Emergency Pharmacology

Emergency Pharmacology Indian Medical PG Question 1: Drug of choice in cardiogenic shock is

• A. Noradrenaline
• B. Dopamine (Correct Answer)
• C. Adrenaline
• D. Phenylephrine

Emergency Pharmacology Explanation: ***Dopamine*** - **Dopamine** is often considered the **drug of choice** in cardiogenic shock because, at low to moderate doses, it increases myocardial contractility and heart rate (positive inotropic and chronotropic effects) while also improving renal perfusion. - Its ability to stimulate **alpha-1, beta-1, and dopaminergic receptors** makes it effective in improving cardiac output and maintaining organ perfusion in this critical condition. *Phenylephrine* - **Phenylephrine** is a selective **alpha-1 adrenergic agonist** that causes potent vasoconstriction and increases systemic vascular resistance. - While it effectively raises blood pressure, it **lacks inotropic effects** and can actually **reduce cardiac output** through reflex bradycardia and increased afterload. - Its strong vasoconstrictive effects without inotropic support make it **not suitable** as a primary agent in cardiogenic shock where cardiac contractility is already compromised. *Noradrenaline* - **Noradrenaline (norepinephrine)** is a potent vasoconstrictor primarily acting on alpha-1 receptors, leading to a significant increase in systemic vascular resistance and blood pressure. - While useful in some forms of shock, its strong vasoconstrictive effect can **increase afterload** and potentially worsen myocardial oxygen demand in cardiogenic shock with already compromised cardiac function. *Adrenaline* - **Adrenaline (epinephrine)** has strong **beta-1 and alpha-1 agonist effects**, leading to increased heart rate, contractility, and vasoconstriction. - While it can improve blood pressure and cardiac output, its significant **chronotropic and arrhythmogenic effects**, along with increased myocardial oxygen demand, make it less favorable than dopamine as a first-line agent in cardiogenic shock.

Emergency Pharmacology Indian Medical PG Question 2: Which drug is used as an adjunct to epinephrine in refractory ventricular fibrillation/ventricular tachycardia during cardiac arrest?

• A. Atropine
• B. Adenosine
• C. High dose vasopressin
• D. Amiodarone infusion (Correct Answer)

Emergency Pharmacology Explanation: ***Amiodarone infusion*** - **Amiodarone** is a **Class III antiarrhythmic** drug commonly used in advanced cardiac life support (ACLS) protocols for refractory **ventricular fibrillation (VF)** or **pulseless ventricular tachycardia (VT)** that persists despite defibrillation and epinephrine [1]. - It works by blocking potassium channels, prolonging repolarization and the refractory period, which helps to stabilize the electrical activity of the heart. *Atropine* - **Atropine** is an anticholinergic drug primarily used to treat **symptomatic bradycardia** by increasing heart rate. - It is not indicated for the treatment of **ventricular fibrillation** or **ventricular tachycardia** during cardiac arrest. *High dose vasopressin* - **Vasopressin** was previously included in some ACLS algorithms as an alternative to epinephrine for **vasoconstrictive effects**, but recent guidelines do not support its routine use in cardiac arrest. - While it can cause **vasoconstriction**, there is no evidence that high-dose vasopressin improves outcomes in refractory VF/VT over epinephrine. *Adenosine* - **Adenosine** is an antiarrhythmic drug used to treat **supraventricular tachycardias (SVTs)** by transiently blocking the AV node. - It is not effective for **ventricular fibrillation** or **ventricular tachycardia** and can even be harmful in these rhythms.

Emergency Pharmacology Indian Medical PG Question 3: Emergency tracheostomy is not indicated in

• A. Bilateral vocal cord paralysis
• B. Foreign body larynx
• C. Acute severe asthma (Correct Answer)
• D. Stridor due to laryngeal growth

Emergency Pharmacology Explanation: ***Acute severe asthma*** - While life-threatening, acute severe asthma is primarily managed with **bronchodilators**, **steroids**, and potentially **non-invasive or invasive ventilation**. - **Tracheostomy** is generally reserved for situations involving upper airway obstruction that cannot be managed by other means, which is not the primary issue in asthma. *Bilateral vocal cord paralysis* - This condition can cause severe **upper airway obstruction** due to the adduction of both vocal cords. - In an emergency setting, a tracheostomy may be life-saving to bypass the obstructed larynx. *Foreign body larynx* - An obstructing **foreign body in the larynx** can lead to immediate and complete airway compromise. - If efforts like the **Heimlich maneuver** or direct laryngoscopy with removal fail, an emergency tracheostomy might be necessary. *Stridor due to laryngeal growth* - A laryngeal growth causing **stridor** indicates significant airway narrowing, which can acutely worsen and lead to respiratory distress. - In cases of severe or rapidly progressive obstruction, an **emergency tracheostomy** is needed to secure the airway below the level of the growth.

