Protein Requirements in the Critically Ill

Background: Current recommendations for higher protein/amino acid provision in the critically ill are based on weak evidence. This double‐blinded randomized controlled trial aimed to compare standard amino acid intake with the higher level recommended as the minimum for critically ill patients. Methods: In total, 119 patients requiring parenteral nutrition (PN) in an intensive care unit (ICU) were randomized to receive blinded PN solutions containing amino acids at either 0.8 g/kg or 1.2 g/kg. Primary outcome was handgrip strength at ICU discharge. Secondary outcomes measured at study day 7 included handgrip strength, fatigue score (using the Chalder scale), and ultrasound measurements of muscle thickness at defined body sites. Analysis of covariance was used to control for age, sex, nutrition status (Subjective Global Assessment), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and baseline measurement. Results: Actual amino acid delivery to the 2 groups was 0.9 and 1.1 g/kg respectively, averaged over the first 7 days. Grip strength at ICU discharge was not significantly different between groups (P = .054) despite being improved at study day 7 in the group receiving the higher level of amino acids (mean [SD], 22.1 [10.1] vs 18.5 [11.8] kg, P = .025). These patients also had less fatigue (Chalder score, mean [SD], 5.4 [2.2] vs 6.2 [2.2], P = .045) and greater forearm muscle thickness on ultrasound (mean [SD], 3.2 [0.4] vs 2.8 [0.4] cm, P < .0001). Nitrogen balance was significantly better at study day 3 but not at day 7. There was no difference between groups in mortality or length‐of‐stay measures. Conclusion: The higher level of amino acids was associated with small improvements in a number of different measures, supporting guideline recommendations for ICU patients. This trial was registered at Australian New Zealand Clinical Trials Registry ( www.anzctr.org.au ) as ACTRN12609000366257.     

Diarrhea in Critically Ill Patients

This tutorial presents a systematic approach to the management of diarrhea in the critical care setting. Diarrhea is a common and prevalent problem in critically ill patients. Despite the high prevalence, its management is far from simple. Professionals are confronted with a myriad of definitions based on frequency, consistency, and volume. The causes are complex and multifactorial, yet enteral tube feeding formula is believed to be the perpetrator. Potential causes for diarrhea are discussed, and 3 case reports provide context to examine the treatment from a nutrition perspective. Each scenario is comprehensively addressed discussing potential causes and providing specific clinical strategies contributing to improved bowel function in this patient group. The approach used for diarrhea management is based on a complete understanding of enteral tube formula, their composition, and their impact in the presence of gut dysfunction. Choosing the right feeding formula may positively influence bowel function and contribute to improved nutrition.     

Glutamine and Antioxidants in the Critically Ill Patient

Background: The recent large randomized controlled trial of glutamine and antioxidant supplementation suggested that high‐dose glutamine is associated with increased mortality in critically ill patients with multiorgan failure. The objectives of the present analyses were to reevaluate the effect of supplementation after controlling for baseline covariates and to identify potentially important subgroup effects. Materials and Methods: This study was a post hoc analysis of a prospective factorial 2 × 2 randomized trial conducted in 40 intensive care units in North America and Europe. In total, 1223 mechanically ventilated adult patients with multiorgan failure were randomized to receive glutamine, antioxidants, both glutamine and antioxidants, or placebo administered separate from artificial nutrition. We compared each of the 3 active treatment arms (glutamine alone, antioxidants alone, and glutamine + antioxidants) with placebo on 28‐day mortality. Post hoc, treatment effects were examined within subgroups defined by baseline patient characteristics. Logistic regression was used to estimate treatment effects within subgroups after adjustment for baseline covariates and to identify treatment‐by‐subgroup interactions (effect modification). Results: The 28‐day mortality rates in the placebo, glutamine, antioxidant, and combination arms were 25%, 32%, 29%, and 33%, respectively. After adjusting for prespecified baseline covariates, the adjusted odds ratio of 28‐day mortality vs placebo was 1.5 (95% confidence interval, 1.0–2.1, P = .05), 1.2 (0.8–1.8, P = .40), and 1.4 (0.9–2.0, P = .09) for glutamine, antioxidant, and glutamine plus antioxidant arms, respectively. In the post hoc subgroup analysis, both glutamine and antioxidants appeared most harmful in patients with baseline renal dysfunction. No subgroups suggested reduced mortality with supplements. Conclusions: After adjustment for baseline covariates, early provision of high‐dose glutamine administered separately from artificial nutrition was not beneficial and may be associated with increased mortality in critically ill patients with multiorgan failure. For both glutamine and antioxidants, the greatest potential for harm was observed in patients with multiorgan failure that included renal dysfunction upon study enrollment.     

