Thickness of the adductor pollicis muscle: Accuracy in predicting malnutrition and length of intensive care unit stay in critically ill surgical patients: Thickness of the adductor pollicis muscle in surgical critically patients

Abstract

Backgrounds & aims: new techniques for assessment of nutritional status of critically ill and surgical patients have been investigated to overcome inherent limitations of conventional method. The current study aimed to evaluate the ability of thickness of the adductor pollicis muscle (TAPM) in detecting malnutrition and predicting morbidity and mortality in critically ill surgical patients.

Methods: cohort study of adult patients, assessed within the 48 h of admission to the surgical intensive care unit (ICU) of a public hospital. TAPM measurements of the non-dominant hand were performed with patients lying supine. TAPM values lower than the 5th percentile for age and sex were adopted to identify malnutrition. Patients were followed up until discharge for measurement of the following parameters: length of ICU stay, time on mechanical ventilation, length of hospital stay, and hospital mortality.

Results: fifty-nine surgical ICU patients, with mean age of 60.0 ± 17.4 years were included in the current study. There was a positive, weak-to-moderate correlation between TAPM and anthropometric indicators (r = 0.338 to r = 0.579; p < 0.01). The ability of TAPM in identifying patients with malnutrition (diagnosed by global subjective assessment) was assessed by ROC curve analysis, and an area under the ROC curve of 0.611 (95%CI: 0.459-0.762; p = 0.151) was found. TAPM < p5 increased the risk of ICU length of stay >3 days (RR = 2.92; 95%CI 1.09-7.81; p = 0.032). Relative frequencies of malnourished and well-nourished patients according to TAPM were not different between survivors and non-survivors (p = 0.814).

Conclusion: TAPM showed unsatisfactory accuracy in predicting malnutrition. Although TAPM was not a good mortality predictor, reduced TAPM (< p5) values increased the risk of a prolonged ICU stay (>3 days).

Keywords: Anthropometry; Critical care; Intensive care units; Length of stay; Mortality; Nutritional assessment; Thickness of the adductor pollicis muscle.