General Surgery in the GI Tract Flashcards
Which GI disorders are associated with pain within the RUQ?
- Biliary colic
- Cholecystitis/cholangitis
- Duodenal ulcer
- Liver abscess
- Portal vein thrombosis
- Acute hepatitis
- Nephrolithiasis
- RLL pneumonia
Which GI disorders are associated with pain within the epigastrium?
- Acute gastritis/GORD
- Gastroparesis
- Peptic ulcer disease/perforation
- Acute pancreatitis
- Mesenteric ischaemia
- Abdominal aortic aneurysm
- Aortic dissection
- Myocardial infarction
Which GI disorders are associated with pain within the LUQ?
- Peptic ulcer
- Acute pancreatitis
- Splenic abscess
- Splenic infarction
- Nephrolithiasis
- LLL Pneumonia
Which GI disorders are associated with pain within the RLQ?
- Acute appendicitis
- Colitis
- IBD
- Infectious colitis
- Ureteric stone/pyelonephritis
- PID/Ovarian Torsion
- Ectopic pregnancy
- Malignancy
Which GI disorders are associated with suprapubic/central pain?
- Early appendicitis
- Mesenteric ischaemia
- Bowel obstruction
- Bowel perforation
- Constipation
- Gastroenteritis
- UTI/Urinary retention
- PID
Which GI disorders are associated with LLQ pain?
- Diverticulitis
- Colitis
- IBD
- Infectious colitis
- Ureteric stone/pyelonephritis
- PID/Ovarian torsion
- Ectopic pregnancy
- Malignancy
Which two main arteries supply the small intestine?
Coeliac artery
Superior mesenteric artery
Which arteries supply the colon?
SMA
IMA
Which artery supplies the rectum?
Internal iliac artery
What happens in bowel ischaemia?
In bowel ischaemia there is reduced blood flow and hypoperfusion to the gastrointestinal tract, predominantly due to thromboembolic events.
What are the presentations associated with bowel ischaemia?
- Sudden onset crampy abdominal pain
- Severity of pain depends on the length and thickness of colon affected
- Bloody, loose stool
- Fever, signs of septic shock
Partially altered blood is usually associated with which region of the GI tract?
Colon
Melaena is associated with which region of the GI tract?
Proximal small bowel
What are the risk factors for bowel ischaemia?
- Age >65 years
- Cardiac arrythmias (atrial fibrillation can potentiate the formation of clots due to turbulent flow, embolus into the SMA), and atherosclerosis.
- Hypercoagulation/thrombophilia
- Vasculitis
- Sickle cell disease
- Profound shock – hypotension
Why are cardiac arrythmias linked with bowel ischaemia?
atrial fibrillation can potentiate the formation of clots due to turbulent flow, embolus into the SMA
What is the main cause of acute mesenteric ischaemia?
Occlusive due to thrombo-emboli
What are the differences in onset between acute mesenteric ischaemia and ischaemia colitis?
Sudden onset v more mild and gradual
Moderate pain and tenderness is associated with what type of ischaemia?
Ischaemia colitis
What is the primary cause of ischaemia colitis?
Due to non-occlusive low flow states, or atherosclerosis
What investigations are conducted in a patient with suspected bowel ischaemia?
FBC - neutrophillic leuocytosis
VBG - Lactic acidosis - accumulation of lactate within the blood associated with late-stage mesenteric ischaemia (necrotic bowel)
An FBC in bowel ischaemia reveals what?
Neutrophillic leucocytosis
A VBG in bowel ischaemia will reveal what?
Lactic acidosis, an accumulation of lactate within the blood
What imaging is used in detecting bowel ischaemia?
CT angiogram
What does CTAP detect in bowel ischaemia?
Detects any vascular stenosis and disrupted flow within the vasculature using an arterial contrast.
• ‘Pneumatosis intestinalis’ (Transmural ischaemia/infarction)
• Ischaemic: Thumbprint sign (unspecific sign of colitis).
Colonic thickening
What is pneumatosis intestinalis?
Transmural ischaemia/infarction
What does a ‘thumbprint sign’ suggest?
Ischaemia
What conservative management options for bowel ischaemia?
- IV fluid resuscitation
- Bowel rest (Nil by mouth)
- Broad-spectrum antibiotics – Colonic ischaemia can result in bacterial translocation and sepsis.
- NG tube for decompression – in concurrent ileus (Absent peristalsis)
- Treat/manage underlying cause
- Serial abdominal examination and repeat imaging
What is ileus?
Absent peristalsis
What is the surgical management for bowel ischaemia?
Exploratory laparotomy: Resection of necrotic bowel +/- surgical embolectomy or mesenteric arterial bypass.
Endovascular revascularisation: Balloon angioplasty/thrombectomy. In patients without signs of ischaemia.
What warrants a patient for surgical management of bowel ischaemia?
- Small bowel ischaemia
- Signs of peritonitis or sepsis
- Haemodynamic instability
- Massive bleeding
- Fulminant colitis with toxic megacolon
What is explorative laparotomy?
