Abdominal Surgery- Intestine Part A Flashcards
Causes of Anastomosis insufficiency
- Emergent surgery or prolonged operative time
- Decreased perfusion of the anastomosed bowel segments
- Increased pressure within the anastomosis (anastamosis bowel end not mobile enough)
Anastomosis Insufficiency Clinical Features
- Postoperative fever, tachycardia (usually 5–7 days following surgery)
- Abdominal distention, pain, and peritoneal signs
- Tender incision wound, purulent (or feculent) drainage
Anastomosis Insufficiency
Complications/ Tx
Complications:
- abscess formation,
- peritonitis,
- SIRS, sepsis
Treatment
- Revision surgery
- Treating complications (e.g., by giving broad-spectrum antibiotics in the case of infection)
- Endoluminal vacuum-assisted closure therapy
Wound Dehiscence
spontaneous wound rupture along an incision with fascial dehiscence and possible prolapse of underlying structures/organs; seen particularly often following laparotomy in abdominal surgery.
- Partial wound dehiscence; insufficiency of deep sutures while the superficial sutures remain intact
- Complete wound dehiscence: insufficiency of all suture layers
Wound Dehiscence
Causes
- Postoperative inflammatory processes in the abdomen
- Wound healing disorders
- Insufficient surgical sutures or poor suturing technique
- coughing or gas
- Premature mobilization of the patient
Wound Dehiscence
TX
Preoperatively
- Use of adhesive tapes as adjunctive wound support and abdominal binders to prevent further wound dehiscence.
- Mobilization of the patient with great care to avoid an increase in pressure
Urgent revision surgery (multiple irrigations and debridement of the wound margins) to prevent evisceration or a hernia later on
Meckel Diverticulum
- the most common congenital anomaly of the gastrointestinal tract and is caused by an incomplete obliteration of the omphalomesenteric duct.
- mucosal lining of the diverticulum may be either native ileal mucosa or heterotopic mucosa (most commonly gastric)
Meckel’s Diverticulum Epidemiology
- Prevalence: most common congenital gastrointestinal tract anomaly
- Sex:♂ > ♀
- Age:< 2 years of age
Meckel’s Diverticulum Pathophysh
- The omphalomesenteric (vitelline or vitellointestinal) duct is a patent tubular structure connecting the yolk sacto the alimentary tract in the embryo.
- The duct is normally obliterated by the 6th week of intrauterine life.
- Incomplete obliteration of the omphalomesenteric duct → persistence of the proximal (intestinal) segment of the duct → Meckel diverticulum
Meckel’s Diverticulum Anatomy
- Meckel diverticulum is a true diverticulum.
- Located ∼ 2 feet proximal to the ileocecal valve
- Usually ≤ 2 inches in size
- There may be 2 types of mucosal lining:
- Native ileal mucosa
- Heterotopic mucosa
- Blood supply: vitelline artery
Rule of 2s for Meckel’s
- 2% of the population,
- 2% are symptomatic,
- mostly in children < 2 years
- 2:1 males:females
- located 2 feet proximal to the ileocecal valv,
- ≤ 2 inches long,
- 2 types of mucosal lining
Meckel’s Diverticulum Clinical Features
- Asymptomatic
- Symptomatic (2–4%)
- Painless lower gastrointestinal bleeding (most common presentation)
- Currant jelly stools
- Tarry stools
- Hematochezia
- Painless lower gastrointestinal bleeding (most common presentation)
Meckel’s Diverticulum Diagnosis
- The initial work-up follows the same protocol as that for lower gastrointestinal bleeding and/or acute abdomen.
