Acute Abdomen Flashcards
Differentials for epigastric pain?
Intrathoracic: myocardial infarction, pericarditis, pleurisy, basal pneumonia, PE,
oesophagitis, oesophageal perforation
- Upper GI: peptic ulcer, GORD, pancreatitis
Differrentials for upper quadrant pain?
Intrathoracic: myocardial infarction, pericarditis, pleurisy, basal pneumonia, PE
- Kidney: pyelonephritis, renal stones
- On the right, symptoms can be due to the liver or biliary tree: gallstone complications,
hepatitis, liver abscess/cyst, hepatic congestion
- On the left, symptoms can be due to the spleen: rupture, abscess, acute splenomegaly
Differentials for lower quadrant and central pain?
Bowel: mesenteric adenitis (viral lymphadenopathy of the mesentry), diverticulitis,
obstruction, hernia complications, perforation, colitis (IBD, ischaemia, pseudomembranous)
- Gynaecological: mittelschmerz, salpingitis, tubo-ovarian abscess, ruptured ectopic
pregnancy, ovarian torsion, PID, endometriosis
- Kidney: pyelonephritis, renal stones
- Musculoskeletal: psoas abscess
- On the right, symptoms can be due to: appendicitis, Meckel’s diverticulitis
Vascular causes of an acute abdomen?
AAA, Mesenteric Iscaemia
Medical causes of abdominal pain?
DKA, Septicaemia, shingles, sickle cell crisis and infection
Most severe causes of acute abdomen?
Haemorrhage Peritonitis Closed loop obstruction inflammation open loop intestinal obstruction
How long should they be NBM?
6 hours food 2 hours clear fluids
Why does appendicitis happen? When is it most common?
btw ages of 10-20. Gut organisms invade the wall of the appendx after luminal obstruction. Then get oedema and ischaemic necrosis, Lumen can be obstructed by faecolith, worms or lymphoid hyperplasia.
How will appendicitis present?
Colicky, periumbilical pain until it localises to the RIF when peritoneum becomes inflamed.
- McBurney’s point: 2/3rd of the way from the umbilicus to ASIS
Also tachycardia, fever, anorexia, constipation, and (in some cases, after pain onset)
vomiting
What signs may you find on examination of appendicitis?
Tender in the RIF and there is potentially rebound tenderness/
guarding
Rovsing’s sign may be present, where pressing on the LIF elicits pain in the RIF
There can also be psoas sign (pain on hip extension) and Cope sign (pain on flexion and
internal rotation of the hip)
What ix should you do in appendicitis?
- Urine dip incl BHCG in women and routine blood tests, will show a neutrophillia and raised CRP
Ultrasound is useful, CT is rarely used due to delaying treatment but has high diagnositic accuracy if uncertain
What scoring system is used in appendicitis?
Alvorado scoring system Out of 10: <4- unlikely 5-6 ? CT 7+ operate
Looks at clinical and Lab criteria Pain migration 1 Anorexia 1 Nausea/ Vomiting 1 RLQ Tenderness 2
Rebound Tenderness 1
Temp >37 1
Neutrophils >75% 1
WCC >10 2
What treatment is used in appendicitis?
Treatment is prompt appendicectomy, which can be laporoscopic or open
- Open appendicectomy can be Gridiron or Lanz. The Lanz incision is lower and more
horizontal) - IV antibiotics are important, usually metronidazole and cefuroxime. These should be given
prior to surgery
Where does visceral pain refer to?
Foregut (oesophagus to 2nd duodenum, liver, pancreas) is epigastric
- Midgut (2nd duodenum to 2/3rd transverse colon) is umbilical
- Hindgut (2/3rd transverse colon to rectum) is suprapubic
What are the complications of appendicitis?
perforation
appendix mass (inflamed appendix covered with omentum) (conservative then later appendicectomy)
appendix abscess (where an appendix mass is left unresolved)- will require percutaneous drainage and abx with later appindecectomy
What is Merckels diverticulum?
congenital vestigial remnant of the vitellointestinal duct in the
distal ileum containing gastric mucosa
(rule of 2s)
Complications will occure in around 2%
What are the complications of meckels diverticulum?
