1BISAP Score — Pancreatitis Severity Guide
The BISAP (Bedside Index of Severity in Acute Pancreatitis) score was developed by Wu et al. (2008) from a prospective study of 17,992 hospitalised pancreatitis patients in the United States. It was designed as a simple five-point bedside score calculable within 24 hours of admission — without requiring CT imaging or complex scoring algorithms — to predict in-hospital mortality from acute pancreatitis. It outperforms the Ranson score in terms of bedside applicability while achieving comparable discriminative accuracy.
| BISAP Score | In-Hospital Mortality | Organ Failure Risk | Severity Class |
|---|---|---|---|
| 0 | <1% | <2% | Mild |
| 1 | ~1% | ~5% | Mild |
| 2 | ~3% | ~10% | Moderate |
| 3 | ~10% | ~25% | Severe |
| 4 | ~20–30% | ~40% | Severe |
| 5 | ~50% | ~50%+ | Critical |
Revised Atlanta Classification (2012) — Severity Categories
- Mild AP: No organ failure, no local or systemic complications. Usually self-limited. 30% of cases. Mortality <1%. Treatment: supportive — aggressive early IV fluid resuscitation, analgesia, early oral feeding when tolerated
- Moderately Severe AP: Transient organ failure (<48h) and/or local complications (acute peripancreatic fluid collection, pancreatic necrosis) without persistent organ failure. HDU/step-down care. Mortality 8%
- Severe AP: Persistent organ failure (>48h) in one or more organ systems (respiratory, renal, cardiovascular). ICU admission required. Mortality 30–50%
Fluid Resuscitation in Acute Pancreatitis
Early aggressive IV fluid resuscitation within the first 24 hours is the cornerstone of AP management. The ACG 2013 and AGA 2024 guidelines recommend:
- Fluid choice: Lactated Ringer's solution (LR) preferred over normal saline — reduces SIRS incidence and improves outcomes (WATERFALL trial 2022, Chen et al.)
- Rate: 250–500 mL/hr for first 12–24 hours in non-cardiac patients. Goal-directed resuscitation targeting: urine output >0.5 mL/kg/hr, HR <100, MAP >65 mmHg, haematocrit 35–44%
- Reassess at 6 and 24 hours: Decrease rate if haematocrit falling, BUN falling, adequate urine output. Avoid over-resuscitation — associated with abdominal compartment syndrome
- Nutritional support: Oral or enteral nutrition as early as tolerated. Early enteral feeding (within 24 hours) via nasogastric or nasojejunal route preferred in severe AP — reduces infections and mortality vs parenteral nutrition
Common Causes of Acute Pancreatitis — Memory Aid "I GET SMASHED"
- Idiopathic (15–25%)
- Gallstones (40–50% — most common in South Asia and women)
- Ethanol/alcohol (30% — most common in Western countries)
- Trauma (blunt abdominal injury)
- Steroids, Mumps/infection, Autoimmune (IgG4 pancreatitis)
- Scorpion sting (relevant in India — Mesobuthus tamulus), Hypertriglyceridaemia (>1000 mg/dL), ERCP (post-ERCP pancreatitis ~3%), Drugs (azathioprine, didanosine, valproate)
2Frequently Asked Questions
The BISAP score provides a reliable bedside risk stratification within the first 24 hours of hospital admission for acute pancreatitis, guiding appropriate care level and early fluid resuscitation.
Related calculators on RxMedCalc
Medical disclaimer: This calculator is for educational and clinical decision-support purposes only. It does not replace clinical judgment or specialist consultation. RxMedCalc is not liable for clinical decisions made solely on this tool.