RT Book, Section A1 Brady, Matthew A1 Mahoney, Eric A2 Doherty, Gerard M. SR Print(0) ID 1105488250 T1 Peritoneal Cavity T2 CURRENT Diagnosis & Treatment: Surgery, 14e YR 2015 FD 2015 PB McGraw-Hill Education PP New York, NY SN 9780071792110 LK accessmedicine.mhmedical.com/content.aspx?aid=1105488250 RD 2024/10/06 AB The peritoneum is the thin serous membrane that lines the peritoneal cavity. It is the largest serous surface layer in the human body and its surface area is similar to the skin. The structure is made up of a single, flat, layer of mesothelial cells, rich in microvilli. Beneath the mesothelium are a basement membrane and a loose collagen network containing vascularized connective tissue with scattered fibroblasts and macrophages. Normally there is between 5 and 20 mL of free peritoneal fluid, this can vary in women, peaking after ovulation. Normal peritoneal fluid has a specific gravity less than 1.016, protein concentration less than 3g/dL, pH between 7.5 and 8, and a white blood cell count less than 3000/μL. The peritoneum is divided anatomically into parietal and visceral components. The parietal peritoneum underlies the anterior, later, and posterior abdominal walls as well as the undersurface of the diaphragm and pelvic basin. The visceral peritoneum is reflected over the viscera within the abdominal cavity.