Biochemical Markers of Nutrition Support in Critically Ill Trauma Victims

Dynamic assessment of prealbumin for nutrition support effectiveness in critically ill patients

BACKGROUND & AIMS

Serum prealbumin is considered to be a sensitive predictor of clinical outcomes and a quality marker for nutrition support. However, its susceptibility to inflammation restricts its usage in critically ill patients according to current guidelines. We assessed the performance of the initial value of prealbumin and dynamic changes for predicting the ICU mortality and the effectiveness of nutrition support in critically ill patients.

METHODS

This monocentric study included patients admitted to the ICU between 2009 and 2016, having at least one initial prealbumin value available. Prospectively recorded data were extracted from the electronic ICU charts. We used both univariable and multivariable logistic regressions to estimate the performance of prealbumin for the prediction of ICU mortality. Additionally, the association between prealbumin dynamic changes and nutrition support was assessed via a multivariable linear mixed-effects model and multivariable linear regression. Performing subgroup analysis assisted in identifying patients for whom prealbumin dynamic assessment holds specific relevance.

RESULTS

We included 3136 patients with a total of 4942 prealbumin levels available. Both prealbumin measured at ICU admission (adjusted odds-ratio (aOR) 0.04, confidence interval (CI) 95% 0.01-0.23) and its change over the first week (aOR 0.02, CI 95 0.00-0.19) were negatively associated with ICU mortality. Throughout the entire ICU stay, prealbumin dynamic changes were associated with both cumulative energy (estimate: 33.2, standard error (SE) 0.001, p < 0.01) and protein intakes (1.39, SE 0.001, p < 0.01). During the first week of stay, prealbumin change was independently associated with mean energy (6.03e-04, SE 2.32e-04, p < 0.01) and protein intakes (1.97e-02, SE 5.91e-03, p < 0.01). Notably, the association between prealbumin and energy intake was strongest among older or malnourished patients, those suffering from increased inflammation and those with high disease severity. Finally, prealbumin changes were associated with a positive mean nitrogen balance at day 7 only in patients with SOFA <4 (p = 0.047).

CONCLUSION

Prealbumin measured at ICU admission and its change during the first-week serve as an accurate predictor of ICU mortality. Prealbumin dynamic assessment may be a reliable tool to estimate the effectiveness of nutrition support in the ICU, especially among high-risk patients.

Association of prealbumin with short-term and long-term outcomes in patients with acute ST-segment elevation myocardial infarction

BACKGROUND

Prealbumin is considered to be a useful indicator of nutritional status. Furthermore, it has been found to be associated with severities and prognosis of a range of diseases. However, limited data on the association of baseline prealbumin level with outcomes of patients with acute ST-segment elevation myocardial infarction (STEMI) are available.

METHODS

We analyzed 2313 patients admitted for acute STEMI between October 2013 and December 2020. In-hospital outcomes and mortality during the 49 months (interquartile range: 26-73 months) follow-up period were compared between patients with the low prealbumin level (< 170 mg/L) and those with the high prealbumin level (≥ 170 mg/L).

RESULTS

A total of 114 patients (4.9%) died during hospitalization. After propensity score matching, patients with the low prealbumin level than those with the high prealbumin level experienced higher incidences of heart failure with Killip class III (9.9% vs. 4.4%, P = 0.034), cardiovascular death (8.4% vs. 3.4%, P = 0.035) and the composite of major adverse cardiovascular events (19.2% vs. 10.3%, P = 0.012). Multivariate logistic regression analysis identified that the low prealbumin level (< 170 mg/L) was an independent predictor of in-hospital major adverse cardiovascular events (odds ratio = 1.918, 95% CI: 1.250-2.942, P = 0.003). The cut-off value of prealbumin level for predicting in-hospital death was 170 mg/L (area under the curve = 0.703, 95% CI: 0.651-0.754, P < 0.001; sensitivity = 0.544, specificity = 0.794). However, after multivariate adjustment of possible confounders, baseline prealbumin level (170 mg/L) was no longer independently associated with 49-month cardiovascular death. After propensity score matching, Kaplan-Meier survival curves revealed consistent results.

CONCLUSIONS

Decreased prealbumin level closely related to unfavorable short-term outcomes. However, after multivariate adjustment and controlling for baseline differences, baseline prealbumin level was not independently associated with an increased risk of long-term cardiovascular mortality in STEMI patients.

