Overview
Definition:
Necrotizing Enterocolitis (NEC) is a devastating gastrointestinal emergency primarily affecting premature infants, characterized by intestinal inflammation, ischemia, and necrosis
Surgical intervention is often required for advanced NEC.
Epidemiology:
NEC is the most common non-congenital surgical emergency in neonates, with an incidence of 1-4 per 1000 live births, significantly higher in very low birth weight infants (<1000g)
Mortality rates can exceed 30% in surgically treated cases.
Clinical Significance:
Early recognition of NEC and timely surgical decision-making are critical for improving survival and reducing long-term morbidity
Effective ostomy care is paramount for patient recovery and preventing complications post-surgery.
Surgical Indications
Indications Medical Refractory:
Failure to improve despite maximal medical management (bowel rest, antibiotics, nasogastric decompression, fluid resuscitation) for 24-48 hours
Persistent abdominal distension, bloody stools, and hemodynamic instability.
Indications Perforation:
Radiographic evidence of pneumoperitoneum (free air in the abdominal cavity) on plain abdominal X-ray is an absolute indication for immediate surgery.
Indications Abdominal Wall Signs:
Abdominal wall erythema, edema, induration, or a rigid abdomen suggest transmural bowel necrosis and perforation, necessitating surgical exploration.
Indications Other Deterioration:
Progressive metabolic acidosis unresponsive to treatment, worsening thrombocytopenia, coagulopathy, or signs of sepsis and shock despite intensive medical therapy.
Diagnostic Approach
History Taking:
Detailed feeding history (prematurity, formula vs
breast milk, timing of feeds)
Onset and progression of symptoms
Previous episodes of NEC
Maternal and birth history.
Physical Examination:
Abdominal assessment: distension, tenderness, guarding, rigidity, decreased bowel sounds or absent sounds
Presence of abdominal wall discoloration (erythema, purpura, cyanosis)
Rectal examination for blood
Vital signs: tachycardia, hypotension, hypothermia/fever, respiratory distress.
Investigations:
Abdominal X-ray: initial imaging of choice, looking for bowel distension, thickened bowel wall, pneumatosis intestinalis, portal venous gas, and free air
Ultrasound: can be useful for detecting free fluid and ascites
Blood tests: Complete Blood Count (CBC) for leukocytosis/leukopenia, thrombocytopenia
electrolytes, arterial blood gases (ABGs) for acidosis
C-reactive protein (CRP) for inflammation
coagulation profile.
Differential Diagnosis:
Other causes of abdominal distension and feeding intolerance in neonates, including prematurity-related issues (immature gut motility), sepsis, congenital intestinal anomalies (e.g., malrotation with volvulus, Hirschsprung disease), intussusception, or surgical abdomen from other causes.
Surgical Management
Initial Surgical Steps:
Laparotomy or limited enterotomy with initial decompression of distended bowel segments
Lavage of the peritoneal cavity if contaminated
Identification of necrotic or perforated bowel segments.
Resection And Anastomosis:
Resection of all frankly necrotic or perforated bowel
Decision regarding primary anastomosis versus diversion with ostomy is based on the extent of involvement, infant's stability, and surgeon's judgment
Limited resection is preferred to preserve as much bowel as possible.
Diversion Ostomy:
Creation of a stoma (ileostomy or colostomy) is common, especially in critically ill infants or when the distal bowel is compromised
This diverts fecal stream and allows the defunctionalized bowel to heal.
Secondary Anastomosis:
If an ostomy is created, a plan for eventual stoma reversal and intestinal anastomosis is made, typically after the infant has recovered and gained weight.
Ostomy Care
Stoma Assessment:
Regular visual inspection of the stoma: color (should be pink to red), moisture, and any signs of retraction, prolapse, stenosis, or ischemia
Assess surrounding skin for irritation, erythema, or breakdown.
Ostomy Appliance Selection:
Appropriate ostomy pouching system is crucial
Options include one-piece or two-piece systems
Skin barrier (wafer) should be cut to fit snugly around the stoma without constricting it
Convexity may be needed for retracted stomas.
Skin Care:
Clean the peristomal skin gently with warm water or a mild, non-alcoholic cleanser
Dry the skin thoroughly
Apply a skin barrier paste or ring as needed to fill uneven skin contours
Protect the skin from stoma output with barrier creams or sprays.
Output Management:
Monitor stoma output: consistency, volume, and any signs of malabsorption
Fluid and electrolyte balance must be carefully managed, especially with high-output ileostomies
Nutritional support, including parenteral or enteral feeding, is essential
Education of parents/caregivers on stoma care is vital for home management.
Complications
Surgical Complications:
Intra-abdominal abscess, wound infection, anastomotic leak, adhesions, bowel obstruction, stomal complications (retraction, prolapse, stenosis, fistula), short bowel syndrome.
Long Term Sequelae:
Growth failure, malabsorption, neurodevelopmental delays, increased risk of gastrointestinal infections, increased incidence of surgical re-operations, electrolyte imbalances.
Prevention And Monitoring:
Strict aseptic technique during surgery and stoma management
Early recognition and management of stomal issues
Aggressive nutritional support
Close monitoring of fluid and electrolyte status
Serial abdominal examinations to detect early signs of recurrence or complications.
Key Points
Exam Focus:
Absolute surgical indication: pneumoperitoneum
Key decision: resection vs
diversion
Ostomy characteristics (color, moisture)
Peristomal skin integrity is crucial.
Clinical Pearls:
When in doubt, explore! Preserve bowel length whenever possible
Timely ostomy creation can be life-saving
Parental education is a core component of ostomy care.
Common Mistakes:
Delaying surgery in medically refractory NEC
Inadequate bowel resection
Poorly fitted ostomy appliances leading to skin breakdown
Underestimating fluid and electrolyte losses from stomas.