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  • Question 1 - A 14-year-old female is brought to the Emergency Room by her mother after...

    Incorrect

    • A 14-year-old female is brought to the Emergency Room by her mother after a fall from a tree in which she injured her elbow. An elbow fracture is suspected based on the examination findings, and she is given Entonox for analgesia as her elbow is set in a cast. Which one of the following statements regarding this drug is true?

      Your Answer:

      Correct Answer: It can cause inhibition of vitamin B12 synthesis

      Explanation:

      Entonox is a mixture of 50% Oxygen and 50% nitrous oxide and is given in an inhaled form as a quick form of analgesia. Entonox causes non-competitive inhibition of NMDA (N-methyl-D-aspartate) receptors, which are a subtype of the glutamate receptor. It is stored in blue and white cylinders and administered via a pressure regulator and demand valve. The administration of this medicine reduces pain and anxiety in paediatric and dental procedures ands during labour. Effects are apparent after 20 seconds, and peak action occurs after 3 to 5 minutes as it is a drug with a rapid onset and the patient will also recover rapidly from its effects. Entonox is widely used as it does not accumulate in the body and does not cause many side effects. However, a notable side effect is the inhibition of Vitamin B12 synthesis.

    • This question is part of the following fields:

      • Anaesthesia
      • Pharmacology
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  • Question 2 - Which of the following is an example of a non-parametric test: ...

    Incorrect

    • Which of the following is an example of a non-parametric test:

      Your Answer:

      Correct Answer: All of the above

      Explanation:

      All of the above answers are non-parametric tests.

    • This question is part of the following fields:

      • Evidence Based Medicine
      • Statistics
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  • Question 3 - An elderly female has a bacterial infection and you are asked to prescribe...

    Incorrect

    • An elderly female has a bacterial infection and you are asked to prescribe an antibiotic to her. This antibiotic is a nucleic acid synthesis inhibitor.Which of the following antimicrobial drugs will be prescribed to this patient?

      Your Answer:

      Correct Answer: Metronidazole

      Explanation:

      Metronidazole and the other 5-nitroimidazole agents inhibit nucleic acid synthesis by forming toxic free radical metabolites in the bacterial cell that damage DNA. Vancomycin inhibits cell wall peptidoglycan formation by binding the D-Ala-D-Ala portion of cell wall precursors. Erythromycin inhibits protein synthesis and blocks translocation by binding to the 23S rRNA of the 50S ribosomal subunit.Chloramphenicol blocks peptidyl transferase at 50S ribosomal subunit.Gentamicin, an aminoglycoside antibiotic, acts by binding to the 30S subunit of the bacterial ribosome inhibiting the binding of aminoacyl-tRNA and thus preventing initiation of protein synthesis.An overview of the different mechanisms of action of the various types of antimicrobial agents is shown below:1. Inhibition of cell wall synthesis- Penicillins- Cephalosporins- Vancomycin2. Disruption of cell membrane function- Polymyxins- Nystatin- Amphotericin B3. Inhibition of protein synthesis- Macrolides- Aminoglycosides- Tetracyclines- Chloramphenicol4. Inhibition of nucleic acid synthesis- Quinolones- Trimethoprim- 5-nitroimidazoles- Rifampicin5. Anti-metabolic activity- Sulphonamides- Isoniazid

    • This question is part of the following fields:

      • Infections
      • Pharmacology
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  • Question 4 - A 32-year-old asthmatic patient on theophylline as part of her asthma management presents...

    Incorrect

    • A 32-year-old asthmatic patient on theophylline as part of her asthma management presents to the Emergency Department with an unrelated medical condition.Which of these drugs should be avoided?

      Your Answer:

      Correct Answer: Clarithromycin

      Explanation:

      Macrolide antibiotics (e.g. clarithromycin and erythromycin) are cytochrome P450 enzyme inhibitors. They increase blood levels of theophylline leading to hypokalaemia, and potentially increasing the risk of Torsades de pointes when they are prescribed together. Co-prescription with theophylline should be avoided.Factors that enhance theophylline clearance include cigarette smoking, carbamazepine, phenobarbital, phenytoin, primidone, and rifampin. Medications that inhibit clearance include ethanol, ciprofloxacin, erythromycin, verapamil, propranolol, ticlopidine, tacrine, allopurinol, and cimetidine.

