Acute Abdomen Flashcards
Different characteristics of abdominal pain and what they indicate…
Colicky pain = gall stones, bowel obstruction
Constant, sharp pain worse on movement/ coughing = peritonitis
Constant dull ache = inflammation
Specific signs on examination which reveal pathology…
- Board like rigidity with positive cough test = peritonitis
- Restless patient in pain = colic
- Cullen’s and Grey Turner’s sign = pancreatitis
- Involuntary guarding = peritonitis
- Rebound tenderness= peritonitis
- Loss of hepatic dullness on percussion = pneumoperitoneum
- Tinkling/ high-pitched bowel sounds = bowel obstruction
Where is abdominal pain referred from and to?
Foregut structures (oesophagus to 2nd duodenum, liver, pancreas) = EPIGASTRIC
Midgut structures (2nd duodenum to 2/3 of transverse colon) = UMBILICAL
Hindgut structures =(distal 1/3 of transverse colon to rectum) = SUPRAPUBIC
Initial management of acute abdo pain…
- Analgesia for the pain
- IV fluids
- Keep NBM (in case need for surgery)
Differential diagnosis dependent on location…
Epigastrium:
- MI
- Oesophagitis/ GORD
- Oesophageal rupture
- Peptic ulcer
RUQ:
- Acute cholecystitis
- Ascending cholangitis
- Hepatitis
- Pyelonephritis
- Basal pneumonia
RLQ:
- Appendicitis
- Salpinigits
- Tubo-ovarian abscess
- Ectopic
- Hernial obstruction
- Meckel’s diverticulum
- Crohn’s
- Psoas abscess
LUQ:
- Ruptured spleen
- Gastric ulcer
- AAA
- Pyelonephritis
- Basal pneumonia
- Perforated colon
LLQ:
- Diverticular disease
- Tubo-ovarian abscess
- Salpingitis
- Ectopic
- UC
- Crohn’s
What key diagnoses need to be ruled out?
- Ruptured AAA
- Peritonitis
- Volvulus
- Appendicitis
- Mesenteric ischaemia
- Torsion of structures
What is Meckel’s diverticulum, and what is the rule of 2s?
Congential diverticulum (outpouching) found at the terminal ilieum. Can cause appendicitis-like pain.
Rule of 2s: 2 % of population affected 2 feet from ileocoecal valve 2 inches long 2 year-olds
Pathophysiology of appendicitis…
Appendical lumen is obstructed by lymphoid hyperplasia, faecolith or foreign body.
This obstruction leads to stasis and bacterial overgrowth causing inflammation and distension of the appendix.
How does appendicitis present?
- Initial peri-umbilical pain which migrates to the RIF as the inflamed appendix irritates the peritoneum causing localisation of pain
- Pyrexia
- Vomiting - but not marked
- Loose stools
- Anorexia - loss of appetite
Examination findings in appendicitis…
- Guarding
- Rebound tenderness in RIF
- Rovsing’s sign= tenderness in RIF when pressing on LIF
- Psoas sign = pain on hip extension = retrocaecal appendix (irritating posterior parietal peritoneum)
Investigations for appendicitis…
Bloods:
- FBC - raised WCC in infection
- CRP
- U&E
- LFTs
- Serum B-hCG in young woman
Imaging:
- USS can show inflammation
- CT - rarely used
Management of appendicitis…
- Prompt referral for surgery: laparoscopic/ open appendicectomy
- Broad spec triple antibiotic therapy to be given before surgery:
- Amoxicillin
- Gentamicin
- Metronidazole
Complications of appendicitis…
- Perforation of appendix
- Appendix mass - covered in omentum
- Appendix abscess - requires drainage and appendicectomy
What are the main types of bowel ischaemia?
- Acute mesenteric ischaemia
- Chronic mesenteric ischaemia
- Ischameic colitis
What are the main causes of acute mesenteric ischaemia ?