Gastric Emptying in Critically Ill Children

Background: Delayed gastric emptying (GE) impedes enteral nutrient (EN) delivery in critically ill children. We examined the correlation between (a) bedside EN intolerance assessments, including gastric residual volume (GRV); (b) delayed GE; and (c) delayed EN advancement. Materials and Methods: We prospectively enrolled patients ≥1 year of age, eligible for gastric EN and without contraindications to acetaminophen. Gastric emptying was determined by the acetaminophen absorption test, specifically the area under the curve at 60 minutes (AUC₆₀). Slow EN advancement was defined as delivery of <50% of the prescribed EN 48 hours after study initiation. EN intolerance assessments (GRV, abdominal distension, emesis, loose stools, abdominal discomfort) were recorded. Results: We enrolled 20 patients, median 11 years (4.4–15.5), 50% male. Sixteen (80%) patients had delayed GE (AUC₆₀ <600 mcg·min/mL) and 7 (35%) had slow EN advancement. Median GRV (mL/kg) for patients with delayed vs normal GE was 0.43 (0.113–2.188) vs 0.89 (0.06–1.91), P = .9635. Patients with slow vs rapid EN advancement had median GRV (mL/kg) of 1.02 mL/kg (0.20–3.20) vs 0.27 mL/kg (0.06–1.62), P = .3114, and frequency of altered EN intolerance assessments of 3/7 (42.9%) vs 5/13 (38.5%), P = 1. Median AUC₆₀ for patients with slow vs rapid EN advancement was 91.74 mcg·min/mL (53.52–143.1) vs 449.5 mcg·min/mL (173.2–786.5), P = .0012. Conclusions: A majority of our study cohort had delayed GE. Bedside EN intolerance assessments, particularly GRV, did not predict delayed GE or rate of EN advancement. Delayed gastric emptying predicted slow EN advancement. Novel tests for delayed GE and EN intolerance are needed.     

A New Look at the Critically Ill

Many therapeutic modalities are now available that can not only reduce mortality among high-risk neonates, especially the premature, but diminish the threat of lasting neurologic damage among those who survive. These resources can be applied most effectively through the newborn special or intensive care unit. A facility is described that can meet this need when the anticipated patient load is relatively small.     

Energy Estimation and Measurement in Critically Ill Patients

The estimation of caloric needs of critically ill patients is usually based on energy expenditure (EE), while current recommendations for caloric intake most often rely on a fixed amount of calories. In fact, during the early phase of critical illness, caloric needs are probably lower than EE, as a substantial proportion of EE is covered by the non‐inhibitable endogenous glucose production. Hence, the risk of overfeeding is higher during the early phase than the late phase, while the risk of underfeeding is higher during the late phase of critical illness. Therefore, an accurate measurement of EE can be helpful to prevent early overfeeding and late underfeeding. Available techniques to assess EE include predictive equations, calorimetry, and doubly labeled water, the reference method. The available predictive equations are often inaccurate, while indirect calorimetry is difficult to perform for several reasons, including a shortage of reliable devices and technical limitations. In this review, the authors intend to discuss the different techniques and the influence of the method used on the interpretation of the results of clinical studies.     

