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Answer2445. #EXPLANATION Low dose estrogen or progesterone only pills need not be stopped as it won’t pose a risk factor for thrombo- embolic phenomenon. #Highyield ● Patients taking high dose estrogen oral contraceptives have an increased risk of postoperative venous thromboembolism. Therefore, stopping the pill 4-6 weeks prior to surgery is needed. Drugs that can be continued on the day of surgery ● Antihypertensive medications (Exceptions are ACE Inhibitors and ARB) ● Cardiac medications (e.g., B-blockers, digoxin) ● Antidepressants, anxiolytics, and other psychiatric medications ● Thyroid medications ● Eye drops ● Heartburn or reflux medications ● Narcotic medications ● Anticonvulsants ● Asthma medications ● Steroids (oral and inhaled) ● Statins ● Levodopa ● Monoamine Oxidase inhibitors are continued when: Anesthesiologists are comfortable with use of MAO-safe procedures, Possibility of exacerbation or precipitation of depressive syndrome. Reference: Harrison's Principles of Internal Medicine, 21st Edition Table 322-2, Page No. 2404 Ans. A. Need not be stopped

Answer2444. #EXPLANATION ● The Jackson Rees modification of Ayre's T piece is specifically designed for providing positive pressure ventilation to spontaneously breathing patients, including infants. ● It consists of a T-shaped connector with a reservoir bag attached to one arm and a pressure-limiting valve attached to the other arm. The patient interface of the T piece is connected to the patient's airway, allowing for the delivery of positive pressure ventilation. Other option: ● Option: B.The Mapleson A circuit is commonly used for short-duration procedures, such as induction of anesthesia or emergency airway management. ● Magill Circuit: The Magill circuit is a modification of the Mapleson A circuit, designed for controlled ventilation . It includes an additional gas sampling port and scavenging system to monitor and remove waste anesthetic gasses. The Magill circuit is used for both spontaneous and controlled ventilation with a face mask or endotracheal tube. ● Option: C. Mapleson C or Waters to-and-fro canister: Mapleson C Circuit: The Mapleson C circuit allows for rebreathing of expired gas, which helps conserve anesthetic gasses and reduce fresh gas flow requirements. The Mapleson C circuit is commonly used for longer-duration procedures where controlled ventilation is required. ● Waters To-and-Fro Canister: This refers to a modification of the Mapleson C circuit that includes a canister filled with soda lime or other absorbent material to remove carbon dioxide from the exhaled gas. ● Option: D. Bain’s circuit is a coaxial anesthesia breathing system used for both controlled and spontaneous ventilation during anesthesia. It consists of a corrugated tubing system with an inner and outer tube. Fresh gas is delivered through the inner tube to the patient, while expired gas is removed through the outer tube. It is commonly used for both pediatric and adult patients undergoing general anesthesia. Reference: Miller Anesthesia Book, 7th Edition, Page No. 514 Ans. A. Jackson Rees modification of Ayre’s T piece

Answer2443. #EXPLANATION ● Thiopentone decreases cerebral blood flow and ICP and is hence cerebro protective. By decreasing cerebral metabolism, thiopentone reduces the brain's energy requirements, leading to a decrease in oxygen consumption and metabolic demand. ● This can be beneficial in situations where cerebral perfusion may be compromised, such as during periods of cerebral ischemia or hypoxia. #Highyield Thiopentone is occasionally used for rapid control of convulsions. ● Gradual i.v. Infusion of subanesthetic doses can be used to facilitate verbal communication with psychiatric patients and for ‘narco analysis’ of criminals. It acts by knocking off guarding. ● Thiopentone can precipitate acute intermittent porphyria in susceptible individuals, and is contraindicated in such subjects. ● Adverse effects Laryngospasm occurs generally when respiratory secretions or other irritants are present in the airways, or when intubation is attempted while anesthesia is light. This can be prevented by atropine premedication and administration of succinylcholine immediately after thiopentone. ● Succinylcholine and thiopentone react chemically—should not be mixed in the same syringe. Other option: ● Option: A.GABA action, calcium channel blocker and free radical removal is wrong statement as it is primarily known for its action as a gamma-aminobutyric acid (GABA) agonist, which enhances the inhibitory effects of GABA it leads to hyperpolarization of neuronal membranes, resulting in inhibition of neurotransmission and ultimately producing the desired effects including sedation, hypnosis, and muscle relaxation. ● Option: B. Increased cerebral blood flow is wrong statement quoted as thiopentone decrease blood pressure, respiratory and cerebral blood flow ● Option: D. Thiopentone has negligible effects on cerebral blood flow (CBF) and oxygenation, its primary mechanism of cerebral protection is through the reduction of cerebral metabolism Reference: Miller Anesthesia Book, 7th Edition, Page No. 50 Ans. C. Decreased cerebral metabolism

