Peritonitis Flashcards
What is the composition of the peritoneum?
thick mesothelium layer
on top of fibroelastic tissue
What are the divisions of the peritoneum?
- visceral peritoneum -> surrounding organs
- parietal peritoneum -> lining other surfaces of the cavity
what is the physiology of the peritoneum?
- few mls of peritoneum fluid -> pale yellow, viscid, & contains lymphocytes
- lubricates viscera -> allows easy movement & peristalsis
- irritation of parietal peritoneum -> severe localized pain (rich supply of nerves)
- irritation of visceral peritoneum -> poorly localized midline pain (poor supply of nerves)
Where does the visceral peritoneum get its innervation from?
slow C fibers running with sympathetic nerves transmit sensations
- dull crampy, poorly localized pain -> caused by ischemia, stretching, compression, traction, or chemical irritation
Where does the parietal peritoneum receive its innervation from?
A-fibers of somatic sensory nerves -> T7 - L1 anteriorly & L2 - L5 posteriorly
- sharp, well localized pain caused by irritation of parietal peritoneum
What is the function of the peritoneum?
- absorb large volume of fluids -> peritoneal dialysis in renal failure
- produce large volume of fluids -> ascites or inflammatory exudate (peritonitis)
- healing by development of new mesothelial cells
- visceral lubrication
- pain perception
- inflammatory immune responses
- fibrinolytic activity
- fluid absorption via diaphragmatic lymphatic during expiration -> abscess distant from primary disease
What is the difference between peritonitis & peritonism?
PERITONITIS
- inflammation of peritoneum (generalized or localized)
PERITONISM
- specific abdominal examination features
- irritation of peritoneum -> tenderness with guarding, rebound tenderness
What are the causes of peritoneal inflammation?
- bacterial -> GI & non-GI
- chemical -> bile & barium studies
- allergic -> starch peritonitis
- traumatic -> operative handling
- ischaemia -> strangulated bowel & vascular occlusion
- miscellaneous -> familial mediterranean fever
- primary spontaneous peritonitis -> pure streptococcal, pneumococcal, or haemophilus infection
What are the causes of acute bacterial peritonitis?
- invasion of peritoneal cavity by bacteria
- free fluid spillage -> circulation depends on attachments & gravity
What are the causes of non-bacterial peritonitis?
- acute pancreatitis
- intraperitoneal rupture of bladder
- hemoperitoneum
peritoneum will become infected by transmural spread of organisms from bowel -> systemic inflammatory response -> in a couple of hours -> bacterial peritonitis
(duodenal & gastric perforations are sterile for a couple of hours before becoming infected)
What are the routes to peritoneal infection?
- GI perforation -> perforated ulcer, appendix, diverticulum
- transmural translocation -> pancreatitis, ischemic bowel
- exogenous contamination -> drains, open surgery, trauma
- female genital tract -> pelvic inflammatory disease
- hematogenous -> septicemia (rare)
What is the cause of increased bacterial colonization in proximal bowel?
stasis & overgrowth caused by -> obstruction, chronic & acute motility disturbances
How does the biliary & pancreatic tract get infected?
gallstones
What are the organisms implicated in peritoneal infection?
2 or more bacterial strains
GRAM-NEGATIVE BACTERIA
- endotoxins -> causing release of TNF from leukocytes
- systemic absorption of endotoxin -> shock with hypotension & impaired tissue perfusion
CLOSTRIDIUM WELCHII
- exotoxins
BACTEROIDES
- gram-negative
- non-sporing
- predominant in lower intestine but escape detection because they’re anaerobic & grow slowly
- resistant to penicillin & streptomycin
- sensitive to metronidazole, clindamycin, lincomycin, & cephalosporin
What are the non-GI causes of peritonitis?
