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  • Question 1 - The fracture of the medial epicondyle will cause damage to the ulnar nerve....

    Correct

    • The fracture of the medial epicondyle will cause damage to the ulnar nerve. Which of the following motions would be impaired by this type of injury?

      Your Answer: Adduction of the thumb

      Explanation:

      Fracture of the medial epicondyle is most likely to result in damage to the ulnar nerve. The three hypothenar muscles, two medial lumbricals, seven interossei, the adductor pollicis, and the deep head of the flexor pollicis brevis are all innervated by the deep branch of the ulnar nerve.

    • This question is part of the following fields:

      • Anatomy
      • Upper Limb
      78.1
      Seconds
  • Question 2 - Which of the following is NOT a notifiable disease: ...

    Incorrect

    • Which of the following is NOT a notifiable disease:

      Your Answer: Tetanus

      Correct Answer: Chickenpox

      Explanation:

      Chickenpox is not a notifiable disease.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      16.1
      Seconds
  • Question 3 - Regarding gentamicin, which of the following statements is INCORRECT: ...

    Incorrect

    • Regarding gentamicin, which of the following statements is INCORRECT:

      Your Answer: It interferes with bacterial protein synthesis.

      Correct Answer: Gentamicin typically causes acute glomerulonephritis in toxicity.

      Explanation:

      Gentamicin is the aminoglycoside of choice in the UK and is used widely for the treatment of serious infections. It has a broad spectrum but is inactive against anaerobes and has poor activity against haemolytic streptococci and pneumococci. When used for the blind therapy of undiagnosed serious infections it is usually given in conjunction with a penicillin or metronidazole (or both). The main toxic effects are nephrotoxicity and ototoxicity due to damage to the vestibulocochlear nerve (CN VIII).Gentamicin is contraindicated in myasthenia gravis and should be used with caution in renal disease which may result in accumulation and a greater risk of toxic side effects.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      55.5
      Seconds
  • Question 4 - All of the following statements are incorrect about insulin except: ...

    Incorrect

    • All of the following statements are incorrect about insulin except:

      Your Answer:

      Correct Answer: Proinsulin is cleaved into insulin and C peptide.

      Explanation:

      Proinsulin is synthesised as a single-chain peptide. A connecting peptide (C peptide) within storage granules is removed by proteases to yield insulin. Insulin:1. is a polypeptide hormone consisting of two short chains (A and B) linked by disulphide bonds. 2. is produced by beta cells, located centrally within the islets of Langerhans, in the endocrine tissues of the pancreas. 3. release is stimulated initially during eating by the parasympathetic nervous system and gut hormones such as secretin. However, most output is driven by the rise in plasma glucose concentration that occurs after a meal. 4. effects are mediated by the receptor tyrosine kinase.

    • This question is part of the following fields:

      • Endocrine
      • Physiology
      0
      Seconds
  • Question 5 - A patient has a cardiac output of 4.8 L/min and a heart rate...

    Incorrect

    • A patient has a cardiac output of 4.8 L/min and a heart rate of 80 bpm, therefore their stroke volume is:

      Your Answer:

      Correct Answer: 60 mL

      Explanation:

      Cardiac output (CO) = Stroke volume (SV) x Heart rate (HR). Therefore SV = CO/HR = 4.8/80 = 0.06 L = 60 mL.

    • This question is part of the following fields:

      • Cardiovascular
      • Physiology
      0
      Seconds
  • Question 6 - A 61-year-old man complains of crushing chest pain that radiates to his left...

    Incorrect

    • A 61-year-old man complains of crushing chest pain that radiates to his left arm and jaw. An ECG is taken, and the lateral leads show extensive ST depression. His blood pressure is currently 190/123 mmHg, and as part of his treatment, you intend to begin drug therapy to lower it.Which of the following is the INITIAL drug treatment for this patient's BP reduction?

