Nutrition support for patients in the intensive care unit

Factors associated with the need of parenteral nutrition in critically ill patients after the initiation of enteral nutrition therapy

Background and aims

Despite enteral nutrition (EN) is the preferred route of nutrition in patients with critical illness, EN is not always able to provide optimal nutrient provision and parenteral nutrition (PN) is needed. This is strongly associated with gastrointestinal (GI) complications, a feature of gastrointestinal dysfunction and disease severity. The aim of the present study was to investigate factors associated with the need of PN after start of EN, together with the use and complications associated with EN.

Methods

Adult patients admitted to 38 Spanish intensive care units (ICUs) between April and July 2018, who needed EN therapy were included in a prospective observational study. The characteristics of EN-treated patients and those who required PN after start EN were analyzed (i.e., clinical, laboratory and scores).

Results

Of a total of 443 patients, 43 (9.7%) received PN. One-third (29.3%) of patients presented GI complications, which were more frequent among those needing PN (26% vs. 60%, p = 0.001). No differences regarding mean energy and protein delivery were found between patients treated only with EN (n = 400) and those needing supplementary or total PN (n = 43). Abnormalities in lipid profile, blood proteins, and inflammatory markers, such as C-Reactive Protein, were shown in those patients needing PN. Sequential Organ Failure Assessment (SOFA) on ICU admission (Hazard ratio [HR]:1.161, 95% confidence interval [CI]:1.053-1.281, p = 0.003) and modified Nutrition Risk in Critically Ill (mNUTRIC) score (HR:1.311, 95% CI:1.098-1.565, p = 0.003) were higher among those who needed PN. In the multivariate analysis, higher SOFA score (HR:1.221, 95% CI:1.057-1.410, p = 0.007) and higher triglyceride levels on ICU admission (HR:1.004, 95% CI:1.001-1.007, p = 0.003) were associated with an increased risk for the need of PN, whereas higher albumin levels on ICU admission (HR:0.424, 95% CI:0.210-0.687, p = 0.016) was associated with lower need of PN.

Conclusion

A higher SOFA and nutrition-related laboratory parameters on ICU admission may be associated with the need of PN after starting EN therapy. This may be related with a higher occurrence of GI complications, a feature of GI dysfunction.

Clinical trial registration

ClinicalTrials.gov: NCT03634943.

Interruptions to Enteral Nutrition in Critically Ill Patients in the Intensive Care Unit

Background

Malnourishment has been linked with increased morbidity and mortality among critically ill patients. The current study aimed to assess the factors contributing to the interruption of enteral nutrition so that preventive measures can be formulated to avoid the malnourishment of critically ill patients.

Methodology

A prospective, observational study was conducted at the Department of Intensive Care Unit, Shifa International Hospital, Islamabad, between November 2020 and May 2021. All patients admitted in the intensive care unit (ICU) during the study period aged between 18 and 80 years, who remained admitted in the medical ICU for at least 72 hours were included in the study. Those who had ileostomy or colostomy were excluded from the study. Diagnostic categories were defined as surgical and medical. Data on clinical parameters including admitting diagnosis and airway-related issues were recorded in a predefined proforma.

Results

The mean duration of enteral nutrition interruption in males was 13.96 ± 13.12 days while that of females, 12.48 ± 12.43 days. Non-invasive ventilation dependency was significantly associated with an interruption in enteral nutrition (p=0.002). The mean duration of interruption of enteral nutrition was not correlated with airway issues (p=0.569). However, the mean duration of interruption of enteral nutrition was significantly lower in patients who underwent spontaneous breathing trials with T-piece (p = 0.032). Those who were advised nil per oral before surgery had a significantly longer duration of enteral nutrition interruption (p < 0.0001) with a mean length of 30.18 ± 5.83 days. The duration of enteral nutrition interruption was significantly longer in patients who had tracheostomy than those who did not have a tracheostomy (26.3 ± 6.34 vs. 9.54 ± 11.61 days) (p < 0.0001).

