What is the peritoneum? | Serous membrane lining the cavity of the abdomen and covering the abdominal organs
Surface 1.7 m²
Divides organs into:
Intraperitoneal organs:
-Liver, spleen, stomach, superior part of the duodenum, jejunum, ileum, transverse colon, sigmoid colon and superior part of the rectum.
Retroperitoneal organs :
-found posterior to the peritoneum in the retroperitoneal space with only their anterior wall covered by the parietal peritoneum. |
What is the main role of the peritoneum? | Policeman of abdomen
Protection of the abdominopelvic organs
Connect organs with each other
Maintain the position of organs by suspending them with ligaments
Prevent friction while organs move
Cicatrisation via TNF alfa, TGF beta, monoxydes d’azotes
Elimination of bacteria |
How is the division of peritoneum? | . |
What is the omentum? | Sheet of fatty tissue that stretches over the abdomen
Role in immune response and the growth of certain cancers
One of the human body's largest organs |
Image of lesser and greater omentum? | . |
What is the mesentery? | Folds of peritoneum that suspend organs from the posterior abdominal wall.
Carry neurovascular bundles through the fat between peritoneal layers to supply organs |
Image of mesentery? | . |
What are peritoneal ligaments? | . |
What is peritonitis? | A suppurative response of the peritoneal lining to direct bacterial contamination
Symptoms and signs:
- Fever and chills
-Tachycardia
-Acute abdomen
-Free air on plain films |
What are types of peritonitis? | Primary bacterial peritonitis:
- Hematogenous spread
- Transluminal invasion in patients with advanced liver disease and reduced ascitic fluid protein concentration
- Monobacterial :E.coli, Klebsiella, Strepto
Secondary bacterial peritonitis :
-Disruption of a hollow viscus
-Polymicrobial
-Bile, urine, blood, stools
Tuberculous peritonitis:
-Young women : 0.5 % of TB
-White spots on peritoneum
-Treatment : medical treatment , surgery if complication |
How is dx of peritonitis done? | Diagnosis:
Abdominal x-ray : free air and ileus pattern
Water-soluble contrast : location of perforated viscus
Abdominal pelvic CT scan with intravenous (IV) and oral contrast is best for finding source of bacterial peritonitis
Operation should not be delayed to obtain this test in patients with an acute abdomen |
What is DD of peritonitis? | Appendicitis
Perforated gastroduodenal ulcers
Diverticulitis
Gangrenous cholecystitis
Acute salpingitis
Nonvascular small bowel perforation
Mesenteric ischemia |
What are types of mesenteric ischemia? | . |
How is tx of peritonitis? | Resuscitation with IV fluids and electrolyte replacement
Operative control of abdominal sepsis
Systemic empiric antibiotics that cover aerobic and anaerobic enteric organisms; directed antibiotic therapy based on operative or aspiration cultures
Prognosis: mortality for generalized peritonitis is 40% |
What is endometriosis? | Deposits of endometrium outside of the uterus that respond to hormonal cycles
Prevalence in United States is 2% among fertile women and 3- to 4-fold greater in infertile women
Symptoms and signs:
-Dysmenorrhea
-Constant aching lower abdominal pain, beginning 2–7 days before the onset of menses and increasing in severity until menstrual flow subsides
-Infertility
-Dyspareunia
Ultrasound often shows complex fluid-filled masses that cannot be distinguished from neoplasms |
What is DD of endometriosis? | Pelvic inflammatory disease
Uterine myomas
Ovarian neoplasms, polycystic ovary disease
Acute appendicitis
Ectopic pregnancy, threatened abortion |
How is tx of endometriosis? | Goal is to ameliorate symptoms and preserve fertility
Mainstay of therapy is medical inhibition of ovulation
Laparoscopy or laparotomy to resect or ablate lesions, with or without suspension of the uterus for patients <35 years to preserve reproductive function (controversial)
Surgery is indicated for failure of medical management
Medications: gonadotropin-releasing hormone analogs
Prognosis for reproductive function in mild or moderate endometriosis is good with conservative management |
What are mesenteric and omental cysts? | Rare lesions
Result from sequestration of lymphatic tissue during development
Thin walls lined with endothelial cells without surrounding smooth muscle
Cysts may be filled with serous lymphatic fluid (common in the mesocolon and omentum) or chyle (common in small bowel mesentery) |
What are S&S of mesenteric and omental cysts? | -Bleeding
-Rupture
-Torsion
-Possible infection of the cyst
-Soft mobile abdominal mass
-Chronic abdominal pain
Ultrasound : thin-walled, hypoechoic, homogeneous mass uniloculated or multiloculated
CT scan : thin-walled fluid density mass that may be uniloculated or multiloculated |
What is DD of mesenteric and omental cysts? | Pancreatic pseudocysts
Enteric duplication
Echinococcal cysts
Retroperitoneal tumors
Tumor metastasis
Large ovarian cysts
Pseudomyxoma peritonei |
How is tx of mesenteric and omental cysts? | Simple excision of the cyst without resection of adjacent organs or major neurovascular structures
Partial excision with marsupialization is alternative when complete excision is not possible
Internal intestinal drainage is an option, particularly if cyst is adjacent to intestinal wall and may be an enteric duplication |
What are complications of mesenteric and omental cysts? | Volvulus of cyst with vascular compromise and infarction of the adjacent intestine
Bleeding into the cyst
Cyst rupture into the abdominal cavity