      Your Answer:

      Correct Answer: Glyceryl trinitrate

      Explanation:

      End-organ damage (e.g. encephalopathy, intracranial haemorrhage, acute myocardial infarction or ischaemia, dissection, pulmonary oedema, nephropathy, eclampsia, papilledema, and/or angiopathic haemolytic anaemia) characterises a hypertensive emergency (also known as ‘accelerated hypertension’ or malignant hypertension’ It’s a life-threatening condition that necessitates rapid blood pressure reduction to avoid end-organ damage and a negative outcome.In the presence of cardiac ischaemia, hypertensive emergencies require immediate treatment to prevent myocardial infarction. Similarly, if myonecrosis occurs in the presence of an existing infarction, prompt treatment is required to prevent further myonecrosis. When thrombolysis is used as the primary reperfusion therapy for acute myocardial infarction, blood pressure control is especially important.An intravenous nitrate is the drug of choice in this situation (e.g. GTN). These have a dual purpose in that they can help patients with ischaemic chest pain manage their symptoms. Because lowering blood pressure with nitrates isn’t always enough to achieve optimal results, intravenous beta-blockers are frequently used as a supplement. For this, intravenous atenolol and metoprolol are commonly used.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      0
      Seconds
  • Question 7 - Which of the following best describes the process of opsonisation: ...

    Incorrect

    • Which of the following best describes the process of opsonisation:

      Your Answer:

      Correct Answer: The coating of foreign particles with molecules which allow easier recognition of that cell by phagocytes

      Explanation:

      An opsonin is any molecule that enhances phagocytosis by marking an antigen for an immune response, for example, immunoglobulin or complement. Opsonisation is the molecular mechanism whereby molecules, microbes, or apoptotic cells are chemically modified to have a stronger attraction to the cell surface receptors on phagocytes and natural killer cells. With the antigen coated in opsonins, binding to immune cells is greatly enhanced. Opsonisation also mediates phagocytosis via signal cascades from cell surface receptors.

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
      0
      Seconds
  • Question 8 - Compliance is greater in all but which one of the following: ...

    Incorrect

    • Compliance is greater in all but which one of the following:

      Your Answer:

      Correct Answer: Pulmonary oedema

      Explanation:

      Compliance changes at different lung volumes. Initially at lower lung volumes the compliance of the lung is poor and greater pressure change is required to cause a change in volume. This occurs if the lungs become collapsed for a period of time. At functional residual capacity (FRC) compliance is optimal since the elastic recoil of the lung tending towards collapse is balanced by the tendency of the chest wall to spring outwards. At higher lung volumes the compliance of the lung again becomes less as the lung becomes stiffer. At all volumes, the base of the lung has a greater compliance than the apex. Patients with emphysema have increased compliance. Compliance is affected by a person’s age, sex and height.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      0
      Seconds
  • Question 9 - A patient presents to your Emergency Department with a laceration on their buttocks...

    Incorrect

    • A patient presents to your Emergency Department with a laceration on their buttocks requiring closure with sutures.What stage of wound healing is the first to reach completion?

      Your Answer:

      Correct Answer: Haemostasis

      Explanation:

      The stages of wound healing are: haemostasis, inflammatory, proliferative and remodelling (maturation) phases in that order. The first stage in the healing process of a laceration is haemostasis. Haemostasis is the process of the wound being closed by clotting. The inflammatory phase occurs just after and up to 48 hours after injury– Blood vessels dilate to allow white blood cells, antibodies, growth factors, enzymes and nutrients to reach the wounded area leading to the characteristic signs of inflammation seen. Epithelialisation and angiogenesis are not phases of wound healing but occur during the proliferative phase. This ia after haemolysis and inflammation phases have occurred.The maturation phase is the final phase and occurs when the wound has closed. It involves remodelling of collagen from type III to type I. Apoptosis remove unwanted cells, cellular activity reduces and the number of blood vessels in the wounded area regresses and decreases. This can continues for up to 1 year after injury.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      0
      Seconds
  • Question 10 - Which of the following is an ECG change typically associated with hyperkalaemia: ...

