Necrotising enterocolitis in Paediatric Intensive Care, management guideline (1186)

Objectives

To provide a consistent approach to the diagnosis and management of a patient with necrotising enterocolitis (NEC) within the Paediatric Intensive Care Unit (PICU).

Scope

This guideline is intended for all healthcare professionals caring for infants in the paediatric intensive care unit at the Royal Hospital for Children, Glasgow who present with abdominal concern which is suspicious of NEC. 

Audience

All medical, nursing, dietetic staff caring for infants within PICU should be familiar with this guideline.

Despite substantial advances in the care of infants with congenital heart disease (CHD), necrotising enterocolitis (NEC) remains a significant source if morbidity and mortality (Iannucci, Oster and Mahle, 2013). 

Necrotising enterocolitis (NEC) can be a devastating condition, in which areas of the distal small bowel and proximal colon undergo cell death and in severe cases may be fatal.  Although often associated with preterm infants, 10% of cases occur in term infants (Pickard et al, 2009) and congenital heart disease (CHD) is a recognised risk factor (ref).

The pathophysiology of NEC in infants with CHD is not fully understood (Lau et al, 2018) but mesenteric hypo-perfusion due to the heart defect or the development of low cardiac output state (LCOS) is speculated to result in hypoxia to the intestines.  This in turn results in endothelial inflammation, vascular permeability, release of cytokines, endothelial damage, bacterial translocation, degradation of mucosa and dysbiosis (Burge et al, 2022).

The incidence of NEC was reported to be 2.4% in a multi-centred UK study of children, aged 16 years and under, following cardiac surgery and was estimated to have additional healthcare costs of £16,500 (Brown et al, 2019).  However, incidence figures are higher in cohorts that have only included infants and Schuchardt et al (2013) reported and incidence of 13% in those less than 6 months of age following cardiac surgery. 

A local retrospective 3 year audit carried out from 2018 to 2021 reported an overall NEC incidence of 8.5% in infants <1year of age following cardiac surgery, with a 3.5% incidence of radiologically confirmed NEC with an associated mortality of 40%.  Similar to findings reported by Schuchardt et al (2013) the local audit identified that radiological NEC occurred further out from the original cardiac surgical procedure than milder forms of the condition.  It can only be speculated that this is due to haemodynamic impairment that necessitates a prolonged stay in PICU post-operatively and therefore resulting in an increased risk of severe NEC. The project also identified variability in management of NEC including; the duration of antibiotics, frequency of radiological imaging, days before re-introduction of enteral feeding and the rate advancement of enteral feeds.

Diagnosis

Early symptoms of NEC are often non-specific and difficult to distinguish from other illness such as sepsis and therefore timely diagnosis and management presents a challenge to clinicians. 

Clinical signs and symptoms include:

  • Enteral feed intolerance
  • Abdominal distention
  • Bloody stools
  • Abdominal wall erythema (in severe cases)
  • Septic shock (in severe cases) i.e. increased haemodynamic instability, increase in vasoactive support, pyrexia, elevated CRP.

Suspected diagnosis is confirmed with typical findings on abdominal x-ray, including:

  • Pneumatosis intestinalis
  • +/- Air in the portal vein
  • Pneumoperitoneum (severe cases)

A staging system for NEC was developed by Bell et al (1978) and has been modified by Deitch et al (2023, p2):

Stage

Classification

Clinical Signs

Radiological Signs

I

Suspected Necrotising Enterocolitis

Abdominal distention, bloody stools, emesis, apnoea, lethargy

Ileus/dilation

II
(Definitive)

Proven Necrotising Enterocolitis

Abdominal tenderness +/- metabolic acidosis, thrombocytopenia

Pneumotosis and/or portal venous gas

III
(Definitive)

Advanced Necrotising Enterocolitis

Hypotension, DIC, neutropenia

Pneumoperitoneum

Management options

The goal of treating NEC is to prevent further injury to the mucosal lining of the gastrointestinal tract, halt disease progression, treat any infection and thereby enable gut recovery. 