Conclusion

The present study revealed that at least three-forth of the patients admitted in ICUs had documented orders to the interruption of enteral nutrition. The most significant causes that correlated with interruptions to enteral nutrition were non-invasive ventilation dependency, tracheostomy, spontaneous breathing trials with T-piece, and orders of nil per oral before surgery.

Micronutrient intake from enteral nutrition in critically ill adult patients: A retrospective observational study

OBJECTIVE

The objective of this study was to determine the intake of micronutrients including vitamins B₁₂, D, C, and A; folate; thiamine; iron; zinc; and selenium that are delivered from enteral nutrition (EN) during routine clinical practice in critically ill adults, expressed as a percentage of the Australia and New Zealand nutrient reference values.

METHODS

This single-center retrospective observational study was conducted in Melbourne, Australia during the first 7 d of intensive care unit admission. Mechanically ventilated patients prescribed exclusive EN were considered for inclusion. The primary and secondary outcomes were micronutrient intake expressed as a percentage of the recommended dietary intake (daily intake intended to meet the needs of 97% to 98% of a healthy population) and the upper level of intake (highest daily intake unlikely to pose adverse health effects), respectively. Data are presented as mean (SD) or median [interquartile range].

RESULTS

In total, 57 patients were included (62 (16) y, 67% male). EN was delivered for 5 [4-6] d, with 47% (20) energy adequacy achieved. EN delivery met the recommended dietary intake for vitamin B₁₂, vitamin C, thiamine, and iron and did not meet the recommended dietary intake for vitamin D, vitamin A, folate, zinc, and selenium. No micronutrients exceeded the upper level of intake.

CONCLUSION

EN delivery met the recommended intake for four micronutrients, did not meet the recommended intake for five micronutrients, and did not exceed the upper level of intake for any micronutrient when approximately 50% energy adequacy was achieved types.

Micronutrient intake from enteral nutrition in critically ill adults: A systematic review of randomised controlled trials

OBJECTIVES

The primary objective was to compare the intake of important micronutrients provided from enteral nutrition to critically ill patients with the Australia and New Zealand recommended dietary intakes. A secondary objective was to compare the upper levels of intake and investigate prespecified subgroups.

REVIEW METHOD USED

A systematic literature review was performed.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, and CENTRAL were used.

REVIEW METHODS

Databases were searched for randomised controlled trials that investigated an enteral nutrition intervention as the sole source of nutrition, were published in English between January 2000 and January 8th, 2021, and provided data to calculate micronutrient intake. The primary outcome was the % recommended dietary intake. The quality of individual trials was assessed using the Cochrane Risk of Bias Tool. Outcomes are presented as either mean ± standard deviation or median [interquartile range], with a p < 0.05 considered statistically significant.

RESULTS

Thirteen trials were included (n = 1538 patients). Trials investigating hypocaloric nutrition were excluded from the primary outcome assessment (conducted in nine trials (n = 1220)). All nine trials delivered ≥104% of the recommended dietary intakes and <100% of the upper level of intakes of all micronutrients. In subgroup analyses, trials with ≥80% target energy delivered a higher % of the recommended dietary intake of vitamin B12, thiamine, zinc, and vitamin C. Acute Physiology and Chronic Health Evaluation scores ≥20 delivered a higher % of the recommended dietary intake of vitamin B12 and vitamin A. Antioxidant formulas compared with standard formulas delivered a higher % recommended dietary intake of vitamin C and thiamine. In the four trials that investigated hypocaloric feeding compared with control, there was no difference in micronutrient intake. The quality was low.

CONCLUSIONS

Enteral nutrition delivery frequently met the recommended dietary intakes for all micronutrients investigated and did not exceed the upper levels of intake set for health.

PROSPERO REGISTRATION

CRD42020178333.

The clinical impacts of early using glutamine/arginine enriched high protein density formula at trophic dose in intolerant enteral nutrition cachectic hypoalbuminemic hospitalized patients

BACKGROUND

We sought to evaluate the clinical impacts of the early administration of trophic doses of a glutamine/arginine enriched enteral nutrition formula (ENF) with a high protein density to cachectic hypoalbuminemic hospitalized patients intolerant to enteral nutrition.

