The metabolic and nutritional effects of injury and sepsis

Malnutrition and its effects in severely injured trauma patients

Purpose

In hospitalized patients, malnutrition is associated with adverse outcomes. However, the consequences of malnutrition in trauma patients are still poorly understood. This study aims to review the current knowledge about the pathophysiology, prevalence, and effects of malnutrition in severely injured patients.

Methods

A systematic literature review in PubMed and Embase was conducted according to PRISMA-guidelines.

Results

Nine review articles discussed the hypermetabolic state in severely injured patients in relation to malnutrition. In these patients, malnutrition negatively influenced the metabolic response, and vice versa, thereby rendering them susceptible to adverse outcomes and further deterioration of nutritional status. Thirteen cohort studies reported on prevalences of malnutrition in severely injured patients; ten reported clinical outcomes. In severely injured patients, the prevalence of malnutrition ranged from 7 to 76%, depending upon setting, population, and nutritional assessment tool used. In the geriatric trauma population, 7–62.5% were malnourished at admission and 35.6–60% were at risk for malnutrition. Malnutrition was an independent risk factor for complications, mortality, prolonged hospital length of stay, and declined quality of life.

Conclusions

Despite widespread belief about the importance of nutrition in severely injured patients, the quantity and quality of available evidence is surprisingly sparse, frequently of low-quality, and outdated. Based on the malnutrition-associated adverse outcomes, the nutritional status of trauma patients should be routinely and carefully monitored. Trials are required to better define the optimal nutritional treatment of trauma patients, but a standardized data dictionary and reasonable outcome measures are required for meaningful interpretation and application of results.

Electronic supplementary material

The online version of this article (10.1007/s00068-020-01304-5) contains supplementary material, which is available to authorized users.

Obesity as protective against, rather than a risk factor for, postoperative Clostridium difficile infection: A nationwide retrospective analysis of 1,426,807 surgical patients

BACKGROUND

Recent studies suggest that obesity is a risk factor for Clostridium difficile infection, possibly due to disruptions in the intestinal microbiome composition. We hypothesized that body mass index (BMI) is associated with increased incidence of C. difficile infection in surgical patients.

METHODS

In this nationwide retrospective cohort study in 680 American College of Surgeons National Surgical Quality Improvement Program participating sites across the United States, the occurrence of C. difficile infection within 30 days postoperatively between different BMI groups was compared. All American College of Surgeons National Surgical Quality Improvement Program patients between 2015 and 2016 were classified as underweight, normal-weight, overweight, or obese class I-III if their BMI was less than 18.5, 18.5 to 25, 25 to 30, 30 to 35, 35 to 40 or greater than 40, respectively.

RESULTS

A total of 1,426,807 patients were included; median age was 58 years, 43.4% were male, and 82.9% were white. The postoperative incidence of C. difficile infection was 0.42% overall: 1.11%, 0.56%, 0.39%, 0.35%, 0.33% and 0.36% from the lowest to the highest BMI group, respectively (p < 0.001 for trend). In univariate then multivariable logistic regression analyses, adjusting for patient demographics (e.g., age, sex), comorbidities (e.g., diabetes, systemic sepsis, immunosuppression), preoperative laboratory values (e.g., albumin, white blood cell count), procedure complexity (work relative unit as a proxy) and procedure characteristics (e.g., emergency, type of surgery [general, vascular, other]), compared with patients with normal BMI, high BMI was inversely and incrementally correlated with the postoperative occurrence of C. difficile infection. The underweight were at increased risk (odds ratio, 1.15 [1.00-1.32]) while the class III obese were at the lowest risk (odds ratio, 0.73 [0.65-0.81]).

CONCLUSION

In this nationwide retrospective cohort study, obesity is independently and in a stepwise fashion associated with a decreased risk of postoperative C. difficile infection. Further studies are warranted to explore the potential and unexpected association.

LEVEL OF EVIDENCE

Prognostic/Epidemiologic, Level IV.

Plasma interleukin-1 alpha and beta, tumor necrosis factor-alpha, and lipopolysaccharide concentrations during pulmonary exacerbations of cystic fibrosis

Earlier studies have reported the presence of interleukin-1 (IL-1) and tumor necrosis factor (TNF) in the plasma of patients with cystic fibrosis (CF), but the results have been inconsistent. To investigate the relationships among plasma IL-1 alpha, IL-1 beta, TNF, lipopolysaccharide (LPS), and clinical status, measurements were made before and after 14 days of intravenous antibiotic therapy in 13 patients with CF. In addition, whole blood cytokine production rates were measured in 18 hr cultures stimulated with 10 micrograms/mL LPS or sterile saline (control). On admission, patients with CF had significantly greater plasma levels of LPS and IL-1 alpha compared with 20 healthy adult controls. In response to antibiotic therapy, the patients had statistically significant increases in weight, oxygen saturation, chest radiograph score, and forced expiratory volume in 1 second. They had significant decreases in pulse rate, residual volume/total lung capacity ratio, white blood count, neutrophil count, LPS concentration, and resting energy expenditure per kg body weight. There were no significant changes in the plasma concentrations of IL-1 alpha, IL-1 beta, or TNF and no significant changes in the basal or stimulated whole blood production rates of IL-1 alpha, IL-1 beta, or TNF. The immunological variables did not correlate significantly with clinical measurements of severity or the presence of fever. It is likely that in CF local pulmonary effects of cytokines are of more pathophysiologic significance than systemic effects.