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Necrotising Enterocolitis 421
Ethical Issues Evidence-Based Research
Many of the ethical issues involved in the treatment of NEC in devel- Table 70.3 presents a study that compares primary peritoneal drainage
oping nations relate to the challenge of proper and efficient allocation and laparotomy in infants with perforated NEC. Table 70.4 revisits
of scarce resources. The survival rate of the disease often relies on indications for surgery in NEC.
prolonged, intensive, and costly ICU care, so the question arises as to Table 70.4: Evidence-based research
the advisability of expending precious time and money on aggressive
interventions only to yield poor survival rates. Additionally, a high Title Indications for operation in necrotizing enterocolitis revisited
percentage of the survivors of NEC in these regions end up with long- Authors Kosloske AM
term complications that cannot be adequately managed, which leads to Institution Department of Surgery, Ohio State University College of
further morbidity and mortality. These issues must be evaluated based Medicine, Columbus, Ohio, USA: University of New Mexico
on the resources of each individual region. Hospital, Albuquerque, New Mexico, USA
Reference J Pediat Surg 1994; 29(5):663–666
Table 70.3: Evidence-based research.
Problem Evaluation of 12 criteria as predictors of intestinal gangrene
Title Laparotomy versus peritoneal drainage for necrotizing in patients with necrotising enterocolitis.
enterocolitis and drainage
Comparison/ A series of 147 infants treated for NEC was analysed
Authors Moss RL, Dimmitt RA, Barnhart DC, Sylvester KG, Brown control to evaluate the accuracy of 12 proposed findings as
RL, Powell DM, et al. (quality of indicators of intestinal gangrene. These findings included
Institution Yale University School of Medicine, New Haven, evidence) pneumoperitoneum, portal venous gas, fixed loop,
fixed abdominal mass, erythema of abdomen, positive
Connecticut, USA; among others
paracentesis, severe pneumatosis, clinical deterioration,
Reference N Engl J Med 2006; 354(21):2225–2234 low platelet count, severe gastrointestinal haemorrhage,
abdominal tenderness, and gasless abdomen/ascites.
Problem Evaluation of primary peritoneal drainage versus laparotomy Operation was performed (usually resection and
in infants with perforated necrotising enterocolitis. enterostomy) for evidence of intestinal perforation or
Intervention Laparotomy, primary peritoneal drainage. gangrene. Intestinal gangrene was documented for all infants
by either operation, autopsy, or radiographic findings of
Comparison/ The population was 117 preterm infants (delivered before pneumoperitoneum or intestinal stricture.
control 34 weeks of gestation) with birth weights less than 1,500 g Outcome/ The findings of pneumoperitoneum, portal venous gas, and
(quality of and perforated NEC at 15 paediatric centres randomised effect positive paracentesis each had specificities and positive
to undergo primary peritoneal drainage or laparotomy with
evidence) predictive values approaching 100% with a prevalence
bowel resection. Postoperative care was standardised. The
primary outcome was survival at 90 days postoperatively. greater than 10%. Pneumoperitoneum had a prevalence of
Secondary outcomes included dependence on parenteral 48%. The findings of a “fixed-loop,” palpable abdominal mass
nutrition 90 days postoperatively and length of hospital and erythema of the abdominal wall also had specificities
stay. and positive predictive values approaching 100% but had
a prevalence below 10%. Severe pneumatosis had a
Outcome/ At 90 days postoperatively, there was no significant specificity of 91%, and positive predictive value of 94% and
effect difference in mortality between the drainage and a prevalence of 20%. The remaining five findings all had
laparotomy groups (34.5% versus 35.5%, P = 0.92). specificities below 90%, positive predictive values below
There was also no significant difference in dependence on 80%, and prevalence ranging between 2% and 28%.
parental nutrition (47.2 % versus 40.0%, P = 0.53) or mean
length of stay (126±58 days and 116±56 days, respectively; Historical Although no single finding is particularly sensitive for
P = 0.43). significance/ intestinal necrosis, the findings of pneumoperitoneum, portal
comments venous gas, positive paracentesis, fixed-loop sign, palpable
Historical This randomised, prospective trial suggests that treatment abdominal mass, and erythema of the abdominal wall all
significance/ with primary peritoneal drainage and laparotomy with bowel had specificities approaching 100% and may be used as an
comments resection are comparably efficacious in the treatment of indication for surgical intervention. Severe pneumatosis was
perforated NEC. Mortality in this patient population was also found to have a fair specificity for intestinal necrosis. The
found to be ~35%. Although 5 out of the 30 patients (16.7%) remaining findings had poor specificity and positive predictive
in the primary peritoneal drainage group subsequently value. Although seven of these findings were highly specific
required laparotomy for clinical deterioration, drainage for intestinal necrosis, the prevalence of these signs were
obviated the need for laparotomy in the remaining infants low. As such, the absence of these findings cannot rule out
without any discernible increase in mortality. intestinal necrosis, and the decision for surgical intervention
will often rely on clinical judgment of the managing surgeon.

Key Summary Points

1. Necrotising enterocolitis occurs in 1–3 infants per 1,000 live births. 9. Pneumoperitoneum is an absolute indication for surgical
intervention; relative indications include a fixed-loop on
2. Ninety percent of cases occur in premature infants. abdominal radiographs, an abdominal mass or erythema of the
3. Mortality rates range between 15% and 30%. abdominal wall on physical exam, positive paracentesis, and
4. The aetiology and pathophysiology of the disease is not well whether there is little or no evidence of clinical improvement.
understood. 10. Primary peritoneal drainage and laparotomy are comparable
5. Prematurity as well as timing and content of gastrointestinal treatments for perforated necrotising enterocolitis.
feeding are the most consistent risk factors associated with NEC. 11. Surgical goals focus on resection of frankly necrotic bowel with
6. Human breast milk has been shown to be protective against an effort to preserve intestinal length.
the development of NEC. 12. Advances in intensive care unit facilities in developed nations
7. NEC presents with both specific gastrointestinal signs have translated into improved survival in patients with NEC.
of vomiting, distention, and blood per rectum as well as 13. More aggressive surgical protocols may improve survival in
nonspecific signs of haemodynamic instability. developing nations that lack modern intensive care unit facilities.
8. Abdominal radiography is the primary imaging tool in
establishing the diagnosis of necrotising enterocolitis.