Resection of necrotic bowel +/- surgical embolectomy or mesenteric arterial bypass.
What is endovascular revascularisation?
Balloon angioplasty/thrombectomy. In patients without signs of ischaemia.
What is acute appendicitis?
Acute inflammation of vermiform appendix , predominantly due to obstruction of the lumen of the appendix
What are the presentations of acute appendicits?
- Initially periumbilical pain that migrates to the right lower quadrant.
- Anorexia
- Nausea +/- vomiting
- Low grade fever
- Change in bowel habit
What is McBurney’s point?
Tenderness in the RLQ (lateral 1/3 of a hypothetical line drawn from the right ASIS to the umbilicus.
What is Blumberg sign?
Rebound tenderness in the right iliac fossa
What is Rovsing sign?
RLQ pain elicited on deep palpation of the LLQ.
What is Psoas sign?
RLQ pain elicited on flexion of right hip against resistance
What is Obturator Sign?
RLQ pain on passive internal rotation of the hip & knee flexion.
What are the blood signs with acute appendicits?
- FBC: Neutrophilic leucocytosis
- Increased CRP
- Urinalysis: Possible mild pyuria/haematuria
- Electrolyte imbalances in profound vomiting
What imaging is associated with the diagnosis of acute appendicitis?
- CT: Gold standard first line of investigation in adults >50.
- USS: Children/pregnancy/breastfeeding
- MRI: Pregnancy if USS inconclusive
What is the conservative management for acute appendicitis?
- IV Fluids, Analgesia IV or PO antibiotics
- In abscess, phlegmon or sealed perforation
- Resuscitation + IV antibiotics +/- percutaneous drainage.
What scoring criteria is used for assessing acute appendicitis?
Alvarado score
What Alvarado score categorises an increased likelihood of acute appendicitis?
> 7
What is a phlegmon?
Phlegmon describes inflammation of soft tissue that transmits deep to the skin or inside the body.
What is the surgical management for laparscopic appendicetomy?
- Trocar placement
- Exploration of RIF & identification of appendix
- Elevation of appendix + division of mesoappendix (containing artery)
- Base secured with endoloops and appendix is divided.
- Retrieval of appendix with a plastic retrieval bag.
- Careful inspection of the rest of the pelvic organs/intestines
- Pelvic irrigation (wash out) + haemostasis
- Removal of trocars + wound closure
What are the advantages of laparscopic appendicetomy over open?
- Less pain
- Lower incidence of surgical site infection
- Decreased length of hospital stay
- Earlier return to work
- Overall costs
- Better quality of life scores
What is bowel obstruction?
In small bowel obstruction there is a mechanical disruption in the patency of the gastrointestinal tract – emesis (vomiting), absolute constipation and abdominal pain.
In large bowel obstruction: A mechanical interruption to the flow of intestinal contents.
What are the five main causes of small bowel obstruction?
Adhesions Neoplasia Incarcerated hernia Crohn's disease Other
What are the main causes of large bowel obstruction?
Colorectal carcinoma Volvulus Diverticulitis Faecal impaction Hirschsprung disease
What type of pain is associated with small bowel obstruction?
Colicky, and central
How would you describe vomiting in small obstruction?
Early onset, large amount, bilious
How would you describe vomiting in large bowel obstruction?
Late onset
Initially bilious
Progresses to faecal vomiting
What features suggest strangulation?
- Change in character of pain from colicky to continuous
- Tachycardia
- Pyrexia
- Peritonism
- Bowel sounds absent or reduced
- Leucocytosis
- Increased C-reactive protein
What is a hernia?
A hernia refers to which an organ is displaced and protrudes through the wall of the cavity containing it.
What are the three types of GI hernias?
Neck of Sac
Strangulated hernia
Richter’s hernia
What is a neck of sac hernia?
As a consequence of the tight neck, the vasculature becomes compromised.
• Proximal bowel becomes distended due to obstructed flow
• Neck of a large hernia sac is transected at the midpoint of the inguinal canal.
What is a strangulated hernia?
A section of bowel protrudes through a weakened area of abdominal muscle, the surrounding muscle compresses around the tissue, compromising the blood supply.
• Venous return is impaired.
• Oedematous Increase’s blood pressure to prevent arterial flow into the affected area.
• Manifests as hypoperfusion and bowel ischaemia.
What is a Richter’s hernia?
Richter hernia is a herniation of only a portion of the circumference of the bowel wall through the fascial defect.
• There is continuous colonic flow of chyme throughout the bowel without strangulation.
What blood tests are performed in a patient with bowel obstruction?
- WCC/CRP: Normal (Raised - suspect of strangulation/perforation).
- U&E: Electrolyte imbalance
- VBG: Vomiting – Low chloride and potassium + metabolic alkalosis
- VGG if strangulation: Metabolic acidosis (Lactate elevated)
What imaging is performed in a patient with suspected bowel obstruction?
Erect CXR/AXR
• Small bowel: Dilated small bowel loops >3cm proximal to the obstruction (central).