    • This question is part of the following fields:

      • Pharmacology
      • Respiratory Pharmacology
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  • Question 5 - Monoamine oxidase is primarily involved in the degradation of which of the following:...

    Incorrect

    • Monoamine oxidase is primarily involved in the degradation of which of the following:

      Your Answer:

      Correct Answer: Noradrenaline

      Explanation:

      Catecholamines are broken down extracellularly and in the liver by catechol-O-methyltransferase (COMT) and intracellularly by monoamine oxidase (MAO).

    • This question is part of the following fields:

      • Endocrine
      • Physiology
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  • Question 6 - Which of the following side effects is most likely caused by erythromycin: ...

    Incorrect

    • Which of the following side effects is most likely caused by erythromycin:

      Your Answer:

      Correct Answer: QT - prolongation

      Explanation:

      The side effects of erythromycin include abdominal pain, anaphylaxis, cholestatic hepatitis, confusion, diarrhoea, dyspepsia, fever, flatulence, hallucinations, hearing loss, headache, hypertrophic pyloric stenosis, hypotension, Interstitialnephritis, mild allergic reactions, nausea, nervous system effects,including seizures, pain, pruritus, pseudomembranous colitis, QT prolongation, rash, skin eruptions, tinnitus, urticaria, ventricular arrhythmias, ventricular tachycardia, vertigo, vomiting

    • This question is part of the following fields:

      • Infections
      • Pharmacology
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  • Question 7 - A patient with a central line in situ for the past 10 days...

    Incorrect

    • A patient with a central line in situ for the past 10 days now has erythema surrounding the catheter insertion site and shows signs of sepsis. You suspect line sepsis.Which of these antibacterial agents would be most appropriate to prescribe for this patient?

      Your Answer:

      Correct Answer: Vancomycin

      Explanation:

      The current recommendation by NICE and the BNF is to use vancomycin as first-line in treatment of septicaemia related to vascular catheter. A broad-spectrum antipseudomonal beta-lactam antibiotic should be added to vancomycin if a Gram-negative sepsis is suspected especially in an immunocompromised patient.In any patient that has had a central venous catheter in situ for a period longer than a week, it should be suspected as the source of sepsis.The features suggesting the vascular catheter as the source of infection include:Presence of the catheter before onset of fever.The absence of another identifiable source of infection.Presence of inflammation or purulent material at the insertion site or along the tunnel.An immunocompetent patient without any underlying disease developing bacteraemia (or fungaemia).

    • This question is part of the following fields:

      • Microbiology
      • Principles Of Microbiology
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  • Question 8 - All of the following single clinical risk groups is considered eligible to receive...

    Incorrect

    • All of the following single clinical risk groups is considered eligible to receive the seasonal influenza vaccination, except:

      Your Answer:

      Correct Answer: Patients with hypertension

      Explanation:

      The following is the list of all the health and age factors that are known to increase a person’s risk of getting serious complications from flu:- Adults 65 years and older- Children younger than 2 years old- Asthma- Neurological and neurodevelopmental conditions- Blood disorders (such as sickle cell disease)- Chronic lung disease (such as chronic obstructive pulmonary disease [COPD] and cystic fibrosis)- Endocrine disorders (such as diabetes mellitus)- Heart disease (such as congenital heart disease, congestive heart failure and coronary artery disease)- Kidney diseases- Liver disorders- Metabolic disorders (such as inherited metabolic disorders and mitochondrial disorders)- People who are obese with a body mass index [BMI] of 40 or higher- People younger than 19 years old on long-term aspirin- or salicylate-containing medications.- People with a weakened immune system due to disease (such as people with HIV or AIDS, or some cancers such as leukaemia) or medications (such as those receiving chemotherapy or radiation treatment for cancer, or persons with chronic conditions requiring chronic corticosteroids or other drugs that suppress the immune system)- People who have had a stroke- Pregnant people and people up to 2 weeks after the end of pregnancy- People who live in nursing homes and other long-term care facilities

    • This question is part of the following fields:

      • Microbiology
      • Principles Of Microbiology
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  • Question 9 - Eosinophils comprise what percentage of circulating white cells: ...

