Acute Abdo Flashcards
What are the causes of abdominal perforation?
Stomach or duodenal ulcer Malignancy Fistula - crohns Infection - appendicitis, diverticulitis Ischaemia Obstruction Iatrogenic - anastomotic leak, endoscopy Trauma Direct - excessive vomiting
Name 2 signs on an X-Ray of perforation.
Rigler’s sign
Psoas sign
How might a retroperioneal perforation present?
R shoulder tip pain
Back pain
RIF pain - contents settles in paracolic gutter
What are the complications of perforation?
Infection - peritonitis + sepsis
Haemorrhage
What are signs of localised peritonitis?
Tender on palpation
Guarding
Rebound tenderness
May have systemic signs of infection
What are causes of localised peritonitis?
Appendicitis, Crohn’s disease, diverticulitis
Cholecystitis, salpingitis
What are signs of generalised peritonitis?
Abdomen rigid and tender
Cough test +ve
Bowel sends absent - peristalsis stopped
What causes generalised peritonitis?
Perforation of a viscus
What are the 2 types of generalised peritonitis?
Chemical - bile, stomach or small bowel contents
Bacterial - abscess rupture or faecal contamination from bowel, trauma, surgery or post-surgical leak
What is the management of generalised peritonitis?
High dose IV Abx
Urgent laparotomy to find cause and clear material ‘peritoneal toilet’
Describe the pathophysiology of pancreatitis.
Inflammation of pancreas.
Vascular permeability and fluid loss (3rd spacing)
Enzyme activation - tryptase
Fat necrosis by lipase, free FA react with calcium to form deposits (hypocalcaemia)
Enzymes can erode blood vessels -retroperitoneal bleeding
What are the causes of pancreatitis?
Iatrogenic/idiopathic Gallstones Ethanol Trauma Steroids Mumps Autoimmune - SLE Scorpion/snake bite Hypercalcaemia, hyperlipidaemia, hypothermia ERCP Drugs
Which drugs can cause pancreatitis?
Steroids
Azathioprine, antibiotics
NSAIDs
Diuretics
How does pancreatitis present?
Sudden onset severe, constant upper abdo pain. Radiates to back. Relieved sitting forward Vomiting Abdo distension
What are differential diagnosis for upper abdo pain radiating to the back?
Radiating to back:pancreatitis, ruptured AAA, dissecting aorta
Epigastric: peptic ulcer
Biliary colic cholecystitis
Pneumonia, Inferior MI
What investigations would you do in a patient with suspected pancreatitis?
FBC, U&E, CRP Amylase LFTs Lipase (if trust allows) ABG USS (unless obv cause)
What is important to remember about amylase?
- Levels do not correlate with disease severity
- Falls 24-48 hrs
Other than pancreatitis, what else can cause amylase to be raised?
Bowel perforation
Ectopic pregnancy
Mesenteric ischaemia
DKA
When should a CT scan be ordered in a patient with pancreatitis?
Only if not improved after 6-10 days and suspect complications such as necrosis.
If gallstone is found to be the cause of pancreatitis, what management should happen?
ERP and sphincterotomy within 72 hours.
What scale is used to grade the severity of pancreatitis?
Glasgow scale
Outline the glasgow scale.
PaO2 < 8kPa Age > 55 Neutrophilia > 15x10^9 Calcium < 2 mmol/L Renal, urea >16 mmol/L Enzymes, LDH > 600, AST > 200 Albumin < 32 g/L Sugar - blood glucose > 10 mmol/L
3 or more = severe, ICU for monitoring
Why is ABG and acid-base status important in pancreatitis?
ARDs is an early complication
Metabolic acidosis is complication associated with poorer prognosis
List systemic complications of pancreatitis.
DIC Renal failure Sepsis ARDS Hypocalcaemia Hyperglycaemia Hypovolaemic shock and MOD
List local complications of pancreatitis.
Pancreatic necrosis - prone to infection Fluid collection Pancreatic psueudocyst Pancreatic abscess Haemorrhage
What are causes of RIF pain in both males and females?