    Incorrect

    • Which of the following is an ECG change typically associated with hyperkalaemia:

      Your Answer:

      Correct Answer: Wide QRS complex

      Explanation:

      Hyperkalaemia causes a rapid reduction in resting membrane potential leading to increased cardiac depolarisation and muscle excitability. This in turn results in ECG changes which can rapidly progress to ventricular fibrillation or asystole. Very distinctive ECG changes that progressively change as the K+level increases:K+>5.5 mmol/l – peaked T waves (usually earliest sign of hyperkalaemia), repolarisation abnormalitiesK+>6.5 mmol/l – P waves widen and flatten, PR segment lengthens, P waves eventually disappearK+>7.0 mmol/l – Prolonged QRS interval and bizarre QRS morphology, conduction blocks (bundle branch blocks, fascicular blocks), sinus bradycardia or slow AF, development of a sine wave appearance (a pre-terminal rhythm)K+>9.0 mmol/l – Cardiac arrest due to asystole, VF or PEA with a bizarre, wide complex rhythm.

    • This question is part of the following fields:

      • Physiology
      • Renal
      0
      Seconds
  • Question 11 - Regarding conduction of nerve impulses, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding conduction of nerve impulses, which of the following statements is CORRECT:

      Your Answer:

      Correct Answer: The action potential in myelinated axons is propagated only at the nodes of Ranvier.

      Explanation:

      An action potential is a self-propagating response, successive depolarisation moving along each segment of an unmyelinated nerve until it reaches the end. It is all-or-nothing and does not decrease in size. Conduction in myelinated fibres is much faster, up to 50 times that of the fastest unmyelinated nerve. Myelinated fibres are insulated except at areas devoid of myelin called nodes of Ranvier. The depolarisation jumps from one node of Ranvier to another by a process called saltatory conduction. Saltatory conduction not only increases the velocity of impulse transmission but also conserves energy for the axon because depolarisation only occurs at the nodes and not along the whole length of the nerve fibre. Larger diameter myelinated nerve fibres conduct nerve impulses faster than small unmyelinated nerve fibres.

    • This question is part of the following fields:

      • Basic Cellular
      • Physiology
      0
      Seconds
  • Question 12 - An analytical study is conducted to compare the risk of stroke between Ticagrelor...

    Incorrect

    • An analytical study is conducted to compare the risk of stroke between Ticagrelor therapy and Warfarin therapy among patients with atrial fibrillation. The following is obtained from the study:No. of patients who took Ticagrelor: 300No. of patients who took Ticagrelor and suffered a stroke: 30No. of patients who took Warfarin: 500No. of patients who took Warfarin and suffered a stroke: 20Compute for the risk ratio of a stroke.

      Your Answer:

      Correct Answer: 2.5

      Explanation:

      Relative risk (RR) is a ratio of the probability of an event occurring in the exposed group versus the probability of the event occurring in the non-exposed group.RR can be computed as the absolute risk of events in the treatment group (ART), divided by the absolute risk of events in the control group (ARC).RR = ART/ARCRR = (30/300) / (20/500)RR = 2.5Recall that:If RR < 1, then the intervention reduces the risk of the outcome.If RR = 1, then the treatment has no effect on the outcome.If RR > 1, then the intervention increases the risk of the outcome.

    • This question is part of the following fields:

      • Evidence Based Medicine
      0
      Seconds
  • Question 13 - You are attending to a patient that has presented with a severe headache...

    Incorrect

    • You are attending to a patient that has presented with a severe headache in the Emergency Department. The patient has signs of cerebral oedema and raised intracranial pressure. You discuss the case with the on-call neurology registrar and decide to prescribe Mannitol. The nurse assisting you asks you to reconsider this management plan as she suspects the patient has a contraindication to Mannitol.Out of the following, what is a contraindication to mannitol?

      Your Answer:

      Correct Answer: Severe cardiac failure

      Explanation:

      Mannitol is the most widely used osmotic diuretic that is most commonly used to reduce cerebral oedema and intracranial pressure. It is recommended to use mannitol for the reduction of CSF pressure/cerebral oedema in a dose of 0.25-2 g/kg as an intravenous infusion over 30-60 minutes. This can be repeated 1-2 times after 4-8 hours if needed.Mannitol has several contraindications and some of them are listed below:1. Anuria due to renal disease2. Acute intracranial bleeding (except during craniotomy)3. Severe cardiac failure4. Severe dehydration5. Severe pulmonary oedema or congestion6. Known hypersensitivity to mannitol

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      0
      Seconds
  • Question 14 - You review a patient with a history of Addison’s disease. He takes 100...

