General Surgery Flashcards
What is pancreatitis?
Definition – inflammation of the pancreas, usually due to autodigestion which results in necrosis. Most commonly caused by alcohol or gallstones in western countries.
What are the causes of pancreatitis?
I GET SMASHED • Idiopathic • Gall Stones • Ethanol • Trauma • Steroids • Mumps/Malignancy • Autoimmune • Scorpion sting/Spider bite • Hyperlipidaemia/hypercalcaemia/hyperparathyroidism • ERCP • Drugs (azathioprine, meslazine, Bendroflumethiazide, didanosine (HIV med) furosemide, pentamidine, steroids, sodium valproate and ACEi)
What are the clinical features and diagnostic criteria for pancreatitis?
2/3 criteria needed for clinical diagnosis
- Amylase greater than 3 times normal limit (if less that this but still raised – SBO and perforated duodenal ulcer are differentials)
- Pattern of pain starting epigastric and radiating to the back
- Diagnostic CT
Cullen’s bruising – oedema and bruising in umbilical region
Grey-turners sign – bruising up the flanks
Vomiting
Ileus
Fever
Ischaemic retinopathy (Purtscher retinopathy) – rare
How should suspected pancreatitis be investigated?
Serum amylase may give false positive and negative results i.e. also raised in pancreatic pseudocyst, mesenteric infarct, perforated viscus, acute cholecystitis, and diabetic ketoacidosis. Note the amylase level is not of prognostic value.
Serum lipase is more sensitive and specific and has a longer half life
Blood gas
FBC, U&Es and calcium, LFTs, LDH, albumin and blood sugar
Early USS to check for gall stones or other aetiology
CT to rule out perforated ulcer/cancer
MRCP (magnetic resonance cholangiopancreatography)
How do we assess the severity of pancreatitis?
There are multiple scoring systems used to quantify severe cases of pancreatitis which include Ranson score, APACHE II and Glasgow score.
Modified Glasgow scoring system If 3 or more let ITU know no matter how well the patient looks (PANCREAS) • PaO2 < 8kPa • Age > 55 • Neutrophilia > 15 • Calcium < 2 • Renal Function – Urea > 16 • Enzymes – LDH > 600 and AST > 200 • Albumin < 32 • Sugar > 10
How is acute pancreatitis managed?
ABCDE
Maintain enteral feeding to prevent bacterial translocation from the gut and to prevent malnutrition which patients are susceptible to
Analgesics with IV opioids (fluids also help with pain by reducing lactic acidosis)
Very aggressive fluid resuscitation with crystalloids, aim for urine output of > 0.5ml/kg/hr
Nutrition – NBM if clear reason, enteral nutrition if moderate or severe within 72 hours, parenteral nutrition only if enteral fails or is contraindicated
NO antibiotics unless clear indication e.g. infected pancreatic necrosis
Surgery
Aspiration and debridement if necrotic or cyst formation
Gall bladder removal if pancreatitis caused by gallstones.
ERCP early if stone is stuck.
What are the two main complications to be wary of when treating pancreatitis?
AKI due to large fluid movements
ARDS due to fluid build-up in lungs and enzyme damage from serum pancreatic enzymes
What are peripancreatic fluid collections and how are they managed?
Peripancreatic fluid collections – can develop into pseudocyst or abscess. Most resolve on their own but aspiration and drainage may be required.
What are pancreatic pseudocysts and how are they managed?
Pseudocysts – peripancreatic fluid that communicates with the ductal system and typically occurs 4 weeks post pancreatitis attack. Most resolve on their own but symptomatic cases may be observed for 12 weeks and if treatment is required then endoscopic or surgical cystogastrosomy or aspiration.
What is pancreatic necrosis and how is it managed?
Pancreatic necrosis – early surgical intervention should be avoided due to high mortality rate. Sterile necrosis should be managed conservatively. If infection is suspected fine needle
aspiration can be done.
What are pancreatic abscess and how are they managed?