METHODS

A retrospective analysis was conducted using the nutritional and non-nutritional data of patients admitted to our institution from April 2017 through August 2019. Patients who died or were discharged before completing ≥1 weeks of hospital admission, or those whose data could not be obtained were excluded. Among other variables, percent changes in serum albumin levels (%∆ALB), C - reactive protein (CRP) and their ratios were expressed as Mean ± SD using the Independent Samples T-test, while categorical variables were expressed as numbers with percentages by using χ2 test. Two tested groups were determined based on the use of ENF: Group I received trophic doses of ENF, while Group II received no enteral nutrition.

RESULTS

The overall hospital length of stay (LOS) and overall 28-day hospital mortality were significantly lower in Group I when compared with Group II with Means ± SDs of (11.32 ± 2.19 days vs 23.49 ± 4.33 days) and (13.13% vs. 28.16%), respectively. Also, significantly higher (%∆ALB) for Group I compared with group II (43.48% ± 7.89% vs. 33.45% ± 6.18%), respectively was observed.

CONCLUSION

In malnourished hypoalbuminemic patients suffering from feeding intolerance, early trophic administration of glutamine/arginine enriched high protein density ENF was well tolerated and may be associated with increased plasma albumin levels, reduced LOS, and overall 28-day mortality, and hence may be considered in such patients.

Measurement of Gastric Residual Volume via Ultrasound after Receiving Intravenous Ondansetron, Metoclopramide, and Neostigmine in Critically Ill Patients: A Double-Blind Clinical Trial

Background

Gastric residual volume (GRV) is considered an important parameter for gastric emptying and nutrition tolerance. This volume is measured before any nutrition and has a direct effect on the volume and timing of the next nutrition. The present study aimed to examine the GRV via ultrasound after receiving intravenous ondansetron, metoclopramide, and neostigmine.

Materials and Methods

In the present study, 40 patients were included in the study, 10 patients were excluded from the study due to death during treatment, and 30 patients were divided into three groups of 10(10 patients in each group).The first, second, and third groups received 2.5, 10, and 8 mg neostigmine, metoclopramide, and ondansetron every 8 h, respectively. The drugs were infused as a micro set in 100 ml normal saline into patients within 30 min. The patients underwent ultrasound imaging and GRV measurement by an intensive care unit (ICU) subspecialty fellow, who was not aware of the drugs received by the patients, in the 1^st h of hospitalization, 6 h after drug injection, and once daily for 4 days.

Results

A total of 40 patients entered the study based on inclusion and exclusion criteria. The effect of neostigmine on reducing GRV (Gastric residual volume) in ICU patients was better than those of the other two drugs, which was significant.

Conclusion

The results of this study showed that neostigmine has a better and significant effect on reducing GRV in ICU patients, compared to those of ondansetron and metoclopramide.

Nutrition Adherence in Critically Ill Patients; How is nutritional intake within the 1st week of hospitalization affecting the patient's Outcome?

Nutritional requirements vary during a patient's stay in the Intensive Care Unit (ICU) and their calculation can be relatively complex. During ICU stay nutrition requirements are rarely met, especially during the initial days of the hospitalization. Studies have shown that poor nutrition is associated with adverse patient outcome. This study examines for correlation between poor nutrition (calories, proteins, lipids and micronutrients) during the 1^st week of ICU stay and adverse patient outcome. Nutritional adherence effect is examined on groups of patients, such as patients with high BMI that receive low nutrition and critically ill males. Regarding the latter analysis, an accuracy rate of 76.4% was achieved when classifying the critically ill males towards their outcome. The results of this work could contribute to the development of smart alarms in the ICU.

Seven Deadly Sins of Nutrition Therapy in Critically Ill Patients

This article presents 7 nutrition steps that, if not followed by the clinical staff, may be metaphorically considered as "7 deadly sins" of nutrition therapy. In this review, we suggest approaches that must be avoided or accomplished to increase compliance with the "Ten Commandments" of good nutrition practice in the intensive care setting. Multiple aggressive and simultaneous sets of therapies are implemented in the intensive care setting, which include nutrition and metabolic support as important components in these therapies. "Sins" should be remembered as a mnemonic device for nutrition standard care in the intensive care unit; this incorporates nutrition adequacy and protocol adherence.