    Incorrect

    • Eosinophils comprise what percentage of circulating white cells:

      Your Answer:

      Correct Answer: 1 - 3%

      Explanation:

      Eosinophils comprise 1 – 3% of circulating white cells. Eosinophils are similar to neutrophils, except that the cytoplasmic granules are coarser and more deeply red staining, and there are rarely more than three nuclear lobes. They are less motile, but longer lived. They enter inflammatory exudates and have a special role in allergic responses, defence against parasites and removal of fibrin formed during inflammation. Thus they play a role in local immunity and tissue repair.

    • This question is part of the following fields:

      • Immune Responses
      • Pathology
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  • Question 10 - Regarding the UK routine childhood immunisation schedule which of the following vaccines is...

    Incorrect

    • Regarding the UK routine childhood immunisation schedule which of the following vaccines is NOT given at 4 months:

      Your Answer:

      Correct Answer: Rotavirus

      Explanation:

      At 4 months the following vaccines are given:Diphtheria, tetanus, pertussis, polio, Hib and hepatitis B (3rd dose)Meningococcal group B (2nd dose)

    • This question is part of the following fields:

      • Immunoglobulins And Vaccines
      • Pharmacology
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  • Question 11 - A patient with abdominal pain, vomiting and bloody diarrhoea develops a low platelet...

    Incorrect

    • A patient with abdominal pain, vomiting and bloody diarrhoea develops a low platelet count and deranged renal function. A diagnosis of haemolytic uraemic syndrome is made.Which of the following organisms is a recognised cause of haemolytic uraemic syndrome? Select ONE answer only.

      Your Answer:

      Correct Answer: Escherichia coli

      Explanation:

      E.Colistrain 0157 causes enterohaemorrhagic diarrhoea and can be followed by haemolytic uraemic syndrome (renal failure, haemolytic anaemia and thrombocytopenia).

    • This question is part of the following fields:

      • Microbiology
      • Specific Pathogen Groups
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  • Question 12 - Regarding meningococcal meningitis, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding meningococcal meningitis, which of the following statements is CORRECT:

      Your Answer:

      Correct Answer: Infection occurs most commonly below the age of 5 years.

      Explanation:

      About half of meningococcal disease occurs in children aged less than five years, and babies are at the highest risk because their immune systems have not yet fully developed. There is a second, smaller increase in risk for older adolescents, mainly for social and behavioural reasons. Infection is most common in winter months. Antibiotics should be given as soon as the diagnosis is suspected (ideally cultures should be performed first but this should not delay treatment), and ceftriaxone/cefuroxime is the first line antibiotic. Only healthcare workers who have been directly exposed to large particle droplets/secretions from the respiratory tract of the index case should receive prophylaxis.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
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  • Question 13 - A patient who is a known case of rheumatoid arthritis presents to the...

    Incorrect

    • A patient who is a known case of rheumatoid arthritis presents to the clinic as his grandson was recently diagnosed with chickenpox. His grandson spent the weekend with her, and he was in close contact with him. He takes 50 mg of prednisolone once daily and has been for the past six months. There is no history of chickenpox.Out of the following, which is TRUE regarding the next plan of action for her care?

