Surgical Management of GI Tract Tutorial Flashcards
Case 1 - 84M Bowels have not opened for 3 days Steady weight Feals nauseous and anorexic Previously normal daily bowel motions
On examination -
Nothing unexpected
Empty rectum with smooth enlargement of prostate
Gossly swollen abdomen
PMH = arthritis of both hips, mild prostatic symptoms DH = no medications SH = ex-smoker
What is the likely differential?
Acute intestinal obstruction
Which is more likely - obstruction of small or large bowel? And why?
Large bowel or ‘low’ obstruction because:
No evidence of previous abdominal operation - previous abdominal surgery is the commonest cause of small bowel obstruction
No evidence of strangulated external hernia
No vomiting - vomiting is normally a symptom of small intestine obstruction or v. v. late sign of large bowel obstruction
Grossly distended abdomen - because of the size of the large bowel
Obstruction of small bowel = most likely to vomit up the fluids from the stomach, liver, etc.
Strangulated external hernia = common cause of small bowel obstruction
Small bowel obstruction unlikely as it is usually secondary to previous abdo operation
Distension of large bowel = greater than small bowel
What is the first lline of management of a suspected acute intestinal obstruction?
Morphine for pain
NGT - aspirated 300ml of green fluid
IV line inserted and started on IV fluids
What is the next suitable investigation for a suspected acute intestinal obstruction?
Erect and supine ABX
Erect = fluid level = points towards obstruction
Supine shows distended large bowel
What does the abdominal x-ray (ABX) demonstrate and what is the likely diagnosis?
Enormously distended oval gas shadow looped on itself to give a –> ‘best inner-tube sign’ OR ‘coffee bean sign’ = large bowel
Haustrae don’t extend across the width of the gas shadow, suggesting this is large intestine
Likely to be volvulus of sigmoid colon
What is the volvulus of sigmoid colon?
Loop of sigmoid colon gets twisted around each other - like turning a key, twists on each other
Forms closed loop - stops anything coming in our out of that section of the large bowel that has looped on itself and trapped itself
What conservative management is effective in treating the majority of patients with a sigmoid volvulus?
Sigmoidoscopy =sigmoidscope passed with the patient lying in the left lateral position with their knees up to their chest - scope can be flexible or rigid
Flatus tube = soft rubber rectal tube passed along sigmoidoscope
This usually untwists the volvulus = release of vast quantitied of flatus and liquid faeces
If conservative management using a sigmoidscope and flatus tube does not work, what is the risk of leaving it untreated?
Left untreated, the loop of sigmoid, with its blood supply cut off by the torsion, would undergo necrosis
Torsion = cut off blood supply = ischaemia and necrosis of that part of the large bowel
What is the next option if the rigid sigmoidscope and flatus tube did not work?
Flexible sigmoidoscopy = requires highly skilled endoscopists
What is the next option if flexible sigmoidoscopy fails?
Exploratory laparotomy and sigmoid colectomy (resection of necrotic dead bowel) + join colon with rectum OR end colostomy (Hartmann’s procedure - colon is pulled out through a cut in the left iliac fossa of the abdomen)
Iliostomy = distal ileum = pulled out of cut in the right iliac fossa of the abdomen
Why does Hartmann’s procedure exist? What are the complications of joining the colon with rectum after resection?
Can easily fall apart
Case 2 - 84M
PC = 1 day history of abdominal pain, nausea, breathlessness
PMH = COPD, ex-smoker for 3 years
On examination:
Pale and sweaty, BP 100/60, abdominal distension and periumbilical guarding, absent bowel sounds, eveything else normal
Blood tests show:
Low Hb, high WCC, high uea, high creatinine, high serum lactate and high CRP
What is the differential diagnosis and why?
AMI - acute mesenteric ischaemia
Ex-smoker = increased CVD risk Short history - sudden onset of symptoms Central pain with guarding No previous abdominal scar or hernia No bowel sounds = not working bowel Turbulent flow = more likely to clot Poor general condition Increased serum lactate = late sign of bowel ischaemia (metabolic acidosis)
What investigations should be ordered next for this patient’s suspected acute mesenteric ischaemia?
CT of abdo and pelvis with contrast
Because you can see:
Thrombus in arteries and veins
Abnormal enhancement of bowel wall = ischaemia
Presence of embolus or infarction of other organs = something is firing off emboli in the body
CT scan shows: normal aorta and SMA
However, as we go lower down the body, SMA at middle colic artery no longer lighting up with contrast = embolus or thrombus blocking the SMA
What does SMA supply?
SMA = small and large bowel around splenic flexure
Fluid filled ichaemic small bowel on CT
Bowel is not enhancing - contrast is not reaching that area of bowel so blood supply is not reaching that area of bowel
What is the management for this patient?
Emergency exploratory laparotomy = damage control = get to the bowel before necrosis OR if already necrotic, resect necrotic bowel
Restore blood flow via SMA to recover the ischaemic bowel