Nutritional status of patients hospitalized in the intensive care unit: A comprehensive report from Iranian hospitals, 2018

INTRODUCTION AND AIM

Malnutrition is a complication of hospitalization in critically ill patients. This event is occurred because of disease and therapeutic processes for curing the patients. Determination of nutritional status helps physicians and clinical nutritionists decide on the best regimen which should be prescribed for a patient. In the current study, we aimed to report the nutritional status ofpatientshospitalizedin the intensive care unit (ICU).

METHOD OF STUDY

We used three standard tolls, including Subjective global assessment (SGA), Nutrition Risk in the Critically Ill (NUTRIC) Score and nutrition risk screening (NRS) questionnaires via a multi-stage sampling for different ICU wards of 32 university hospitals in Iran. Frequencies and rates of nutritional scores, comparative studies, and determined agreement of scoring systems and nutritional status in any ward of hospitals were evaluated.

RESULTS

There were 771 males and 540 female Cancer and trauma patients had the best and worst nutritional scores, respectively. Using NRS and NUTRIC, the low-risk scores were more frequent than thehigh-riskscores among ICU patients. SGA showed that most patients were in grades A (well nutritional status) or B (moderate nutritional status), andfew caseswere in grade C (poor nutritional status).The high-risk nutritional score wasobtained for older patients. NUTRIC and NRS had better agreement for diagnosis and differentiation of malnutrition than NUTRIC-SGA or NRS-SGA pairs. However, there was no strong agreement between the mentioned pairs.

CONCLUSION

Nutritional status of patients hospitalized in ICU wards in Iran wassomewhat better than other countries that this could be due to the highly observed guidelines of patient's care in Iran. Anyway,it is suggested that a more precise tool of nutritional scoresto be validated for patients hospitalized in ICU·In addition, better medical care needs a well evaluation of nutritional insufficiencies and what is necessary for compensation using complementary regimens.

Nutritional Support in Postcardiotomy Shock Extracorporeal Membrane Oxygenation Patients: A Prospective, Observational Study

BACKGROUND

Despite the 6000 patients treated with extracorporeal membrane oxygenation (ECMO) annually, there is a paucity of data regarding the nutritional management of these patients.

MATERIALS AND METHODS

We performed a prospective, observational study of nutrition in postcardiotomy shock patients at our institution. Over a 3.5-year study period, we identified 50 ECMO patients and 225 non-ECMO patients. We identified type, amount, duration, and disruption of nutritional delivery by cohort. The primary outcome was percent of caloric goal met, and secondary outcome was gastrointestinal complications.

RESULTS

ECMO patients met less of their caloric (29% versus 40%, P = 0.017) and protein goals (34% versus 55%, P < 0.001) compared with non-ECMO patients. Tube feeds were administered more slowly (26 versus 37 mL/h, P < 0.001) and held for longer (8.3 versus 4.5 h/d, P < 0.001) in ECMO patients because of procedures (60%) and high-dose pressors (20% versus 7%, P < 0.001). Multivariate analysis demonstrated that ECMO decreased caloric intake by 14%, with no detected increased risk of gastrointestinal complications.

CONCLUSIONS

-ECMO patients received significantly less nutrition support compared with a non-ECMO population. Tube feed hold deficits could potentially be avoided by utilizing postpyloric tubes to feed through procedures, by eliminating holds for vasopressors/inotropes in hemodynamically stable patients, or by establishing volume-based feeding protocols. Further clinical studies are needed to establish efficacy of these interventions and to understand the impact of nutrition on outcomes in ECMO patients.

A prospective study of energy and protein intakes in critically ill patients

BACKGROUND & AIMS

Providing adequate and appropriate food and nutrients satisfying the patients' safe nutritional need is one of the most important care practices for critically ill patients (CIPs) in ICU settings, and is strongly related to the patients' safety.