    Incorrect

    • You review a patient with a history of Addison’s disease. He takes 100 mg of hydrocortisone per day to control this.What dose of prednisolone is equivalent to this dose of hydrocortisone? Select ONE answer only.

      Your Answer:

      Correct Answer: 25 mg

      Explanation:

      Prednisolone is four times more potent than hydrocortisone, and therefore, a dose of 25 mg would be equivalent to 100 mg of hydrocortisone.The following table summarises the relative potency of the main corticosteroids compared with hydrocortisone:CorticosteroidPotency relative to hydrocortisonePrednisolone4 times more potentTriamcinolone5 times more potentMethylprednisolone5 times more potentDexamethasone25 times more potent

    • This question is part of the following fields:

      • Endocrine Pharmacology
      • Pharmacology
      0
      Seconds
  • Question 15 - Which of the following statements concerning the facial nerve is INCORRECT? ...

    Incorrect

    • Which of the following statements concerning the facial nerve is INCORRECT?

      Your Answer:

      Correct Answer: Forehead sparing in facial nerve palsy is indicative of a lower motor neuron lesion.

      Explanation:

      In facial nerve palsy, LMN damage will involve the forehead and there will be an inability to close the eyes due to paralysis of the orbicularis oculi or raise the eyebrows due to paralysis of the occipitofrontalis muscle.UMN damage causes sparing of the forehead as the occipitofrontalis and orbicularis oculi muscles have bilateral cortical representation.

    • This question is part of the following fields:

      • Anatomy
      • Cranial Nerve Lesions
      0
      Seconds
  • Question 16 - Regarding aciclovir, which of the following statements is INCORRECT: ...

    Incorrect

    • Regarding aciclovir, which of the following statements is INCORRECT:

      Your Answer:

      Correct Answer: Aciclovir eradicates herpes simplex virus from the body.

      Explanation:

      Aciclovir is active against herpesviruses but does not eradicate latent virus.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
      0
      Seconds
  • Question 17 - Where in the nephron is most K+reabsorbed: ...

    Incorrect

    • Where in the nephron is most K+reabsorbed:

      Your Answer:

      Correct Answer: Proximal tubule

      Explanation:

      Approximately 65 – 70% of filtered K+is reabsorbed in the proximal tubule. Potassium reabsorption is tightly linked to that of sodium and water. The reabsorption of sodium drives that of water, which may carry some potassium with it. The potassium gradient resulting from the reabsorption of water from the tubular lumen drives the paracellular reabsorption of potassium and may be enhanced by the removal of potassium from the paracellular space via the Na+/K+ATPase pump. In the later proximal tubule, the positive potential in the lumen also drives the potassium reabsorption through the paracellular route.

    • This question is part of the following fields:

      • Physiology
      • Renal
      0
      Seconds
  • Question 18 - A 63 year old lady presents to ED with a persistent cough and...

    Incorrect

    • A 63 year old lady presents to ED with a persistent cough and red currant jelly sputum. She has a history of chronic alcohol abuse and has an X-ray which demonstrates a cavitating pneumonia. The most likely causative pathogen is:

      Your Answer:

      Correct Answer: Klebsiella pneumoniae

      Explanation:

      One of the results of Klebsiella pneumoniae is pneumonia that is usually a very severe infection. It is characterised by thick, bloody sputum (red currant jelly sputum), and is associated with complications like lung abscess, cavitation, necrosis, empyema and pleural effusions.

    • This question is part of the following fields:

      • Infections
      • Microbiology
      0
      Seconds
  • Question 19 - A 4-year-old girl is rushed to the Emergency Department by her grandparents after...

    Incorrect

    • A 4-year-old girl is rushed to the Emergency Department by her grandparents after swallowing some of her grandfather's Warfarin tablets. On further questioning, it turns out that she took 5 of his 3 mg tablets which he needs to take due to a history of atrial fibrillation. The child appears healthy well-oriented in time, place and person, and has normal vitals. What is the threshold dose of Warfarin that needs to be ingested for there to be a risk of anticoagulation?

