THE NEC CONUNDRUM

1
THE NEC CONUNDRUM
2
NEC , WHAT IS IT?

• 1888 ? Possible first description of NEC
• 1943 ? Possible first NEC operation
• 1964 clinical and radiological characteristics of
  NEC officially described
• Today 25000 cases per annum in USA

3
THE FIRST OF THE CONUNDRUMS.

• WHAT ACTUALLY CAUSES IT?

4

• PREMS AND LBW
• INTESTINAL ISCHAEMIA INFECTION
• BABY FACTORS
• PULMONARY IMMATURITY
• PDA
• LIVER IMMATURITY
• IMMUNOLOGICAL DEFICIENCIES
• COMPLEMENT SYSTEM COMPONENTS
• IMMUNOGLOBULIN DEFICIENCIES
• POLYMORPHONUCLEAR LEUKOCYTES
• T-CELL AND CYTOKINE PRODUCTION LIMITED

5

• EXOGENOUS FACTORS
• BIRTH ASPHYXIA
• UMBILICAL ARTERY CANNULATION
• EXCHANGE TRANSFUSIONS
• FEEDS FORMULA AND BREAST MILK
• Changing trends in NEC. JL Grosfeld. Ann Surg Vol
  214 No 3 Sept 1991

6
SO YOU WOULD THINK THIS IS SOMETHING PREVENTABLE

• Prophylactic antibiotics in prems and LBW
• Prophylactic IgA and IgG
• Rapid vs. slow rate of advancement feeds
• Arginine
• 1. Cochrane Library, Neonatal Review Group
• 2. The Fear Of NEC versus achieving optimal
  growth in preterm infants-an opinion. O
  Flidel-Rimon et al. Acta Paediatrica
  2006951341-44
• Whats new?
• Probiotics
• Probiotics for prevention of NEC in preterm
  neonates with VLBW a systematic review of RCTs.
  G Deshpande et al. Lancet 20073691614-20.

7
How do we diagnose it?

• Abdominal distension 100
• Bilious vomiting 75
• Guaiac positive stools 60
• Diarrhoea 20
• Lethargy
• Temperature instability
• Apnoea
• Shock

8
STAGING

• BELL CRITERIA 1978, MODIFIED IN 1986 BY WALSH.
• STAGE I suspected NEC
• STAGE II definite NEC
• STAGE III advanced NEC

9
MANAGEMENT

• Stage I II usually medically, non-operatively
• Stage III often surgically. Usually directed at
  complications of NEC

10
INDICATIONS FOR SURGERY

• ABSOLUTE free intraperitoneal air
• RELATIVE portal vein air
• failed medical management

11
CONUNDRUMS CONTINUE

• Radiological signs have a high specificity, but
  low sensitivity.
• NEC surgical decision making. AL Tam. JPS Dec 3
  2002
• WHATS NEW?

12
ABDOMINAL ULTRASOUND

• Intramural air
• Portal venous air
• Free intraperitoneal air
• Intra-abdominal fluid
• Bowel wall thickness
• Bowel wall perfusion
• 1.Necrotizing Enterocolitis Review of
  State-of-the-Art Imaging Findings with Pathologic
  Correlation. M Epelman et al. Radiographics
  200727 287-305.
• 2. Correlation of sonographic findings and
  outcome in necrotizing enterocolitis. S Cicero.
  Paediatric Radiology, Volume 37, Number 3, March
  2007 , pg. 274-282(9)

13
SURGICAL OPTIONS

• Peritoneal Drainage
• Laparotomy
• Resection and anastomosis
• Resection and stoma
• Multiple resections with clip and drop back
• Patch, drain and wait
• Exploratory laparotomy and closure

14
PERITONEAL DRAINAGE

• Introduced in the late 1970s, specifically for
  VLBW babies, prior to laparotomy.
• Trend for peritoneal drainage to become primary
  surgical procedure.
• Dimmitt 2001 salvage laparotomy did not appear
  beneficial.
• Demestre 2002 prospective study of peritoneal
  drainage, 86 improved, 64 survived without need
  of laparotomy.
• Blakely 2005 prospective cohort study of NEC III
  showed no difference in survival rate between
  drainage and laparotomy.
• Moss 2006 The type of operation performed for
  perforated necrotizing enterocolitis does not
  influence survival or other clinically important
  early outcomes in preterm infants.
• Blakely 2006 results favored laparotomy over
  peritoneal drainage
• Cochrane review currently under way

15
CONCLUSION

• Etiology not fully defined
• Prevention no definitive strategy
• Management
• Diagnosis - clinical
• Type of intervention medical vs surgical