Clinical Pharmacy Specialist Texas Children's Hospital Houston, Texas, United States
Abstract: Objective Necrotizing enterocolitis (NEC) is a serious inflammatory gastrointestinal disease resulting from a compromised gastrointestinal tract breached by bacteria. NEC has been described in full-term infants with significant risk factors including congenital heart disease (CHD). CHD patients with NEC were found to have higher mortality and longer length of stay, especially in the setting of cyanotic heart disease. Ideal empiric antibiotic therapy should target gram-positive, gram-negative, and anaerobic pathogens as no specific organism can be considered causative in most cases of NEC. Variation continues in antibiotic therapy for NEC with scarce evidence in CHD, as well as variation in duration of treatment, usually 7 to 14 days. The purpose of the study is to describe antibiotic usage for NEC in patients admitted to the cardiac intensive care unit (CICU).
Methods A single-center retrospective study was conducted of patients admitted to the CICU at Texas Children’s Hospital between July 1, 2014 to July 1, 2021. Patients were included if they had a gestational age of 37 weeks or greater and were less than 3 months postmenstrual age with a first-time diagnosis of NEC and received at least 48 hours of antibiotics. Patient characteristics collected consisted of history of asplenia, cardiac lesion characterization, cardiac surgical history, nutrition history, blood transfusions, and history of antibiotics, gastric acid suppressants, vasoactive infusion score (VIS), and prostaglandin E1 use. Description of antibiotics were reported as the antibiotic dose and duration. Outcomes observed were in-hospital mortality, length of stay, and treatment failure defined as any bowel operation required after medical treatment or recurrent NEC within 7 days after completion of initial antibiotic course.
Result There were 56 patients included with majority being male with a median (IQR) postnatal age of 23.5 (9.3 42.5) days at NEC diagnosis. Cyanotic lesions were present in 40 (71.4%) and prostaglandin E1 was used in 5 (8.9%) patients. There were 17 (30.4%) patients that underwent cardiac surgery prior to NEC with most patients having a STAT score of 5. Functional or anatomical asplenia was noted in 5 (8.9%) patients, 8 (14.2%) patients received blood transfusions within 24 hours, and 19 (33.69%) of patients were receiving vasoactives with median (IQR) VIS of 2 (0-5). In the 31 patients who received enteral feeds prior to NEC diagnosis, the median (IQR) of largest volume of feeds was 128 (91.1-139.5) mL/kg/day. Thirty-four (60.7%) patients were exposed to antibiotics prior to NEC diagnosis with 9 (26.5%) patients requiring antibiotic treatment for greater than 48 hours and 23 (67.6%) for prophylaxis. The most common antibiotic regimen used was ampicillin plus gentamicin plus metronidazole (33.9%) and the median (IQR) duration of therapy was 7 (5-7) days. Treatment failure occurred in 4 (7.1%) patients due to recurrent NEC within 7 days of completion of antibiotics. Median (IQR) length of stay was 92.5 (48-137) days and 3 (5.4%) were documented with in-hospital mortality.
Conclusion This study described a multitude of antibiotic regimens used for necrotizing enterocolitis in congenital heart patients with low incidences of treatment failure.
