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Small Bowel ObstructionJosé Luis Cortés Sánchez
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Epidemiology Most frequently encountered surgical disorder
of the small intestine Anatomic relationship to intestinal wall: 1.- Intraluminal: 2.- Intramural 3.- Extrinsic
Intraabdominal adhesions related to prior abdominal surgery account for up to 75% of cases
300,000 patients are estimated to undergo surgery to treat them annually
From 1988 to 2007 there was no decrease in this rate
Ongoing problems with this “old” disease
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Other causes: Hernias, malignant, Chron’s
Few are due to primary bowel tumors
Congenital usually become evident during childhood, but sometimes are not
i.e. Intestinal malrotation, mid-gut volvolus (without history)
Superior mesentric artery Sx. (rare etiology)
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
PathophysiologyGas and fluid acumulate
Intestinal activity increases Pain and diarrhea
Swallowed air and produced
Swallowed liquids and GI secretions Bowel distends IM/ IL pressure rises
Motility is eventually reduced
Luminal flora changes
If IM pressure high enough perfusion is impaired ischemia - necrosis
Strangulated bowel obstructionBrunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Partial
Allows passage of some fluid and gas
Event progression occur more slowly
Less likely to become strangulated
Closed-loop
Particularly dangerous E.g. volvolus Rapid rise in luminal
pressure Rapid progression to
strangulation
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Clinical presentation Colicky abdominal pain, nausea, vomiting,
obstipation More vomiting w/proximal than distal Feculent? bacterial overgrowth (more
established) Continuos passage of flattus/stool >6-12
hours= Partial
Signs Abdominal distention (more if distal) Initially hyperactive bowel sounds then
minimal Lab:
Intravascular volume depletion Hemoconcentration Electrolyte abnormalities Mild leukocytosis
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Strangulated Abd. pain disproportionate to degree of abd
findings -suggestive of intestinal ischemia
Tachycardia, Localized abd tenderness Fever Marked leukocytosis Acidosis
Alert!
Prompt early surgical intervention!
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Diagnosis 1.-Distinguishing mechanical obstruction from
ileus 2.-Determine the etiology 3.-Discriminate partial from complete 4.-Discriminate simple from strangulated
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
History Prior abd operations Abd disorders (cancer, IBD) Meticulous search for hernias(inguinal, femoral) Dx.- confirmed by radiographic exams
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Abdominal series Rx of the abdomen patient in supine Abdomen w/patient upright Rx of the chest w/patient in upright
Most specific triad:-Dilated small bowel loops (>3 cm in diameter)-Air-fluid levels on upright-Paucity of air in colon
S= 70-80%E= lowDDX.-
Ileus, colonic obstruction
FN= proximal; fluid but no gas Closed-loop
Despite these limitations, abdominal radiographs remain an important study in patients with suspected small bowel obstruction because of their wide- spread availability and low cost
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
CT scan Discrete transition zonew/dilation of proximal Decompression of distally Contrast that doesn’t pass beyond transition Colon with little gas or fluid
S= 80-90%E= 70-90%
-CT may also provide evidence of closed-loop/strangulation--Closed-loop U-/C-shaped bowel+ radial messenteric vessels in torsion point
-StrangulationThickening of bowel wall, pneumatosis intestinalis, portal venous gas, mesenteric hazinessPoor uptake of IV contrast
CT also reveals the etiology
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Appearance of contrast in colon w(24hrs) is predictive of non-surgical resolution
Reduce overall length of hospitalization
S= 50% , for low-grade or partial
Small bowel series/ Enteroclysis can be helpful
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Therapy Marked depletion of IV volume –> fluid resuscitation is integral
to treatment Central venous o pulmonary artery catheter assist fluid
management (CVS or severe) Antibiotics? No data to support it
Isotonic fluid IV + Bladder catheter
NG tube to evacuate stomach. Not jejunum nor ileum
Decreases nausea, vomiting, distention, aspiration
“the sun should never rise and set on a complete bowel obstruction.”
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
nonoperative aproaches
R/O closed-loop ; neither intestinal ischemia
Observe closely and undergo serial exams
Early surgical intervention
Minimize the risk for strangulation
Morbimortality
Signs and lab tests and imaging don’t distinct between them
Goal? operate before onset of ischemiaA period of observation and NG decompression, provided no tachycardia, tenderness or WBC increases
Conservative therapy 1. Partial small bowel obstruction
2. Obstruction occurring in the early postoperative
3. Intestinal obstruction due to Crohn’s disease
4. Carcinomatosis
Strangulation is unlikely to occur. Succesful in 65-81% Of these 5-15% don’t improve at 48 hrs
Patients with partial obstruction thath do not improve at 48h should undergo surgery!0
-Occur in 0.7% patients undergoing laparotomy.
-Pelvic surgery, especially colorectal procedures, have the greatest
risk.
-Should be considered if
-symptoms of intestinal obstruction occur after the initial
return -Function fails to return within the expected 3 to 5 days after
-25-33% of patients with
-Even in cases in which the obstruction is related to recurrent malignancy,
palliative resection or bypass can be performed.
-Patients with obvious carcinomatosis pose a difficult challenge, given their
limited prognosis.
May be best achieved by a bypass procedureBrunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Adhesions lysed Tumors resected Hernias reduced and repaired.
The affected intestine should be examined, and nonviable bowel resected.
If the patient is hemodynamically stable, short lengths of bowel of questionable viability should be resected
Bowel of uncertain viability should be left intact and the patient re-explored in 24 to 48 hours in a “second- look” operation.
Criteria suggesting viability:
-normal color,-peristalsis, -marginal arterial pulsation
Operative procedure varies according to the etiology
Laparascopic procedure have a quicker recovery, less complications, and lower costs.
