatory if the stressful condition persists. Through nutritional support, peripheral protein breakdown is minimized and visceral protein synthesis maximized. A delivery system of 15% to 20% dietary protein, 30% fat, 50% to 55% carbohydrate, complemented by moderate amounts of vitamins and minerals, is considered best. Optimal nutritional care depends on objective assessment of the patient's nutritional status before and during nutritional support, particularly the nutritional status of the body cell mass and the energy required for maintenance and support of reparative processes. Indicators least disturbed by factors should be selected for assessment. Individual indicators vary in critical states. After resuscitation, excess body water may increase body weight; after surgery, stress may depress albumin levels. Biometric markers of nutritional status and measurements that adequately validate and evaluate response to nutritional support are discussed.     

Glycemic control in critically ill patients

Hyperglycemia is common in critically ill patients and can be caused by various mechanisms, including nutrition, medications, and insufficient insulin. In the past, hyperglycemia was thought to be an adaptive response to stress, but hyperglycemia is no longer considered a benign condition in patients with critical illnesses. Indeed, hyperglycemia can increase morbidity and mortality in critically ill patients. Correction of hyperglycemia may improve clinical outcomes. To date, a definite answer with regard to glucose management in general intensive care unit patients, including treatment thresholds and glucose target is undetermined. Meta-analyses of randomized controlled trials suggested no survival benefit of tight glycemic control and a significantly increased incidence of hypoglycemia. Studies have shown a J- or U-shaped relationship between average glucose values and mortality; maintaining glucose levels between 100 and 150 mg/dL was likely to be associated with the lowest mortality rates. Recent studies have shown glycemic control < 180 mg/dL is not inferior to near-normal glycemia in critically ill patients and is clearly safer. Glycemic variability is also an important aspect of glucose management in the critically ill patients. Higher glycemic variability may increase the mortality rate, even in patients with the same mean glucose level. Decreasing glucose variability is an important issue for glycemic control in critically ill patients. Continuous measurements with automatic closed-loop systems could be considered to ensure that blood glucose levels are controlled within a specific range and with minimal variability.     

Venous thromboembolism prophylaxis in critically ill patients

Venous thromboembolism (VTE) is a frequent but often silent complication of critical illness that has a negative impact on patient outcomes. The prevention of VTE is an essential component of patient care in the intensive care unit (ICU) setting, and is the focus of this article. The use of anticoagulant thromboprophylaxis significantly decreases the risk of VTE in ICU patients and is discussed at length.     

参附注射液在危重症患者中的应用进展

参附注射液是我国传统医学和现代医学融合发展的结晶,随着近些年对其作用机制的不断探索及临床研究的逐渐深入,其适用范围不断拓展,尤其在救治急危重症患者中的有效性和安全性不断得到肯定,日益受到学者们的关注。本文就参附注射液的作用机制以及在危重症患者,特别是休克及心肺复苏患者中的应用进行综述,以期对将来基础医学和临床研究有所帮助。     

肠内外营养对危重患者脏器功能影响的对比研究

目的探讨肠内外营养支持治疗对危重肺部感染患者内脏功能的保护作用。方法将42例重症监护室（ICU）重症肺部感染患者随机分为肠内营养（EN）组、静脉营养组和对照组，每组14例。给予相应治疗后7d观察患者血清丙氨酸转氨酶（ALT）、动脉血氧分压（PaO2）、动脉血二氧化碳分压（PaCO2）、血尿素氮（BUN）、白细胞计数（WBC）的变化及消化道出血发生率。结果对照组ALT、WBC均明显高于EN组和静脉营养组，PaO2明显低于EN组和静脉营养组（P均〈0．05）；EN组和静脉营养组间的ALT、WBC及PaO2差异均无显著性。对照组和静脉营养组消化道出血发生率均为42．9％，明显高于EN组的21．4％（P均〈0．05）。3组患者血BUN及PaCO2则无明显变化（P均〉0．05）。结论重症肺部感染患者及早给予EN比静脉营养和单纯葡萄糖供能要优越得多，有助于保护胃肠道和其他重要器官功能，防止肠道细菌及毒素移位，减轻全身炎症反应，防止多脏器功能不全发生。