- Thrombosis or embolus (60-70%) - mainly after vascular event e.g. MI/ stroke, AF
- Non-occlusive (20%) - low flow to the bowel in low output states e.g. cardiac failure or vasopressors e.g. cocaine
- Venous thrombosis (5%) - coagulation disorders, infection
Clinical triad of acute mesenteric ischaemia…
- Severe, acute abdominal pain - disproportionate to clinical signs
- NO clinical signs of peritonitis/ other pathology
- Hypovolaemia/ shock
Investigations for acute mesenteric ischaemia…
Bloods:
- FBC, U&E, CRP, LFT, amylase, clotting
- ABG - metabolic acidosis due to ischaemia
Imaging:
- Plain AXR = gasless abdomen
- Angiography = gold standard
Other:
- ECG - identify precipitating cardiac cause e.g. MI,AF
Management of acute mesenteric ischaemia…
- Fluid resuscitation is important to prevent shock
- Broad spec antibiotics to prevent SBP
- Viable bowel needs thrombolytic infused via catheter
- Emergency surgery - embolectomy/ angioplasty
- All dead bowel must be removed
What are the causes of chronic mesenteric ischaemia?
Atherosclerotic disease of the mesenteric vessels leading to low flow state which causes ‘intestinal angina’.
Vascular risk factors can all contribute to this condition
Clinical triad of chronic mesenteric ischaemia …
- Severe, colicky post-prandial abdominal pain
- Weight loss
- Upper abdominal bruit
Management of chronic mesenteric ischaemia…
*Diagnosed via CT/ MR angiography
Surgery = percutaneous transluminal angioplasty/ stent insertion, bypass
Long term anticoagulation & nitrates given to those not suitable for surgery.
Causes of ischaemic colitis…
Low flow from IMA leads to poor perfusion- mainly affecting splenic flexure
Presentation of ischaemic colitis…
- Large bowel only
- Lower left abdominal pain
- Bloody diarrhoea
- N+V
Investigations for ischaemic colitis…
- Abdominal x-ray: thumb-printing sign due to mucosal oedema
- Lower GI endoscopy = gold standard: Blue, swollen mucosa with contact bleeding
Management of ischaemeic colitis:
- Conservative management for most patients - regaining perfusion with IV fluids
- Surgical management for more severe cases (peritonitis, hypovolaemic shock) - removal of necrotic bowel and stoma formation
What are the two types of bowel obstruction?
Mechanical = bowel has a physical obstruction, peristalsis is still present
Funtional = lack of peristalsis in specific region of the bowel leading to obstruction
Differentiating features of small and large bowel obstruction on imaging…
Small bowel:
- > 3cm dilatation
- Central loops
- Completely traversed by valvulae conniventes
Large bowel:
- > 6m dilatation in bowel, >9 cm dilatation in caecum
- Peripheral loops
- Incompletely traversed by haustra
Differentiating features between small bowel and large bowel obstruction…
Small bowel:
- Pain higher in the abdomen
- Vomiting
- Less distension
Large bowel:
- More constant pain
- Increased distension
What are the main causes of mechanical bowel obstruction?
Intraluminal:
- Foreign body
- Faecal impaction
- Gallstone ileus
Transmural:
- Neoplasm
- Stricture e.g. IBD, diverticular disease
- Fistula
Extramural:
- Neoplasm
- Adhesions e.g. post-op, infection
- Pregnancy
- Hernia
What are the main causes of SBO and LBO?
Small bowel:
- Adhesions
- Hernias
Large bowel:
- Neoplasms
- Strictures
- Faecal impaction
- Sigmoid volvulus
Why are closed loop large bowel obstructions at more risk of perforation?
- Ileocoecal valve remains competent therefore does not allow bowel contents to move back into small bowel
- This causes increasing distension and so greater risk of perforation
What is sigmoid volvulus?
Large bowel obstruction where the sigmoid bowel twists on its mesentery causing rapid, severe, strangulated obstruction.
Risk factors for sigmoid volvulus…
- Elderly
- Chronic constipation
- Parkinson’s disease
Clinical features of sigmoid volvulus…
- Distended abdominal pain
- Absolute constipation
- Vomiting = late sign
Management of sigmoid volvulus …
Rectal tube insertion with rigid sigmoidoscopy to decompress the obstruction
What is paralytic ileus, and what are the causes?