The management of NEC typically includes the following:

  • Cessation of enteral feeding for several days, often necessitating parenteral nutrition.
  • A course of multiple (often triple) antibiotics to cover both anaerobic and Gram-negative bacteria, with the addition of anti-fungal prophylaxis.
  • Severe cases may require laparotomy +/- resection
  • Provision of supportive care i.e. haemodynamic and respiratory support. 

The evidence base to guide NEC management is sparse and although not specifically for NEC in infants with CHD a systematic review published by Gill et al (2022) concluded that there is insufficient evidence to make recommendations regarding the choice and duration of antibiotics in infants treated for NEC Bell’s stage II and III. 

The standard duration of antibiotic therapy for NEC has reported to range from 7 to 21 days, and the antimicrobials used vary widely (Bull et al, 2021).   However, time to disease resolution has been found to differ by NEC severity and Bull et al (2021) therefore suggests that antibiotic course duration should vary dependant on the severity of NEC. 

The relationship of enteral nutrition and the development of necrotising enterocolitis in preterm infants has been well described but, in relation to infants CHD the evidence base remains scant.  Nevertheless, the adoption of enteral feeding guidelines and the use of human breast milk has been advocated in order to reduce risk of NEC in infants with CHD (Cognata et al 2019 and Castillo et al, 2010). 

There are however, no established guidelines for the optimal timing for the re-introduction of enteral feeds following NEC, but clinicians are cautious and prolonged fasting periods are common (Good, Sodhi and Hackam, 2014 and Arbra et al, 2018).  The clinical course of NEC in infants with CHD is different to that of ‘classical’ NEC in preterm infants (Oztas, Bilici and Okur, 2023) and due to compromised haemodynamics due to their CHD diagnosis or low cardiac output state (LCOS), leads to concern of impaired mesenteric perfusion and increased risk of bowel ischaemia, a cautious approach to enteral feeding seems warranted. 

Investigations

At the time of NEC concern enteral feeds should be stopped, maintenance fluids commenced and an abdominal x-ray obtained that will enable NEC severity staging to be ascertained and further management initiated as per Appendix 1. 

In addition the following should be obtained:

  • Blood cultures
  • U&Es, Ca, LFTs, FBC, Coag and CRP
  • PCT (procalcitonin)

Management of NEC in PICU

A NEC management pathway has been developed (Appendix 1) for use within PICU and has received approval from both the general surgical and cardiac faculty. 

Appendix 1: PICU NEC Management Pathway

PICU NEC management pathway

AXR findings are used to define NEC Category as signs and symptoms may be due to other pathology ie sepsis.

Access this appendix as a pdf here.

 

Editorial Information

Last reviewed: 06/01/2025

Next review date: 31/01/2028

Author(s): Isobel Macleod, Michael Jacovides, Mark Danton, Mark Davidson .

Version: 1

Approved By: Cardiac Faculty, PICU and General Surgeons

Document Id: 1186

References

Arbra, C.A., Oprisan, A., Wilson, D.A., and Ryan, R.M. and Lesher, A.P. (2018) Journal of Pediatric Surgery. 53 1187-1191.

Bell, M.J., Ternberg, J.L., Feigin, R.D., Keating, J.P., Marshal, R., Carton, L. and Brotherton, T. (1978) Neonatal Necrotising Enterocolitis Therapeutic Decisions based Upon Clinical Staging. Annals of Surgery. 187 (1) 1-7.

Brown, K.L., Ridout, D., Pagal, C., Wray, J., Anderson, D., Barron, D.J., Cassidy, J., Davis, PJ. Rodrigues, W., Stoica, S., Tibby, S., Utley, M. and Tsang, V.T. (2019) Incidence and risk factors for important early morbidities  associated with pediatric cardiac surgery in a UK population. The Journal of  Thoracic and Cardiovascular Surgery. 158 (4) 1185-1196.