Cyst infection |
What are peritoneal neoplasms? | Secondary implants from intraperitoneal cancers (eg, ovarian, gastric, pancreatic)
Primary peritoneal tumors : mesodermal lining of the peritoneum
Malignant mesothelioma :History of asbestos exposure in
Pseudomyxoma peritonei :low-grade mucinous cystadenocarcinoma of the appendix or ovary |
What are S&S of peritoneal neoplasms? | Symptoms and signs:
-Weight loss
-Crampy abdominal pain
-Large abdominal mass
-Distention due to ascites
Percutaneous biopsy of accessible peritoneal thickening versus diagnostic laparoscopy with biopsy
CT scans pleural effusions, ascites, peritoneal and mesenteric thickening |
What is DD of peritoneal neoplasms? | Peritoneal mesotheliomas
Well-differentiated papillary mesotheliomas
Pseudomyxoma peritonei
Benign appendiceal mucocele
Adeno-carcinomatosis |
How is tx of peritoneal neoplasms? | Palliative cytoreductive surgery:
-Intraperitoneal chemotherapy, adjuvant intracavitary radiation
Cisplatin - or doxorubicin-based adjuvant chemotherapy for malignant mesothelioma, fluorouracil based adjuvant chemotherapy for pseudomyxoma peritonei |
How is prognosis of peritoneal neoplasms? | For malignant mesothelioma, long-term survivors (>1 year) have been reported with cytoreductive surgery combined with intraperitoneal chemotherapy
For pseudomyxoma peritonei, survival is 50% at 5 years and 30% at 10 years |
What are retroperitoneal abscesses? | Primary abscesses :hematogenous bacterial spread, most commonly of Staphylococcus aureus
Secondary abscesses :spread of infection from adjacent organs, mainly intestine
Symptoms and signs :
- Fever
-Flank, abdominal, back, thigh pain
-Leukocytosis
CT scan :differentiate between retroperitoneal hematomas and tumors; abscesses
Perform complete blood count; abdominal or pelvic CT scan with IV and oral contrast is essential |
What is DD of retroperitoneal abscesses? | Crohn disease
Ruptured appendicitis
Pancreatitis
Perforated diverticulitis
Posterior penetrating duodenal ulcer
Rule out intra-abdominal process with retroperitoneal extension |
How is tx of retroperitoneal abscesses? | Percutaneous drainage may be attempted in well-defined uniloculated abscesses
Percutaneous catheter drainage is less successful for retroperitoneal abscesses than for intra-abdominal abscesses
Most patients require open surgical debridement and drainage, ideally through an extraperitoneal flank approach, and systemic empiric antibiotics that cover aerobic and anaerobic enteric organisms |
How is prognosis of retroperitoneal abscesses? | Retroperitoneal abscesses :difficult to drain completely residual or recurrent abscess formation is common.
Mortality approaches 25% |
What is retroperitoneal fibrosis? | Extensive fibrotic encasement of the retroperitoneal tissues
Diffuse desmoplastic involvement of the retroperitoneum may cause obstructive jaundice or small or large bowel obstruction
Classic diagnostic triad :
Bilateral hydronephrosis/ hydroureter
Medial deviation of the ureters,
Extrinsic ureteral compression at the L4–L5 level
Ultrasound demonstrates hydronephrosis
CT scan or magnetic resonance imaging shows fibrotic process and the classic diagnostic triad |
What is DD of retroperitoneal fibrosis? | Retroperitoneal hematoma
Retroperitoneal abscess
Retroperitoneal sarcoma
Retroperitoneal teratoma
Rule out underlying malignancy, most commonly metastatic carcinoma or lymphoma |
How is tx of retroperitoneal fibrosis? | Perform urinary decompression with ureteral stents or percutaneous nephrostomy
Repair abdominal aortic aneurysm if present
Discontinue suspect medications
Initiate anti-inflammatory medications; prednisone and other immunosuppressants have been used with varying success
Prognosis: Gradual resolution is likely if no underlying cancer |
What is retroperitoneal hemorrhage? | History of trauma
Critically ill patients taking anticoagulation or antiplatelet medications
Patients with femoral vascular access, a common cause of clinically silent, large retroperitoneal hematoma
Symptoms and signs :
depend on location of retroperitoneal hemorrhage
include femoral nerve palsy
Flank and groin ecchymosis late sign of retroperitoneal hemorrhage
Cardinal laboratory finding is a falling hematocrit
Perform serial hematocrit evaluations and assess coagulation
CT scan differentiates among hematoma, tumor, and abscess |
What are traumatic retroperitoneal hematomas? | Zone 1 centrally located, associated with pancreaticoduodenal injuries or major abdominal vascular injury
Zone 2 in the flank or perinephric region, associated with injuries to the genitourinary system or colon
Zone 3 in the pelvis, associated with pelvic fractures or ileal-femoral vascular injury |
What is DD of retroperitoneal hemorrhage? | Retroperitoneal tumor
Retroperitoneal abscess
Intraperitoneal process with retroperitoneal extension
Rule out associated vascular or adjacent organ injury : Arteriography
. |
How is tx of retroperitoneal hemorrhage? | Obtain large-bore IV access
Type and cross 6 U packed red blood cells
Normalize coagulation factors
Patients with spontaneous retroperitoneal hemorrhage and blunt zone-3 injuries with falling hematocrit should have angiogram with focal embolization
Surgery :
- All zone-1 injuries
- Penetrating zone-2 injuries
- Blunt zone-2 injuries with expanding hematoma
- Penetrating zone-3 injuries, and evidence of femoral nerve palsy |
How is prognosis of retroperitoneal hemorrhage? | Depends on location and severity of injury |