Functional bowel obstruction where there is loss of normal peristalsis in the bowel Causes include: - Abdominal surgery - Peritonitis - Electrolyte abnormalities (K,P, Mg)
Presentation of bowel obstruction…
Symptoms:
- Vomiting
- Colicky abdominal pain - diffuse and central
- Constipation - absolute in large bowel obstruction
Signs:
- Abdominal distension
- PR= faecal impaction
- High pitched tinkling bowel sounds (absent in ileus)
Management of bowel obstruction…
Strangulated and large bowel obstruction = surgery
Small bowel obstruction = drip and suck:
- NG tube to decompress obstruction, then allow drainage
- IV fluids to make up for third space losses of fluid
What is diverticulosis?
Very common disorder where increased intraluminal pressure in the sigmoid colon forces mucosa to herniate through muscle layers outwards - normally between taenia coli.
What is the difference between diverticulosis, diverticular disease and diverticulitis?
Diverticulosis = the umbrella term for the presence of diverticulum:
- Diverticular disease = pathological and symptomatic diverticulum
- Diverticulitis = infection of the diverticulum
Presentation of diverticular disease…
- Altered bowel habits
- L sided colicky abdominal pain - relieved by defecation
- Rectal bleeding
- Constipation
Investigations for diverticular disease…
Bloods: FBC, U&E, LFT, clotting, VBG (lactate for ?infection)
Imaging: colonoscopy, CT, barium enema - all will identify diverticular disease
Management of diverticular disease…
- High fibre diet can help with sx
- Mebeverine can help with pain
- Mild attacks of diverticulitis can be managed with abx
Presentation of diverticulitis…
Acute onset of:
- Severe abdominal pain in LLQ
- Fever
- N+V
- Altered bowel habit
Signs:
- Low grade pyrexia
- Tachycardia
- Tachypnoea
- Guarding in LIF
Investigations for diverticulitis…
Bloods:
- FBC- raised WCC
- CRP raised
Imaging:
- Erect CXR: pneumoperitoneum in perforation
- CT: suspected abscesses
- colonoscopy may cause perforation!
Management of diverticulitis …
Mild attacks:
- Oral abx at home
- Analgesia
- Liquid diet
Sx lasting > 72 hrs:
- Admit to hospital
- IV fluids
- IV abx
- NBM for bowel rest
Complicated diverticulitis= surgery:
- Perforation= Hartmann’s procedure
- Fistulae = colonic resection
- Abscess = drainage
Complications of diverticular disease…
- Perforation –> peritonitis
- Haemorrhage
- Fistula
- Abscess –> swinging fever, leucocytosis
- Post-infective strictures
What is the definition of a hernia?
Protrusion of a viscus through the wall that is containing it
What are the three main risk factors for abdominal wall hernias?
- Anatomical weakness - muscle replaced with scar tissue
- Acquired weakness - trauma, surgery
- Increased intra-abdominal pressure e.g. heavy lifting, straining, obesity
What is an obstructed hernia?
Hernia that protrudes through a wall and is irreducible as it cannot pass back through - may show signs of intestinal obstruction as bowel contents cannot pass.
*At risk of strangulation if blood supply is lost
Features of epigastric hernia..
- Present in midline, along linea alba above umbilicus
- Common in men aged 20-30
What is an incisional hernia?
Occurs at any point of incisional wound after surgery - wound has not healed properly.
Features of umbilical hernia…
- Symmetrical bulge at umbilicus
- Congenital = omphalocele
- Infantile hernias tend to resolve spontaneously
- Adult hernia = pregnancy, obesity, ascites
Why are femoral hernias more common in the elderly…
Protrusion of bowel through the femoral canal.
Develops in the potential space between femoral vein and sheath in the canal.
This potential space becomes bigger with age due to reduced subcutaneous fat
Anatomical location of femoral hernias…
Mass in the upper medial thigh - inferolateral to inguinal hernias.
Tends to point down the leg, unlike inguinal hernias which point to the groin.
Management of femoral hernias…
Surgical management - urgent elective procedure to reduce the hernia.
