Organ Failure Past Paper PDF

Organ Failure masterdoc 1. Which of the following does NOT cause intrinsic renal failure? a. b. c. d. e. Penicillin WRONG. This causes acute interstitial nephritis, part of intrinsic renal failure. Myoglobin WRONG. This causes rhabdomyolysis, which causes acute tubular necrosis. Hartmann’s solution...

Organ Failure masterdoc 1. Which of the following does NOT cause intrinsic renal failure? a. b. c. d. e. Penicillin WRONG. This causes acute interstitial nephritis, part of intrinsic renal failure. Myoglobin WRONG. This causes rhabdomyolysis, which causes acute tubular necrosis. Hartmann’s solution CORRECT. This is a resuscitation fluid used to treat renal failure. Radiocontrast media WRONG. This causes acute tubular necrosis, part of intrinsic renal failure. Gentamycin WRONG. This causes acute tubular necrosis, part of intrinsic renal failure. 2. Which of the following is true regarding the functional histology of the kidney? a. Podocytes line the PCT & DCT WRONG. Podocytes line the Bowman’s capsule. PCT & DCT have simple cuboidal epithelium instead. b. Tight junctions line the thin limb of the Loop of Henle WRONG. They line the thick limb. c. Ion pumps line thick limb of the Loop of Henle CORRECT. This is where most of the ion active transport happens. It is not permeable to water ie there are tight junctions here. 3. Which of the following statements about the treatment of paracetamol hepatoxicity is most appropriate? a. NAC – metabolised to intracellular gluathathione CORRECT. N-acetylcysteine (NAC) is a precursor for glutathione, which will neutralize NAPQI (paracetamol’s hepatotoxic metabolite) 4. Which of the following statements about comatose is most appropriate? a. b. Capable of voluntary movement WRONG. Duh… Bilateral damage to reticular formation CORRECT. This can lead to coma or death. 5. Extradural Haemorrhage… a. b. c. d. e. Requires surgical evacuation CORRECT. Is caused by venous bleed WRONG. It’s usually arterial bleeds (hence why so dangerous – high pressure). Is between dura & arachnoid WRONG. This is subdural haemorrhage. Extradural is between dura and skull. Is common in elderly WRONG. Not exactly wrong but it’s not particularly common in elderly. Is caused by ruptured aneurysm WRONG. It’s usually due to trauma, rather than ruptured aneurysm. 6. Which of the following statements about renal replacement therapy is most appropriate? a. Hyperkalaemia is an indication CORRECT. Other indications are refractory volume overload, metabolic acidosis, or uremic symptoms (eg pericarditis, neuropathy). b. Intermittent haemodialysis is the preferred choice in unstable patients WRONG. 7. Which of the following statements about drug-metabolising enzymes is most appropriate? a. b. c. d. e. Found only in liver WRONG. Mainly in liver, but also in small intestine epithelium, kidney, lung, skin. Detoxify environmental toxin and drugs CORRECT. High substrate specificity WRONG. They usually have broad specificity. Make more hydrophobic WRONG. Metabolites are less lipophilic (ie more hydrophilic). Always breakdown to inactive substrates WRONG. Substrates can be inactive, active or toxic. 8. Respiratory control a. b. c. d. Pons WRONG. Respiratory centre is in pons AND medulla. Control is also affected by peripheral receptors. CO on peripheral chemoreceptors WRONG. CO2 levels are measured by PCs using H+, not CO2 itself. pCO2 inversely related to minute ventilation CORRECT. The larger you minute volume, the less your pCO2. pO2 has no effect on minute ventilation WRONG. It does have an effect. 2 9. Which of the following can lead to type 2 respiratory failure? a. b. c. d. e. Pulmonary embolism WRONG. This can lead to both types but E is most specific. Pneumonia WRONG. This leads to Type I instead. ARDS WRONG. Same as B. Asthma WRONG. This can lead to both types but E is most specific. Head injury CORRECT. Head injury leads to respiratory centre depression, which leads to Type II. 10. Renal hypervolemia is cured by… a. Increase sodium reabsorption WRONG. This increases water reabsorption, making hypervolemia worse. b. Increase GFR WRONG. It’s the reabsorption rate not GFR that needs to rectified. c. Increase afferent arteriole vasodilation. WRONG. This only serves to increase GFR. See B. d. Decrease water reabsorption CORRECT. e. Decrease EPO production WRONG. EPO is made in renal cortex but its main role is control of RBC production. 