      Your Answer:

      Correct Answer: 0.5 mg/kg

      Explanation:

      The clinical effects of Warfarin occur after a dose of greater than 0.5 mg/kg, and they will be observable 8-10 hours after consumption of the drug. The antidote used for Warfarin is Vitamin K.1. In low-risk cases with no apparent bleeding: an oral dose of 10 mg vitamin K2. If there is clinically significant bleedingan intravenous dose of 250-300 mcg/kgActivated charcoal: in cases of warfarin ingestionbinds to it and reduces the absorption of warfarin the ingestion must have occurred within the last hourThere is, however, rarely a need for the use of activated charcoal because vitamin K is such as safe and effective antidote. Clotting studies, including an INR, can be performed, but small children who have ingested warfarin do not require INRs or follow up if they have been treated with 10 mg vitamin K. This dose of vitamin will completely reverse the anticoagulative effects of warfarin.Perform INR if any of the following are present:1. Delayed presentation (>6 hours)2. Patients with symptoms or signs of anticoagulation3. Possible massive ingestion

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      0
      Seconds
  • Question 20 - Which of the following tracts must be affected if a patient presents with...

    Incorrect

    • Which of the following tracts must be affected if a patient presents with decreased pain and temperature sensation in both lower extremities?

      Your Answer:

      Correct Answer: The lateral spinothalamic tract

      Explanation:

      The main function of the spinothalamic tract is to carry pain and temperature via the lateral part of the pathway and crude touch via the anterior part. The spinothalamic tract pathway is an imperative sensory pathway in human survival because it enables one to move away from noxious stimuli by carrying pain and temperature information from the skin to the thalamus where it is processed and transmitted to the primary sensory cortex. The primary sensory cortex communicates with the primary motor cortex, which lies close to it, to generate rapid movement in response to potentially harmful stimuli. Furthermore, the spinothalamic tract has a role in responding to pruritogens, causing us to itch. Interestingly, itching suppresses the spinothalamic tract neuron response to the histamine effect.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
      0
      Seconds
  • Question 21 - The following all cause a right shift in the oxygen dissociation curve EXCEPT...

    Incorrect

    • The following all cause a right shift in the oxygen dissociation curve EXCEPT for:

      Your Answer:

      Correct Answer: Foetal haemoglobin

      Explanation:

      A decreased affinity of haemoglobin for oxygen (and hence increased ease of dissociation), shown by a right shift in the oxygen dissociation curve, is caused by a fall in pH, a rise in PCO2(the Bohr effect) and an increase in temperature. These changes occur in metabolically active tissues such as in exercise, and encourage oxygen release. The metabolic by-product 2,3-diphosphoglycerate (2,3 -DPG) also causes a right shift; 2, 3 -DPG may also be raised in chronic anaemia, chronic lung disease, or at high altitude. Foetal haemoglobin (HbF) binds 2, 3 -DPG less strongly than does adult haemoglobin (HbA), and so the HbF dissociation curve lies to the left of that for HbA, reflecting its higher oxygen affinity. This helps transfer oxygen from mother to foetus.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
      0
      Seconds
  • Question 22 - A 32-year-old man is dehydrated as he presents with severe vomiting and diarrhoea....

    Incorrect

    • A 32-year-old man is dehydrated as he presents with severe vomiting and diarrhoea. He urgently requires resuscitation with intravenous fluid administration. He is also administered metoclopramide.Which of the following is the true mechanism of action of metoclopramide?

      Your Answer:

      Correct Answer: Dopamine receptor antagonism

      Explanation:

      Metoclopramide is used to treat nausea and vomiting. It works by blocking the central and peripheral D2 (dopamine 2) receptors in the medullary chemoreceptor trigger zone in the vomiting centre (area postrema). It decreases the sensitivity of the visceral sensory nerves that transmit from the GI system to the vomiting centre. Blockade of inhibitory dopamine receptors in the GI tract may allow stimulatory actions of ACh at muscarinic synapses to predominate.At high doses, metoclopramide also blocks type-2 serotonin receptors though the effect is much weaker.