- Imaging
- Meckel scintigraphy scan (Meckel scan): a noninvasive nuclear medicine imaging technique using radiolabelled technetium (99mTc), which is preferentially absorbed by the gastric mucosa and can identify ectopic gastric mucosa
Meckel’s Diverticulum with risks for comlications
A Meckel diverticulum that is > 2 cm long, has a broad base (> 2 cm wide), has a palpable abnormality, or a fibrous band attaching it to the umbilicus
Meckels Diverticulum Tx
Asymptomatic
- Incidentally detected on laparotomy/laparoscopy
- Children or young adults: surgical resection always
- Adults <50: if high risk
- adults >50: Never (symptomatic rare)
Symptomatic or complicated
- Surgical resection
Meckel’s Diverticulum Complications
- Hemorrhage
- Bowel obstruction (usually affects terminal ileum) due to
- Intussusception
- Volvulus
- Bowel perforation
Uncomplicated Appendicitis
no evidence of an appendiceal fecalith, an appendiceal tumor, or complications, such as perforation, gangrene, abscess, or mass
1.
Complicated Appendicitis
associated with perforation, gangrene, abscess, an inflammatory mass, an appendiceal fecalith, or an appendiceal tumor
Acute Appendicitis
acute inflammation of the vermiform appendix typically due to an obstruction of the appendiceal lumen.
appendiceal fecalith
concretion of feces that develops in the appendix. Can obstruct the appendiceal lumen, which increases the risk of developing acute appendicitis (especially perforated appendicitis).
Appendicitis Epidemiology
Peak incidence: 10–19 years of age [3]
Sex: ♂ > ♀
Appendicitis Etiology
obstruction of the appendiceal lumen
- Lymphoid tissue hyperplasia; most common children and young adults
- Fecalith; most common adult
- Neoplasm; patients > 50 years of age
Physical Exam Findings of appendicitis
McBurney point tenderness
RLQ guarding and/or rigidity
Rebound tenderness
Rovsing sign
Psoas sign
Obturator sign
Clinical Features of appendicitis
Migrating abdominal pain:
- Initial diffuse periumbilical pain
- Localizes to the RLQ within ∼ 12–24 hours
Associated nonspecific symptoms
- Nausea
- Anorexia
- Vomiting
- Low-grade fever
- Diarrhea
Alvarado Score for Appendicitis
MANTRELS
- Migration of pain to RLQ = 1
- Anorexia = 1
- Nausea and/or vomiting = 1
- Tenderness in RLQ = 2
- Rebound pain = 1
- Elevated temperature > 37.3°C (99.1°F) = 1
- Leukocytosis (> 10,000/mm3) = 2
- Shift to the left (≥ 75% neutrophils) = 1
Likelihood of appendicitis
- ≤ 4: Low
- 5–6: Moderate
- ≥ 7: High
Pediatrics Appendicitis Score
- Migration of pain to RLQ = 1
- Anorexia = 1
- Nausea/vomiting = 1
- RLQ tenderness = 2
- RLQ pain elicited on coughing/jumping/percussion = 2
- Temperature ≥ 38°C (100.4°F) = 1
- Leukocytosis (≥ 10,000/mm3) = 1
- PMN ≥ 75% = 1
Likelihood of appendicitis
- ≤ 3: Low
- 4–6: Moderate
- ≥ 7: High
Appendicitis Imaging
CT abdomen with IV contrast
- preferred initial imaging modality in adults
- Supportive findings
- Distended appendix (diameter > 6 mm)
- Edematous appendix with periappendiceal fat stranding
Abdominal ultrasound
- Preferred initial imaging modality in children or pregnant patients
- Supportive findings
- Distended appendix (diameter > 6 mm)
- Target sign
MRI without Contrast
- Pregnant Patients
Abx Treatment of Uncomplicated Appendicitis
- Required coverage: against gram-negative and anaerobic organisms
- Combination therapy with a first-generationcephalosporin (e.g., cefazolin ) PLUS metronidazole
Operative Management with Appendectomy
- Indications:
- Emergency appendectomy is the current standard of care for acute appendicitis (without periappendiceal mass or abscess).