      Your Answer:

      Correct Answer: She should receive prophylactic varicella-zoster Immunoglobulin (VZIG)

      Explanation:

      Varicella-zoster immunoglobulin (VZIG) is indicated for post exposure prevention and treatment of varicella. It is recommended as prophylaxis for high-risk patients with no known immunity (i.e. no known previous chickenpox) who have had a significant exposure to varicella-zoster (considered >4 hours close contact).The high-risk groups are:1. Neonates2. Pregnant women3. The immunocompromised (e.g. cancer, immunosuppressive therapies)4. Those on high dose steroids (children on more than 2 mg/kg/day for more than 14 days, or adults on 40 mg/day for more than a week)This patient is at high risk of developing adrenal insufficiency and may need a temporary increase in her steroid dose during infection or stress. It would be inappropriate to stop or wean down her dose of prednisolone and can cause side effects.Since he is on steroids without immunity for chickenpox, he is at risk of developing severe varicella infection, with possible complications including pneumonia, hepatitis and DIC. If he develops a varicella infection, he will need to be admitted and require a specialist review and intravenous Acyclovir.

    • This question is part of the following fields:

      • Immunological Products & Vaccines
      • Pharmacology
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  • Question 14 - A 4-year old boy is taken to the emergency room after a sudden...

    Incorrect

    • A 4-year old boy is taken to the emergency room after a sudden onset of coughing and wheezing. Further investigation reveals that he was drawing quietly in his room, when suddenly, he became anxious and started coughing. The parents also noted that the eraser on top of the pencil was missing.A plain radiographic chest imaging is conducted, and confirmed foreign body aspiration.Which of the following areas in the tracheobronchial tree is the most probable location of the aspirated eraser?

      Your Answer:

      Correct Answer: Right main bronchus

      Explanation:

      In foreign body aspiration, the foreign body is more likely to enter the right main bronchus because it is shorter, wider and more vertical than the left main bronchus. In a patient who is standing or sitting, the foreign body tends to become lodged in the posterobasal segment of the inferior lobe of the right lung.

    • This question is part of the following fields:

      • Anatomy
      • Thorax
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  • Question 15 - Which of the following is diagnostic for acute hepatitis B infection: ...

    Incorrect

    • Which of the following is diagnostic for acute hepatitis B infection:

      Your Answer:

      Correct Answer: anti-HBc IgM

      Explanation:

      Anti-HBc IgM antibodies are diagnostic for acute hepatitis B infection. Anti-HBc IgG antibodies indicate previous exposure, either chronic state or cleared infection. HBsAg is also positive in acute infection but is not diagnostic as this remains positive in chronic infection.

    • This question is part of the following fields:

      • Microbiology
      • Pathogens
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  • Question 16 - Regarding nitrous oxide, which of the following statements is CORRECT: ...

    Incorrect

    • Regarding nitrous oxide, which of the following statements is CORRECT:

      Your Answer:

      Correct Answer: Nitrous oxide may be used for maintenance of anaesthesia where its use allows reduced dosage of other agents.

      Explanation:

      For anaesthesia, nitrous oxide is commonly used in a concentration of around 50 – 66% in oxygen in association with other inhalation or intravenous agents. Nitrous oxide cannot be used as the sole anaesthetic agent due to lack of potency, but is useful as part of a combination of drugs since it allows reduction in dosage of other agents. Exposure to nitrous oxide for prolonged periods, either by continuous or by intermittent administration, may result in megaloblastic anaemia as a result of interference with the action of vitamin B12. Nitrous oxide increases cerebral blood flow and should be avoided in patients with, or at risk of, raised intracranial pressure. Nitrous oxide may be administered by any trained personnel experienced in its use.

    • This question is part of the following fields:

      • Anaesthesia
      • Pharmacology
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  • Question 17 - A 62-year-old woman presents with cold sensitivity, tiredness, and weight gain. A series...

    Incorrect

    • A 62-year-old woman presents with cold sensitivity, tiredness, and weight gain. A series of blood tests done shows a grossly elevated TSH level and a diagnosis of hypothyroidism is made.What is the commonest cause of hypothyroidism worldwide?

      Your Answer:

      Correct Answer: Iodine deficiency

      Explanation:

      Hypothyroidism occurs when there is a deficiency of circulating thyroid hormones. It is commoner in women and is most frequently seen in the age over 60.Iodine deficiency is the commonest cause of hypothyroidism worldwide.In the UK and other developed countries, iodine deficiency is not a problem and autoimmune thyroiditis is the commonest cause.