METHODS

In this prospective cross-sectional study data were collected from a 52-bed medical intensive care unit on 777 consecutive patients in six different ICUs. The patients' weights and heights were measured based on ulna length, knee height, MAC, Calf C, and Wrist C. Also, patient weight change history was asked for. All currently in-use dietary supplements and formulas in the ICU settings were checked for their ingredients. The patients' nutritional need was calculated individually for the disease state based on dietary ESPEN guidelines.

RESULTS

Mean ICU and hospital stay duration was 14.45 ± 11.81 and 15.38 ± 11.88 days respectively. Mean energy and protein requirements in the target population were 1804.61 ± 201.76 Kcal/day and 77.94 ± 12.72 gr/day, respectively. Mean actual energy and protein intakes were 1052.75 ± 561.25 Kcal/day and 35.38 ± 23.19 gr/day, respectively. Satisfaction percents for mean energy and protein requirement in the total population were 58.34% (1052.75/1804.4) and 45.41% (35.38/77.9), respectively. In 21.4% and 4.4% of the studied group, energy and protein intakes were about 75-100% of the patients' actual need, respectively. Another data analysis for patients with over 10 days of inpatient time showed that only 14.2% of patients had energy intakes, and only 3.2% of them had protein intakes in the range of 75-100% of their requirements.

CONCLUSION

Results showed that energy and protein intakes in CIPs are low, disproportionate to their requirements. Therefore, actual dietary intake records, individual dietary requirement calculation, and individual dietary planning in relation with the patients' disease and stress should be considered. Such an accurate nutritional care process can promote patient safety.

Energy, Protein, Carbohydrate, and Lipid Intakes and Their Effects on Morbidity and Mortality in Critically Ill Adult Patients: A Systematic Review

The guidelines for nutritional support in critically ill adult patients differ in various aspects. The optimal amount of energy and nutritional substrates supplied is important for reducing morbidity and mortality, but unfortunately this is not well known, because the topic is complex and every patient is individual. The aim of this review was to gather recent pertinent information concerning the nutritional support of critically ill patients in the intensive care unit (ICU) with respect to the energy, protein, carbohydrate, and lipid intakes and the effect of their specific utilization on morbidity and mortality. Enteral nutrition (EN) is generally recommended over parenteral nutrition (PN) and is beneficial when administered within 24-48 h after ICU admission. In contrast, early PN does not provide substantial advantages in terms of morbidity and mortality, and the time when it is safe and beneficial remains unclear. The most advantageous recommendation seems to be administration of a hypocaloric (<20 kcal · kg^-1 · d^-1), high-protein diet (amino acids at doses of ≥2 g · kg^-1 · d^-1), at least during the first week of critical illness. Another important factor for reducing morbidity is the maintenance of blood glucose concentrations at 120-150 mg/dL, which is accomplished with the use of insulin and lower doses of glucose of 1-2 g · kg^-1 · d^-1, because this prevents the risk of hypoglycemia and is associated with a better prognosis according to recent studies. A fat emulsion is used as a source of required calories because of insulin resistance in the majority of patients. In addition, lipid oxidation in these patients is ∼25% higher than in healthy subjects.

Nutritional Assessment in Critically Ill Patients

BACKGROUND

Malnutrition is an important factor in the survival of critically ill patients. The purpose of the present study was to assess the nutritional status of patients in the intensive care unit (ICU) on the days of admission and discharge via a detailed nutritional assessment.

METHODS

Totally, 125 patients were followed up from admission to discharge at 8ICUs in Shiraz, Iran. The patients' nutritional status was assessed using subjective global assessment (SGA), anthropometric measurements, biochemical indices, and body composition indicators. Diet prescription and intake was also evaluated.

