CST Interview - Clinical Scenarios Flashcards
(114 cards)
Differential diagnosis for post-op (GI surgery) abdominal pain in unwell patient?
Anastamotic leak with peritonitis, septic shock, haemorrhagic shock, bowel perforation, ischaemic bowel, obstruction, wound infection, sepsis
Why can unwell patients with IBD be difficult to assess in terms of haemodynamics and clinical signs?
They tend to be immunosuppressed which can mask signs of peritonism. Also tend to be young with large physiological reserve
What is a stoma?
A therapeutic opening in the wall of a hollow viscus
How can you differentiate an ileostomy from a colostomy? 2 ways
An ileostomy has a spout vs colostomy flush to skin. Contents usually greenish, loose (small bowel content)
Types of ileostomy? 2
End ileostomy - single barrelled with 1 lumen
Loop ileostomy - double barrelled with proximal and distal lumen
What is the purpose of a loop ileostomy?
Divert enteral contents away from area of bowel that is e.g. healing or obstructed. Ex. j pouch in subtotal colectomy with ileorectal anastamosis
Which parts of the colon can be mobilised and therefore are suitable for loop colostomy formation?
Transverse and sigmoid
Differences between Crohns and UC? 3 differences
Crohns has full thickness skip lesions on histology, cobblestoning on endoscopy and can involve any part of GI tract. UC has continuous superficial ulceration usually in rectum and colon
Risk of multiple bowel resections for Crohns? Symptoms?
Short bowel syndrome - malabsorption of vitamins + minerals. Can be temporary. Diarrhoea + weight loss, malnutrition
At what level of small bowel loss does short bowel syndrome usually occur?
When there is <2m left of 6.1m short bowel left
Risk factors for anastamotic leaks? Split into 3 groups
Patient (smoker, diabetes, PVD, steroid use, malnutrition/anaemia). Pathology (IBD, collagen disorders, autoimmune disease). Procedural (tension across anastamosis, local infection, inadequate blood supply to cut ends, location low rectal more than right colon more than small bowel)
What are POSSUM and P-POSSUM? Stand for and use?
Validated scoring systems used to inform on risk of operative intervention by giving 30 day morbidity + mortality estimates. Stand for Physioloical and Operative Severity Score for the enUmeration of Mortality and Morbidity, (Portsmouth). 12 physiological and 6 operative variables.
Other than emergency, how can anastamotic leak presesnt post op?
Indolently with prolonged ileus, vague abdo pain, low grade temp + tachy.
Management of localised minor anastamotic leak?
NG tube + bowel rest, CT and/or water soluble enema. Antibiotics and drainage of collections
Cause of acidosis + deranged LFTs in patient post-op from liver resection?
Portal vein thrombosis
Management of basal atelectasis? Role of antibiotics?
Oxygen titrated to saturations, chest physiotherapy, coughing/deep breathing. Antibiotics only indicated if signs and symptoms present; not prophylactically although patients are at higher risk
General factors implicated in development of post-op atelectasis?
General anaesthesia (surfactant dysfunction, poor ventilation of basal alveoli), post-op immobility (poor ventilation)
Specific incision-related contributing factor to post-op atelectasis?
Large incisions e.g. subcostal discourage deep breathing
4 causes of post-op hyponatraemia?
Post-op SIADH, inappropriate crystalloid administration, drugs, post-op ileus
Causes of rising PT in post-op liver resection patient?
Vit K deficiency OR synthetic liver dysfunction e.g. post-hepatectomy liver failure or small-for-size syndrome
Stages of haemorrhagic shock in relation to blood loss and clinical sking/symptoms?
Stage 1 - less 15%, normal
Stage 2 - 15-30%, tachy, narrow pulse pressure
Stage 3 - 30-40%, tachy, hypotensive
Stage 4 - more 40% (2000ml), anuric, hypotensive
Management of hyperkalaemia?
Calcium gluconate 10mls 10%
Insulin dextrose 10 units 50mls 50%
Neb salbutamol
Serial measurements + cardiac monitoring
4 indications for dialysis in AKI?
Refractory hyperkalaemia
Refractory pulm oedema/overload
Severe metabolic acidosis
Uraemic encephalopathy/pericarditis
Difference between haemofiltration and haemodialysis?
Haemofiltration uses pressure of fluid across semipermeable membrane, hydrostatic pressure driving molecules into ultrafiltrate which is discarded + replaced. Haemodialysis used diffusion of molecules across membrane using dialysing fluid