- Contraindications
- Appendiceal mass
- Appendicular abscess
Indications for NONOP Managment of appendicitis:
Periappendiceal abscess > 4 cm: image-guided percutaneous drainage
- Inflammatory appendiceal mass
- Appendiceal abscess
- Patient refusal of surgery
- High surgical risk due to comorbidities
- History of previous surgical/anesthesia complications
Appediceal Abscess
Description:
- pus and necrotic tissue around an inflamed appendix follows an untreated perforated appendix
Clinical features:
- manifests as a tender mass in the RLQ in an acutely ill patient
Treatment
- Abscess < 4 cm: antibiotic therapy alone is usually sufficient.
- Abscess > 4 cm: image-guided percutaneous drainage
Gangrenous appendicitis
Description:
- irreversible necrosis of the appendiceal wall
Clinical features
- High-grade fever, tachycardia, severe RLQ pain and tenderness
Treatment:
- emergency appendectomy (mottled purple apendix)
- IV antibiotics
Pylephlebitis
Description: septic thrombosis of the portal vein
Etiology: due to perforated appendicitis, diverticulitis, or necrotizing pancreatitis
Clinical features: fever
Appendicitis in pregnancy
- Atypical (higher) pain localization
- Perforated appendix is associated with a higher risk of fetal loss.
- Ultrasound is the diagnostic procedure of choice.
Chron’s Disease Epidemiology
Typical age of onset: bimodal distribution with one peak at 15–35 years and another one at 55–70 years
- Populations with higher prevalence
- Individuals of Northern European descent
- Individuals of Ashkenazi Jewish descent
Chrons Risk Factors
- Active and passive smoking of tobacco
- Familial aggregation
- Genetic predisposition
- (e.g., mutation of the NOD2 gene, HLA-B27 association)
Chrons Constitutional Symptoms
- Low-grade fever
- Weight loss
- Fatigue
Chrons Intestinal Symptoms
- Chronic diarrhea, typically nonbloody
- Abdominal pain, typically in the RLQ
- Malabsorption
- Palpable abdominal mass
- Enterocutaneous perianal fistulas, often associated with abscess formation
- Oral aphthae
Chrons Extraintestinal Symptoms
- Joints:
- enteropathic arthritis (e.g., sacroiliitis, spondylitis, inflammation of peripheral joints)
- Eyes
- Uveitis
- Iritis
- Episcleritis
- Skin
- Erythema nodosum
- Pyoderma gangrenosum
- Pyostomatitis vegetans
Pyoderma gangrenosum
- Associated with various conditions (e.g., IBD, rheumatoid arthritis, and trauma)
- very painful, rapidly-progressive, red spots that can change into purulent pustules or deep ulcerated lesions with central necrosis
- located at extensor side of the lower limbs
- Treated with immunosuppressants
Approach to Chrons Diagnosis
- Symptoms suggestive of CD, conduct blood tests and stool tests
- Confirm diagnosis with endoscopy and/or radiographic imaging and/or biopsy.
- Perform contrast radiological studies and/or ultrasonography to assess extent, severity, and complications
Labs for Chrons
Blood work
- CBC may show signs of pernicious anemia
- ↑ Inflammatory markers (↑ CRP, ↑ ESR, ↑ thrombocytes, and ↑ leukocytes)
Serology:
- ↑ Anti-Saccharomyces cerevisiae antibodies (ASCA)
- pANCA most likely negative
Stool analysis
- Rule out bacterial gastroenteritis
- Microscopy to examine presence of worm larvae or eggs (ova and parasites)
- Identification of bacterial toxins
Imaging for Chrons
-
Upper GI series with barium swallow and small bowel follow-through
- String sign
- Creeping fat
- Ultrasound findings
- Gastrointestinal wall thickening
- abscesses/fistulas
- MR enterography
- Characteristic findings are an edematous thickening of the intestinal wall
String Sign
contrast-filled bowel segment that resembles a string on x-ray
Snail Trails
physical examination finding characterized by longitudinal ulcerations in the oral mucosa.
Creeping Fat
pathognomonic hyperplasia of adipose tissue that results in accumulation of mesenteric fat around the circumference of the intestine
Endoscopy of Chrons
- Endoscopy confirms the diagnosis and may also be used as a therapeutic tool (e.g., dilatation of ducts, intestinal loops).