RESULTS

Malnutrition prevalence significantly increased on the day of discharge (58.62%) compared to the day of admission (28.8%) according to SGA (P<0.001). The patients' weight, mid-upper-arm circumference, mid-arm muscle circumference, triceps skinfold thickness, and calf circumference decreased significantly as well (P<0.001). Lean mass weight and body cell mass also decreased significantly (P<0.001). Biochemical indices showed no notable changes except for magnesium, which decreased significantly (P=0.013). A negative significant correlation was observed between malnutrition on discharge day and anthropometric measurements. Positive and significant correlations were observed between the number of days without enteral feeding, days delayed from ICU admission to the commencement of enteral feeding, and the length of ICU stay and malnutrition on discharge day. Energy and protein intakes were significantly less than the prescribed diet (26.26% and 26.48%, respectively).

CONCLUSION

Malnutrition on discharge day increased in the patients in the ICU according to SGA. Anthropometric measurements were better predictors of the nutritional outcome of our critically ill patients than were biochemical tests.

The prevalence and consequences of malnutrition risk in elderly Albanian intensive care unit patients

PURPOSE

Many investigators have reported rising numbers of elderly patients admitted to the intensive care units (ICUs). The aim of the study was to estimate the prevalence of malnutrition risk in the ICU by comparing the prevalence of malnutrition between older adults (aged 65 years and above) and adults (aged 18-64 years), and to examine the negative consequences associated with risk of malnutrition in older adults.

MATERIALS AND METHODS

A prospective cohort study in the ICU of the University Hospital Center of Tirana, Albania, was conducted. Logistic regression analysis was used to analyze the effect of malnutrition risk on the length of ICU stay, the duration of being on the ventilator, the total complications, the infectious complications, and the mortality.

RESULTS

In this study, 963 patients participated, of whom 459 patients (47.7%) were aged ≥65 years. The prevalence of malnutrition risk at the time of ICU admission of the patients aged ≥65 years old was 71.24%. Logistic regression adjusted for confounders showed that malnutrition risk was an independent risk factor of poor clinical outcome for elderly ICU patients, for 1) infections (odds ratio [OR] =4.37; 95% confidence interval [CI]: 2.61-7.31); 2) complications (OR =6.73; 95% CI: 4.26-10.62); 3) mortality (OR =2.68; 95% CI: 1.72-4.18); and 4) ICU length of stay >14 days (OR =5.18, 95% CI: 2.43-11.06).

CONCLUSION

Malnutrition risk is highly prevalent among elderly ICU patients, especially among severely ill patients with malignancy admitted to the emergency ward. ICU elderly patients at malnutrition risk will have higher complication and infection rates, longer duration of ICU stay, and increased mortality. Efforts should be made to implement a variety of nutritional care strategies, to change the nutritional practices not only at ward level, but nationally, according to the best clinical practice and recent guidelines.

Randomized clinical trial of arginine-supplemented enteral nutrition versus standard enteral nutrition in patients undergoing gastric cancer surgery

PURPOSE

Significant malnutrition exists in a high percentage of patients with gastric cancer. It is, therefore, crucial to establish an effective means to provide nutrition for these patients. This prospective, randomized, double-blinded clinical trial aims to assess the long-term survival of arginine-supplementation enteral nutrition versus standard enteral nutrition in malnourished patients with gastric cancer.

METHODS

The control group (36 cases) received postoperative standard enteral nutrition. Meanwhile, the arginine-supplementation group (37 cases) adopted the same nutrition product but enriched with arginine (9.0 g/L). The primary study objective was overall survival (OS). Secondary endpoints were progression-free survival (PFS); serum parameters including total protein, albumin, proalbumin, and transferrin obtained on preoperative day 1, postoperative day 2, and day 12; CD4(+) and CD8(+) T cells, natural killer (NK) cells, immunoglobulin M (IgM), and immunoglobulin G (IgG) obtained on preoperative day 1 and postoperative day 7.

RESULTS

No significant differences in baseline characteristics were observed between groups. The group receiving arginine-enriched nutrition had a significantly better OS (P = 0.03, 41 vs. 30.5 months) and better PFS (P = 0.02, 18 vs. 11.5 months). On postoperative day 7, CD4(+) T cells, NK cells, IgM and IgG levels of the arginine-supplemented group increased prominently and were significantly higher than those of the control group and those on preoperative day 1. There is no significant difference in the serum total protein, albumin, proalbumin, and transferrin levels between the two arms.

