Diarrhea in intensive care: diagnosis and treatment

Role of FODMAP content in enteral nutrition-associated diarrhea

Gastrointestinal symptoms including diarrhea are common complications of enteral nutrition (EN); however, the cause is unclear. Mode of EN delivery that alters digestion and possibly absorption is suggested to contribute to the high incidence of diarrhea; however, enteral formula is frequently blamed. Most research has focused on fiber-supplemented EN, with a meta-analysis showing that fiber reduces the incidence of diarrhea in non-intensive care unit studies. Other hypotheses include formula osmolality and FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) content. FODMAPs are poorly absorbed short-chain carbohydrates that exert an osmotic effect. Dietary FODMAPs have been shown to reduce gastrointestinal symptoms, including diarrhea, in those with irritable bowel syndrome and, given a high-enough dose, will induce a laxative effect in most people. As FODMAPs are commonly added to enteral formula and EN is frequently used as the main source of nutrition, it is reasonable to hypothesize that EN provides more FODMAPs than usual dietary intake and increases risk for developing diarrhea. This hypothesis was assessed through a retrospective study showing that the standard-use enteral formula Isosource 1.5 had a protective effect of developing diarrhea. The only characteristic unique to Isosource 1.5 was the lower FODMAP content as determined through methodologies previously validated for food analysis. Methodologies for application to enteral formulas are currently undergoing formal validation. Once confirmed for application in enteral formula, future directions include FODMAP analysis of specific ingredients to increase understanding of potential problems associated with enteral formula and a randomized, controlled trial investigating the role of formula FODMAP content.

Diarrhoea during enteral nutrition is predicted by the poorly absorbed short-chain carbohydrate (FODMAP) content of the formula

BACKGROUND

Although it is recognized that diarrhoea commonly complicates enteral nutrition, the causes remain unknown.

AIM

To identify factors associated with diarrhoea in patients receiving enteral nutrition with specific attention to formula composition.

METHODS

Medical histories of in-patients receiving enteral nutrition were identified by ICD-10-AM coding and randomly selected from the year 2003 to 2008. Clinical and demographic data were extracted. Formulas were classified according to osmolality, fibre and FODMAP (fermentable oligo-, di- and mono-saccharides and polyols) content.

RESULTS

Formula FODMAP levels ranged from 10.6 to 36.5 g/day. Of 160 patients receiving enteral nutrition, 61% had diarrhoea. Univariate analysis showed diarrhoea was associated with length of stay >21 days (OR 4.2), enteral nutrition duration >11 days (OR 4.0) and antibiotic use (OR 2.1). After adjusting for influencing variables through a logistic regression model, a greater than five-fold reduction in risk of developing diarrhoea was seen in patients initiated on Isosource 1.5 (P = 0.029; estimated OR 0.18). The only characteristic unique to this formula was its FODMAP content, being 47-71% lower than any other formula.

CONCLUSIONS

Length of stay and enteral nutrition duration independently predicted diarrhoea development, while being initiated on a lower FODMAP formula reduced the likelihood of diarrhoea. As retrospective evaluation does not support a cause-effect relationship, an interventional study investigating FODMAPs in enteral formula is indicated.

Role of enteral nutrition in the incidence of diarrhea among hospitalized adult patients

OBJECTIVE

This study examined the risk of diarrhea as a result of providing enteral nutrition in the hospital setting, adjusting for other clinical and therapeutic factors.

METHODS

Adults admitted to a general tertiary care university hospital, in clinical or surgical units, were enrolled in the study between June 2004 and May 2005 and prospectively followed during their hospital stay. For each patient treated with enteral nutrition (n = 302), a comparable non-treated patient from the same ward (who also received antibiotics previously) and was similarly cared for by the same hospital staff was included in the study (n = 302), constituting a double-cohort study. All patients were seen three times per week, on alternating days, until the occurrence of diarrhea or hospital discharge. Cox's regression analyses were applied for adjustments.

RESULTS

The incidence of diarrhea was 18% for patients receiving enteral nutrition and 6% for non-treated patients (P < 0.01). In multivariate analyses, enteral nutrition was independently associated with diarrhea (hazard ratio 2.7, 95% confidence interval 1.6-4.7), even adjusting for age (hazard ratio 1.02, 95% confidence interval 1.00-1.03) and hospitalization during the summer months (hazard ratio 2.4, 95% confidence interval 1.5-3.9). Patients for whom strict adherence to delivery-set washing-and-changing procedures was observed (on >75% of days) presented a lower incidence of diarrhea (6.5% versus 20.3%, P = 0.02; and 5.9% versus 19.8%, P = 0.05, respectively).

CONCLUSION

Providing enteral nutrition to the hospitalized elderly during the summer months is associated with a higher risk of diarrhea. Strategies aimed toward improvement in the quality of enteral nutrition practices should be evaluated to minimize this deleterious clinical outcome.