- Cobblestone sign: inflamed sections followed by deep ulcerations that resemble cobblestones
- Erythema and transmural inflammation
Chrons Pathology
- Skip lesions: a pattern of patchy, discontinuous inflammation in the bowel (affected areas interspersed with normal tissue)
- Creeping fat
-
Transmural inflammation
- Noncaseating granulomas
- Distinct lymphoid aggregates of the lamina propria
Approach to Chrons Tx
- Treating acute disease
- Inducing clinical remission
- Maintaining response/remission
- Patients should be stratified according to their specific prognostic risk factors.
- individually tailored as possible.
- Disease activity should be monitored regularly based on objective markers.
Surgical Managment of Chrons
Surgical intervention alone cannot cure Crohn disease and is last resort to avoid complications in which significant amounts of bowel are lost (e.g., short bowel syndrome)!
Overview
- Minimally-invasive resection of affected and nonfunctional intestinal loops while preserving as much intestinal length and function as possible
- Indicated when medical therapy fails or patient develops severe complications (e.g., obstruction, stricture, abscess)
Methods
- Strictureplasty
- A surgical procedure that opens up a bowel stricture without having to resect the bowel (bowel-sparing technique)
- Indicated after multiple resections
- Limited resection (e.g., proctocolectomy): in case of obstructions or strictures
Chrons Complications
- Colorectal cancer (especially in the case of pancolitis)
- Short bowel syndrome and associated issues after surgery
- Stenosis/strictures → bowel obstruction
- Primary sclerosing cholangitis
- Impaired bile acid reabsorption
- Bile acid diarrhea
- Bile acid malabsorption → steatorrhea and deficiencies in fat-soluble vitamins
- Abscess formation/phlegmons
- Intestinal fistulas and abscesses
Chrons VS Ulcerative Colitis
Surgery
Chrons
Noncurative surgery may become necessary to alleviate symptoms
UC
Curative surgery possible (proctocolectomy)
Chrons VS Ulcerative Colitis
Histology
Chrons
- Transmural inflammation
- Noncaseating granulomas
- Giant cells
- Lymphoid aggregates
UC
- Confined to mucosa and submucosa
- No granulomas
Chrons VS Ulcerative Colitis
Diagnostic Findings
Chrons
- Cobblestone sign
- Pinpoint lesions
- Snail trails
- Creeping fat
- String sign
UC
- Friable mucosa
- Mucosal ulcerations can be deep or superficial
- Crypt abscesses
- Loss of haustra (lead pipe sign)
Chrons VS Ulcerative Colitis
Pattern of Inflamation
Chrons
- Discontinuous (skip lessions)
UC
- Continuous
Chrons VS Ulcerative Colitis
Antibodies
Chrons
- ASCA
UC
- p-ANCA
Chrons VS Ulcerative Colitis
Cancer Risk
Chrons
- Small intesine
- colon
- non-hodgkin lymphoma
UC
- Cholangiocarcinoma
- colorectal cancer
Chrons VS Ulcerative Colitis
Complications
Chrons
- abscess
- strictures
- perianal fissures
UC
- toxic megacolon
- perforation
- fulminant colitis
Chrons VS Ulcerative Colitis
Fistulas
Chrons
- Common
UC
- rare
Chrons VS Ulcerative Colitis
Extraintestinal Manifestations
Chrons
- nephrolithiasis
- cholelithiasis
UC
- primary sclerosing cholangitis
Chrons VS Ulcerative Colitis
Physical Exam
Chrons
- Mostly constant pain in RLQ
- Palpable abdominal mass
- Low-grade fever
UC
- Painful defecation, pain located in LLQ
- Abdominal cramps and tenderness
- Tachycardia
- Orthostatic hypotension
Chrons VS Ulcerative Colitis
Nutritional Status
Chrons
Poor/Malnurished
UC
Normal
Chrons VS Ulcerative Colitis
Stool
Chrons
- Increased
- Typically nonbloody, watery diarrhea
UC
- Greatly increased
- Bloody diarrhea with mucus
- Tenesmus
- Urgency
Ulcerative Colitis Epidemiology
PrevalenceEthnicity
- Higher in the white than in the black, Hispanic, or Asian populations
- Highest among individuals of Ashkenazi Jewish descent.
