To analyze the incidence and factors associated with constipation in critically ill children.

We performed a prospective observational study that included children admitted to the pediatric intensive care unit for more than 3 days. Constipation was defined as more than 3 days without a bowel movement. Relationships between constipation and demographic data; clinical severity score; use of mechanical ventilation, use of vasoconstrictors, sedatives, and muscle relaxants; nutritional data; electrolyte disturbances; and clinical course were analyzed.

Constipation developed in 46.7% of the 150 patients studied (mean age, 34.3 ± 7.1 months). It was most common in postoperative, older, and higher-body-weight patients, and in those with fecal continence (P < .01). Compared with patients without constipation, patients with constipation had higher severity scores and more frequently received midazolam, fentanyl, muscle relaxants, and inotropic support (P < .05). Patients with constipation also started nutrition later and with a lower volume of nutrition (P < .01). There were no between-group differences in mortality or length of pediatric intensive care unit stay. In multivariate analysis, independent factors associated with constipation were body weight (OR, 1.08; 95% CI, 1.03-1.13), Pediatric Index of Mortality 2 score (OR, 1.05; 95% CI, 1.02-1.09), admission after surgery (OR, 7.64; 95% CI, 2.56-22.81), and treatment with vasoconstrictors (OR, 10.28; 95% CI, 3.53-29.93).

Constipation is common in critically ill children. Body weight, Pediatric Index of Mortality 2 clinical severity score, admission after surgery, and the need for vasoconstrictor therapy are major independent risk factors associated with constipation.