PELVIC INFECTIONS
- via the fallopian tubes
- due to chlamydia & gonococcus -> thinning of cervical mucus -> allow bacteria rom vagina into uterus & oviducts -> infection & inflammation
PERIHEPATITIS
- causes scar tissue to form on Glisson’s capsule (thin layer surrounding liver) -> Fits-Hugh-Curtis syndrome
FUNGAL PERITONITIS
- complicates severely ill patients
Summary of organisms in peritonitis?
GI source
- E. coli
- Streptococci
- Bacteroides
- Clostridium
- Klebsiella pneumoniae
Others
- staphylococcus
- streptococcis pneumoniae
- mycobacterium TB
- chlamydia trachomatis
- Neisseria gonorrhoea
- hemolytic strep
- fungal
What are the anatomical factors that cause localized peritonitis?
division of the greater sac of the peritoneum into
- subphrenic spaces
- the pelvis
- peritoneal cavity proper
peritoneal cavity proper is divided by transverse colon & mesocolon into
- supra colic compartment
- infra colic compartment
What are the anatomical factors that cause localized peritonitis?
division of the greater sac of the peritoneum into
- subphrenic spaces
- the pelvis
- peritoneal cavity proper
peritoneal cavity proper is divided by transverse colon & mesocolon into
- supra colic compartment
- infra colic compartment
when supracolic overflows (in case of peptic ulcer perforation) -> over colon -> infracolic or right paracolic gutter -> right iliac fossa
-> pelvis
What are the pathological factors leading to localized peritonitis?
- adhesions around affected organ
- retarded peristalsis
- greater omentum forms a barrier to prevent infection distribution
What are the factors that favour the development of diffuse peritonitis?
- speed of peritoneal contamination (prime factor)
- stimulation of peristalsis -> by eating or enema
- virulence of infecting organism
- young children -> small omentum
- disruption of localized collections -> by appendix mass or pericolic abscess injudicious handling
- immune deficiency -> steroid use, AIDS, old age
What are the initial symptoms of localized peritonitis?
signs of underlying condition (visceral inflammation)
- abdominal pain
- specific GI symptoms
- malaise
- anorexia
- nausea
WHEN PERITONEUM GETS INFLAMED -> abdominal pain worsens, temperature pulse rate increase
What are the pathognomonic signs of peritonitis?
- localized guarding
- rebound tenderness
- rigidity
What are the clinical features of localized peritonitis?
- inflammation under diaphragm -> shoulder tip (phrenic pain) -> C5 dermatome referred pain
- inflamed appendix in pelvic position OR salpangitis -> pelvic peritonitis -> rectal or vaginal examination reveals tenderness
What are the EARLY signs of generalized (diffuse) peritonitis?
- severe abdominal pain -> made worse by moving or breathing
- starts initially at site of lesion then spreads outward
- patient lies still
- tenderness & generalized guarding
- infrequent bowel sounds heard for a few hours -> stop with onset of paralytic ileus
- pulse & temperature rise according to degree of inflammation
what are the LATE features of generalized peritonitis?
- generalized rigidity
- distention
- absent bowel sounds
- circulatory failure -> cold, clammy extremities, sunken eyes, dry tongue, thready pulse, drawn anxious face (Hippocratic facies)
- unconsciousness
What are the diagnostic aids that should be preformed?
BEDSIDE
- urine dipstick -> urinary tract infection
- ECG
BLOOD
- baseline U&E for treatment
- full WBC count
- serum amylase -> diagnosis of acute pancreatitis (also in perforated duodenal ulcer, mesenteric ischemia)
What imaging modalities are used to diagnose peritonitis?
- Erect chest x-ray -> free sub diaphragmatic gas
- Supine abdominal -ray -> presence of dilated gas-filled loops of bowel (paralytic ileus)
- ultrasound
- CT
if patient is too ill for erect film -> lateral decubitus film shows gas beneath abdominal wall
When is the use of ultrasound of value?
- pelvis peritonitis in females
- localized right upper quadrant peritonism
What does CT demonstrate?
