PHYSIO 2 Flashcards
What is the approximate volume of pancreatic secretions in a 24 hour period?
100ml 200ml 500ml 1500ml 3000ml
1500ml
Typically the pancreas secretes between 1000 and 1500ml per day
A 34 year old lady has just undergone a parathyroidectomy for primary hyperparathyroidism. The operation is difficult and all 4 glands were explored. The wound was clean and dry at the conclusion of the procedure and a suction drain inserted. On the ward she becomes irritable and develops stridor. On examination, her neck is soft and the drain empty. Which of the following treatments should be tried initially?
Administration of intravenous calcium gluconate Administration of intravenous lorazepam Removal of the skin closure on the ward Direct laryngoscopy Administration of calcichew D3 orally
Administration of intravenous calcium gluconate
Exploration of the parathyroid glands may result in impairment of the blood supply. Serum PTH levels can fall quickly and features of hypocalcaemia may ensue, these include neuromuscular irritability and laryngospasm. Prompt administration of intravenous calcium gluconate can be lifesaving. The absence of any neck swelling and no blood in the drain would go against a contained haematoma in the neck (which should be managed by removal of skin closure).
A 44 year old lady presents with jaundice. Following a minor ward based surgical procedure she develops troublesome and persistent bleeding. Deficiency of which of the vitamins listed below is responsible?
Vitamin C Vitamin K Vitamin D Vitamin B Vitamin A
Vitamin K
Patients who are jaundiced usually have impaired absorption of vitamin K. This can result in loss of the vitamin K dependent clotting factors and troublesome bleeding.
A 23 year old man presents with blunt abdominal trauma and a splenic bleed is suspected. He is commenced on an infusion of tranexamic acid. Which of the following best describes its mechanism of action?
Inhibition of plasmin Inhibition of thrombin Inhibition of factor II Inhibition of factor Xa Activation of factor VIII
Inhibition of plasmin
Tranexamic acid inhibits plasmin and this prevents fibrin degradation.
A 34 year old male donates a unit of blood. It is stored at 4 oC. After 72 hours which of the following clotting factors will be most affected?
Factor V Factor II Factor VII Factor IX Factor XI
Factor V
Factors V and VIII are sensitive to temperature which is the reason why FFP is frozen soon after collection.
Cortisol is predominantly produced by which of the following?
Zona fasciculata of the adrenal Zona glomerulosa of the adrenal Zona reticularis of the adrenal Adrenal medulla Posterior lobe of the pituitary
Zona fasciculata of the adrenal
Cortisol is produced by the zona fasciculata of the adrenal gland.
Which of these fluids is not an intravenous colloid?
Gelofusine Dextran 40 Human albumin solution Hydroxyethyl starch Bicarbonate 8.4%
Bicarbonate 8.4%
Bicarbonate is a crystalloid.
A 25 year old man undergoes an appendicetomy for appendicitis. The appendix is submitted for histopathological evaluation. Which of the following is most likely to be identified microscopically?
Macrophages Neutrophils Fibroblasts Lymphocytes Stem cells
Neutrophils
Neutrophil polymorphs are the cell type most commonly encountered in acute inflammation.
A 53 year old man is on the intensive care unit following an emergency abdominal aortic aneurysm repair. He develops abdominal pain and diarrhoea and is profoundly unwell. His abdomen has no features of peritonism. Which of the following arterial blood gas pictures is most likely to be present?
pH 7.45, pO2 10.1, pCO2 3.2, Base excess 0, Lactate 0 pH 7.35, pO2 8.0, pCO2 5.2, Base excess 2, Lactate 1 pH 7.20, pO2 9.0, pCO2 3.5, Base excess -10, Lactate 8 pH 7.29, pO2 8.9, pCO2 5.9, Base excess -4, Lactate 3 pH 7.30, pO2 9.2 pCO2 4.8, Base excess -2, lactate 1
pH 7.20, pO2 9.0, pCO2 3.5, Base excess -10, Lactate 8
This man is likely to have a metabolic acidosis secondary to a mesenteric infarct.
The Cori cycle is important in lactate metabolism in the septic surgical patient. It is used to describe a pathway in which glucose is metabolised anaerobically to lactate in one tissue and the lactate is converted back to glucose in another. Which one of the following relies on this cycle to meet all of its energy needs?
Hepatocyte Leucocyte Erythrocyte Pneumocyte Goblet cells
Erythrocyte
Erythrocytes lack a mitochondria and therefore they generate energy via glycolytic pathways only. All the other cell types have mitochondria and will therefore use the Krebs cycle unless true anaerobic conditions prevail.
A 48 year old women suffers blunt trauma to the head and develops respiratory compromise. As a result she develops hypercapnia. Which of the following effects is most likely to ensue?
Cerebral vasoconstriction Cerebral vasodilation Cerebral blood flow will remain unchanged Shunting of blood to peripheral tissues will occur in preference to CNS perfusion None of the above
Cerebral vasodilation
Hypercapnia will tend to produce cerebral vasodilation. This is of considerable importance in patients with cranial trauma as it may increase intracranial pressure.