    • This question is part of the following fields:

      • Endocrine Physiology
      • Physiology
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  • Question 18 - A patient presents with a cough, productive of green sputum and fever. He...

    Incorrect

    • A patient presents with a cough, productive of green sputum and fever. He was commenced on antibiotics 4 days earlier, but his condition has worsened. There is a documented history of penicillin allergy, and the GP prescribed erythromycin.Erythromycin exert its pharmacological effect by binding to?

      Your Answer:

      Correct Answer: The 50S subunit of the bacterial ribosome

      Explanation:

      Macrolides are bacteriostatic antibiotics. They act by binding to the 50S subunit of the bacterial ribosome and inhibit translocation, therefore, inhibiting protein synthesis.

    • This question is part of the following fields:

      • Infections
      • Pharmacology
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  • Question 19 - A 7-year old boy is referred to the Paediatrics Department due to slurred...

    Incorrect

    • A 7-year old boy is referred to the Paediatrics Department due to slurred speech. Upon further examination, the attending physician noted the presence of dysdiadochokinesia, intention tremors, and nystagmus. An MRI is taken, which revealed a brain tumour.Which of the following options is the most probable diagnosis given the clinical features of the patient?

      Your Answer:

      Correct Answer: Astrocytoma of cerebellum

      Explanation:

      Pilocytic astrocytoma (PCA), previously known as cystic cerebellar astrocytoma or juvenile pilocytic astrocytoma, was first described in 1931 by Harvey Cushing, based on a case series of cerebellar astrocytomas; though he never used these terms but rather described a spongioblastoma. They are low-grade, and usually well-circumscribed tumours, which tend to occur in young patients. By the World Health Organization (WHO) classification of central nervous system tumours, they are considered grade I gliomas and have a good prognosis.PCA most commonly occurs in the cerebellum but can also occur in the optic pathway, hypothalamus, and brainstem. They can also occur in the cerebral hemispheres, although this tends to be the case in young adults. Presentation and treatment vary for PCA in other locations. Glial cells include astrocytes, oligodendrocytes, ependymal cells, and microglia. Astrocytic tumours arise from astrocytes and are the most common tumour of glial origin. The WHO 2016 categorized these tumours as either diffuse gliomas or other astrocytic tumours. Diffuse gliomas include grade II and III diffuse astrocytomas, grade IV glioblastoma, and diffuse gliomas of childhood. The other astrocytic tumours group include PCA, pleomorphic xanthoastrocytoma, subependymal giant cell astrocytoma, and anaplastic pleomorphic xanthoastrocytoma.PCA can present with symptoms secondary to the posterior fossa mass effect. This may include obstructive hydrocephalus, with resultant headache, nausea and vomiting, and papilledema. If hydrocephalus occurs before the fusion of the cranial sutures (<18-months-of-age), then an increase in head circumference will likely occur. Lesions of the cerebellar hemisphere result in peripheral ataxia, dysmetria, intention tremor, nystagmus, and dysarthria. In contrast, lesions of the vermis cause a broad-based gait, truncal ataxia, and titubation. Posterior fossa lesions can also cause cranial nerve palsies. Diplopia may occur due to abducens palsy from the stretching of the nerve. They may also have blurred vision due to papilledema. Seizures are rare with posterior fossa lesions.

    • This question is part of the following fields:

      • Anatomy
      • Central Nervous System
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  • Question 20 - Which of the following is caused by an alpha-1 antitrypsin deficiency? ...

    Incorrect

    • Which of the following is caused by an alpha-1 antitrypsin deficiency?

      Your Answer:

      Correct Answer: Early onset emphysema

      Explanation:

      Mucus contains chemicals such as alpha-1-antitrypsin, lysozyme, and IgA that protect the airway from pathogens and damaging proteases released from dead bacteria and immune cells. Early-onset emphysema results from a genetic deficit of alpha-1-antitrypsin, which is caused by unregulated protease activity in the lungs, which results in the degradation of elastin in the alveoli.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
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  • Question 21 - A 71-year-old woman presents with complaints of fatigue and worsening muscle weakness, and...