Factors Associated with Nutritional Risk Assessment in Critically Ill Patients Using the Malnutrition Universal Screening Tool (MUST)

Background: Malnutrition is an underdiagnosed condition that negatively affects the clinical outcomes of patients, being associated with an increased risk of adverse events, increased hospital stay, and higher mortality. Therefore, nutritional assessment is a required and necessary process in patient care. The objective of this study was to identify the factors associated with nutritional risk by applying the Malnutrition Universal Screening Tool (MUST) scale in a population of critically ill patients. Methods: This was an observational, analytical, and retrospective study. Sociodemographic, clinical, hematological, and biochemical variables and their relationship with nutritional risk and mortality were analyzed. Results: Of 630 patients, the leading cause of admission was pathologies of the circulatory and respiratory system (50%); 28.4% were at high nutritional risk; and mortality was 11.6% and associated with nutritional risk, hemoglobin, and plasma urea nitrogen. Conclusions: The presence of gastrointestinal symptoms and the type of nutritional support received during hospitalization could increase the likelihood of presenting a medium/high nutritional risk, while polycythemia reduced this probability. An associative model was found to determine nutritional risk with an adequate specificity and diagnostic validity index.

Evaluation of plasma prealbumin as a novel inflammatory biomarker in dogs: a pilot study

Introduction

Prealbumin (PAB) is a plasma protein synthesized in the hepatic parenchymal cells. PAB has a short half-life (~2 days), and its concentration is affected by changes in transcapillary escape. Measurement of PAB is widely used in hospitalized patients in human medicine due to its decreasing concentration in states of inflammation and malnutrition. However, only a few studies are available in dogs. The aim of this study is to determine whether the plasma PAB concentration decreases in dogs with inflammation and to evaluate the relationship between the plasma PAB concentration and inflammation-related parameters in dogs.

Methods

A total of 94 dogs were divided into healthy (n = 33) and diseased (n = 61) groups. These were further divided into group A (n = 24) and group B (n = 37) according to plasma C-reactive protein (CRP) levels. Group A included dogs with a plasma CRP < 10 mg/L, and group B consisted of dogs with a plasma CRP ≥ 10 mg/L. Patient signalment, history, physical examination findings, hematologic and biochemical parameters, various inflammatory markers, and plasma PAB levels were investigated and compared between groups.

Results

The plasma PAB concentration was found to be lower in group B than in the other groups (p < 0.001), but no statistical difference was found when comparing the control group and group A (p > 0.05). A plasma PAB < 6.3 mg/dL predicted an increased CRP level (10 mg/L or greater) with a sensitivity of 89.5% and a specificity of 86.5%. Receiver operating characteristic curve analysis revealed that the area under the curve for PAB was higher than that for the white blood cell count, neutrophil count, albumin level, lactate level, neutrophil-to-lymphocyte ratio, and neutrophil percentage-to-albumin ratio. In addition, the PAB concentration was significantly negatively correlated with the CRP concentration (r = -0.670, p < 0.001).

Conclusion

In conclusion, this is the first study to demonstrate the clinical usefulness of the plasma PAB concentration as an inflammatory marker in dogs. These findings suggest that measuring the plasma PAB concentration along with the CRP concentration may be more useful for evaluating inflammation than measuring CRP alone in canine patients.

Fractional Gluconeogenesis: A Biomarker of Dietary Energy Adequacy in a Rat Brain Injury Model

Patients treated for traumatic brain injury (TBI) are in metabolic crises because of the trauma and underfeeding. We utilized fractional gluconeogenesis (fGNG) to assess nutritional adequacy in ad libitum-fed and calorically-restricted rats following TBI. Male Sprague-Dawley individually housed rats 49 days of age were randomly assigned into four groups: ad libitum (AL) fed control (AL-Con, sham), AL plus TBI (AL+TBI), caloric restriction (CR) control (CR-Con, sham), and CR plus TBI (CR+TBI). From days 1-7 animals were given AL access to food and water containing 6% deuterium oxide (D₂O). On day 8, a pre-intervention blood sample was drawn from each animal, and TBI, sham injury, and CR protocols were initiated. On day 22, the animals were euthanized, and blood was collected to measure fGNG. Pre-intervention, there was no significant difference in fGNG among groups (p ≥ 0.05). There was a significant increase in fGNG due to caloric restriction, independent of TBI (p ≤ 0.05). In addition, fGNG may provide a real-time, personalized biomarker for assessing patient dietary caloric needs.

