**9.1 Medical management**

The principles are as follows: (1) bowel decompression and rest, (2) parenteral hydration and nutrition, (3) respiratory and cardiovascular support, (4) antibiotic therapy, (5) general supportive care, (6) fluid resuscitation, and (7) serial close laboratory monitoring and radiologic surveillance. The focus is on limiting the progression of the disease. Intermittent or continuous nasogastric suction is done for bowel decompression, TPN is provided to ensure nutrition, and fluid is replaced to correct third space losses. Adequate cardiorespiratory support is of paramount value, and hematologic anomalies, such as DIC, anemia, and thrombocytopenia, are promptly corrected. Metabolic abnormalities, such as metabolic acidosis, hyponatremia, and hyper- or hypoglycemia, are appropriately treated. Even though an infectious agent has not been identified or attributed to NEC, antibiotics are routinely used in its treatment. Observational data reveal that 20–30% cases of NEC have bacteremia, and pathogenic bacteria are recovered from pathologic specimens and peritoneal fluid. Epidemic outbreaks of NEC are common, and the clinical picture improves with antibiotics. The efficacy of antibiotic agents is documented in experimental animal models for NEC. The commonly used empiric broad-spectrum antibiotic combinations are as follows: ampicillin gentamicin (or amikacin), ampicillin, gentamicin (or amikacin) and clindamycin or ampicillin, cefotaxime, and metronidazole. Ceftazidime is an alternative choice for cefotaxime. Other antibiotic combinations are tazobactam and gentamicin (or amikacin); vancomycin, piperacillin-tazobactam, and gentamicin; and meropenem and vancomycin if methicillin-resistant staphylococcus or ampicillin-resistant enterococcus infections are suspected. Amikacin may be used in centers with significant gentamicin resistance. Metronidazole or clindamycin is added to cover anaerobic bacteria, especially in cases where infant is fed orally before NEC supervenes.

Evaluation of progression of the disease is important in order to take appropriate and timely steps to avoid further damage to the bowel. Serial laboratory monitoring is routinely performed. At diagnosis stool for guaiac test, complete blood and differential neutrophil counts, blood culture, CSF study if indicated, C-reactive protein, platelet count, serum electrolytes, pH, creatinine, blood urea nitrogen, and acid-base studies are obtained and monitored q 12 or 24 h or more frequently


### **Table 4.**

*Management principles of NEC [65].*

if needed. In addition, arterial blood gas values are measured and repeated every 4–6–12 h as per the severity of respiratory decompensation. Serial lactate levels are helpful in monitoring progression of the necrotic process and assessing systemic status. Worsening or persistent metabolic acidosis and persistent hyperglycemia or thrombocytopenia are poor prognostic signs. Improvement in metabolic acidosis is a positive prognostic sign but may be misleading if blood circulation to the necrotic bowel is completely severed and the generated lactic acid cannot enter the circulation. Blood in stools is not predictive of resolution or outcome. Radiographic monitoring is done with abdominal radiograph performed in supine position during the initial phase of illness. A lateral decubitus view is simultaneously obtained with the infant's left side down to visualize the presence of free air over the liver. It should be repeated q 6–12 h as per the severity and progression of the disease and when improvement is obtained less frequently. In the initial stages q 4–6 h may be appropriate and advisable. Supine cross-table lateral view may be done to visualize layering of free air under umbilical area if patient is too sick to move or put in a decubitus position (**Figure 2**). Radiography is discontinued when pneumatosis resolves and bowel gas pattern normalizes.
