Overview
Gastroschisis
1. Clinical Overview
Summary
Gastroschisis is a congenital abdominal wall defect located to the RIGHT of the umbilicus, through which abdominal contents (usually bowel) herniate WITHOUT a covering membrane. The exposed bowel is damaged by amniotic fluid, leading to a characteristic inflammatory "peel".
Key Facts
| Aspect | Detail |
|---|---|
| Location | RIGHT of umbilicus (cord insertion normal) |
| Covering | NONE - bowel exposed |
| Associated anomalies | LOW (isolated defect) |
| Maternal age | Young mothers |
| Main concern | Heat/fluid loss, bowel damage, dysmotility |
Clinical Pearls
- "GAST-right-schisis": Mnemonic - Gastroschisis is to the RIGHT
- No sac = Gastroschisis: Exomphalos has a sac
- Young mothers: Associated with young maternal age, smoking, drugs
- Bowel peel: Inflammatory thickening from amniotic fluid exposure
2. Epidemiology
Incidence & Demographics
| Factor | Detail |
|---|---|
| Incidence | 1 in 2000-3000 live births |
| Trend | Increasing worldwide |
| Maternal age | Young mothers (<20 years) |
Risk Factors
| Risk Factor | Association |
|---|---|
| Young maternal age | Strong association |
| Smoking | Increased risk |
| Recreational drugs | Cannabis, cocaine |
| Low BMI | Underweight mothers |
| Vasoactive medications | Pseudoephedrine, aspirin |
3. Pathophysiology
Embryological Defect
Normal Development:
- Physiological herniation of gut into umbilical cord (weeks 6-10)
- Return to abdomen by week 12
Gastroschisis:
- Vascular disruption of right omphalomesenteric artery
- Ischaemic damage to abdominal wall (right of cord)
- Bowel herniates through defect
- NO peritoneal covering (unlike exomphalos)
Bowel Damage in Utero
| Feature | Mechanism |
|---|---|
| Inflammatory peel | Contact with amniotic fluid |
| Bowel thickening | Chemical peritonitis |
| Matted loops | Adhesions |
| Dysmotility | Myenteric plexus damage |
4. Clinical Presentation
Antenatal Detection
At Birth
| Finding | Description |
|---|---|
| Defect location | Right of umbilicus (typically 2-4 cm defect) |
| Herniated contents | Usually small bowel ± stomach, colon |
| Bowel appearance | Oedematous, matted, "peel" covering |
| Cord | Normal insertion |
Gastroschisis vs Exomphalos
| Feature | Gastroschisis | Exomphalos (Omphalocele) |
|---|---|---|
| Location | RIGHT of cord | INTO the cord (central) |
| Covering | NONE | Peritoneal SAC present |
| Cord insertion | Normal | Inserted into sac |
| Maternal age | Young | Older |
| Associated anomalies | LOW (5-10%) | HIGH (50-70%) |
| Chromosomal abnormalities | Rare | Common (trisomies) |
| Contents | Bowel | Bowel ± liver |
Diagnosed on anomaly scan (18-20 weeks)
Common presentation.
Free-floating bowel loops in amniotic fluid
Common presentation.
Normal cord insertion
Common presentation.
5. Clinical Examination
Immediate Assessment
| Component | Importance |
|---|---|
| Bowel viability | Colour, perfusion |
| Size of defect | Feasibility of primary closure |
| Other anomalies | Though rare |
| Fluid status | Risk of decompensation |
| Temperature | Risk of hypothermia |
6. Investigations
Antenatal
| Investigation | Purpose |
|---|---|
| Detailed USS | Confirm diagnosis, assess bowel |
| Amniocentesis | NOT routinely needed (low anomaly risk) |
| Serial growth scans | Monitor for FGR |
Postnatal
| Investigation | Purpose |
|---|---|
| Blood gas | Metabolic status |
| Electrolytes | Fluid/electrolyte balance |
| Blood glucose | Neonatal hypoglycaemia |
| FBC | Sepsis monitoring |
7. Management
Immediate Management (Delivery Room)
| Action | Purpose |
|---|---|
| Wrap bowel in cling film | Prevent heat/fluid loss |
| OR silo bag | Transparent, allows monitoring |
| NG tube (large bore) | Decompress stomach |
| IV access | Fluid resuscitation |
| IV fluids | 150-200 mL/kg/day initially |
| Lateral positioning | Prevent kinking of mesentery |
| Measure temperature | Maintain normothermia |
| Do NOT attempt to reduce | Wait for surgical team |
Surgical Management
| Approach | Indication |
|---|---|
| Primary closure | Small defect, minimal bowel oedema |
| Staged reduction (Silo) | Large defect, oedematous bowel |
Silo (Staged) Reduction
Preformed Silo Applied
↓
Bowel Gradually Reduced (over days)
↓
Serial Tightening of Silo
↓
Primary Closure When Bowel Accommodated
(typically 5-7 days)
Postoperative Care
| Aspect | Management |
|---|---|
| TPN | Essential - prolonged enteral feeding intolerance |
| Gradual feeding | Start when bowel function returns |
| Watch for NEC | Higher risk |
| Infection prevention | Strict asepsis |
8. Complications
| Complication | Notes |
|---|---|
| Sepsis | Open defect, central lines |
| Bowel ischaemia/necrosis | May need resection |
| Short bowel syndrome | If extensive resection |
| Necrotising enterocolitis | Higher risk |
| Prolonged ileus | Due to bowel dysmotility |
| TPN-related | Cholestasis, line sepsis |
| Intestinal atresia | Associated in 10-15% |
9. Prognosis & Outcomes
| Factor | Outcome |
|---|---|
| Overall survival | >90% |
| Uncomplicated | Excellent prognosis |
| Complicated (atresia, necrosis) | Increased morbidity |
| Feeding delay | Median 3-4 weeks to full feeds |
| Length of stay | 3-6 weeks typically |
Long-Term
- Most have normal quality of life
- May have GI dysmotility as children
- Adhesive small bowel obstruction risk
10. Evidence & Guidelines
| Organisation | Key Points |
|---|---|
| BAPM | Immediate management guidance |
| BAPS | Surgical principles |
| GEEPS | Parent support and information |
11. Patient / Layperson Explanation
What is gastroschisis? It is a condition where a baby is born with a hole in the tummy wall next to the belly button, through which the bowel (intestines) comes out. Unlike some similar conditions, there is no skin covering the bowel.
How does it happen? It happens during development in the womb. The exact cause is unknown, but it is NOT caused by anything the mother did or didn't do.
How is it treated?
- At birth, the bowel is kept moist and warm with special wraps
- Surgery is needed to put the bowel back inside and close the hole
- If the hole is small, this can be done in one operation
- If large, a special bag (silo) holds the bowel while it is gradually pushed back over several days
What is the outlook? Over 90% of babies do very well. Recovery takes weeks because the bowel needs time to start working normally. Most children grow up healthy with no long-term problems.
12. References
- Bradnock TJ, et al. Gastroschisis: BAPS-CASS National Study. Lancet. 2011.
- Holland AJ, et al. Gastroschisis: An Update. Pediatr Surg Int. 2010.
- GEEPS (Gastroschisis, Exomphalos, Exstrophy, Prune-belly Support). www.geeps.org.uk