    • This question is part of the following fields:

      • CNS Pharmacology
      • Pharmacology
      0
      Seconds
  • Question 23 - A 67-year-old woman complains of general malaise, nausea, and vomiting. She is perplexed...

    Incorrect

    • A 67-year-old woman complains of general malaise, nausea, and vomiting. She is perplexed and declares that everything 'looks yellow.' Her potassium level is 6.8 mmol/l, according to a blood test.Which of the drugs listed below is most likely to be the cause of her symptoms?

      Your Answer:

      Correct Answer: Digoxin

      Explanation:

      Because digoxin has a narrow therapeutic index, it can cause toxicity both during long-term therapy and after an overdose. Even when the serum digoxin concentration is within the therapeutic range, it can happen.Acute digoxin toxicity usually manifests itself within 2-4 hours of an overdose, with serum levels peaking around 6 hours after ingestion and life-threatening cardiovascular complications following 8-12 hours.Chronic digoxin toxicity is most common in the elderly or those with impaired renal function, and it is often caused by a coexisting illness. The clinical signs and symptoms usually appear gradually over days to weeks.The following are characteristics of digoxin toxicity:Nausea and vomitingDiarrhoeaAbdominal painConfusionTachyarrhythmias or bradyarrhythmiasXanthopsia (yellow-green vision)Hyperkalaemia (early sign of significant toxicity)Some precipitating factors are as follows:Elderly patientsRenal failureMyocardial ischaemiaHypokalaemiaHypomagnesaemiaHypercalcaemiaHypernatraemiaAcidosisHypothyroidismSpironolactoneAmiodaroneQuinidineVerapamilDiltiazem

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
      0
      Seconds
  • Question 24 - Which of the following is an adverse effect of carbamazepine: ...

    Incorrect

    • Which of the following is an adverse effect of carbamazepine:

      Your Answer:

      Correct Answer: Aplastic anaemia

      Explanation:

      Common adverse effects include nausea and vomiting, sedation, dizziness, headache, blurred vision and ataxia. These adverse effects are dose related and are most common at the start of treatment.Other adverse effects include:Allergic skin reactions (and rarely, more serious dermatological conditions)Hyponatraemia (avoid concomitant use with diuretics)Leucopenia, thrombocytopenia and other blood disorders including aplastic anaemiaHepatic impairment

    • This question is part of the following fields:

      • Central Nervous System
      • Pharmacology
      0
      Seconds
  • Question 25 - A 30 year old man presents to ED after a road traffic accident....

    Incorrect

    • A 30 year old man presents to ED after a road traffic accident. Free intraperitoneal fluid is found on FAST (Focussed assessment for sonography in trauma) done in the supine position. Which of these is most likely to be affected?

      Your Answer:

      Correct Answer: Hepatorenal recess

      Explanation:

      Fluid accumulates most often in the hepatorenal pouch (of Morrison) in a supine patient. The hepatorenal pouch is located behind the liver and anterior to the right kidney and is the lowest space in the peritoneal cavity in the supine position.Although the vesicouterine and rectouterine spaces are also potential spaces for fluid accumulation, fluid accumulation in them occur in the erect position.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
      0
      Seconds
  • Question 26 - Which of the following does NOT affect the rate of flow of a...

    Incorrect

    • Which of the following does NOT affect the rate of flow of a liquid through a tube:

      Your Answer:

      Correct Answer: Surface tension

      Explanation:

      Flow through a tube is dependent upon:The pressure difference across the ends of the tube (P1– P2)The resistance to flow provided by the tube (R)This is Darcy’s law, which is analogous to Ohm’s law in electronics:Flow = (P1– P2) / RResistance in the tube is defined by Poiseuille’s law, which is determined by the diameter of the tube and the viscosity of the fluid. Poiseuille’s law is as follows:Resistance = (8VL) / (πR4)Where:V = The viscosity of the fluidL = The length of the tubeR = The radius of the tubeTherefore, in simple terms, resistance is directly proportional to the viscosity of the fluid and the length of the tube and inversely proportional to the radius of the tube. Of these three factors, the most important quantitatively and physiologically is vessel radius.It can be seen that small changes in the radius can have a dramatic effect on the flow of the fluid. For example, the constriction of an artery by 20% will decrease the flow by approximately 60%.Another important and frequently quoted example of this inverse relationship is that of the radius of an intravenous cannula. Doubling the diameter of a cannula increases the flow rate by 16-fold (r4). This is the reason the diameter of an intravenous cannula in resuscitation scenarios is so important.*Please note that knowledge of the detail of Poiseuille’s law is not a requirement of the RCEM Basic Sciences Curriculum.

