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?
Transversalis 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 basd on cell count and protein concentration?
What is the predominant cell type in normal peritoneal fluid?
Macrophage
What rate of fluid absorption is the peritoneal cavity capable of?
3-8% BW 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/ischaemia
In the absense of ischaemia, fibrin undergoes fibrinolysis. When accompanied by vascular damage, fibrin is infiltrated by fibroblasts while produce collagen and form firm adhesions
In addition to ischaemia, what else increases the liklihood of adhesion formation?
- Endotoxaemia
- Intestinal manipulation
- Bowel distention
- Dessication of serosal surfaces
List some methods of reducing the liklihood of adhesion formation
- Prevention of dessication
- Gentle tissue handling
- Meticulous haemostasis
- Precise suture placement
- Complete removal of blood clots anf foreign debris
- Thorough lavage
List some methods of peritoneal defense
- Release of complement (C3a, C5a) which stimulates neutrophil chemotaxis and degranulation of basophils and mast cells
- Diaphragmatic lymphatics
- Resident leucocytes 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
SIRS is proportional to the degree of elevation of what proinflammatory cytokines?
- IL-1B
- TNFa
- IL-6
What substances are know adjuvants in septic peritonitis??
(Intraperitoneal substances which enhance bacterial growth)
- Gastric mucin polysaccharide
- Bile salts
- Haemoglobin
- Barium
- Peritoneal fluid volume
What are some broad functions of the omentum?
- Isolate and seal
- Absorbs bacteria and other particulate matter
- Rich blood supply
- Pronounced angiogenic activity
What is the cause of ileus secondary to septic peritonitis?
- Sympathoadrenergic reflex inhibition which completely blocks myenteric cholinergic neurons
What are the broad classifications of peritonitis?
- Primary or secondary
- Acute or chronic
- Localised or generalised
- Septic or aseptic
List some causes of aseptic and septic secondary peritonitis
What is sclerosing encapsulating peritonitis?
What is the recommened treatment?
A chronic form of peritonitis in which abdominal organs become encased in thick cocoon-like layers of collagenous connective tissue
Surgical exploration and biopsy and corticosteroids
List risk factors for post-op dehiscense and septic peritonitis
- Pre-op septic peritonitis
- Hypoalbuminaemia
- Hypoproteinaemia
- Intraop hypotension
What is highly correlated with survival in bile periotonitis
Presense of bacteria
What is early and late mortality in septic peritonitis most associated with?
- Early mortality - Gram negative aerobic organisms associated with high circulating concentrations of endotoxin, particularly E.Coli
- Late mortality: Presense of anaerobic organisms
What are the two most common bacteria isolated with bowel perforation?
- E.Coli
- Bacteroides fragilis