Anatomical location of inguinal canal…
Internal ring = superior to mid-point of the inguinal ligament (between ASIS and PT) and lateral to epigastric vessels
External ring = superior to PT
What does the inguinal canal contain?
Males =spermatic cord:
- 3 arteries = testicular, artery to vas deferens, cremasteric
- 3 nerves = genital branch of genitofemoral, ilioinguinal, autonomic
- 3 other things: vas deferens, pampiniform plexus, lymphatics
Females = round ligament
Differentiating between indirect and direct inguinal hernias…
Indirect hernia:
- Passes through internal ring and through canal
- LATERAL to epigastric vessels
- Projects through external ring
Direct hernia:
- Protrudes through posterior wall of canal
- MEDIAL to epigastric vessels
- Projects through abdominal wall
Cough test:
- Reduce hernia and cover the deep ring
- Ask patient to cough
- Reappears = direct
- Does not appear = indirect
Management of inguinal hernias…
Hernias with few symptoms = conservative management:
- Weight loss
- Smoking cessation
- Truss belts
Large hernias:
- First time hernia = open inguinal hernia repair - hernia reduced and mesh placed to reduce risk of recurrence
What are complications of mesh repair?
- Urinary retention
- Scrotal haematoma
- Inguinal nerve damage
- Ischaemic orchitis
What are the main risk factors for developing gallstones…
5 Fs:
- Fat
- Female
- Fair
- Fertile
- Forty
Features of biliary colic…
- Colicky abdominal pain present in RUQ caused by gallstones stuck in cystic duct/CBD
- Usually worse post-prandial, especially fatty foods
- Nausea and vomiting
- No fever
Management of biliary colic..
USS shows gallstones = elective laparoscopic cholecystectomy
Pathophysiology of acute cholecystitis…
Stone impaction or sludge impaction within gallbladder leading to build up of stagnant bile fluid - causing increased pressure and risk of infection.
Clinical features of acute cholecystitis…
- Continuous RUQ pain
- Fever
- Murphy’s sign +ve (pt catches breath when inspiring and hand is pressing over gallbladder)
Investigations for acute cholecystitis…
- Raised WCC
- Mildly deranged LFTs
- USS shows thickened wall and shrunken gallbladder , dilated CBD > 6mm
Management of acute cholecystitis…
- Analgesia, IV fluids, IV abx
- Keep NBM and prepare for surgery
- Lap cholecystectomy - ideally within 48 hrs of presentation
Complications of cholecystitis, and their management…
- Gallbladder abscess:
Sx= RUQ pain, swinging pyrexia, unwell
Tx= cholecystectomy or percutaneous drainage - Gallstone ileus:
Sx: known cholecystits, SBO sx e.g. abdo pain, vomiting
Tx= laparoscopy and removal of gallstone but fistula remains in situ - Cholangiocarcinoma:
Longstanding gallstones may cause inflammation and fibrosis of the gallbladder - predisposing to anaplastic changes
Pathophysiology of gallstone ileus…
Gallstones travel from gallbladder through fistula between gallbladder and duodenum, lodging in the ileo-coecal valve.
This may then lead to small bowel obstruction symptoms
Features of obstructive jaundice…
*Post-hepatic cause of jaundice therefore conjugated hyperbilirubinaemia
Symptoms:
- Biliary colic
- Jaundice
- Pale stools, dark urine
Investigations in obstructive jaundice…
- Raised WCC, CRP
- Raised bilirubin
- Raised ALP and GGT
- USS : dilated CBD with stones
Management of obstructive jaundice…
- ERCP
- Cholecystectomy may be required later
Presentation of ascending cholangitis…
Severely unwell patient -septic
Charcot’s triad:
- RUQ pain
- Fever
- Jaundice
Investigations for ascending cholangitis…
- Raised WCC, CRP
- Raised bilirubin
- Raised ALP and GGT
- USS : dilated CBD with stones
Management of ascending cholangitis…
- SEPSIS 6 - if required
- Broad spec abx
- ERCP - early
- Cholecystectomy when patient is well to prevent recurrence
What is an alternative to surgery in gallstone disease?
