Abdominal Pain

• Why is WBC not
• Important Epidemiology
  • Elderly
    • Age as risk factor for many concerning pathologies (AAA, mesenteric ischemia, diverticulitis, cancer, etc.)
    • Poor/diminished autonomic innervation/polyneuropathy may hide otherwise painful pathology
  • Immunocompromise
    • Misleading presentation d/t lack of inflammatory response
  • Women of Childbearing Age
    • Pregnant (ectopic!) until proven otherwise

Pain

- Visceral pain
	- from viscera (organs) sensing distention, inflammation, etc.
	- bilaterally innervated -> non-specific, diffuse pain initially
	- Perceived pain corresponds with embryonic somatic segments
		- Upper ABD Pain (Foregut) = stomach, liver/gallbladder, pancreas, duodenum
		- Periumbilical ABD Pain (Midgut) = Small bowel, proximal colon, appendix
		- Lower ABD Pain (Hindgut) = distal colon, male/female reproductive organs
- Somatic pain
	-  localized pain only occurs once the parietal peritoneum is involved
- Referred pain
	- Mixed fibers in spinal cord get misinterpreted and throws everything off

8 Causes of life threatening ABD Pain

1. Ruptured Ectopic
   • 1/100 pregnancies
   • Risks: IUD, infertility treatment, Hx of ectopic, non-white,
   • Sx: shock w/wo vag bleeding
   • Emergent Ultrasound
2. Ruptured AAA
   • Risks: Older, male, smoking (young w/ connective tissue disease)
   • Acute onset ABD pain w/ syncope/shock
3. Mesenteric Ischemia
   • Arterial (embolic/ischemic)
   • Venous (hypercoagulable)
   • Lactate (serial)
4. Intestinal Obstruction
5. Perforated Viscus
6. Acute Pancreatitis
7. Ascending Cholangitis
8. Complicated Diverticulitis/Appendicitis leading to rupture/abscess