    • This question is part of the following fields:

      • Basic Cellular
      • Physiology
      0
      Seconds
  • Question 27 - Which of the following does NOT predispose to digoxin toxicity in a patient...

    Incorrect

    • Which of the following does NOT predispose to digoxin toxicity in a patient taking digoxin:

      Your Answer:

      Correct Answer: Hyponatraemia

      Explanation:

      Hypoxia, hypercalcaemia, hypokalaemia and hypomagnesaemia predispose to digoxin toxicity. Care should also be taken in the elderly who are particularly susceptible to digoxin toxicity. Hypokalaemia may be precipitated by use of diuretics. Although hyponatremia can result in the development of other pathological disturbances, it does not potentiate digoxin toxicity.

    • This question is part of the following fields:

      • Cardiovascular
      • Pharmacology
      0
      Seconds
  • Question 28 - Innate, or non-specific, immunity is the immune system we are born with.Which of...

    Incorrect

    • Innate, or non-specific, immunity is the immune system we are born with.Which of the following is NOT an example of innate immunity? Select ONE answer only.

      Your Answer:

      Correct Answer: T-lymphocytes

      Explanation:

      Innate, or non-specific, immunity is the immune system we are born with.There are three aspects of innate immunity:1. Anatomical barriers, such as:The cough reflexEnzymes in tears and skin oilsMucus – which traps bacteria and small particlesSkinStomach acid2. Humoral barriers, such as:The complement systemInterleukin-13. Cellular barriers, such as:NeutrophilsMacrophagesDendritic cellsNatural killer cellsAntibody production is part of the specific, or inducible immune response. T-lymphocytesare responsible for the cell mediated immune response which is part of specific, or inducible immunity.

    • This question is part of the following fields:

      • General Pathology
      • Pathology
      0
      Seconds
  • Question 29 - Which of the following local anaesthetics has the longest duration of action: ...

    Incorrect

    • Which of the following local anaesthetics has the longest duration of action:

      Your Answer:

      Correct Answer: Bupivacaine

      Explanation:

      Bupivacaine has a longer duration of action than the other local anaesthetics, up to 8 hours when used for nerve blocks. It has a slow onset, taking up to 30 minutes for full effect. It is often used in lumbar epidural blockade and is particularly suitable for continuous epidural analgesia in labour, or for postoperative pain relief. It is the principal drug used for spinal anaesthesia.

    • This question is part of the following fields:

      • Anaesthesia
      • Pharmacology
      0
      Seconds
  • Question 30 - Regarding antiemetics, which of the following statements is INCORRECT: ...

    Incorrect

    • Regarding antiemetics, which of the following statements is INCORRECT:

      Your Answer:

      Correct Answer: Of the antiemetics, cyclizine is most commonly associated with acute dystonic reactions.

      Explanation:

      Cyclizine acts by inhibiting histamine pathways and cholinergic pathways involved in transmission from the vestibular apparatus to the vomiting centre. Metoclopramide is a dopamine-receptor antagonist which acts both peripherally in the GI tract and centrally within the chemoreceptor trigger zone. Prochlorperazine is a dopamine-D2 receptor antagonist and acts centrally by blocking the chemoreceptor trigger zone. Metoclopramide and prochlorperazine are both commonly associated with extrapyramidal effects, such as acute dystonic reaction. Cyclizine may rarely cause extrapyramidal effects.

    • This question is part of the following fields:

      • Central Nervous System
      • Pharmacology
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Anatomy (1/1) 100%
Upper Limb (1/1) 100%
Infections (0/2) 0%
Pharmacology (0/2) 0%
Passmed