外科危重病患者的抗生素使用

目的了解外科危重病患者抗生素的应用. 方法对2002年1月～2003年3月间,我院普外科收治危重病患者的抗生素应用进行统计. 结果所有患者及79%的患者住院期间应用抗生素及β-内酰胺类抗生素,主要为头孢菌素和碳青酶烯类抗生素>50%;经验性治疗却仅有25%的抗生素对真正的致病菌有效;随着患者住院时间的延长,尤其当患者住ICU时间>2周后,抗革兰阳性球菌和真菌的药物用量显著增加. 结论外科危重病患者应用抗生素尤其是β-内酰胺类抗生素非常普遍;经验性抗生素治疗的准确性有待提高;革兰阳性球菌和真菌是患者住院后期的主要致病菌.     

微量元素与危重病关系研究进展

微量元素是危重病患者营养支持的重要组成部分，它们不仅是重要的代谢介质，而且广泛参与细胞免疫、伤口愈合和抗氧化反应的各个环节。在危重病的应激状态下，锌、铜、铁和硒等元素可出现缺乏或功能性缺乏，目前大多数研究显示，在标准营养支持外，需额外补充锌和硒，烧伤患者还需适当补铜，除贫血外不支持常规补铁。     

Priorities Governing the Care of the Critically Ill

Obviously, all patients brought to a critical care unit face the same immediate problem: survival. The chance of survival is greatly enhanced by a systematic approach that applies a certain set of priorities—ventilation, restoration of volume, pumping competence—for dealing with the most urgent threats to life, whatever their origin. Trial and error have no place in the critical care unit.     

Parenteral Fish Oil Lipid Emulsions in the Critically Ill

Introduction: ω‐3 Polyunsaturated fatty acids contained in fish oils (FO) possess major anti‐inflammatory, antioxidant, and immunologic properties that could be beneficial during critical illness. We hypothesized that parenteral FO‐containing emulsions may improve clinical outcomes in the critically ill. Methods: We searched computerized databases from 1980–2012. We included randomized controlled trials (RCTs) conducted in critically ill adult patients that evaluated FO‐containing emulsions, either in the context of parenteral nutrition (PN) or enteral nutrition (EN). Results: A total of 6 RCTs (n = 390 patients) were included; the mean methodological score of all trials was 10 (range, 6–13). When the results of these studies were aggregated, FO‐containing emulsions were associated with a trend toward a reduction in mortality (risk ratio [RR], 0.71; 95% confidence interval [CI], 0.49–1.04; P = .08; heterogeneity I² = 0%) and a reduction in the duration of mechanical ventilation (weighted mean difference in days [WMD], ?1.41; 95% CI, ?3.43 to 0.61; P = .17). However, this strategy had no effect on infections (RR, 0.76; 95% CI, 0.42–1.36; P = .35) and intensive care unit length of stay (WMD, ?0.46; 95% CI, ?4.87 to 3.95; P = .84, heterogeneity I² = 75%). Conclusion: FO‐containing lipid emulsions may be able to decrease mortality and ventilation days in the critically ill. However, because of the paucity of clinical data, there is inadequate evidence to recommend the routine use of parenteral FO. Large, rigorously designed RCTs are required to elucidate the efficacy of parenteral FO in the critically ill.     

Hypocaloric vs Normocaloric Nutrition in Critically Ill Patients

Background: Optimal nutrition of critically ill patients is still a matter of debate. This pilot trial aimed to compare the impact of normocaloric vs hypocaloric feeding in critically ill patients in the first 7 days in the intensive care unit (ICU). The primary end point was the rate of nosocomial infections during the ICU stay. Methods: Critically ill patients requiring artificial nutrition for at least 72 hours were included within 24 hours of ICU admission and randomized into a normocaloric group (receiving 100% of their daily energy expenditure) and a hypocaloric group (receiving 50% of their daily energy expenditure). Results: One hundred patients were included (54 in the normocaloric group and 46 in the hypocaloric group). There were 66 male and 34 female patients with a mean age of 65.8 ± 11.6 years. The mean daily caloric supply was 19.7 ± 5.7 kcal/kg for the normocaloric group and 11.3 ± 3.1 kcal/kg for the hypocaloric group (P = .0001). Insulin demand was significantly higher and gastrointestinal intolerance more frequent in the normocaloric group than in the hypocaloric group. Nosocomial infections were detected more frequently in the hypocaloric group than in the normocaloric group (26.1% vs 11.1%, respectively). The ICU mortality rate was 22.2% in the normocaloric group and 21.7% in the hypocaloric group (not significant). The hospital mortality rate was 31.5% in the normocaloric group and 37.0% in the hypocaloric group (P = .67). Conclusion: Hypocaloric feeding in the first 7 days in critically ill patients was associated with more nosocomial infections but less insulin demand and less gastrointestinal intolerance compared with normocaloric feeding. Trial registration number: DRKS00000104 (German Clinical Trials Register).     