11. Which of the following is NOT a sign of left heart failure? a. b. c. d. e. Elevated JVP CORRECT. This is a sign of right heart failure instead. Orthopnea WRONG. LHF exerts back-pressure on pulmonary veins, which subsequently causes this. Pleural effusion WRONG. Same as B. Shortness of breath WRONG. Same as B. Paroxysmal nocturnal dyspnoea. WRONG Same as B. 12. Which of the following statements about the RAAS is most appropriate? a. b. c. d. e. ACE is produced in respiratory epithelial cells WRONG. ACE is produced in respiratory endothelial cells. AGII increases Na reabsorption in the proximal convoluted tubule CORRECT. Renin is a potent vasoconstrictor WRONG. Renin converts AG into AGI, which ACE turns into AGII. See E. Renin production is primarily in the macula densa WRONG. It’s produced in the granular cells of JGA. AGII promotes vasodilation. WRONG. AGII is a vasoconstrictor. 13. Brainstem death diagnosis if… a. b. c. d. e. Systemic exam of cranial nerves CORRECT. GCS Score of 3 WRONG. GCS doesn’t measure everything eg brainstem reflexes, breathing. Involuntary movements are seen WRONG. MRI WRONG. Upper cortical activity may be present WRONG. If this happened the brainstem is definitely not lesioned. 14. Which of the following statements about aldosterone is most appropriate? a. It increases Na and H2O reabsorption in the distal nephron WRONG. Technically it increases Na reabsorption and water just follows suit. b. It is stored in the posterior pituitary WRONG. It’s produced in adrenal cortex zona glomerulosa. It’s ADH that is stored in the posterior pituitary. c. It stimulates vasoconstriction WRONG. It’s AGII that stimulate vasoconstriction. d. It increases plasma osmolality WRONG. It decreases plasma osmolality. e. A deficit leads to hyperkalemia CORRECT. 15. Which of the following statements about airway resistance is most appropriate? a. b. c. d. e. β1 agonists reduce airway resistance WRONG. β2 agonists stimulate bronchodilation, thus reduce resistance Small airways are a major site of airway resistance WRONG. The larger the airway, the more resistance. Airway resistance is typically lower in infants and children. WRONG. It’s higher in kids than in adults. Airway resistance is low in asthma WRONG. It’s high in asthma due to airway obstruction. Air flow is laminar as long as Reynold’s number < 2300. CORRECT. >2300, it may become turbulent. 16. A 23-year-old male presents with BP 90/50, heart rate 125 and Hgb 6g/dl. He was involved in a car crash where both his femurs broke. Which of the following measures is most appropriate? a. He should see an orthopaedic surgeon first WRONG. The broken bones are not the first priority. See B. b. He should be given IV fluids CORRECT. The haemorrhage plus low Hb means there is very low circulating volume and thus oxygen delivery. This is the first thing that needs to be addressed. c. It is advisable to wait for blood due to his low haemoglobin WRONG. See B. d. Blood pressure is not a priority WRONG. He is quite hypotensive and is entering hypovolemic shock. See B. 17. Which of the following statements about respiratory shunt is most appropriate? a. b. Shunt is perfusion without ventilation CORRECT. Shunt is ventilation without perfusion WRONG. This is dead space. 18. Which of the following statements about heart failure is most appropriate? a. b. c. d. e. Paroxysmal nocturnal dyspnoea is a good indicator CORRECT. PND is quite specific to chronic heart failure. It is always systolic WRONG. It can be systolic, diastolic or both. It is associated with low blood pressure WRONG. It’s associated with high BP. JVP can be seen most clearly when patient is supine WRONG. It’s seen best when patients sits leaning back. IHD is an uncommon cause WRONG. It causes the majority of systolic heart failure. 19. Cardiogenic shock a. Dobutamine can be useful CORRECT. This is a β1 agonist. 20. Pre-renal failure is best treated using which of the following treatments? a. a. a. a. b. Isotonic IV fluid CORRECT. This will counter the hypoperfusion that causes pre-renal failure. IV dextrose WRONG. This is used to treat hypoglycaemia(that can lead to coma) IV dopamine WRONG. Low-dose dopamine does promote renal vasodilation, but evidence is very poor. Feoladapam WRONG. This doesn’t seem to exist… NAC WRONG. This is to treat paracetamol hepatotoxicity as it neutralizes NAPQI. 21. Which of the following statements about cardiac contractility is most appropriate? a. ATP is necessary for relaxation CORRECT. ATP binding to the myosin head allows it to detach from the actin filament, thus allow the muscle to relax. b. Ca concentration is highest in the extracellular space c. Ca binds to tropmyosin WRONG. Ca binds to troponin, which moves tropomyosin away for myosin to bind to d. Digoxin reduces intracellular Ca WRONG. Digoxin increases intracellular Ca. actin. 22. In relation to cerebral blood flow, electrical activity in the brain is lost at… a. b. c.