Intestinal obstruction, this may be due to intussusception or volvulus
- Diverticulitis
- Perforation
- Neoplasia
- Haemorrhage, typically painless fresh PR bleeding in a child <2
(if occur, resect)
What is the blood supply of the digestive system?
branches of the abdominal aorta,
The foregut is supplied by the celiac trunk
The midgut is supplied by the branches of the superior mesenteric artery
The hindgut is supplied by the branches of the inferior mesenteric artery
What is acute mesenteric ischaemia?
umbrella term for impaired blood flow to the intestine wit bacterial relocation to normally sterile tissue and SIRS
Causes of acute mesenteric ischaemia?
Mesenteric arterial embolus and thrombus
o Mural thrombus following MI, septic emboli from IE, AF
- Mesenteric venous thrombus
o Hypercoagulability disorders, tumours causing venous compression, infection,
venous trauma - Non-occlusive mesenteric ischaemia
o Hypotension, vasopressive drugs (including cocaine)
How do patients with acute mesenteric ischaemia present?
Patients usually present with moderate-to-severe colicky pain that is poorly localised
- Physical findings are out of proportion to the degree of pain, and there may be no features
of tenderness or peritonitis - Hypovolaemia and shock occur rapidly
What ix are important in acute mesenteric ischaemia ? (initial and further)
A to E assess and stabilise the patient
- Give high flow oxygen through a non-rebreathe mask, the patient will be breathless due to
lactic acidosis (perform ABG)
- Gain IV access and commence fluid resuscitation
o Bloods to include FBC, U&Es, LFTs, coagulation profile, and G&S
o ECG
Plain AXR and erect CXR can be used to exclude differentials, AXR may show thumb-printing
- Abdominal CT can show some features
- Angiography is the gold standard for diagnosis
- Echocardiogram can show valvular pathology leading to embolism
Management of acute mesenteric ischaemia?
- Initial resus with fluids and oxygen as A to E
- Also ABX such as ceftriaxone or anything with enteric cover as bacteria can translocate
-If no evidence of perf, can use thrombolytics down the angiogram catheter eg papaverine (or heparin in MVT)
Surgery may be required such as embolectomy, angioplasty or laparotomy and resection of any dead bowel.
What is chronic mesenteric ischameia?
occurs when there is atherosclerotic disease affecting the vessels that supply the intestine
How does chronic mesenteric ischaemia present?
postprandial colicky pain due to claudication, this often leads to weight loss as eating is uncomfortable
- Chronic mesenteric ischaemia is often called intestinal angina for this reason
- Patients will also often have associated vascular disease e.g. TIA, angina
On examination patients may have an upper abdominal bruit
What ix should be donw in chronic mesenteric ischaemia?
Routine bloods and ECG should be carried out to assess CVD risk factors and exclude malnutrition
Diagnostic investigation is imaging
- Angiography is gold standard
Management of chronic mesenteric ischaemia?
MEdical: limited, only in pts not suitable for surgery and is usually with nitrates
Surgical: Transaortic endarterectomy of coeliac os SMA, bypass grafting or angiography and stenting
What is Ischaemic colitis and what causes it?
Caused by compromise of the blood supply to the colon, commonly affecting the splenic flexure
The most common cause is atheroma of the mesenteric arteries
- Certain factors can predispose to ischaemic colitis, these factors are similar to mesenteric ischaemia
HOw does ischaemic colitis present?
with acute onset abdominal pain, usually in the LIF
- There is often nausea, vomiting, and loose stools containing dark or fresh blood
Ix in ischaemic colitis?
loods should be the same as in mesenteric ischaemia. Following this there can be further imaging
- Erect CXR and AXR
- CT can indicate likely ischaemic colitis, further to this there can be either
o Colonoscopy can show blue, swollen mucosa with contact bleeding
o Barium enema shows thumb-printing with a similar appearance to UC and Crohn’s
Management of ichaemic colitis?