CONCLUSIONS

Arginine-supplemented enteral nutrition significantly improves long-term survival and restores immunity in malnourished gastric cancer.

Nutrition therapy for critically ill and injured patients

BACKGROUND

Nutrition support has undergone significant advances in recent decades, revolutionizing the care of critically ill and injured patients. However, providing adequate and optimal nutrition therapy for such patients is very challenging: it requires careful attention and an understanding of the biology of the individual patient's disease or injury process, including insight into the consequent changes in nutrients needed.

OBJECTIVE

The objective of this article is to review the current principles and practices of providing nutrition therapy for critically ill and injured patients.

METHODS

Review of the literature and evidence-based guidelines.

RESULTS

The evidence demonstrates the need to understand the biology of nutrition therapy for critically ill and injured patients, tailored to their individual disease or injury, age, and comorbidities.

CONCLUSION

Nutrition therapy for critically ill and injured patients has become an important part of their overall care. No longer should we consider nutrition for critically ill and injured patients just as "support" but, rather, as "therapy", because it is, indeed, a key therapeutic modality.

Respiratory Dysfunction in Ventilated Patients: Can Inspiratory Muscle Training Help?

Respiratory muscle dysfunction is associated with prolonged and difficult weaning from mechanical ventilation. This dysfunction in ventilator-dependent patients is multifactorial: there is evidence that inspiratory muscle weakness is partially explained by disuse atrophy secondary to ventilation, and positive end-expiratory pressure can further reduce muscle strength by negatively shifting the length-tension curve of the diaphragm. Polyneuropathy is also likely to contribute to apparent muscle weakness in critically ill patients, and nutritional and pharmaceutical effects may further compound muscle weakness. Moreover, psychological influences, including anxiety, may contribute to difficulty in weaning. There is recent evidence that inspiratory muscle training is safe and feasible in selected ventilator-dependent patients, and that this training can reduce the weaning period and improve overall weaning success rates. Extrapolating from evidence in sports medicine, as well as the known effects of inspiratory muscle training in chronic lung disease, a theoretical model is proposed to describe how inspiratory muscle training enhances weaning and recovery from mechanical ventilation. Possible mechanisms include increased protein synthesis (both Type 1 and Type 2 muscle fibres), enhanced limb perfusion via dampening of a sympathetically-mediated metaboreflex, reduced lactate levels and modulation of the perception of exertion, resulting in less dyspnoea and enhanced exercise capacity.

Malabsorption and nutritional balance in the ICU: fecal weight as a biomarker: a prospective observational pilot study

INTRODUCTION

Malabsorption, which is frequently underdiagnosed in critically ill patients, is clinically relevant with regard to nutritional balance and nutritional management. We aimed to validate the diagnostic accuracy of fecal weight as a biomarker for fecal loss and additionally to assess fecal macronutrient contents and intestinal absorption capacity in ICU patients.

METHODS

This was an observational pilot study in a tertiary mixed medical-surgical ICU in hemodynamically stable adult ICU patients, without clinically evident gastrointestinal malfunction. Fecal weight (grams/day), fecal energy (by bomb calorimetry in kcal/day), and macronutrient content (fat, protein, and carbohydrate in grams/day) were measured. Diagnostic accuracy expressed in terms of test sensitivity, specificity, positive (PPV) and negative predictive value (NPV), and receiver operator curves (ROCs) were calculated for fecal weight as a marker for energy malabsorption. Malabsorption was a priori defined as < 85% intestinal absorption capacity.

RESULTS

Forty-eight patients (63 ± 15 years; 58% men) receiving full enteral feeding were included. A cut-off fecal production of > 350 g/day (that is, diarrhea) was linked to the optimal ROC (0.879), showing a sensitivity and PPV of 80%, respectively. Specificity and NPV were both 96%. Fecal weight (grams/day) and intestinal energy-absorption capacity were inversely correlated (r = -0.69; P < 0.001). Patients with > 350 g feces/day had a significantly more-negative energy balance compared with patients with < 350 g feces/day (loss of 627 kcal/day versus neutral balance; P = 0.012).