    Incorrect

    • A 71-year-old woman presents with complaints of fatigue and worsening muscle weakness, and blood tests done shows a potassium level of 2.4 mmol/L.Which is NOT a recognised cause of hypokalaemia?

      Your Answer:

      Correct Answer: Type 4 renal tubular acidosis

      Explanation:

      A plasma potassium less than 3.5 mmol/L defines hypokalaemia.Excessive liquorice ingestion causes hypermineralocorticoidism and leads to hypokalaemia.Gitelman’s syndrome causes metabolic alkalosis with hypokalaemia and hypomagnesaemia. It is an inherited defect of the distal convoluted tubules.Bartter’s syndrome causes hypokalaemic alkalosis. It is a rare inherited defect in the ascending limb of the loop of Henle.Type 1 and 2 renal tubular acidosis both cause hypokalaemia Type 4 renal tubular acidosis causes hyperkalaemia.

    • This question is part of the following fields:

      • Physiology
      • Renal Physiology
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  • Question 22 - Which of the following microbes produces exotoxin: ...

    Incorrect

    • Which of the following microbes produces exotoxin:

      Your Answer:

      Correct Answer: Clostridium tetani

      Explanation:

      Clostridium tetani (causing tetanus) produces the exotoxin tetanospasmin which causes its neurotoxic effects.

    • This question is part of the following fields:

      • Microbiology
      • Principles
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  • Question 23 - Following the administration of a medication for a heart condition, a 69-year-old man...

    Incorrect

    • Following the administration of a medication for a heart condition, a 69-year-old man develops hypothyroidism.Which of the following drugs is most likely to be the cause?

      Your Answer:

      Correct Answer: Amiodarone

      Explanation:

      Amiodarone has a chemical structure that is similar to that of thyroxine and can bind to the nuclear thyroid receptor. It can cause both hypothyroidism and hyperthyroidism, though hypothyroidism is far more common, with 5-10% of patients suffering from it.

    • This question is part of the following fields:

      • Cardiovascular Pharmacology
      • Pharmacology
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  • Question 24 - Approximately how long is the duration of a lidocaine block (when given with...

    Incorrect

    • Approximately how long is the duration of a lidocaine block (when given with adrenaline):

      Your Answer:

      Correct Answer: 90 minutes

      Explanation:

      Lidocaine is a tertiary amine that is primarily used as a local anaesthetic but can also be used intravenously in the treatment of ventricular dysrhythmias.Lidocaine works as a local anaesthetic by diffusing in its uncharged base form through neural sheaths and the axonal membrane to the internal surface of the cell membrane sodium channels. Here it alters signal conduction by blocking the fast voltage-gated sodium channels. With sufficient blockage, the membrane of the postsynaptic neuron will not depolarise and will be unable to transmit an action potential, thereby preventing the transmission of pain signals.Each 1 ml of plain 1% lidocaine solution contains 10 mg of lidocaine hydrochloride. The maximum safe dose of plain lidocaine is 3 mg/kg. When administered with adrenaline 1:200,000, the maximum safe dose is 7 mg/kg. Because of the risk of vasoconstriction and tissue necrosis, lidocaine should not be used in combination with adrenaline in extremities such as fingers, toes, and the nose.The half-life of lidocaine is 1.5-2 hours. Its onset of action is rapid within a few minutes, and it has a duration of action of 30-60 minutes when used alone. Its duration of action is prolonged by co-administration with adrenaline (about 90 minutes).Lidocaine tends to cause vasodilatation when used locally. This is believed to be due mainly to the inhibition of action potentials via sodium channel blocking in vasoconstrictor sympathetic nerves.

    • This question is part of the following fields:

      • Anaesthesia
      • Pharmacology
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  • Question 25 - Which statement about cross-sectional studies is true? ...

    Incorrect

    • Which statement about cross-sectional studies is true?