Dissolve the gallstones by giving ursodeoxycholic acid orally
Pathophysiology of acute pancreatitis…
Inflammation of the pancreas caused by autodigestion from pancreatic enzymes.
Leads to systemic inflammatory response that causes oedema and large fluid shifts –> hypovolaemia.
Causes of acute pancreatitis…
GET SMASHED: Gallstones Ethanol Trauma Steroids Mumps Autoimmune Scorpion venom Hyperlipidaemia ERCP Drugs
Presentation of acute pancreatitis…
Symptoms:
- Sudden onset, sharp stabbing RUQ pain - radiates to the back
- N+V
- Fever
Signs:
- Signs of shock
- Rigid abdomen
- Cullen’s and Grey Turner’s sign (due to retroperitoneal haemorrhage)
Diagnosis of acute pancreatitis…
- Serum amylase (rise 3x upper limit)
- Lipase is more specific and sensitive
- Abdominal x-ray : sentinal loop sign (dilated proximal bowel loop adjacent to pancreas)
- CT for diagnostic uncertainty
What tool is used to assess severity of acute pancreatitis?
Modified Glasgow Criteria - PANCREAS: PaO2 <8kPa Age > 55 Neutrophil - WCC>15 Calcium<2 Renal - urea>16 Enzymes - ALT >200, LDH >600 Albumin <30 Sugar -Glucose >10
Management of acute pancreatitis…
A-E assessment and treatment
- Analgesia
- IV fluids - approx 2L in 2 hrs
- Oxygen
- Enteral feeding - NJ tube to prevent pancreatic stimulation
*Risk stratify patient to see if they need immediate referral to ICU (hypo, AKI, ARDS, hypocalcaemia)
TREAT THE CAUSE!! e.g. ERCP for gallstones
What are the 3 commonest sites that renal calculi will deposit?
- Renal pelvic ureteric junction
- Pelvic brim
- Vesicoureteral junction
Risk factors for renal calculi…
- Middle aged men
- Previous calculi
- Increased calcium
- Increased uric acid e.g. gout
- Dehydration
- Drugs (diuretics, allopurinol, acetazolamide)
Presentation of renal colic…
- Unilateral, sharp colicky pain - ‘loin to groin’
- Fevers and rigors
- N+V
- Haematuria
- Recurrent infections e.g. UTI
Investigations for renal colic…
- Urine dipstick and culture
- Bloods: FBC, CRP, U&E, clotting (if percutaneous intervention required)
- Imaging: CT KUB = 1st line - should be done within 14 hrs
Management of renal calculi …
Acutely unwell patient needs A-E approach:
- Analgesia - diclofenac 75mg IV/IM
- Rehydration - IV fluids
- Antibiotics - tazocin/gent
<5mm - most likely will pass spontaneously:
- Discharge with analgesia (diclofenac is effective), anti-emetics and follow up in O/P
- Patients advised to increase fluid intake and low salt diet
> 5mm/ not resolving:
Medical expulsive therapy:
- Nifedipine/ tamsulosin
Surgical:
- Bladder stone= cystoscopy + extraction
- Ureteric stone <2cm = shockwave lithotripsy
- Staghorn calculi = percutaneous nephrolithotomy
Risk factors for UTI…
- Elderly
- Female
- Indwelling catheter
- Genitourinary tract malformation
- Renal stones
- Diabetes
- High sexual activity
- Incontinence
- Pregnancy
Indicators of an atypical UTI…
- Poor urine flow
- Non responsive to abx in 48 hrs
- Bladder mass
- Raised serum creatinine
Presentation of lower UTI…
Lower UTI = ascending infection moving into bladder and causing inflammation:
- Frequency
- Dysuria
- Urgency
- Nocturia
- Offensive/cloudy urine
- Suprapubic pain
Presentation of upper UTI…
Upper UTI = infection ascending up the ureters into kidneys where it causes inflammation:
- Fever/ rigors
- Loin pain
- Vomiting
- Shock
What is the definition of a complicated UTI?