Bowel ischaemia often resolves once the cause of hypoperfusion has been alleviated, therefore it is important to give IV fluids and rest the bowel
- Surgery is rarely required, and used to correct perforation, necrosis and strictures
How can bowel obstruction be divided?
Static and dynamic causes. Dynamic is mechanical, static is a failure of peristalsis eg ileus
How can you distinguish btw small and large bowel on xray?
Small bowel obstruction can be identified by multiple dilated (>3cm) loops of central bowel, completely traversed by valvulae conniventis
- Large bowel obstruction can be identified by dilated (>6cm or >9cm at the caecum) loops of peripheral bowel, incompletely traversed by haustra
What are the cases of mechanical bowel obstruction?
Intraluminal
Foreign body
Faecal impaction
Gallstone
Transmural
Neoplasm
Stricture (e.g. Crohn’s disease, radiotherapy, diverticular disease, post-operative)
Fistula
Extraluminal
Adhesion (post-operative, infection, inflammation, congenital) Neoplasm Pregnancy Volvulus hernia
COmmonest causes of small bowel obstruction?
Adhesions
- Hernias
- Other causes e.g. foreign bodies, tumours (most commonly benign polyps), strictures, gallstone ileus
COmmonest causes of large bowel obstruction?
Neoplasm (usually primary malignancy)
- Structures (usually diverticular)
- Faecal impaction
- Sigmoid or caecal volvulus
o Volvulus is rotation of the gut on its mesenteric axis, more commonly sigmoid
o This can produce a severe, rapid, strangulated obstruction
What is a closed loop obstruction?
ileo-caecal valve remains competent, therefore there can be no decompression of bowel contents into the small bowel. This is much more dangerous, and likely to perforate
Perforation occurs due to increasing pressure leading to decreased venous return, oedema, and decreased arterial supply. This causes necrosis of the bowel wall
- Another effect of decreased venous return and oedema is bacterial translocation, risking peritonitis in the absence of perforation
WHat are the causes of paralytic ileus?
Post-operative
- Peritonitis or viscus perforation
- Trauma
- Metabolic and electrolyte disturbances e.g. uraemia, hypokalaemia
- Other acute abnormalities e.g. chest infection, MI, stroke, AKI, DKA, hypothyroidism, pancreatitis
How will intestinal obstruction present?
There are four cardinal features of intestinal obstruction.
1. Vomiting, which may be faeculant
2. Colicky pain, this is usually diffuse and central. In paralytic ileus, pain is absent
3. Complete constipation i.e. no flatus or faeces
4. Distension
On examination there may be tenderness, highly active ‘tinkling’ bowel sounds on auscultation and hyper-resonant percussion. It is important to check for hernias
Severe pain and tenderness suggests ischaemia or perforation
What ix should be done in bowel obstruction?
Therefore fluid charts are essential to monitor intake and output, and catheterisation may be needed for an accurate calculation of requirements (lots of third space losses)
Routine bloods : clotting, group and save, and cross match as surgery may be required
- AXR, looking for air-fluid levels and distention (>3cm in small bowel, >6cm in large bowel, and >9cm in the caecum)
- Erect CXR where perforation is suspected
- CT scanning can be used where there is diagnostic uncertainty
Management of Bowel Obstruction?
keep patients NBM and ensure they are catheterised
Drip and suck
NG tube -decompresses the bowel and reduces the risk of perforation, but also alleviates vomiting
- After initial NG placement there should be aspiration of fluid, and then the tube should be left on free drainage
How is volvulus managed?
Conservative passage of a flatus tube
When is surgery indicated in bowel obstruction?
strangulation, perforation, or closed-loop large bowel obstruction. For other cases, usually conservative measures will be trialled for 24 – 48 hours before consideration of surgery to alleviate the obstruction
What can be done in bowel obstruction for pts not suitable for surgery?
Endoscopic stenting