A patient is seen in clinic complaining of abdominal pain. Routine bloods show:
Na+ 142 mmol/l K+ 4.0 mmol/l Chloride 104 mmol/l Bicarbonate 19 mmol/l Urea 7.0 mmol/l Creatinine 112 µmol/l
What is the anion gap?
4 mmol/L 14 mmol/L 20 mmol/L 21 mmol/L 23 mmol/L
23 mmol/L
The anion gap may be calculated by using (sodium + potassium) - (bicarbonate + chloride)
= (142 + 4.0) - (104 + 19) = 23 mmol/L
A 73 year old man has an arterial line in situ. On studying the trace the incisura can be seen. What is the physiological event which accounts for this process?
Atrial repolarisation Mitral valve closure Ventricular repolarisation Elastic recoil of the aorta Tricuspid valve closure
Elastic recoil of the aorta
It is the temporary rise in aortic pressure occurring as a result of elastic recoil. its the same thing as the dicrotic notch
A surgeon is considering using lignocaine as local anasthesia for a minor procedure. Which of the following best accounts for its actions?
Blockade of neuronal acetylcholine receptors Blockade of neuronal nicotinic receptors Blockade of neuronal sodium channels Blockade of neuronal potassium channels Blockade of neuronal calcium channels
Blockade of neuronal sodium channels
Lignocaine blocks sodium channels. They will typically be activated first, hence the pain some patients experience on administration.
Which of the substances below is derived primarily from the zona reticularis of the adrenal gland?
Mineralocorticoid hormones Glucocorticoid hormones Sex hormones FSH Vasopressin
Sex hormones
A 28 year old man undergoes a completion right hemicolectomy for treatment of a 5cm appendiceal carcinoid. As part of his follow up he is due to undergo 24 hour urine collection for 5-HIAA. Which of the following causes an elevated 5-HIAA in a 24-hour urine collection?
Naproxen Oranges Flucloxacillin Amiodarone Beef
Naproxen
It is important to be aware of what can falsely elevate 5-HIAA to avoid diagnosing carcinoid syndrome incorrectly. These include:
Food: spinach, cheese, wine, caffeine, tomatoes
Drugs: Naproxen, Monoamine oxidase inhibitors
Recent surgery
A 22 year old man suffers a blunt head injury. He is drowsy and has a GCS of 7 on admission. Which of the following is the major determinant of cerebral blood flow in this situation?
Systemic blood pressure Mean arterial pressure Intra cranial pressure Hypoxaemia Acidosis
Intra cranial pressure
Hypoxaemia and acidosis may both affect cerebral blood flow. However, in the traumatic situation increases in intracranial pressure are far more likely to occur especially when GCS is low. This will adversely affect cerebral blood flow.
A 43 year old man has recurrent episodes of dyspepsia and treatment is commenced with oral antacids. Which of the hormones listed below is released in response to increased serum gastrin levels and decreases intra gastric pH?
Cholecystokinin Histamine Somatostatin Insulin Vasoactive intestinal peptide
Histamine
Histamine is released from enterochromaffin cells in the stomach mucosa which stimulates acid secretion. It is usually released in response to increased serum gastrin levels. Histamine blockers (e.g. cimetidine) were extremely popular treatments until the advent of proton pump inhibitors.
Which main group of receptors does dobutamine bind to?
α-1 α-2 ß-1 ß-2 D-1
ß-1
Dobutamine is a sympathomimetic with both alpha- and beta-agonist properties; it displays a considerable selectivity for beta1-cardiac receptors
Which of the following is responsible for the release and synthesis of calcitonin?
Parathyroid glands Anterior pituitary Thyroid gland Posterior pituitary Adrenal glands
Thyroid gland
Calcitonin has the opposite effect of PTH and is released from the thyroid gland.
What is the half life of insulin in the circulation of a normal healthy adult?
Less than 30 minutes Between 1 and 2 hours Between 2 and 3 hours Between 4 and 5 hours Over 6 hours
Less than 30 minutes
Insulin is degraded by enzymes in the circulation. It typically has a half life of less than 30 minutes. Abnormalities of the clearance of insulin may occur in type 2 diabetes.
Which of the following statements about blood clotting is untrue?
Platelet adhesion to disrupted endothelium is dependent upon von Willebrand factor Protein C is a vitamin K dependent substance The bleeding time provides an assessment of platelet function The prothrombin time tests the extrinsic system Administration of aprotinin during liver transplantation surgery prolongs survival
Administration of aprotinin during liver transplantation surgery prolongs survival
Although aprotinin reduces fibrinolysis and thus bleeding, it is associated with increased risk of death and was withdrawn in 2007. Protein C is dependent upon vitamin K and this may paradoxically increase the risk of thrombosis during the early phases of warfarin treatment.
Which of the following cell types is least likely to be found in a wound 1 week following injury?
Macrophages Fibroblasts Myofibroblasts Endothelial cells Neutrophils
Myofibroblasts
Myofibroblasts are differentiated fibroblasts, in which the cytoskeleton contains actin filaments. These cell types facilitate wound contracture and are the hallmark of a mature wound. They are almost never found in wounds less than 1 month old.
The blood - brain barrier is not highly permeable to which of the following?
Carbon dioxide Barbituates Glucose Oxygen Hydrogen ions
Hydrogen ions
The blood brain barrier is relatively impermeable to highly dissociated compounds.