Bull, K.E., Gainey, A.B., Cox, C.L., Burch, A.K., Durkin, M. and Daniels, R. (2021) Evaluation of Time to Resolution of Medical Nectrotizing Enterocolitis Using Severity-Guided management in a Neonatal Intensive Care Unit. Journal of Pediatric Pharmacology Therapy. 26 (2) 179-186.

Burge, K.Y., Gunasekaran, A., Makoni, m.M., Mir, A.M., Burkhart, H.M. and Chaaban, H. (2002) Clinical Characteristics and Potential pathogenesis of Cardiac Necrotizing Enterocolitis in Neonates with Congenital Heart Disease: A Narrative review. Journal of Clinical Medicine. 11 (3987) 

Castillo, S.L., McCulley, M.E., Khemani, R.G., Jeffries, H.E., Thomas, D.W., Peregrine, J., Wells, W.J., Starnes, V.A. and moromisato, D.Y. (2010) Reducing the Incidence of necrotizing Enterocolitis in Neonates with Hypoplastic Left Heart Syndrome with the Introduction of an Enteral Feeding protocol. Pediatric Critical Care Medicine. 11 92) 1-5.

Cognata, A., Kataria-Hale, J., Griffiths, P., Maskatia, S., Rios, D., O’Donnell, A., Roddy, D.J., Ehollin-Ray, A., Hagan, J., Placencia, J. and Hair, A.B. (2019) Human Milk Use in the Preoperative Period is Associated with a Lower Risk of Necrotising Enterocolitis in Neonates with Complex Congenital Heart Disease. The Journal of Pediatrics. 215 11-16. 

Deitch, A.M., Moynihan, K., Przybyski, R., Gauvreau, K., Braudis, N.J., Farr, B., Modi, B., Mills, K.I., Nathan, M. and Levy, P.Y. (2023) Risk Factors for Adverse Outcomes in Term Infants with CHD and Definitive Necrotising Enterocolitis. Cardiology in the Young. 25 1-9 

Gill, E.M., jung, K. and Ellebaek, M.B. (2022) Antibiotics in the Medical and Surgical Treatment of Necrotising Enterocolitis. A Systematic Review. BMC Pediatrics. 22 (66) 1-10 

Good, M. Sodhi, C.P. and Hackam, D.J. (2014) Evidence Based Feeding Strategies Before and After the Development of Necrotising Enterocolitis. Expert Review Clinical Immunology. 10 (7) 875-884.

Iannucci, G.J., Oster, M.E. and Mahle, W.T. (2013) Necrotising enterocolitis in Infants with Congenital Heart Disease: The Role of Enteral Feeds. Cardiology in the Young. 23 553-559.

Lau, P.E., Cruz, S.M., Ocampo., E.C., Nuthakki, S., Style, C.C., lee, T.C., Wesson, D.E. and Olutoye, O.O. (2018) Nectotising Enterocolitis in Patients with Congenital Heart Disease: A Single Center Experience. Journal of Pediatric Surgery. 53 914-917.

Oztas, T., Bilici, S. and Okur, M. (2023) Comparison of Cardiogenic NEC and Classical NEC in the Fouth Level Neonatal Intensive Care Center. Annals of Pediatric Surgery. 19 (16) 1-5

Pickard, S.S., Feinstein,J.A., Popat, R.A., Huang, L. and Dutta, S. (2009) Short and Long Term Outcomes of Necrotizing Enterocolitis in Infants with Congenital Heart Disease. Pediatrics. 123 (5) e901-e906.

Schuchardt, E.L., Kaufman, J., Lucas, B., Tierman, K., Lujan, S.O. and Barnett, C. (2013) Suspected Necrotising Enterocolitis after Surgery for CHD: An Opportunity to Improve Practice and Outcomes. Cardiology in the Young. 28 639-646.