• Large bowel: Dilated large bowel >6cm (caecum >9cm) predominantly peripheral.
• CT abdo/pelvis Transition point, dilation of proximal loops -IV+/-oral contrast if possible.
What are the characteristic imaging patterns for a small bowel obstruction?
- Ladder pattern of dilated loops and their central position
* Striations that pass completely across the width of the distended loop produced by the circular mucosal folds.
What are the characteristic features of a large bowel obstruction on an X-ray?
Large Bowel Obstruction
• Distended large bowel tends to lie peripherally
• Show haustrations of taenia coli – do not extend across whole width of bowel
Why is a CT scan conducted in a patient with a bowel obstruction?
A CT scan is conducted in order to localise the exact site of obstruction.
• Detect obstructing lesions and colonic tumours
• May diagnose unusual hernias (obturator hernias)
What is the Supportive management for bowel obstruction?
In patients with no signs of ischaemia/no signs of clinical deterioration.
Supportive management
• NBM, IV peripheral access with large bore cannula- IV fluid resuscitation.
• IV analgesia, IV anti-emetics, correction of electrolyte imbalances
• Nasogastric tube for decompression (removes chance of aspiration pneumonia), urinary catheter for monitoring output
• Introduce gradual food intake if abdominal pain and distention improve.
What is the conservative management for bowel obstruction?
- Faecal impaction: Stool evacuation (manual, enemas, endoscopic)
- Sigmoid volvulus (obstruction caused by twisting of intestines): Rigid sigmoidoscopic decompression – removal of fluid results in bowel collapse to straighten and improve distention.
- SBO: Oral gastrograffin (Highly osmolar iodinated contrast agent) – can be used to resolve adhesional small bowel obstruction.
What is a sigmoid volvulus?
obstruction caused by twisting of intestines
How can a sigmoid volvulus be resolved?
Rigid sigmoidoscopic decompression – removal of fluid results in bowel collapse to straighten and improve distention.
What is oral gastrograffin?
Highly osmolar iodinated contrast agent
What are the indications for the surgical management of bowel obstruction?
- Haemodynamic instability or signs of sepsis
- Complete bowel obstruction with signs of ischaemia (VBG detects elevated lactate).
- Closed loop obstruction
- Persistent bowel obstruction > 2 days despite conservative management
What operations are performed for bowel obstruction?
- Exploratory laparotomy/laparoscopy
- Restoration of intestinal transit (depending on intra-operation findings)
- Bowel resection with primary anastomosis or temporary/permanent stroma formation
What is a GI perforation?
Gastrointestinal perforation occurs when a hole forms through the stomach, large bowel or small intestine.
What are the symptoms associated with a GI perforation?
- Sudden onset severe abdominal pain associated with distension
- Diffuse abdominal guarding, rigidity, rebound tenderness.
- Pain aggravated by movement
- Nausea, vomiting, absolute constipation
- Fever, tachycardia, tachypnoea, hypotension
- Decreased, or absent bowel sounds
What is rebound tenderness?
A clinical sign in which there is pain upon removal of pressure rather than application of pressure to the abdomen.
What symptoms are associated with a perforated peptic ulcer?
Sudden epigastric or diffuse pain
Referred shoulder pain
Hx of NSAIDs, steroids, recurrent epigastric pain
What symptoms are associated with a perforated diverticulum?
Lower left quadrant pain
Constipation
Insidious, perforations seal off, perorated
What symptoms are associated with a perforated appendix?
Migratory pain
Anorexia
Gradual worsening RLQ pain
What symptoms are associated with a perforated malignancy?
Change in bowel habit
Weight loss
Anorexia
PR bleeding
What blood investigations are conducted in patients with GI perforations?
- FBC: Neutrophilic leucocytosis
- Possible elevation of urea, creatinine
- VBG: Lactic acidosis
What causes an inflated-lift diaphgram?
GI perforation, gas accumulation
What imaging is performed for a GI perforation?
- Erect CXR: Subdiaphragmatic free air (pneumoperitoneum)
- CT abdo/pelvis Pneumoperitoneum, free GI content, localised mesenteric fat stranding
- Can exclude common differential diagnoses such as pancreatitis
What are the supportive management plans for GI perforations?
- NBM & nasogastric tube
- IV peripheral access with large bore canula – IV fluid restriction
- Broad spectrum antibiotics
- IV proton-pump inhibitors
- Parenteral analgesia & anti-emetics
- Urinary catheter
What are the conservative management plans for GI perforations?
Conservative management in localised peritonitis without signs of sepsis (Very rare)
• IR – guided drainage of intra-abdominal collection
• Serial abdominal examination & abdominal imaging for assessment.
What are the surgical interventions for a GI perforation?
- Exploratory laparotomy/laparoscopy
- Primary closure of perforation with or without omental patch (most common in perforated peptic ulcer)
- Resection of the perforated segment of the bowel with primary anastomosis or temporary stoma.
- Obtain intra-abdominal fluid for MC&S, peritoneal lavage
- If perforated appendix Lap or open appendicectomy
- If malignancy Intraoperative biopsies.