Abdominal Anatomy and Pain

Abdominal Anatomy

• Peritoneum: a membrane that lines the abdominal cavity (parietal peritoneum) and covers organs within it (visceral peritoneum)
• Retroperitoneal space: area posterior to the peritoneum, between the peritoneum and the back, containing organs like kidneys, pancreas, and aorta

Types of Abdominal Pain

• Visceral Pain: poorly localized, dull pain that arises from abdominal organs, difficult to detect due to fewer nerve endings
• Parietal Pain: localized, intense, sharp, and constant pain that arises from parietal peritoneum, worsens with movement
• Tearing Pain: sharp pain that feels like body tissues are being torn apart, often associated with AAA damage to aorta lining
• Referred Pain: pain felt in a location other than where the pain originates, common with gallbladder and spleen pain radiating to the shoulder

Abdominal Conditions

• Appendicitis: infection of the appendix, most common cause of surgery, symptoms include nausea and vomiting, pain in RLQ
• Peritonitis: inflammation of the peritoneum, caused by ruptured spleen/appendix, symptoms include rigid abdomen, pain, and fever
• Cholecystitis/Gallstones: inflammation of the gallbladder often caused by gallstones, symptoms include pain that may radiate to shoulder, RUQ
• Pancreatitis: inflammation of pancreas, common in chronic alcoholics, pain may radiate to the back or shoulders or epigastric
• GI Gastrointestinal Bleeding: bleeding from within the GI system, causes include blood without stool through the rectum or vomiting of frank blood, symptoms include no pain
• AAA (Abdominal Aortic Aneurysm): ballooning or weakening in the wall of the aorta, symptoms include pain radiating to the back, sharp, and tearing pain
• Hernia: hole in the muscle layers of abdominal wall, allowing tissue to protrude up against the skin, symptoms include onset of pain after lifting, mass or lump on the abdominal wall, very painful
• Renal Colic (Kidney Stones): small hard stones making way down the ureter, causing flank pain that often radiates to the groin area, patient can't find position of comfort, writhing
• Cardiac Involvement: myocardial infarction may be felt as abdominal discomfort
• Female Reproductive (Ectopic Pregnancy): fertilized embryo implants outside of the uterus, causing internal bleeding/abdominal pain

Physical Examination of the Abdomen

• Inspection: distension, bloating, discoloration, abnormal protrusions
• Palpation: done with fingertips
• Vital signs: important to reassess every 5 minutes