Background:

The systemic response of the organism, in defense against the aggressor agent, generates acute catabolic response, which leads to deterioration of the nutritional status.

Objective:

Compare the usefulness of the body mass index (BMI) and the CONUT scale to determine the severity in abdominal sepsis.

Methods:

Retrospective, descriptive, cross-sectional study in patients with diagnosis of abdominal sepsis, from April 2016 to February 2017.

Results:

We included 153 cases (61 female and 92 male); mean age of 47.44 years, the main organ causing abdominal sepsis was the appendix 43%. Mortality of 15%. An average BMI of 27.31, CONUT score of 5.5, was obtained. The findings, subjected to the Mann-Whitney u test, showed statistical significance when evaluating BMI against SOFA (p = 0.025); no significance was found when evaluating the BMI against APACHE II (p = 0.322), nor against mortality (p = 0.646). Regarding CONUT, significance was found when comparing against APACHE II, SOFA and mortality (p = 0.002, p = 0.001 and p = 0.007, respectively).

Conclusions:

The level of malnutrition determined by CONUT is related to the severity determined by APACHE II, SOFA and mortality. BMI is not related to severity by APACHE II or mortality; although it does seem to relate to the severity evaluated by the SOFA scale.