Emergency Pharmacology Indian Medical PG Question 4: Which of the following drugs is contraindicated in a patient with raised intracranial pressure ?

• A. Ketamine (Correct Answer)
• B. Midazolam
• C. Propofol
• D. Thiopentone

Emergency Pharmacology Explanation: ***Ketamine*** - **Ketamine** typically causes an increase in **cerebral blood flow** and **intracranial pressure (ICP)**, making it contraindicated in patients with raised ICP. - This effect is due to its action as a **dissociative anesthetic** which can lead to cerebral vasodilation. *Midazolam* - **Midazolam**, a benzodiazepine, can decrease **cerebral metabolic rate** and **cerebral blood flow**, thereby reducing ICP, making it a suitable option for sedation in patients with raised ICP. - It provides **sedation** and **anxiolysis** without significantly increasing ICP. *Propofol* - **Propofol** is a common choice for sedation in patients with raised ICP because it significantly reduces **cerebral blood flow**, **cerebral metabolic rate**, and thus **intracranial pressure**. - Its rapid onset and offset allow for precise control of depth of sedation and neurological assessment. *Thiopentone* - **Thiopentone**, a barbiturate, effectively reduces **cerebral blood flow** and **cerebral metabolic rate**, leading to a decrease in **intracranial pressure**. - It is often used for inducing anesthesia and as a neuroprotective agent in situations with acute brain injury.

Emergency Pharmacology Indian Medical PG Question 5: Which of the following anesthetic agents have good analgesic property? a) Ketamine b) Nitrous oxide c) Thiopentone d) Propofol e) Midazolam

• A. Ketamine and Nitrous oxide (Correct Answer)
• B. Ketamine only
• C. Nitrous oxide and Thiopentone
• D. Ketamine and Propofol
• E. Midazolam only

Emergency Pharmacology Explanation: ***Ketamine and Nitrous oxide*** - **Ketamine** is a dissociative anesthetic with potent **analgesic properties** secondary to its action as an **NMDA receptor antagonist**. - **Nitrous oxide** is an inhalational anesthetic known for its mild to moderate **analgesic effects**, making it useful for sedation and pain relief. *Ketamine only* - While **ketamine** has excellent analgesic properties, this option is incomplete as **nitrous oxide** also contributes significant analgesia among the choices. - Excluding other agents with analgesic properties makes this option less comprehensive than the correct answer. *Ketamine and Propofol* - **Ketamine** possesses strong analgesic effects, but **propofol** is a sedative-hypnotic agent with no significant intrinsic **analgesic properties**. - Propofol provides anesthesia and sedation but typically requires co-administration with opioids for pain control. *Nitrous oxide and Thiopentone* - **Nitrous oxide** provides analgesia, but **thiopentone** (a barbiturate) is primarily an anesthetic and sedative with **no significant analgesic properties**. - Thiopentone can induce unconsciousness rapidly but does not relieve pain. *Midazolam only* - **Midazolam** is a benzodiazepine primarily used for sedation, anxiolysis, and amnesia, with **no intrinsic analgesic properties**. - Its effects can reduce stress and perception of pain, but it does not directly act as an analgesic.

Emergency Pharmacology Flashcard 1 of 5

Question: What is the next treatment step of opioid intoxication after airway maintenance?_____

Answer: Administering Naloxone

Emergency Pharmacology Flashcard 2 of 5

Question: Amiodarone, adrenaline, and _____ are drugs used in the management of VF according to ACLS protocol

Answer: lidocaine

Emergency Pharmacology Flashcard 3 of 5

Question: What are the two main drugs approved by the AHA for resuscitation of a cardiac arrest patient?_____

Answer: Amiodarone and Epinephrine

Emergency Pharmacology Flashcard 4 of 5

Question: Patient refractory to treatment with two doses of lorazepam and an anti-seizure drug (phenytoin) is managed next with _____

Answer: IV Midazolam infusion

Emergency Pharmacology Flashcard 5 of 5

Question: What is the order of inotrope use in polytrauma patients with hemodynamic instability?_____

Answer: Noradrenaline > Vasopressin > Dobutamine > adrenaline