Peak incidence
- 15–35 years
Ulcerative Colitis
Pathophysiology
Dysregulation of the immune system:
- upregulation of lymphatic cell activity (T cells, B cells, plasma cells) →
- enhanced immune reaction and cytotoxic effect →
- inflammation with local tissue damage (ulcerations, erosions, necrosis)
- Autoantibodies (pANCA) against cells of the intestinal epithelium
- Ascending inflammation beginning in the rectum and spreading continuously proximally throughout the colon
Ulcerative Colitis Risk Factors
- Genetic predisposition (e.g., HLA-B27 association)
- Ethnicity (white populations, individuals of Ashkenazi Jewish descent)
Ulcerative Colitis
Intestinal Symptoms
- Bloody diarrhea with mucus
- Fecal urgency
- Abdominal pain and cramps
- Tenesmus
Tenesmus
distressing and persistent but ineffectual urge to empty the rectum or bladder
Ulcerative Colitis Extraintestinal Symptoms
- Skeletal: osteoarthritis, ankylosing spondylitis, sacroiliitis
- Ocular: uveitis; episcleritis
-
Biliary: primary sclerosing cholangitis (PSC)
- Rare for patients with UC to develop PSC, but up to 90% of all patients affected by PSC will also be affected by UC.
- Cutaneous: erythema nodosum, pyoderma gangrenosum, aphthous stomatitis,
- General: fatigue
Labs for Ulcerative Colitis
- ↑ ESR, ↑ CRP, leukocytosis
- Anemia
- Thrombocytosis in some cases
- ↑ Perinuclear ANCA (pANCA)
- In case of concurrent PSC: elevated gamma-glutamyl transferase
UC Endoscopic findings
Early stages
- Inflamed, erythematous, edematous mucosa
- Friable mucosa; bleeding on contact with endoscope
- Fibrin-covered ulcers
- Small mucosal ulcerations
- Loss of superficial vascular pattern
Chronic disease
- Loss of haustra
-
Pseudopolyps
- Raised areas of normal mucosal tissue that result from repeated cycles of ulceration and healing
Imaging for Ulcerative Colitis
Plain radiography
- Loss of colonic haustra (lead pipe appearance)
Barium enema radiography
- Pseudopolyps
Ulcerative Colitis Tx
- Oral/ topical 5-ASAs (5-aminosalicylic acid derivatives)
- Oral/ Topicalcorticosteroids
- Anti-TNF therapy; infliximab
- surgical proctocolectomy with an ileal pouch-anal anastomosis
Ulcerative Colitis Complications
- Gastrointestinal bleeding (both acute and chronic)
- Toxic megacolon
- Perforation
- Fulminant colitis; abdominal pain
- ↑ Risk of cancer (see colorectal carcinoma)
- Prevention: Screening colonoscopy with biopsies every 1–3 years starting 8 years after the initial diagnosis to screen for colorectal cancer
Bowel Obstruction
Interruption of the normal passage of bowel contents either due to a functional decrease in peristalsis or mechanical obstruction.
- Paralytic ileus: is a temporary disturbance of peristalsis in the absence of mechanical obstruction.
- Mechanical bowel obstruction: is due to a structural barrier.
