Necrotizing Enterocolitis

Question 1

What is the pathophysiology of NEC?

Answer 1

inflammation of the intestine leading to bacterial invasion causing cellular damage and cellular death and necrosis of the colon and intestine

• ischemia –> necrosis –> perforation

Question 2

When is necrotizing enterocolitis most likely to affect preterm neonates?

Answer 2

at 2-3 weeks of life, especially when nearing full feeds

Question 3

What are the 3 most common risk factors for the development of necrotizing enterocolitis?

Answer 3

prematurity, low birth weight, formula feeding

• high osmotic-strength formula

Question 4

What age group is most at risk for developing necrotizing enterocolitis?

Answer 4

Premature VLBW (< 1500g) children born < 32 weeks

• nearly 90%
• 5x higher incidence in ELBW (<1000g) children born <28 weeks

Question 5

What percentage of premature children are affected and what is the overall mortality rate?

Answer 5

• affects 2-5% of all premature neonates
• mortality = 10-50%

Question 6

What are the typical signs and symptoms (4 major) of necrotizing enterocolitis?

Answer 6

• lethargy
• poor appetite/feeding intolerance
• abdominal distension
• bloody stool/vomiting/diarrhea

overall symptoms are NONSPECIFIC

Question 7

What is the single most important test to make the diagnosis of necrotizing enterocolitis?

What are 3 imaging findings that, while rare, would help make the diagnosis more likely?

Answer 7

ABDOMINAL PLAIN FILM (AP and Left Lateral Decubitus)

Findings: pneumatosis intestinalis, portal venous air, dilated loops of bowel

Question 8

How often should abdominal imaging be obtained in a patient with necrotizing enterocolitis?

Answer 8

Serially every 6 hours until definitive treatment has occurred

Question 9

Per Dr. Gurung, what are three (3) common lab values seen in patients with necrotizing enterocolitis?

Answer 9

1. hyponatremia
2. thrombocytopenia
3. acidosis (inc. lactate)

Question 10

What are the first 3 steps of treatment for a patient with necrotizing enterocolitis?

Answer 10

1. NPO with TPN support
2. NG tube for bowel decompression
3. broad-spectrum antibiotics (Amp/Gent/Metro or Clinda)

Question 11

How long should patients receive antibiotics and TPN following surgery for necrotizing enterocolitis?

Answer 11

2 weeks

Question 12

What is the difference between Stage 1, Stage 2, and Stage 3 of necrotizing enterocolitis?

Answer 12

Stage 1 = bowel well thickening
Stage 2 = bowel wall air (pneumatosis)
Stage 3 = bowel wall perforation

Stage 1 and 2 = NPO and Abx
- S1 - 3-5 days
- S2 - 10-14 days
Stage 3 = surgery

Question 13

How many days should patients with Stage 1 and Stage 2 necrotizing enterocolitis receive antibiotics?

Answer 13

Stage 1 = 3-5 days
Stage 2 = 10-14 days

Question 14

What are 5 common complications of necrotizing enterocolitis? (LINSS)

Answer 14

• liver failure (prolonged TPN)
• strictures/adhesions
• small bowel syndrome
• nutritional deficiencies
• intestinal failure

Question 15

Do breastfed premature infants have a lower or higher rate of necrotizing enterocolitis?

Answer 15

LOWER

Question 16

What staging criteria is used for necrotizing enterocolitis?

Answer 16

Bell’s Criteria

Question 17

What are the stages of Modified Bell’s Criteria? (I-III)

Answer 17

I = normal dilation, mild ileus

IIa = intestinal dilation, pneumatosis, ileus
IIb = IIa + ascites

IIIa = same as IIb
IIIb = IIIa + ascites AND pneumoperitoneum