Distended loops of bowel can interfere with adequate visualization, early cases likely due to a single adhesion
Conversion rate to open surgery is between 17% and 33%
Outcomes Prognosis is related to the etiology Less than 20% of conservative patients will have a
readmission over the subsequent 5 years The perioperative mortality rate associated with
surgery for nonstrangulating small bowel obstruction is less than 5%,
Mortality rates associated with surgery for strangulating obstruction range from 8% to 25%.
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Brunicardi, F. C. (2015). Schwartz's Principles of Surgery. 10 Ed. McGrawHill Ed
Prevention
Good surgical technique, careful handling of tissue, and minimal use and exposure of peritoneum to foreign bodies form the cornerstone of adhesion prevention.
Colorectal or pelvic surgery, hospital readmission rates of greater than 30% over the subsequent 10 years
.
These measures alone are often inadequate.
Open surgery is associated with a 4x increase in risk of small bowel obstruction within 5 years of the index procedure
Seprafilm
INTESTINAL FISTULAS
fistula abnormal communication between two
epithelialized surfaces. internal fistula .- between two parts of the GI
tract or adjacent organs external fistula involves the skin or another
external surface epithelium. Over 80% of enterocutaneous fistulas represent
iatrogenic complications that occur as the result of enterotomies or intestinal anastomotic dehiscences.
Spontaneously without antecedent iatrogenic injury are Crohn’s disease or cancer. low-output fistulas
Entero- cutaneous fistulas that drain less than 200 mL of fluid per
day
high-output fistulas. those that drain more than 500 mL
of fluid per day
Pathophysiology Low-resistance enteroenteric bypass
malabsorption Enterovesicular Recurrent UTI’s Drainage from enterocutaneous irritates skin
excoriation Loss of enteric luminal contents (high-output)
dehydration, electrolyte abnormalities, malnutrition
Fistulas have the potential to close spontaneously, but:
Clinical
Presentation
Fever Leukocytosis prolonged ileus abdominal tenderness, wound infection
evident between the 5th-10th postoperative days.
initi
al si
gns.
Iatrogenic enterocutaneous fistulas
The diagnosis is obvious when drainage of enteric material occurs.
These fistulas are often associated with intraabdominal abscesses.
Diagnosis CT scanning following the
administration of enteral contrastMost useful initial test?
Leakage of contrast material from the intestinal lumen can be observed. Intraabdominal abscesses should be sought and drained percutaneously. -Small bowel series or
enteroclysis examination can be obtained to demonstrate the fistula’s site of origin in the bowel.
-Useful to R/O the presence of intestinal obstruction distal to the site of origin.
If the anatomy of the fistula is not clear on CT scanning?
A fistulogram,
Therapy 1. Stabilization.
Fluid and electrolyte resuscitation is begun. Nutrition is provided, usually through the parenteral route initially.
Sepsis is controlled with antibiotics and drainage of abscesses. The skin is protected from the fistula effluent with ostomy appliances
or fistula drains. 2. Investigation. The anatomy of the fistula is defined
3. Decision. Tx options considered, and timeline for conservative
4. Definitive management. surgical procedure 5. Rehabilitation.
Objective is to increase the probability of spotaneous closure.
Nutrition and time are the key components of this approach.
Most patients will require TPN
however, a trial of oral or enteral nutrition should be attempted in patients with low-output fistulas originating from the distal intestine.
Octreotide is a useful adjunct, particularly in patients with high-output fistulas; -reduces the volume of fistula output thereby facilitating fluid and electrolyte management.
Timing of Surgical Intervention.
2 to 3 months of conservative therapy before considering surgical intervention.
surgical intervention after this time period is associated with better outcomes and lower morbidity
90% of fistulas that are going to close do so within 5 weeks
fails to resolve during this period ?
fistula tract, together with the segment of intestine from which it originates, should be resected.
Simple closure of the opening in the intestine from which the fistula originates is associated with high recurrence rates.
Outcomes
“FRIEND” Foreign body within the fistula tract Radiation enteritis Infection/Inflammation at the fistula origin Epithelialization of the fistula tract Neoplasm at the fistula origin Distal obstruction of the intestine
Over 50% of intestinal fistulas close spontaneously.
153 cases of enterocutaneous
fistulas Majority were found to originate from the small bowel Patients having undergone 5 or + previous surgeries. 30-day mortality of approximately 4% 1-year mortality of 15%. Morbidity was over 80%. First surgical repair attempt was successful 70% of
cases
Some patients requiring up to three attempts at surgical repair.
closure of the abdominal fascia as an important factor in reducing rates of refistulization and postoperative mortality.Owen RM, Love TP, Perez SD, et al. Definitive surgical treatment of enterocutaneous fistula: outcomes of a 23-year experi- ence. Arch
Surg. 2012;15:1.
A 43-year-old woman comes to the emergency department with a 3-day history of abdominal distention, nausea, and vomiting. She also reports decreased urine output over the last 24 hours. She has a history of total abdominal hysterectomy 5 years ago for benign disease. She does not take any medications. Her pulse is 110 beats/minute. Her abdomen is distended and there is mild diffuse tenderness. Bowel sounds are hyperactive. The rest of her exam is normal. Serum electrolytes are sodium—140, chloride—90, bicarbonate—32, and potassium—4.0. Which of the following is the most appropriate initial intravenous fluid to administer to this patient?
A.-D5 1⁄2 normal saline with 40 mEq KCl/L B. Lactated Ringer’s solutionC. Normal salineD. Colloidal starch solutionE. 5% albumin in normal saline