A UTI which occurs in an individual who already has structural/ functional abnormality in genitourinary tract: obstruction, nephrogenic bladder, catheter
Investigations for UTI…
Urinalysis:
- Dipstick for leucocytes and nitrites
- MSU - send for MC&S
- symptomatic non-pregnant woman can have abx without further investigation
Bloods:
- FBC, CRP, U&E, blood culture, HbA1c
Imaging:
- CT KUB - rule out stones
- Cystoscopy if: male with upper UTI, recurrent, non-responsive to treatment, unusual organism, persistent haematuria
Management of UTI…
Symptomatic non-pregnant woman, with lower UTI: 3 day course of nitrofurantoin/ trimethoprim
Symptomatic non-pregnant woman, with upper UTI: initially treat with broad spec until sensitivity confirmed
Pregnant woman: refer to local guidelines and consult microbiology
Men: 7-day course of nitrofurantoin/ trimethoprim
Catheterised patients: remove and change long term catheter before starting targeted abx therapy from culture sensitivity
Pyelonephritis:
Uncomplicated =ciprofloxacin 500mg BD 1/52
Complicated = admission and broad spec abx
What is the difference between a true aneurysm and a false aneurysm?
True aneurysm = involves all 3 layers of the vessel wall
False aneurysm = pooling of blood between the tunica adventitia and tunica media - lumen still remains unaffected
What are the two types of true aneurysm?
- Saccular: mainly in younger patients and associated with infection
- Fusiform: more common in AAA
Risk factors for AAA…
- Increasing age (reduced elasticity of the walls so increasing pressure will dilate the wall)
- Male
- Hypertension
- Hyperlipidaemia
- Smoking
- Connective tissue disorder e.g. EDS
Definition of an aneurysm…
Abnormal dilatation of a vessel >50% of normal diameter
Presentation of AAA…
Normally asymptomatic!
May cause retroperitoneal pain - loin, back and groin
Presentation of ruptured AAA…
- Intermittent/ continuous abdominal pain (radiate to back, loin and groin)
- Circulatory collapse
- Shock - increased HR and decreased BP
- Expansile pulsatile mass in abdomen
Other complications of AAA…
- Leak: posterior leak is more stable as it is compressed by vertebral column so more time to intervene
- Emboli: may lead to acute limb ischaemia (lower limb)
- Direct pressure effects of AAA on duodenum, ureters, IVC
AAA screening programme
Offered to all men >65 y/o - abdominal USS:
- 3-4.4.cm = annual USS monitoring and encourage healthy lifestyle
- 4.5-5.4cm = 3 monthly monitoring
- > 5.5cm = 2WW to be seen by vascular surgeon
- Growth >1cm/ year = 2WW to be seen by vascular surgeon
Management of AAA…
<5.5cm = Conservative management: Prevention of CVS risk factors: - 80 mg Atorvastatin - Aspirin 100mg + Rivoroxaban 2.5mg - Antihypertensives if required - Smoking cessation - Increased surveillance
> 5.5cm = Definitive management:
EVAR (endovascualr aortic repair) : stents inserted via both femoral arteries into aorta
Open laparotomy: aneurysm sac opened and graft inserted and sutured into place
What are the disadvantages of EVAR?
- Stent may move position and aneurysm may no longer be contained
- Continued surveillance required
- May be less appropriate for young people due to lifetime risk of complications
Why are patients allowed appropriate hypotension in ruptured AAA?
Most ruptured AAA = retroperitoneal (80%) - the aneurysm is contained due to retroperitoneal haematoma that forms.
If BP gets too high (>100mmHg) then it may cause removal of the haematoma and effectively remove the plug from the ruptured aneurysm.
Management of ruptured AAA…
A-E management is important:
- Wide bore IV access - IV fluid resuscitation
- Urgent X-match 4 units - use O-ve whilst waiting
- Ix= Hb, ECG
- Emergency open repair - clamping above leak and graft insertion
*Unstable patients do not need CT scan - but if stable it can help plan procedure
Why is GA not given until patient is on the table with surgeon ready to start?
Tension of the abdominal wall acts as a natural tamponade to the bleed so as soon as GA is given it will relax the muscle so surgery must begin immediately.