Mechanical Bowel Obstruction
Clincal Features: Exam Findings
SBO/ LBO
- Dehydration and possible hypovolemia
- Diffuse abdominal tenderness
- Tympanic percussion
- Increased high-pitched, tinkling bowel sounds (early) or absent bowel sounds (late)
- Collapsed, empty rectum on digital rectal examination
Mechanical Bowel Obstruction
Clincal Features: Distentions
SBO
- Less Significant
LBO
- Early and Significant
Mechanical Bowel Obstruction
Clincal Features: Constipation
SBO
- Late Onset
LBO
- Early ONset
Mechanical Bowel Obstruction
Clincal Features: Vomiting/ Nausea
SBO
- Early onset
- Large volume
- Billious
LBO
- Late Onset
- Initially Billious
- Progresses to fecal vomiting
Mechanical Bowel Obstruction
Clincal Features: Pain
SBO
- Colicky
- Periumbilical
LBO
- Colicky or Constant
Mechanical Bowel Obstruction
Pediatric Causes
SBO
- Congenital intestinal atresia
- Intussusception
- Congenital strictures and bands
LBO
- Hirschsprung disease
- Congenital strictures and bands
- Meconium ileus
- Rectal atresia
Mechanical Bowel Obstruction
Most Common Causes
SBO
- Adhesions (e.g., prior abdominal surgery, abdominal tuberculosis)
- Incarcerated hernias: second most common
LBO
- Malignant tumors (e.g., colorectal carcinoma)
- Volvulus: second most common
Mechanical Bowel Obstruction
Diagnostics Labs
If recurrent vomiting
- Hypochloremic hypokalemic metabolic alkalosis
- Hyponatremia
If bowel strangulation
- Metabolic acidosis
- Hyperkalemia
Mechanical Bowel Obstruction
Diagnostic Imaging
Abdominal series
- hemodynamically unstable patients
- Dilatation of bowel loops proximal to the obstruction
- Minimal/no air within the bowel loops distal to the obstruction
- Stepladder sign (x-ray)
CT abdomen and pelvis
- hemodynamically stable patients
Abdominal ultrasound
- Pendular peristalsis
- Keyboard sign
Barium or water-soluble contrast enema
- Bird beak sign seen in volvulus
- Apple core sign seen in colonic malignancy
Keyboard Sign
- hyperechoic finger-like projections within the bowel lumen are the plicae circulares
- resemble the keys of a keyboard and are a sign of bowel obstruction
- The result of edema of the valvulae conniventes (circular mucosal folds in the wall of the jejunum).
Stepladder sign (x-ray)
- Multiple air-fluid levels and a stacked appearance of dilated small bowel loops
- Best seen on an erect abdominal x-ray
Mechanical Bowel Obstruction Tx
Conservative management
- Partial or Complete with no signs of ischemia/necrosis
- Fluid resuscitation, correction of electrolyte imbalance
- Intestinal decompression: nasogastric tube insertion
- Bowel rest (NPO)
- Peristalsis-inducing medication- contraindicated in complete.
Surgery
- Complete bowel obstruction with signs of ischemia/necrosis or clinical deterioration
Paralytic Illeus
Etiology
- Most common “5 Ps”: Peritonitis, Postoperative, low Potassium, Pelvic and spinal fractures, and Parturition
- Other:
- Endocrine Abnormalities
- Neuropathy
- Vascular Diseasse
- Inflamation of intra abdominal organts
- Drugs (anticholinergics, opiods, antidepressants)
Paralytic Illeus
Clinical Features
- Continuous (noncolicky) abdominal pain or discomfort
- Nausea, vomiting
- Abdominal distention
- Percussion: tympany
- bowel sounds are absent (silent abdomen)
Paralytic Illeus
Diagnostics
Laboratory
- Leukocytosis with left shift suggests intestinal infection or ischemia.
- Hypokalemia, hypomagnesemia
Imaging
-
Abdominal x-ray: best initial test
- Generalized small and large bowel gaseous distention
- Visible gas shadows in the rectum
- retroperitoneal hemorrhage; obliteration of the psoas muscle outline
Paralytic Illeus
Treatment
Conservative treatment
- no signs of localized or diffuse sepsis (e.g., appendicitis, secondary peritonitis)
- Bowel rest
- Nasogastric tube insertion
- IV fluids and electrolyte repletion
- Stop or decrease causative medications (e.g., opioids).
Surgical intervention: in patients with signs of peritonitis
Bowel Obstruction Complications
Bowel ischemia
Bowel perforation
Peritonitis
