Chapter 86: Peritoneum and Retroperitoneum Flashcards
What is the Cullens sign?
A characteristic ring of SQ haemorrhage around the umbilicus often seen with haemoperitoneum or peritonitis bu direct extension from the abdominal cavity to the SQ
What lines the pelvic and peritoneal cavities?
Transverse fascia and mesothelial cells (peritoneum)
What are omental milky spots?
A source of neutrophils, macrophages and lymphocytes, an important part of the peritoneal defense mechanism
How would you classify peritoneal fluid as normal, transudate, modified transudate and exudate based on cell count and protein concentration?
Transudate < 1500 cells/uL and <2.5 g/dL
Modified 1500-7k and 2.5-5 g/dL
Exudate >5k and >3 g/dL
What is the predominant cell type in normal peritoneal fluid?
Macrophage
What rate of fluid absorption is the peritoneal cavity capable of?
3-8% of bodyweight per hour
What is normal intraabdominal pressure in dogs?
2 - 7.5 cmH2O
What is required for adhesion formation?
Fibrinous exudate (from surgical manipulation or many diseases)
and vascular damage/ischemia
In the absence of ischemia, fibrin undergoes fibrinolysis. When accompanied by vascular damage, fibrin is infiltrated by fibroblasts which produce collagen and form firm adhesions
In addition to ischemia, what else (4) increases the likelihood of adhesion formation?
- Endotoxemia
- Intestinal manipulation
- Bowel distention
- Dessication of the serosal surfaces
What are (6) ways to reduce the likelihood of adhesion formation?
- Prevention of desiccation (moisten tissues regularly)
- Gentle tissue handling
- Meticulous hemostasis
- Precise suture placement
- Complete removal of blood clots and foreign debris
- Thorough lavage
What are the (5) methods the peritoneum uses for defense?
- Release of complement (C3a, C5a) which stimulates neutrophil chemotaxis and degranulation of basophils and mast cells
- Diaphragmatic lymphatics
- Resident leukocytes and macrophages
- Abscess formation
- Resident natural killer cells
What is the major proinflammatory mediator produced by mesothelial cells?
What stimulates its production?
IL-8
- Stimulated by TNFa and IL-1B from macrophages
What is the main anti-inflammatory mediator in septic peritionitis?
IL-10 - protects against lethal shock
SIRS is proportional to the degree of elevation of what proinflammatory cytokines?
IL-1B
TNFa
IL-6
What (5) substances are known adjuvants in septic peritonitis?
(Intraperitoneal substances which enhance bacterial growth)
- Gastric mucin polysaccharide
- Bile salts
- Haemoglobin
- Barium
- Peritoneal fluid volume