Answer2442. #EXPLANATION ● In burn patients, the use of succinylcholine is indeed contraindicated due to the risk of hyperkalemia, which can be life-threatening. ● Burn injuries can lead to the release of potassium from damaged muscle tissue, and succinylcholine can further exacerbate this effect by causing a transient increase in serum potassium levels. This can potentially result in cardiac arrhythmias, cardiac arrest. #Highyield ● Like hemiplegia/paraplegia Burn patients also have extra junctional receptors. Therefore, use of succinylcholine is CI for 1 year. ● Hyperkalemic response can be severe and lead to life-threatening cardiac arrhythmias, including ventricular fibrillation and cardiac arrest. ● Succinylcholine is a trigger for malignant hyperthermia, a rare but potentially fatal hypermetabolic syndrome characterized by rapid and uncontrolled increase in body temperature, muscle rigidity, metabolic acidosis, and hyperkalemia. ● Succinylcholine causes muscle pain, soreness, and fasciculations due to its depolarizing action on motor endplates. ● Succinylcholine administration can transiently increase intraocular pressure, which concerns patients with open-angle glaucoma or other ocular conditions. ● Succinylcholine can cause histamine release from mast cells, leading to hypotension, flushing, and bronchospasm in sensitive individuals. ● Succinylcholine can cause increase in serum potassium levels, particularly in patients with certain risk factors such as burns, trauma, denervating conditions (e.g., spinal cord injury, Guillain-Barré syndrome, and extensive muscle damage e.g., rhabdomyolysis. #Other option: ● Option: B. Atracurium is an intermediate-acting non-depolarizing neuromuscular blocking agent that is metabolized by Hofmann elimination and ester hydrolysis. It is considered suitable for use in burn patients because its metabolism is not dependent on hepatic or renal function. ● Option: C. Mivacurium is metabolized by plasma cholinesterase. Mivacurium is generally safe for use in burn patients, its duration of action may be shorter in patients with reduced plasma cholinesterase activity, which can occur in burn patients due to decreased liver synthesis or increased clearance of plasma cholinesterase. ● Option: D. Vecuronium is an intermediate-acting non-depolarizing neuromuscular blocking agent that is primarily eliminated by hepatic metabolism. Still considered suitable for use in this population because it undergoes primarily biliary excretion rather than renal excretion. Dose adjustments are necessary in patients with significant hepatic dysfunction. Reference: Miller Anesthesia Book, 7th Edition, Page No.344 Ans. A. Succinylcholine

Answer2441. #EXPLANATION ● Metoclopramide is a dopamine antagonist and can exaggerate parkinsonism. Metoclopramide has the potential to cause extrapyramidal symptoms (EPS), which are movement disorders similar to those seen in Parkinson's disease. ● These include tremors, rigidity, bradykinesia, and dystonia. In people with Parkinson's disease, the use of metoclopramide can exacerbate these symptoms or even trigger a parkinsonian crisis. #Highyield ● Antipsychotics: First-generation antipsychotics also known as typical antipsychotics, can block dopamine receptors in the brain and worsen Parkinson's symptoms. Examples of antipsychotics to avoid or use include haloperidol, chlorpromazine, and thioridazine. ● Antiemetics such as metoclopramide and prochlorperazine, can block dopamine receptors in the brain and worsen Parkinson's symptoms. ● Monoamine oxidase inhibitors can interact with other medications and foods containing tyramine, leading to hypertensive crises. ● Antidepressants: Tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs), can exacerbate Parkinson's symptoms or increase the risk of serotonin syndrome . ● Anticholinergic medications such as benztropine and trihexyphenidyl, are sometimes used to manage tremors and rigidity in Parkinson's disease. ● Dopamine receptor antagonists Drugs that block dopamine receptors, such as antiemetics, antipsychotics, and certain anti-hypertensive medications (e.g., metoclopramide, haloperidol, and certain calcium channel blockers), can interfere with the effects of Parkinson's medications. #Other option: ● Option: A. Thiopentone has depressant effects on muscle tone and coordination, potentially exacerbating motor symptoms in individuals with Parkinson's disease. can cause respiratory depression, which is problematic in Parkinson's patients who already have compromised respiratory function. ● Option: B. Ketamine is a dissociative anesthetic that acts primarily as an NMDA receptor antagonist. It is known to increase dopamine release and can induce temporary psychosis-like effects. who are already prone to cognitive and psychiatric symptoms. Ketamine's potential to increase dopamine levels might also interact with Parkinson's medications, potentially altering their effectiveness. ● Option: D. Propofol primarily acts on the GABA receptor and does not directly affect dopamine levels, its potential to cause respiratory depression and hypotension can be concerning in individuals with Parkinson's disease, who already have compromised cardiovascular and respiratory function. Reference: Miller Anesthesia Book, 7th Edition, Page No. 1381 Ans. C. Metoclopramide