Welcome to your Test 13 Which of the following is the primary mechanism of action for local anaesthetics? Inhibition of GABA receptors Blockage of voltage-gated sodium channels Activation of potassium channels Inhibition of NMDA receptors None Which of the following agents is least likely to cause malignant hyperthermia? Sevoflurane Isoflurane Desflurane Nitrous oxide None Which of the following is the most common cause of perioperative hypotension in patients under general anaesthesia? Inadequate fluid replacement Overdose of anaesthetic agents Sympathetic nervous system blockade End-organ hypoperfusion None Which of the following is the most important consideration when selecting an anaesthetic for a patient with a history of porphyria? Avoiding inhalational agents Avoiding barbiturates Avoiding succinylcholine Monitoring serum potassium levels None What is the primary mechanism through which propofol induces sedation? Potentiation of GABA receptor activity Inhibition of NMDA receptors Activation of glycine receptors Blockage of serotonin reuptake None Which of the following is the most appropriate treatment for intraoperative anaphylaxis induced by an anaesthetic agent? Epinephrine Hydrocortisone Naloxone Diphenhydramine None Which of the following is associated with the longest duration of action in regional anaesthesia? Lidocaine Bupivacaine Mepivacaine Ropivacaine None What is the primary cause of "cuffed" endotracheal tube complications in patients with difficult airways? Over-inflation of the cuff Use of too large a tube Trauma from cuff placement Inadequate sedation None Which of the following can cause an increase in the minimum alveolar concentration (MAC) of an inhaled anaesthetic? Pregnancy Hyperthyroidism Hypothermia Chronic alcohol use None Which of the following is a contraindication to the use of succinylcholine for rapid sequence intubation? Hyperkalemia Obesity Hypertension Asthma None What is the most common complication of central venous catheter insertion? Pneumothorax Air embolism Infection Hematoma None Which of the following statements about the use of nitrous oxide in anaesthesia is true? Nitrous oxide is a potent muscle relaxant. Nitrous oxide has no effect on cerebral blood flow. Nitrous oxide can lead to vitamin B12 deficiency with prolonged use. Nitrous oxide does not increase the risk of postoperative nausea and vomiting. None Which of the following is the most likely cause of bradycardia during general anaesthesia? Vagal stimulation due to laryngoscopy Sympathetic nervous system stimulation Blood loss Hypercarbia None Which of the following anaesthetic agents has the least effect on heart rate? Sevoflurane Isoflurane Desflurane Halothane None Which of the following is the primary reason why opioids are often combined with local anaesthetics in regional anaesthesia? To reduce the dose of the local anaesthetic To increase the duration of anaesthesia To prevent the systemic side effects of local anaesthetics To enhance the quality of the block and reduce the risk of complications None Which of the following statements regarding the use of dexmedetomidine in anaesthesia is true? It is an opioid analgesic. It causes profound respiratory depression. It acts as an alpha-2 adrenergic agonist. It increases the MAC of inhaled anaesthetics. None What is the primary cause of "stages of anaesthesia" as described by Guedel's classification? Changes in the central nervous system Increasing doses of local anaesthetics Inhalation of high concentrations of nitrous oxide Blockade of acetylcholine receptors None Which of the following is the most likely consequence of excessive intravenous administration of propofol? Respiratory depression Hypertension Hypoglycemia Tachycardia None Which of the following conditions is most commonly associated with difficult airway management? Obesity Asthma Pregnancy Sleep apnea None Which of the following electrolyte abnormalities is commonly associated with prolonged use of nitrous oxide in anaesthesia? Hypokalemia Hypomagnesemia Hypercalcemia Hypernatremia None What is the most significant risk factor for awareness during general anaesthesia? Use of non-volatile anaesthetics Inadequate dosage of anaesthetics Decreased liver function Patient age None Which of the following is the most common side effect of the use of opioids in anaesthesia? Hypotension Nausea and vomiting Tachycardia Respiratory depression None Which anaesthetic agent is most associated with hepatotoxicity? Sevoflurane Isoflurane Halothane Desflurane None Which of the following is the most common complication of epidural anaesthesia? Post-dural puncture headache Nerve injury Epidural abscess Hypotension None Which of the following monitoring devices is most commonly used to assess the depth of anaesthesia during surgery? Pulse oximeter Bispectral index (BIS) monitor Capnograph ECG None Which of the following conditions would most likely require the use of a neuromuscular blocking agent for endotracheal intubation? Severe asthma Obesity Cervical spine injury Airway obstruction from edema None What