Primary vs Staged (Silo) Closure
Primary closure
- All viscera reduced & abdomen closed in one operation
- Only if the abdominal cavity can accommodate them without dangerous pressure
Staged (silo) closure
- A silo (Schuster / spring-loaded) is placed and the viscera are gradually reduced over days
- Chosen when primary closure would raise pressure too high; a ventral hernia can deliberately be left to prevent compartment syndrome
Criteria that force staged closure / decompression
Consider a silo or surgical decompression if any of: intragastric or intravesical pressure > 20 cmH₂O, peak inspiratory pressure > 35 cmH₂O, EtCO₂ > 50 mmHg, a rising CVP / airway pressure above baseline, lower-limb congestion or cyanosis, falling SpO₂, or failure of a saphenous-vein infusion to flow. Numbers decide
Abdominal Compartment Syndrome
Forcing viscera into too-small a cavity → ↑ intra-abdominal pressure
↑ Intra-abdominal pressure
Cardiovascular↓ venous return → ↓ cardiac output → hypotension; lower-body venous congestion
Respiratory↑ airway pressures, ↓ compliance, hypercarbia, hypoxia
Splanchnic / renalCongestion of organs, bowel ischaemia → necrosis/perforation/NEC, acidosis, oliguria/anuria, hepatic impairment & altered drug metabolism
Recognise it intra-op
Watch for a rising airway pressure, falling BP & SpO₂, lower-limb mottling/cyanosis and oliguria as the abdomen is closed. If they appear, ask the surgeon to abandon primary closure and place a silo — a tight abdomen kills bowel and kidneys.