Clinical meaning
The abdomen contains organs from multiple body systems, including the gastrointestinal tract (stomach, small and large intestines, liver, gallbladder, pancreas), the urinary system (kidneys, ureters, bladder), the spleen, and the abdominal aorta. The peritoneum is a serous membrane that lines the abdominal cavity and covers most abdominal organs; inflammation of this membrane (peritonitis) constitutes a surgical emergency. For clinical assessment, the abdomen is divided into four quadrants using the umbilicus as the central landmark: right upper quadrant (RUQ) containing the liver, gallbladder, and right kidney; left upper quadrant (LUQ) containing the spleen, stomach, and left kidney; right lower quadrant (RLQ) containing the appendix, cecum, and right ovary/fallopian tube in females; and left lower quadrant (LLQ) containing the sigmoid colon and left ovary/fallopian tube. Alternatively, nine regions may be used for more precise localization. Abdominal assessment follows a specific sequence that differs from other body system assessments: inspection, auscultation, percussion, and palpation. Auscultation must be performed BEFORE percussion and palpation because physical manipulation of the abdomen can alter peristaltic sounds and produce false findings. Normal bowel sounds occur every 5 to...