Today, we’re examining a clinical case of a 2-week-old baby girl born at 28 weeks via spontaneous vaginal delivery who is being evaluated in the neonatal intensive care unit (NICU) for low blood pressure. What’s the next step in the baby’s care?
A 2-week-old baby girl born at 28 weeks via spontaneous vaginal delivery is being evaluated in the neonatal intensive care unit (NICU) for low blood pressure. The pregnancy was uncomplicated, and the mother took prenatal vitamins throughout. At birth, the baby weighed 1.7 kg and had been progressing well in the NICU, tolerating enteral feeds. Today, she appears lethargic and has had blood in the stool. Temperature is 100.3°F (38 °C), heart rate is 155/min, respiratory rate is 35/min, and blood pressure is 60/32 mmHg. The patient is sleeping but can be aroused and is moving all four extremities. Exam is notable for decreased bowel sounds, diffuse abdominal distention, and generalized tenderness to palpation without rebound or guarding. Abdominal radiographs are obtained which reveal a small area of pneumatosis intestinalis without evidence of pneumoperitoneum.
Given the most likely diagnosis, which of the following is the most appropriate next step in management?
A. Continue enteral feeds and administer IV fluids
B. Continue enteral feeds, gastric decompression via orogastric tube, and administer IV fluids
C. Hold enteral feeds, gastric decompression via an orogastric tube, administer IV fluids and IV antibiotics
D. Emergent surgical consultation for exploratory laparotomy
E. Emergent interventional radiology consultation for peritoneal drain placement
Scroll down for the correct answer!
The correct answer to today’s USMLE® Step 2 Question is…
C. Hold enteral feeds, gastric decompression via an orogastric tube, administer IV fluids and IV antibiotics
Correct: See Main Explanation.
Incorrect Answer Explanations
A. Continue enteral feeds and administer IV fluids
Incorrect: This patient with a change in feeding tolerance and hematochezia who is found to have pneumatosis intestinalis can be diagnosed with necrotizing enterocolitis. Enteral feeds should be held and treatment should include gastric decompression via an orogastric tube, IV fluids which can improve the patient’s blood pressure, and antibiotics.
B. Continue enteral feeds, gastric decompression via orogastric tube, and administer IV fluids
Incorrect: When necrotizing enterocolitis is diagnosed, enteral feeds should be held and gastric decompression should be initiated, usually via an orogastric tube, and IV fluids and antibiotics should also be given.
D. Emergent surgical consultation for exploratory laparotomy
Incorrect: Surgical intervention for necrotizing enterocolitis occurs in up to 50% of patients. Pneumoperitoneum or a paracentesis showing enteric contents are absolute indications for surgical intervention. If the patient appears unstable and has extensive pneumatosis, surgery should also be considered. This patient appears stable and has a small amount of pneumatosis; therefore, medical management is more appropriate.
E. Emergent interventional radiology consultation for peritoneal drain placement
Incorrect: In patients who have necrotizing enterocolitis and are unstable with evidence of hollow viscus perforation, a primary peritoneal drain placement can be performed at the bedside. A peritoneal drain serves as a temporary measure, as up to 75% of patients end up requiring definitive surgery. It is not necessary for this patient who has no evidence of perforation.
Main Explanation
This premature infant in the NICU with low birth weight presents with a change in feeding tolerance, bloody stools, abdominal pain and distension, and an abdominal x-ray showing pneumatosis intestinalis. These findings are consistent with necrotizing enterocolitis (NEC), and medical management alone is the appropriate initial management for this patient who appears stable without evidence of severe disease or pneumoperitoneum on abdominal x-ray. Medical management consists of withholding enteral feedings, gastric decompression, administering intravenous fluid and intravenous broad-spectrum antibiotics, and obtaining central intravenous access (often with a peripherally inserted central catheter).
Patients diagnosed with necrotizing enterocolitis should be evaluated for hemodynamic stability or instability and severity of symptoms and findings on abdominal x-rays. This patient is hypotensive, but this may respond to initial IV fluids and there are no findings of peritonitis on exam, nor does the abdominal film show evidence of pneumoperitoneum. Therefore, he does not require emergent surgical consultation at this time.
There is no standard duration for antimicrobial therapy for necrotizing enterocolitis, but treatment typically ranges from 7 to 14 days. Similarly, there are no standard antimicrobial agents used to treat NEC, but therapy often initially includes broad-spectrum antibiotics to cover gram-negative, gram-positive, and anaerobic bacteria. Surgery is reserved for unstable patients with pneumoperitoneum or a paracentesis consistent with enteric contents, or for those patients who deteriorate clinically with medical management.
Major Takeaway
In patients with necrotizing enterocolitis (NEC) who have no evidence of perforation or peritonitis and appear stable, medical management is the appropriate initial step. This consists of holding enteral feeds, starting gastric decompression, and beginning IV fluids and antibiotics. Surgery should be consulted, but surgery should be reserved for unstable patients, those with evidence of perforation of peritonitis, or for patients who deteriorate despite medical management.
Want to learn more about this topic?
Watch the Osmosis video: Necrotizing enterocolitis: Clinical sciences
References
- Neu J, Walker WA. Necrotizing enterocolitis. N Engl J Med. 2011 Jan 20;364(3):255-64. doi: 10.1056/NEJMra1005408. PMID: 21247316; PMCID: PMC3628622.
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