is the primary mechanism through which sevoflurane causes anaesthesia? Inhibition of sodium channels GABA receptor activation NMDA receptor antagonism Inhibition of acetylcholine release None Which of the following drugs should be avoided in patients with a history of pseudocholinesterase deficiency? Succinylcholine Rocuronium Vecuronium Atracurium None Which of the following agents is most commonly used to reverse the effects of non-depolarizing neuromuscular blockers? Naloxone Neostigmine Sugammadex Flumazenil None Which of the following is the most likely consequence of administering large amounts of intravenous fluids during surgery? Hypernatremia Pulmonary edema Hypokalemia Cerebral vasoconstriction None Which of the following is the most appropriate treatment for a patient who develops severe bradycardia after the administration of a high dose of opioids? Atropine Naloxone Epinephrine Calcium chloride None Which of the following agents is most likely to cause an increase in intracranial pressure (ICP)? Propofol Isoflurane Nitrous oxide Sevoflurane None Which of the following anaesthetic drugs is least likely to cause respiratory depression? Propofol Fentanyl Ketamine Sevoflurane None What is the most common cause of perioperative hypothermia in patients undergoing general anaesthesia? Low ambient temperature Administration of cold intravenous fluids Inhibition of thermoregulation by anaesthetic agents Blood loss None Which of the following conditions is a contraindication for the use of nitrous oxide? Chronic obstructive pulmonary disease (COPD) Recent abdominal surgery Pregnancy (first trimester) Myasthenia gravis None Which of the following statements regarding the pharmacokinetics of propofol is true? It has a long half-life and can cause prolonged sedation after a single dose. It is metabolized in the liver and eliminated via the kidneys. It undergoes extensive first-pass metabolism in the lungs. It has no effect on cardiovascular function. None Which of the following local anaesthetics has the fastest onset of action? Bupivacaine Lidocaine Ropivacaine Mepivacaine None Which of the following is the primary disadvantage of using sevoflurane as an inhalational anaesthetic in pediatrics? Prolonged recovery time Risk of nephrotoxicity Risk of malignant hyperthermia High incidence of postoperative nausea and vomiting None Which of the following changes occurs with the administration of high-dose inhalational anaesthetics? Increased systemic vascular resistance Increased cardiac output Decreased blood pressure Increased respiratory rate None Which of the following is the most appropriate intervention for preventing post-operative nausea and vomiting (PONV) in high-risk surgical patients? Administering metoclopramide preoperatively Using dexamethasone and a 5-HT3 receptor antagonist Encouraging early oral intake postoperatively Reducing the dosage of anaesthetic agents during surgery None Which of the following is the primary reason why ketamine is particularly useful in patients with trauma or hypovolemic shock? It provides deep sedation without respiratory depression. It increases sympathetic tone, preserving blood pressure. It provides excellent muscle relaxation. It does not require airway protection. None Which of the following agents is most likely to cause a significant increase in the risk of bleeding during surgery? Ketamine Nitrous oxide Desflurane Heparin None Which of the following is the most appropriate anaesthetic technique for a patient with a large anterior mediastinal mass and suspected airway obstruction? General anaesthesia with a muscle relaxant Awake fibreoptic intubation Regional anaesthesia Deep sedation with nasal oxygen None Which of the following drugs is used to reverse opioid induced respiratory depression? Flumazenil Naloxone Sugammadex Neostigmine None Which of the following is the most common cause of intraoperative awareness under general anaesthesia? Equipment malfunction Inadequate anaesthetic dose Patient movement Hypoventilation None What is the primary purpose of using a pulse oximeter during anaesthesia? To assess the depth of anaesthesia To monitor blood pressure To measure the patient’s oxygen saturation To assess the carbon dioxide levels None Which of the following anaesthetic drugs has the least effect on uterine tone and is preferred in obstetric anaesthesia? Sevoflurane Nitrous oxide Isoflurane Propofol None Which of the following conditions is most likely to cause an increased response to local anaesthetic agents? Hypotension Hypercapnia Hyperthyroidism Liver failure None Which of the following is the most likely cause of "silent" hypoxia in anaesthetized patients? Low cardiac output Impaired ventilation Acute respiratory acidosis Pulmonary embolism None Which of the following is the most important factor when considering anaesthesia in a patient with a history of difficult intubation? Use of non-depolarizing muscle relaxants Preoperative airway assessment and planning Avoiding volatile anaesthetics Intraoperative blood pressure monitoring None None Time's up