CONCLUSIONS

A fecal weight > 350 g/day in ICU patients is a biomarker applicable in daily practice, which can act as a surrogate for fecal energy loss and intestinal energy absorption. Daily measurement of fecal weight is a feasible means of monitoring the nutritional status of critically ill patients and, in those identified as having malabsorption, can monitor responses to changes in dietary management.

Nutrition and clinical outcome in intensive care patients

PURPOSE OF REVIEW

In the setting of ICU, the characteristics of patients have changed during the last decade. Patients are older, frequently overweight or obese, present with more chronic diseases and undernutrition. These conditions are characterized by reduced muscle mass and vulnerable homeostasis. This review sustains the hypothesis that an early and optimal nutritional support, combining enteral and parenteral nutrition, could improve the clinical outcome of ICU patients.

RECENT FINDINGS

The combination of stress and undernutrition observed in the ICUs is associated with negative energy balance, which leads to lean body mass loss. Catabolism of lean body mass has been repeatedly associated with a worsening of the clinical outcome, increased length of hospital stay, recovery and healthcare costs. Early enteral nutrition is the recommended feeding route in ICU patients, but it is often unable to fully cover the nutritional needs. Parenteral nutrition is recommended if enteral nutrition is not feasible.

SUMMARY

It is hypothesized that supplemental parenteral nutrition, together with insufficient enteral nutrition, could optimize the nutritional therapy by preventing the onset of early energy deficiency, and thus, could allow to reduce the side-effects of undernutrition and promote better chances of recovery after the ICU stay.

Critical care nutrition for feline patients

Nutritional treatment in critical care patients is an important component of the complete treatment plan. Assessment of nutritional status and careful consideration of the disease course will help guide the selection of the most appropriate assisted-feeding method. Enteral nutrition is favored over parenteral nutrition when the gastrointestinal tract is functional. Common routes of enteral feeding include nasoesophageal, esophagostomy, gastrostomy, and jejunostomy feeding tubes. Parenteral nutrition is indicated for patients who cannot tolerate enteral feedings, or are poor anesthetic candidates for proper feeding tube placement. Appropriate diet selection and implementation of proper feeding guidelines and monitoring will aide in limiting complications associated with enteral and/or parenteral feeding.

Monitoring the clinical introduction of a glutamine and antioxidant solution in critically ill trauma and burn patients

OBJECTIVE

Enteral glutamine supplementation and antioxidants have been shown to be beneficial in some categories of critically ill patients. This study investigated the impact on organ function and clinical outcome of an enteral solution enriched with glutamine and antioxidant micronutrients in patients with trauma and with burns.

METHODS

This was a prospective study of a historical control group including critically ill, burned and major trauma patients (n = 86, 40 patients with burns and 46 with trauma, 43 in each group) on admission to an intensive care unit in a university hospital (matching for severity, age, and sex). The intervention aimed to deliver a 500-mL enteral solution containing 30 g of glutamine per day, selenium, zinc, and vitamin E (Gln-AOX) for a maximum of 10 d, in addition to control treatment consisting of enteral nutrition in all patients and intravenous trace elements in all burn patients.

RESULTS

Patients were comparable at baseline, except for more inhalation injuries in the burn-Gln-AOX group (P = 0.10) and greater neurologic impairment in the trauma-Gln-AOX group (P = 0.022). Intestinal tolerance was good. The full 500-mL dose was rarely delivered, resulting in a low mean glutamine daily dose (22 g for burn patients and 16 g for trauma patients). In burn patients intravenous trace element delivery was superior to the enteral dose. The evolution of the Sequential Organ Failure Assessment score and other outcome variables did not differ significantly between groups. C-reactive protein decreased faster in the Gln-AOX group.

CONCLUSION

The Gln-AOX supplement was well tolerated in critically ill, injured patients, but did not improve outcome significantly. The delivery of glutamine below the 0.5-g/kg recommended dose in association with high intravenous trace element substitution doses in burn patients are likely to have blunted the impact by not reaching an efficient treatment dose. Further trials testing higher doses of Gln are required.