Laboratory Investigation
| INVESTIGATION | INDICATION |
| HB | If bleeding suspected |
| WCC | If infection suspected |
| EUC | if GI loss is prominent (e.g. vomiting and diarrhoea) or third spacing (e.g. bowel obstruction) If renal pathology suspected |
| LFT | If hepato-biliary disease is suspected |
| Amylase / Lipase | Biliary colic Pancreatitis |
| CK/Phosphate/Lactate | If an ischaemic process is suspected e.g. mesenteric ischaemia, closed loop obstruction |
| Calcium/Urate | Renal colic Pancreatitis (Ca++ for Ranson’s prognostic criteria) |
| ABG | If the patient is systemically unwell or an ischaemic process is considered |
IMAGING
An unwell patient may be too unstable for formal imaging. Early involvement of a surgeon (for immediate laparotomy) or ICU (for stabilisation) may be a better option.
IMAGING MODALITY |
INDICATION |
| CXR | Perforated viscus Pancreatitis (Ranson’s criteria) |
| AXR | Bowel obstruction (70% sensitivity) Renal calculi (90% sensitivity) |
| Upper abdominal Ultrasound | Biliary Colic Cholecystitis Obstructive Jaundice |
| Pelvic Ultrasound | Ectopic pregnancy Ovarian torsion Ovarian cyst rupture |
| CT abdomen | AAA (if stable) Renal calculi Intrabdominal collection/abscess |