Appendicitis Constipation Strangulated hernia Perforated caecum IBD - Crohn's disease Renal colic Mesenteric adenitis (child) UTI Meckel's diverticulitis
What are additional causes of RIF pain in females?
Ruptured ectopic pregnancy Tubo-ovarian abscess Salpingitis/PID Mittelschmerz UTI more likely
What investigations should you do for a patient with RIF pain?
Urine dip - UTI
Preg test if F
Bloods - FBC, U&E, CRP, amylase
What imaging could you do in suspected appendicitis?
USS - will show mass or abscess
CT - accurate
What is the cause of appendicitis?
Gut organisms (E.Coli) invade lumen following blockage by hyperplasia of lymphoid tissue or faecolith. Mucosa inflammation, then extends through wall to serosa.
What are 5 positions of the appendix?
Retrocaecal Subcaecal Pelvic Pre-ileal Post-ileal
What sign can you use to diagnose appendicitis in a retrocaecal appendix
Psoas sign - extension of hip causes pain as appendix irritates the psoas muscle
How can appendicitis result in diarrhoea or urinary symptoms?
Pelvic appendix can irritate rectum or ureter
What abdominal sign can be used to help diagnose appendicitis?
Rosvings sign - pain greater in RIF than the LIF when the LIF is pressed.
What complications are associated with appendicitis?
From op: ileum, infection from wound or intra-abdominal, adhesions/obstruction, incisional hernia.
Perforation
Appendix mass
Appendix abscess
Outline the pathophysiology following bowel obstruction.
Once occluded, dilatation of proximal bowel and increased peristalsis (to begin with). This leads to large volumes of fluid secretion ‘third spacing’.
How does bowel obstruction present?
Abdo pain Nausea + vomiting Constipation - absolute Abdo distension Anorexia
How can small and large bowel differ in their presentation?
Small - vomiting first, then constipation
Large - constipation first, may not vomit, more distension as proximal bowel fills
How is the abdo pain associated with bowel obstruction described?
Often colicky or crampy to begin with (due to peristalsis), then becomes constant
What are the 2 types of bowel obstruction according to their mechanism?
Simple - one obstructed point with no vascular compromise
Closed loop - two obstructed points with a loop at risk of ischaemia and perforation e.g. sigmoid volvulus
What are common causes of small bowel obstruction?
Adhesions
Hernias
What are common causes of large bowel obstruction?
Colon Ca
Volvulus
Constipation
Diverticular disease
What are rarer causes of bowel obstruction?
Gallstone ileus
Crohns stricture
TB
Foreign body
How is sigmoid volvulus managed?
Insertion of flatus tube or sigmoidoscopy
What signs might indicate that obstruction is associated with ischaemia?
Peritonitic signs - rebound tenderness, guarding, no bowel sounds.
What investigations should you do in a pt with suspected bowel obstruction?
FBC, U&E, CRP
Group & Save
Venous blood gas - signs of ischaemia (lactate) or metabolic alkalosis from vomiting
AXR
What are the diameter for small bowel, large bowel and sigmoid/caecum obstruction?
> 3cm
6cm
9cm
What is a classic sign of sigmoid volvulus on AXR?
coffee bean sign
What is the conservative management for bowel obstruction?
‘Drip and suck’
- NBM and insert NG tube to decompress bowel
- IV fluids and electrolyte correction
- Analgesia and antiemetics
When is surgical intervention rather than drip and suck indicated for bowel obstruction?
- Suspected ischaemia or closed loop
- Small bowel obstruction in virgin abdomen
- Cause needs correction - strangulated hernia or tumour
- Conservative for 48 hours not relieved
What are complications of bowel obstruction?
Bowel ischaemia
Perforation and faecal peritonitis
Dehydration and renal impairment
What 2 pieces of information do you need before CT?
Renal function - creatinine
Allergies to contrast
Other than obstruction, what is another important differential causing abdo distension?
Ascites
Why is a CT a useful investigation following AXR for bowel obstruction?
Can confirm dilatation of bowel
Point of obstruction
Evidence of metastatic disease cause