      Your Answer:

      Correct Answer: They can be used to assess the prevalence of a condition

      Explanation:

      Cross-sectional studies can be used to assess the prevalence of a condition.Cross-sectional studies CANNOT be used to differentiate between cause and effect or establish the sequence of events.They can be used to study multiple outcomes but are NOT suitable for studying rare diseases.

    • This question is part of the following fields:

      • Evidence Based Medicine
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  • Question 26 - The lymph drainage of the anal canal above the pectinate line is initially...

    Incorrect

    • The lymph drainage of the anal canal above the pectinate line is initially to the:

      Your Answer:

      Correct Answer: Internal iliac nodes

      Explanation:

      Above the pectinate line, the anal canal drains to the internal iliac lymph nodes which subsequently drain to the lumbar (para-aortic) nodes.

    • This question is part of the following fields:

      • Abdomen
      • Anatomy
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  • Question 27 - Regarding carbon dioxide transport in the blood, which of the following statements is...

    Incorrect

    • Regarding carbon dioxide transport in the blood, which of the following statements is CORRECT:

      Your Answer:

      Correct Answer: Deoxygenated haemoglobin acts as a buffer for H+ ions.

      Explanation:

      CO2generated in the tissues and water combine to form carbonic acid which readily dissociates to form HCO3-and H+. The first part of this reaction is very slow in plasma, but is accelerated dramatically by the enzyme carbonic anhydrase present in red blood cells. Bicarbonate is therefore formed preferentially in red cells, from which it freely diffuses down its concentration gradient into plasma where it is transported to the lungs. The red cell membrane is impermeable to H+ions which remain in the cell. To maintain electroneutrality, Cl-ions diffuse into the cell to replace HCO3-, an effect known as the chloride shift. Deoxygenated haemoglobin acts as a buffer for H+, allowing the reaction to continue.

    • This question is part of the following fields:

      • Physiology
      • Respiratory
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  • Question 28 - A 60-year-old man with trauma to his cervical spine suffers from damage to...

    Incorrect

    • A 60-year-old man with trauma to his cervical spine suffers from damage to the ansa cervicalis, resulting to paresis of his infrahyoid muscles.All of the following are considered infrahyoid muscles, except:

      Your Answer:

      Correct Answer: Mylohyoid

      Explanation:

      Infrahyoid muscles are also known as “strap muscles” which connect the hyoid, sternum, clavicle and scapula. They are located below the hyoid bone on the anterolateral surface of the thyroid gland and are involved in movements of the hyoid bone and thyroid cartilage during vocalization, swallowing and mastication. They are composed of four paired muscles, organized into two layers.Superficial layer consists of the sternohyoid and omohyoidDeep layer consists of the sternothyroid and thyrohyoid.

    • This question is part of the following fields:

      • Anatomy
      • Head And Neck
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  • Question 29 - Which of the following is NOT a characteristic of megaloblastic anaemia? ...

    Incorrect

    • Which of the following is NOT a characteristic of megaloblastic anaemia?

      Your Answer:

      Correct Answer: Raised reticulocyte count

      Explanation:

      The LDH level is usually markedly increased in severe megaloblastic anaemia. Reticulocyte counts are inappropriately low, representing a lack of production of RBCs due to massive intramedullary haemolysis. These findings are characteristics of ineffective haematopoiesis that occurs in megaloblastic anaemia as well as in other disorders such as thalassemia major.The common feature in megaloblastosis is a defect in DNA synthesis in rapidly dividing cells. To a lesser extent, RNA and protein synthesis are impaired. Unbalanced cell growth and impaired cell division occur since nuclear maturation is arrested. More mature RBC precursors are destroyed in the bone marrow prior to entering the bloodstream (intramedullary haemolysis).

    • This question is part of the following fields:

      • Haematology
      • Pathology
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  • Question 30 - Which of the following best describes a commensal: ...

    Incorrect

    • Which of the following best describes a commensal:

      Your Answer:

      Correct Answer: An organism that is part of the normal flora

      Explanation:

      A commensal is an organism that is part of the normal flora.

    • This question is part of the following fields:

      • Microbiology
      • Principles
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