Parenteral Amino Acid Intakes in Critically Ill Children

Background: Parenteral and enteral amino acid requirements for nutrition balance and function have not been defined in critically ill children or adults. In addition to playing a role in protein synthesis, amino acids trigger signaling cascades that regulate various aspects of fuel and energy metabolism and serve as precursors for important substrates. Amino acids can also be toxic. In this study, parenteral intakes of essential and nonessential amino acids (EAAs and NEAAs) supplied to critically ill children were assessed as an initial step for further studies aimed at establishing parenteral amino acid requirements. Methods: A retrospective review was conducted to assess intakes of parenteral amino acid for 116 critically ill children, and these intakes were compared with EAA intakes recommended by the Institute of Medicine. Because there are no recommended intakes for NEAA, NEAA intakes were compared with mixed muscle protein content in the older children and breast milk amino acid content in the infants. Results: Parenteral EAAs were provided in amounts that exceeded recommended intakes for healthy children, except for phenylalanine and methionine, which although excessive, were given in less generous amounts. NEAAs were supplied in lower or higher amounts than the content of mixed muscle proteins or breast milk. Parenteral amino acid formulas are limited in taurine, glutamine, and asparagine despite the fact that inflammatory/immune proteins are rich in these amino acids. Conclusions: Amino acid composition of parenteral formulas is variable and lacks scientific support. Parenteral amino acid intakes should be based on measured requirements to maintain nutrition and functional balance and on knowledge of toxicity.     

Subjective Global Nutritional Assessment in Critically Ill Children

Background: Underweight children admitted to the pediatric intensive care unit (PICU) have a higher risk of mortality than normal‐weight children. The authors hypothesized that subjective global nutrition assessment (SGNA) could identify malnutrition in the PICU and predict nutrition‐associated morbidities. Methods: The authors prospectively evaluated the nutrition status of 150 children (aged 31 days to 5 years) admitted to the PICU with the use of SGNA and commonly used objective anthropometric and laboratory measurements. Each child was administered the SGNA by a dietitian while anthropometric measurements were performed by an independent assessor. To test interrater reproducibility, 76 children had SGNA performed by another dietitian. Occurrence of nutrition‐associated complications was documented for 30 days after admission. Results: SGNA ratings of well nourished, moderately malnourished, or severely malnourished demonstrated moderate to strong correlation with several standard anthropometric measurements (P < .05). The laboratory markers did not demonstrate any correlation with SGNA. Interrater agreement showed moderate reliability (κ = 0.671). Length of stay, pediatric logistic organ dysfunction, and Pediatric Risk of Mortality III were not significantly different across the groups and did not correlate with SGNA.     

成人危重症患者分级护理研究

目的探索成人危重症患者分级护理方案,以期为重症监护病房实施分级护理管理提供参考。方法于2019年5月-11月,以课题组前期研究为基础,采用危重症患者病情严重程度评估体系和护理工时评估体系共16个变量对300例ICU住院患者进行测评,应用聚类分析方法进行数据降维,确定护理分级。结果300例成人危重症患者聚类为三个护理亚群,并根据类属特征将其命名为特A级护理、特B级护理和特C级护理。特A级护理亚群患者病情最重,所需护理工时最长;特B级护理亚群呈现两种情况,一种为患者病情严重但所需护理工时较短,另一种为患者病情较轻但所需护理工时较长;特C级护理患者病情最轻,所需护理工时最短。结论基于聚类分析法确定的成人危重症患者分级护理方案科学性较好,初步获得分级护理基本特征,能够为危重症患者分级护理管理提供参考。