- the cause of peritonitis
- influences management decisions
How should a patient with peritonitis be managed?
GENERAL CARE
- care of critically ill
- nutritional support
- anesthesia & pain relief
PRINCIPLES OF SURGERY
- correction of fluid loss & circulating volume
- urinary catheterization +- GI decompression (NGT allows drainage till ileus resolves)
ANTIBIOTIC THERAPY
- parenteral broad-spectrum antibiotics
What is the importance of analgesia?
- pain relief is mandatory pre & post op (epidural) -> ALLOWS early mobilization & adequate physiotherapy post op
- helps prevent -> basal pulmonary collapse, DVT, & pulmonary embolism
taken in nursing position (sitting up)
when is early surgical intervention preferred over conservative?
- if patient is fit for anesthesia
- satisfactory resuscitation & return to normal physiology
MORE CAUTION IN PATIENTS WITH
- comorbidity
- old
When is non-operative treatment preferred?
in pancreatitis or salpingitis
primary peritonitis of streptococcal or pneumococcal origin
IF DIAGNOSIS IS MADE WITH CONFIDENCE
What is the approach in surgery in case of peritonitis?
- removing the cause & adequate peritoneal lavage +- drainage
- exploration + suction + mop drying
- saline lavage -> 3L containing antiseptic or antibiotic
What is the specific surgical approach in case of peritonitis caused by a perforated duodenal ulcer?
- exploratory laparotomy
- Graham’s patch
- thorough lavage
What is the specific surgical approach in case of peritonitis caused by a perforated appendix?
- exploration
- base of appendix & stump closure
- wash thoroughly
- close abdomen but leave skin open
What is the specific surgical approach in case of peritonitis caused by an intestinal perforation?
- exploratory laparotomy
- identify the viability status of the gut
- resection anastomosis/primary repair
- thorough lavage
What affects the prognosis & risk of complication in peritonitis?
- degree & duration of peritoneal contamination
- age & fitness of patient
- nature of underlying cause
What are the causes of biliary peritonitis?
- perforated cholecystitis
- postcholecystectomy -> cystic stump leakage
- > leakage from accessory duct in gallbladder bed
- > bile duct injury
- > T-tube drainage dislodgement - following other operations -> leaking duodenal stump postgastrectomy
- > leaking biliary-enteric anastomosis
- > leakage around percutaneous placed biliary drains - following liver trauma
What is the clinical presentation of biliary peritonitis?
- secondary to biliary tract damage
- patient has proven acute cholecystitis
- diffuse peritonitis
- jaundice occurs after a few hours
How should biliary peritonitis be managed?
laparoscopic -> evacuation of bile & peritoneal lavage
-> treat source of bile leakage (infected bile is more lethal)
-> exclude or relieve obstruction to a major bile duct
if duodenal stump is blown -> drain
-> cover by jejunal patch
How should a bile leak be managed after cholecystectomy or liver trauma?
- percutaneous ultrasound guided drainage
- endoscopic biliary stenting to reduce bile duct pressure
- drain removal when dry
- stent removal at 4-6 weeks
What are the clinical features of primary peritonitis?
- sudden onset of pain localized to lower half of abdomen
- temperature raised to 39C
- frequent vomiting
- severe profuse diarrhea after 24-48 hours (CHARACTERISTIC)
- increased micturition frequency
- diffuse peritonism
Who does primary peritonitis mostly affect?
- healthy girls -> vagina & fallopian tubes
- in males -> blood-borne & secondary to respiratory tract or middle ear infection
- in children -> may complicate nephrotic syndrome or cirrhosis
What are the investigations that should be performed & the treatment of primary peritonitis?
- leukocytosis > 30 000uL with 90% polymorphs
- start antibiotic therapy & correct dehydration & electrolyte imbalances -> THEN early surgery
- if spontaneous infection of pre-existing ascites -> peritoneal tap is diagnostic