Pancreatic abscess – collection of pus associated with the pancreas in the absence of necrosis. Typically, as a result of infected pseudocyst. Managed with trans gastric drainage or endoscopic drainage.
What are the common causes of chronic pancreatitis?
Alcohol most common Idiopathic Cystic fibrosis Hemochromatosis Ductal obstruction
What are the clinical features of chronic pancreatitis?
Epigastric pain typically 15-30mins after eating
Steatorrhea – usually 5-25yrs after symptoms
Diabetes mellitus – usually 20yrs after symptoms
What investigations should patients suspected of having chronic pancreatitis have?
Abdominal X-ray – speckled calcification in 30%
CT more sensitive
USS
Faecal elastase
How is chronic pancreatitis managed?
Pancreatic enzyme supplements Analgesia Antioxidants Insulin if required Diet – no alcohol and low fat
What are the 3 types of bowel ischaemia?
There are 3 main ischaemic bowel conditions
• Acute mesenteric ischaemia
• Chronic mesenteric ischaemia
• Ischaemic colitis
What are the risk factors of bowel ischaemia?
Increasing age
Atrial fibrillation (particularly for mesenteric)
Other causes of emboli – endocarditis or malignancy
Cardiovascular risk factors – smoking, hypertension, diabetes etc.
Cocaine – ischaemic colitis in young patients following cocaine use
How does bowel ischaemia present generally?
Abdominal pain Rectal bleeding Diarrhoea Fever Bloods typically show elevated WCC and lactic acidosis
What investigations should be done for bowel ischaemia?
AXR – thumbprinting sign seen in ischaemic colitis
CT scan is investigation of choice
What is acute mesenteric ischaemia and what are its specific features?
Typically, small bowel but can occur to lower GI tract due to an embolism blocking one of the arteries supplying the bowel. Sudden onset and severe symptoms, out of keeping with clinical findings.
How is acute mesenteric ischaemia managed?
Urgent surgery required
High mortality especially if surgery is delayed
What is chronic mesenteric ischaemia?
This is effectively intestinal angina, presents with nonspecific features of intermittent colicky pain, weight loss and an abdominal bruit.
What is ischaemic colitis and what are its specific features?
Typically, large bowel, due to multifactorial causes resulting in transient compromise of blood flow to the large bowel. This leads to inflammation, ulceration, and haemorrhage. Most commonly occurs in ‘watershed’ areas such as the splenic flexure (borders of territory supplied by both the SMA and IMA). Presentation is with transient, less severe symptoms including bloody diarrhoea.
What is seen on AXR in ischaemic colitis and why?
Thumbprinting seen on AXR due to mucosal oedema/haemorrhage
How is ischaemic colitis managed?
Conservative management required with supportive therapy
Surgery may be required in minority of cases if above measures fail
Indications include generalised peritonitis, perforation or ongoing haemorrhage
What can cause perforation of the bowel?
Peptic ulcers – Epigastric pain or back pain
Obstruction
Appendicitis
Crohn’s
Diverticulitis – most commonly perforates in the sigmoid
Trauma and foreign body
Colonoscopy
What are the clinical features of a perforated bowel?
Severe constant abdominal or epigastric pain
If in gut then gradual onset of pain if in stomach then sudden
Septic symptoms
Pain intensified by movement (rigid abdomen)
Nausea and vomiting and haematemesis
Rebound tenderness
Ceased bowl movements and flatus
How does location of pain change depending on where a perforation has taken place?
Intraperitoneal perforation – generalised abdominal pain
Retroperitoneal perforation – shoulder tip pain, back pain normal examination
Thoracic – chest pain, neck pain, pain radiating to the back and pain on inspiration
How should suspected perforation be investigated?
Erect chest x-ray
Abdominal x-ray showing Rigler’s sign (both sides of the bowl wall visible)
CT scan
How is perforated bowel managed?