Prealbumin as a nutrition status indicator may be associated with outcomes of geriatric hip fractures: a propensity score matching and 1-year follow-up study

AIM

Nutrition status may affect bone metabolism and regeneration in the elderly. However, few studies reported a sensitive nutrition indicator or evaluation tool for geriatric hip fractures. This study aimed to explore if prealbumin (PAB), a critical nutrition-related protein, is related to the prognosis of hip fractures.

METHODS

Patients with hip fractures who met the inclusion criteria were included in our study. Geriatric nutritional risk index (GNRI) and prognostic nutritional index (PNI) were calculated. Propensity score matching (PSM) was used to reduce the influence of confounding factors and ROC curves were conducted to explore the optimal cutoff points of PAB and to compare the prognostic value between GNRI, PNI, and PAB. Then Cox and Logistics analyses were performed to identify the relation between PAB and outcomes of hip fractures.

RESULTS

Out of the 546 patients enrolled in this study, 91 patients died within one year. After a 1:1 PSM, the patients with less than 1-year survival had significantly lower PAB (p < 0.001) than those who were still alive at one year. ROC curves showed that the PAB may sensitively predict 6-month survival (AUROC: 0.695), 1-year survival (AUROC: 0.696), and 1-year-free walking ability (AUROC: 0.642). Logistics analysis showed that low PAB may be an independent risk factor for survival and 1-year-free walking ability.

CONCLUSION

Low levels of PAB may be associated with poor survival and walking abilities of older patients after surgery for hip fracture.

Effect of Early Enteral Nutrition Support Combined with Chemotherapy on Related Complications and Immune Function of Patients after Radical Gastrectomy

Objective

The purpose was to analyze the effect of early enteral nutrition (EEN) support combined with chemotherapy on related complications and immune function in patients after radical gastrectomy.

Methods

80 patients with gastric cancer treated in our hospital from March 2019 to March 2020 were selected as the research objects and divided into the experimental group and control group according to the random number table, with 40 cases in each group. The control group received chemotherapy only after surgery, while the experimental group received EEN on this basis. The total protein (TP), transferrin (TF), albumin (ALB), immune cells, and other indexes were measured in the two groups before and after treatment to analyze the effect of different treatment methods on the complications and immune function of patients after radical gastrectomy.

Results

There were no significant differences in gender ratio, average age, average BMI, pathological types, disease staging, and residence between the two groups (P > 0.05). The exhaust recovery time, total gastric tube drainage, fluid intake time, and hospitalization time in the experimental group were significantly lower than those in the control group (P < 0.05). There were no significant differences in the TP, TF, and ALB levels between the two groups before treatment (P > 0.05), and the TP, TF, and ALB levels in the experimental group were significantly higher than those in the control group after treatment (P < 0.05). The CD4⁺/CD8⁺, CD3⁺, and CD4⁺ levels in the experimental group after treatment were significantly higher than those in the control group (P < 0.001). After treatment, the growth hormone levels in both groups significantly increased (P < 0.001), and the growth hormone level in the experimental group was significantly higher than that in the control group (P < 0.001). There was no significant difference in the KPS scores between the two groups before treatment (P > 0.05), and the KPS score in the experimental group was significantly higher than that in the control group after treatment (P < 0.001). The incidence of postoperative complications in the experimental group was significantly lower than that in the control group (P < 0.05).

Conclusion

EEN combined with chemotherapy is a reliable method to improve the immune function of patients after radical gastrectomy for gastric cancer, which plays an important role in improving the physical state of patients and reducing the incidence of complications. Therefore, its further research will help to establish a better treatment plan for such patients.

Transthyretin at Admission and Over Time as a Marker for Clinical Outcomes in Critically Ill Trauma Patients: A Prospective Single-Center Study

Background

Transthyretin (TTR) has been described as a predictor for outcomes in medical and surgical patients. However, the association of TTR on admission and over time on outcomes has not yet been prospectively assessed in trauma patients.

