Bariatric surgery complications

Background

  • Rou-en-Y - malabsorptive and restrictive physiology 
  • Gastric Sleeve - restrictive
  • Biliopancreatic diversion
  • Vertical banded gastroplaty - now historical as replaced by LAP band 
  • Lap Band Complications

Clinical Features

  • abdominal pain, food intolerance
  • sepsis, abnormal VS

Differential Diagnosis

Early

  • VTE, PNA, UTI, SBO, etc
  • Roux-Limb Obstruction
    • NV, abd pain
    • causes acute Gastric dilation
    • surgical emergency
    • IR decompression possible
  • Anastamotic Leak
    • abdominal exam often non-acute due to habitus
  • Intra-abdominal bleeding
    • may bleed into GI tract and only visualized on endoscopy

Late

  • UGIB
    • resuscitate in stanrd fashion
    • emergent endoscopy
    • often bleed from staple lines, ulcers
  • Anastomotic Leak or Stricture
    • progressive inability to tolerate PO
    • abdominal pain
    • solids first then liquids
    • needs UGI then likely endoscopy
  • Marginal Ulcer
    • epigastric pain and dyspepsia
    • upper endoscopy
    • manage with acid suppression
  • Internal hernia
    • obstructive or nonobstructive
    • crampy intermitten abd pain radiating to back
    • can have nl abd exam
    • may strangulate herniated bowel
    • w/u CT AP and UGI
    • CT findings swirl sign, intussuscepted bowel
    • needs surgery early
  • Nurtitional Complications
    • consider pts immunosuppressed due to malnourishment
    • Anemia, neuropathy, fractures, hypercalcemia
    • Wernickes encephalopathy
    • Dumping syndrome

Diagnosis

  • CT AP - use PO & IV contrast
    • pts often cannot tolerated full 1L of PO contrast
    • sip as much contrast as possible in 3hrs then CT    
    • weight limit of CT scanner often exceeded
    • can use Gastrograffin UGI series instead
  • UGI series
    • beware GI pouch limits on contrast volume
    • usefull for perforation, internal hernia, stricture, leak

Specific Surgeries

Roux-en-Y gastric bypass

  • Creation of a small gastric pouch and an anastomosis to the jejunum
  • Gastric remnant distension[1]
    • Remnant is a blind pouch that may become distended with paralytic ileus
    • Potential rupture → severe peritonitis
    • 3.9% leak rate for RYGB; overall mortality 0.6%
    • Jejunojejunostomy leak a/w 40% mortality
    • S/s: pain, hiccups, LUQ tympany, shoulder pain, abd distention
    • Dx: XR shows large gastric air bubble vs CT
    • Tx: emergent operative decompression with percutaneous drainage
  • Stomal Stenosis
    • Occurs in 6-20% of RYGB pts
    • Possibly related to tissue ischemia or tension on GJ anastomosis
    • Presentation several weeks after surgery
    • S/s: N/V, dysphagia, GERD, inability to tolerate PO
    • Dx with endoscopy vs UGI series vs CT
  • Marginal Ulcers
    • Occur in 0.6-16% of RYGB pts
    • Acid injury to jejunum
    • Causes: poor perfusion 2/2 tension/ischemia, increase gastric acid exposure, NSAID use, H pylori infection
    • S/s: Nausea, pain, bleeding +/- perforation
    • Dx with endoscopy
    • Patients typically medically managed
  • Cholelithiasis
    • 38% of RYGB pts
      • Risk reduced to 2% if ursodiol given as post-op ppx
      • Some surgeons perform prophylactic cholecystectomy with RYB procedure
    • Rapid weight loss increases lithogenicity of bile
    • Dx: U/S or MRCP
  • Hernias
    • Ventral hernias (0-1.8% in lap RYGB)
    • Internal hernias (0-5%)
      • Intermittent and may be difficult to detect via CT
      • Suspected may require urgent surgical exploration lest patient has strangulated pathology
  • Dumping Syndrome
    • Occur in up to 50% of pts when high levels of carbohydrates are ingested
    • Early dumping syndrome
      • Occurs when pylorus is either removed or bypassed, allowing hyperosmolar stomach chyme to "dump" into the small intestine.
      • Hyperosmolality of food → fluid shifts into GI lumen → colicky and pain, diarrhea, nausea, tachycardia, diaphoresis, dizziness, syncope.
      • Tx: Diet modification to avoid high simple sugars
    • Late dumping syndrome
      • Insulin response that leads to hypoglycemia 2-3 hours after meal
      • S/s: dizziness, fatigue, diaphoresis, weakness

Gastric Banding

  • Placement of restrictive ring over the gastric cardia near the GE junction
  • Lowest mortality rate among all bariatric surgeries (0.05% mortality)
  • Stomal Obstruction
    • Early complication; occurs in 14% go GB pts
    • Typically 2/2 inclusion over excess perigastric fat vs tissue edema vs inappropriate sized band
    • S/s: N/V, inability to tolerate PO
    • Dx: UGI series vs CT
    • If due to edema, may be treated with NG tube decompression until swelling improves
      • May require surgical revision if above unsuccessful
  • Port infection
    • 0.3-9% of GB patients
    • a/w band erosion
    • Tx: Replacement of port if isolated infection vs band if more extensive
  • Band Erosion
    • Up to 7% of GB pts
    • Erodes through gastric wall 2/2 wall ischemia vs mechanical stress from band
    • Occurs on average 22 months after surgery
    • S/s: e/o infection, failure to lose weight, N/V; epigastric pain and hematemesis
    • Dx: Endoscopy vs CT
    • Tx: Band removal
  • Band Slippage/gastric prolapse
    • 2-14% of pts
    • Either anterior or posterior prolapse
    • S/s: Food intolerance, epigastric pain, acid reflux
    • Dx: Upper GI series vs CT
    • Tx: Emergent surgery
  • Esophageal dilatation
    • Up to 10% of pts
    • a/w over-inflated bands or excessive food intake
    • S/s: Food/saliva intolerance, reflux, epigastric pain
    • Dx: UGI series vs CT
    • Tx: Fluid removal from band initially and behavioral modifications
  • Hiatus hernia
    • Results in refractory reflux

Sleeve gastrectomy

  • Creates sleeve out of the stomach and removes portion of greater curvature of stomach
  • Complication rate 3-24%; mortality 0.39%
  • Bleeding
    • Typically occur from the staple line
  • Stenosis
    • Can lead to gastric outlet obstruction
    • S/s: Dysphagia, vomiting, dehydration, inability to tolerate PO
    • Dx: UGI series vs CT
    • Tx: Endoscopic dilatation vs surgical intervention depending on involvement
  • Gastric leaks
    • Up to 5.3% of pts; most serious complication a/w sleeve gastrectomy
    • 2/2 poor healing in setting of inadequate blood supply vs weakness at staple line vs gastric-wall heat ischemia from cautery
    • Tx: surgical repair vs percutaneous drainge/abx/NPO
  • Reflux
    • Common post-op complication
    • Treated medically initially with eventual RYGB for refractory cases

See Also

References

  1. Lee S, Carmody B, Wolfe L, Demaria E, Kellum JM, Sugerman H, Maher JW. Effect of location and speed of diagnosis on anastomotic leak outcomes in 3828 gastric bypass cases. J Gastrointest Surg. 2007;11(6):708.