IV fluids and antibiotics – ciprofloxacin and metronidazole
Emergency investigative laparotomy
If upper GI perforation, then closure may be an option using stent (oesophageal) or conservatively (peptic) with bowl rest and PPI
If lower GI perforation, then likely a resection will be needed
What is necrotising fasciitis?
Definition – infection of the deep fascia resulting in necrosis of the tissue. Surgical emergency due to its sudden onset and rapid progression. Most commonly it affects the perineum (Fournier’s gangrene).
How is necrotising fasciitis classified?
Classification is based on causative organism
- Type 1 is caused by mixed anaerobes and aerobes (often post-surgery in diabetics) and is most common.
- Type 2 occurs due to streptococcus pyogenes
What are the risk factors for necrotising fasciitis?
Skin – recent trauma, burns or soft tissue infection
Diabetes mellitus (particularly if on SGLT-2 inhibitors)
Intravenous drug use
Immunosuppression
What are the clinical features of necrotising fasciitis?
Acute onset pain, swelling and erythema at sight (rapidly worsening cellulitis with pain out of keeping with physical features)
Extremely tender over infected tissue
Fever
Swelling
Later on: Bullae Dark haematomas Colouration of red to purple to black Gas bubbles in skin Parasthesia
Note immunocompromised patients may not show any signs at all
How should necrotising fasciitis be investigated?
Diagnosis of suspicion
If high suspicion, then small incision made and if the finger easily separates the tissue along the fascial plane then the diagnosis is confirmed.
How is necrotising fasciitis managed?
Sepsis 6 pathway
Surgical debridement
Amputation
Mortality is around 20%
What are fistulas?
Definition – abnormal connection between two epithelial surfaces. The abdominal cavity has the potential for many fistula to form and most arise from diverticula disease and Crohn’s.
What is an enterocutaneous fistula?
This is a connection from intestine to the skin. They can be high output (>500ml) or low output (<250ml) depending on their source. Duodenal/jejunal fistulae tend to produce high volume, electrolyte rich secretion causing skin excoriation. Colo-cutaneous fistula will tend to leak faeculent material.
What is an enteroenteric or enterocoli fistula?
Fistula that involves the large or small intestines and can arise from spontaneous rupture of abscess or with iatrogenic input. These types of fistula bring about serious problems with bacterial overgrowth causing malabsorption problems. Enterovaginal share a similar aetiology.
What is an enterovesicular fistula?
Connection between bowel and bladder. This results in frequent urinary tract infection or the passage of gas from the urethra during urination.
What are the principles of managing a fistula?
- Fistulas will heal provided there is no underlying inflammatory bowel disease or distal obstruction so conservative management is the best option.
- If skin is involved this must be protected as it is difficult to treat so use well-fitting stoma bags
- Octreotide can be used to manage high output fistulas
- Nutritional complications are common especially with high out put fistulas and may necessitate the use of TPN to provide nutritional support along with octreotide and reduce volume and protect the skin
- In perianal fistulas caused by Crohn’s it is often best to drain the acute abscess and maintain drainage through use of setons whilst medical management is implemented.
What is meckel’s diverticulum?
Definition – Congenital abnormality of the small bowl causing a small out pouching from remnant of the vitellointestinal duct (omphalomesenteric duct). The diverticula will contain ectopic ileal, gastric or pancreatic mucosa.
What are the rules of 2 in relation to meckel’s diverticulum?
Rule of 2s: 2% of the population, 2 feet proximal to the Ileocaecal valve, 2 inches in length, 2 years at presentation and 2:1 male: female.
What are the clinical features of meckel’s diverticulum?
Most are symptomless
If there are symptoms this includes
Abdominal pain mimicking appendicitis
Rectal bleeding usually as malaena (most common cause of painless bleeding requiring transfusion between ages of 1 and 2)
This is shortly followed by intestinal obstruction (due to an omphalomesenteric band), volvulus, and intussusception
Can mimic pancreatitis if pancreatic tissue is present