Methods

This is a prospective observational study including trauma patients admitted to the intensive care unit (ICU) of a large Level I trauma center 05/2014–05/2015. TTR levels at ICU admission and all subsequent values over time were recorded. Patients were observed for 28 days or until hospital discharge. The association of outcomes and TTR levels at admission and over time was assessed using multivariable regression and generalized estimating equation (GEE) analysis, respectively.

Results

A total of 237 patients with TTR obtained at admission were included, 69 of whom had repeated TTR measurements. Median age was 40.0 years and median ISS 16.0; 83.1% were male. Below-normal TTR levels at admission (41.8%) were independently associated with higher in-hospital mortality (p = 0.042), more infectious complications (p = 0.032), longer total hospital length of stay (LOS) (p = 0.013), and ICU LOS (p = 0.041). Higher TTR levels over time were independently associated with lower in-hospital mortality (p = 0.015), fewer infections complications (p = 0.028), shorter total hospital and ICU LOS (both p < 0.001), and fewer ventilator days (0.004).

Conclusions

In critically ill trauma patients, below-normal TTR levels at admission were independently associated with worse outcomes and higher TTR levels over time with better outcomes, including lower in-hospital mortality, less infectious complications, shorter total hospital and ICU LOS, and fewer ventilator days. Based on these results, TTR may be considered as a prognostic marker in this patient population.

Biomarkers in critical care nutrition

The goal of nutrition support is to provide the substrates required to match the bioenergetic needs of the patient and promote the net synthesis of macromolecules required for the preservation of lean mass, organ function, and immunity. Contemporary observational studies have exposed the pervasive undernutrition of critically ill patients and its association with adverse clinical outcomes. The intuitive hypothesis is that optimization of nutrition delivery should improve ICU clinical outcomes. It is therefore surprising that multiple large randomized controlled trials have failed to demonstrate the clinical benefit of restoring or maximizing nutrient intake. This may be in part due to the absence of biological markers that identify patients who are most likely to benefit from nutrition interventions and that monitor the effects of nutrition support. Here, we discuss the need for practical risk stratification tools in critical care nutrition, a proposed rationale for targeted biomarker development, and potential approaches that can be adopted for biomarker identification and validation in the field.

The malnutrition in polytrauma patients (MaPP) study: Research protocol

BACKGROUND

Polytrauma patients are at risk of considerable harm from malnutrition due to the metabolic response to trauma. However, there is little knowledge of (the risk of) malnutrition and its consequences in these patients. Recognition of sub-optimally nourished polytrauma patients and their nutritional needs is crucial to prevent complications and optimize their clinical outcomes.

AIM

The primary objective is to investigate whether polytrauma patients admitted to the Intensive Care Unit (ICU) who have or develop malnutrition have a higher complication rate than patients who are and remain well nourished. Secondary objectives are to determine the prevalence of pre-existent and in-hospital acquired malnutrition in these patients, to assess the association between malnutrition and long-term outcomes, and to determine the association between serum biomarkers (albumin and pre-albumin) and malnutrition.

METHODS

This international observational prospective cohort study will be performed at three Level-1 trauma centers in the United States and two Level-1 centers in the Netherlands. Adult polytrauma patients (Injury Severity Score ≥16) admitted to the ICU of one of the participating centers directly from the Emergency Department are eligible for inclusion. Nutritional status and risk of malnutrition will be assessed using the Subjective Global Assessment (SGA) scale and Nutritional Risk in Critically Ill (NUTRIC) score, respectively. Nutritional intake, biomarkers and complications will be collected daily. Patients will be followed up to one year after discharge for long-term outcomes.

CONCLUSIONS

This international prospective cohort study aims to gain more insight into the effect and consequences of malnutrition in polytrauma patients admitted to the ICU.

Increasing Enteral Protein Intake in Critically Ill Trauma and Surgical Patients

BACKGROUND

Published guidelines recommend providing at least 2 g/kg/d of protein for critically ill surgical patients. It may be difficult to achieve this level of intake using standard enteral formulas, thus necessitating protein or amino acid supplementation. Herein, we report our approach to enteral protein supplementation and its relationship with urinary nitrogen excretion and serum transthyretin concentrations.

METHODS

This was a retrospective cohort study in which we reviewed critically ill trauma and surgical patients treated with supplemental enteral protein according to a protocol aiming to deliver a total of 2 g/kg/d of protein. We collected detailed nutrition data over a 2-week period after admission and obtained additional data through discharge to determine caloric and protein intake as well as complications. We also compared urine nitrogen excretion and transthyretin concentrations between these patients and a control group who did not receive supplemental protein.

RESULTS

Fifty-three subjects received early protein supplementation. Formula and protein supplement each provided ≈1.2 g/kg/d of protein by intensive care unit day 4. This resulted in a median total protein intake of 2.2 g/kg/d through day 14. One patient developed acute kidney injury, and 1 patient had 3 episodes of vomiting. By the third week, serum transthyretin concentrations increased to a median of 21 mg/dL compared with 13 mg/dL in subjects not receiving early supplementation.

CONCLUSION

It is safe to deliver supplemental protein enterally to critically ill surgical and trauma patients and reach 2 g/kg/d of protein intake during the first week of illness.

Early Enteral Nutrition Adequacy Mitigates the Neutrophil-Lymphocyte Ratio Improving Clinical Outcomes in Critically Ill Surgical Patients

BACKGROUND

Neutrophil-lymphocyte ratio (NLR) is a measure of host inflammatory response; a higher NLR is associated with worse clinical outcomes. Enteral nutrition (EN) may mitigate inflammation through interaction with gut-associated lymphoid tissue. We hypothesized that early EN adequacy in critically ill surgical patients is associated with lower NLR and better clinical outcomes.

METHODS

In this retrospective study, we analyzed data from adult surgical intensive care unit (ICU) patients receiving EN. NLR at baseline ICU admission (NLR-B), NLR after 3-5 days of EN (F-NLR), nutrition adequacy, caloric deficit (CD), protein deficit (PD), hospital length of stay (LOS), ICU LOS, 28-day ventilator-free days (28-VFD), and in-hospital mortality were collected. Tertiles groups were created for NLR, F-NLR, CD, and PD; the highest (H) and lowest (L) tertiles were compared. Regression analyses were performed to control for effect of age, gender, APACHE II, and NLR.

RESULTS

Subjects in the L-CD group had lower median F-NLR (7 [range, 5-11] vs 10 [7-22], P = 0.005) and shorter ICU LOS (9 [6-16]) vs 16 [9-32] days; P = 0.006). The L-NLR group had shorter hospital LOS (18 [10-31] vs 22 [15-38] days, P = 0.023), greater 28-VFD (23 [18-25] vs 19 [11-22] days, P = 0.005), and lower in-hospital mortality (13% vs 41%, P = 0.002).

CONCLUSION

In critically ill surgical patients, early enteral caloric adequacy is associated with less inflammation and improved clinical outcomes.

Transthyretin levels: Potential biomarker for monitoring nutritional support efficacy and clinical complications risk in patients receiving parenteral nutrition

Nutritional support is an effective strategy to restore or maintain nutritional status, to reduce clinical complications, hospitalization period and the morbidity/mortality risk of hospitalized patients. So, a good marker is important to evaluate the nutritional support.

OBJECTIVES

This study aims to evaluate the evolution of transthyretin levels in patients receiving parenteral nutrition (PN) during 14 days.

DESIGN & METHODS

Longitudinal study of 88 hospitalized patients. The assessments and samples were taken during the first 72 h (T0), on the 7th day (T7) and 14th day (T14) of PN. This study was approved by the Ethics Committee of the School of Medical Sciences at UNICAMP (No 538/2011).

RESULTS

The C-reactive protein (CRP) levels were high and albumin and transthyretin levels were low at baseline. From T0 to T14, only transthyretin increased (p = 0.03). According to the receiver operation characteristic (ROC) curve, we found that the transthyretin had some improvement when the CRP levels were less than 10.4 mg/dl (T7). According to the CRP/albumin ratio, all patients classified as without risk for complications were discharged from the hospital. In addition, we observed that patients with transthyretin reduction had a concomitant higher risk for complications according to their ratio CRP/albumin (p = 0.03).

CONCLUSIONS

CRP/albumin ratio was associated with the evolution of transthyretin levels. Transthyretin values showed significant improvement in the 14 days of PN. Especially, less inflamed patients (ie CRP less than 10.4 mg/dl) improved their transthyretin levels. So, CRP value at day 7 that predicts the transthyretin and transthyretin is a good biomarker for classification of nutritional support and clinical complications risk in patients receiving PN.