Cardiovascular Anesthesia

Cardiovascular Anesthesia Indian Medical PG Question 1: Which of the following signs of congestive cardiac failure constitute a major risk to the surgical patient undergoing anaesthesia ?

• A. Pedal oedema
• B. Jugular venous distention and third heart sound (Correct Answer)
• C. Basal crepitations on auscultation
• D. Cardiomegaly

Cardiovascular Anesthesia Explanation: ***Jugular venous distention and third heart sound*** - **Jugular venous distention (JVD)** indicates elevated right atrial pressure and **central venous pressure**, signifying significant volume overload and potential right ventricular dysfunction. - A **third heart sound (S3)** is a strong indicator of **ventricular dysfunction** and high filling pressures, suggesting severe heart failure and poor cardiac reserve, which poses a major risk during anesthesia. *Pedal oedema* - **Pedal edema** can be a sign of fluid overload, but it is a relatively mild and chronic symptom of heart failure compared to acute decompensation. - While it reflects increased hydrostatic pressure, it doesn't alone signify the immediate, critical hemodynamic instability that poses a major perioperative risk. *Basal crepitations on auscultation* - **Basal crepitations** (rales) suggest **pulmonary congestion** due to left ventricular failure, indicating fluid in the small airways. - Although concerning, this sign primarily reflects lung involvement and not necessarily the critical, global hemodynamic compromise indicated by JVD and S3. *Cardiomegaly* - **Cardiomegaly** (enlarged heart) is an imaging finding that reflects chronic cardiac remodeling due to long-standing heart disease. - It indicates a history of heart failure but does not directly reflect the **acute hemodynamic status** and immediate risk of decompensation during surgery.

Cardiovascular Anesthesia Indian Medical PG Question 2: Which of the following agents is not used to provide induced hypotension during surgery ?

• A. Mephenteramine (Correct Answer)
• B. Sodium nitroprusside
• C. Hydralazine
• D. Esmolol

Cardiovascular Anesthesia Explanation: ***Mephenteramine*** - **Mephentermine** is a **vasopressor** used to **increase blood pressure**, acting primarily through the release of **norepinephrine**. - Its effects are opposite to what is desired for **induced hypotension** during surgery, as the goal is to lower systemic blood pressure to reduce blood loss and improve surgical field visibility. *Sodium nitroprusside* - **Sodium nitroprusside** is a potent **vasodilator** that directly relaxes both **arterial** and **venous smooth muscle**, leading to a rapid and significant decrease in blood pressure. - Its rapid onset and offset of action make it a valuable agent for **controlled induced hypotension** during surgery. *Hydralazine* - **Hydralazine** is a **direct-acting arterial vasodilator** that primarily relaxes arterial smooth muscle, leading to a decrease in **peripheral vascular resistance** and blood pressure. - It can be used to induce or maintain **hypotension** during surgery, although its onset of action is slower compared to nitroprusside. *Esmolol* - **Esmolol** is a **short-acting beta-1 selective adrenergic blocker** that reduces heart rate and myocardial contractility, thereby decreasing cardiac output. - By reducing cardiac output, esmolol can contribute to **induced hypotension**, often used in conjunction with vasodilators or in situations where controlling heart rate is also desired.

Cardiovascular Anesthesia Indian Medical PG Question 3: To reduce mortality by CHD, best strategy -

• A. Secondary prevention
• B. Primordial prevention (Correct Answer)
• C. Tertiary prevention
• D. None of the options

Cardiovascular Anesthesia Explanation: ***Primordial prevention*** * This strategy aims to prevent the **development of risk factors** for CHD in the first place, thus preventing the disease itself. * It focuses on promoting healthy lifestyles and environments from early life, targeting populations rather than individuals. *Secondary prevention* * This involves actions taken after an individual has developed **risk factors** for CHD or has been diagnosed with the disease, to prevent recurrence or worsening. * Examples include medication (e.g., statins, antiplatelets) for people with high cholesterol or a history of heart attack. *Tertiary prevention* * This strategy aims to reduce the **impact of an existing disease** on a patient's daily life and prevent further complications, disability, or death. * For CHD, this would include cardiac rehabilitation, surgical interventions like CABG, and managing co-morbidities to improve quality of life and prolong survival. *None of the options* * Given that primordial prevention directly addresses the prevention of risk factors and thus the disease itself, it is the most effective strategy for **reducing overall mortality** at the population level. * Therefore, one of the provided options is indeed the best strategy.

Cardiovascular Anesthesia Indian Medical PG Question 4: Subarachnoid block as anaesthesia is contraindicated in –

• A. Atherosclerotic gangrene
• B. Diabetic gangrene
• C. Buerger's disease
• D. Hemophilia (Correct Answer)

Cardiovascular Anesthesia Explanation: ***Hemophilia*** - Subarachnoid block, which involves puncturing the dura, is contraindicated in patients with **hemophilia** due to the high risk of **spinal hematoma**. - A spinal hematoma can lead to **cord compression** and devastating neurological deficits. *Atherosclerotic gangrene* - This condition involves **peripheral vascular disease** and tissue necrosis, but does not inherently contraindicate subarachnoid block. - In fact, subarachnoid block can be beneficial by providing **sympathectomy**, improving blood flow to the affected limb. *Diabetic gangrene* - Similar to atherosclerotic gangrene, **diabetic gangrene** is a manifestation of peripheral vascular disease often complicated by neuropathy and infection. - There is no direct contraindication to subarachnoid block for this condition itself, provided there are no concurrent coagulopathies or active infections at the needle insertion site. *Buerger's disease* - **Buerger's disease** (thromboangiitis obliterans) is an inflammatory vasculitis of small and medium-sized arteries and veins, primarily in the limbs. - Subarachnoid block may even be indicated to improve blood flow by inducing **sympathectomy**, helping relieve ischemic pain or prevent further tissue damage.

Cardiovascular Anesthesia Indian Medical PG Question 5: The treatment of acute myocardial infarction includes which of the following?

• A. Oral anticoagulants
• B. Aspirin (Correct Answer)
• C. Heparin
• D. Alteplase

Cardiovascular Anesthesia Explanation: ***Aspirin*** - **Aspirin** is a cornerstone of acute myocardial infarction treatment due to its **antiplatelet effects**, which reduce thrombus formation in the coronary arteries [4]. - It works by **irreversibly inhibiting cyclooxygenase-1 (COX-1)**, thereby preventing the synthesis of thromboxane A2, a potent platelet aggregator [4]. *Heparin* - **Heparin** (unfractionated or low molecular weight) is an **anticoagulant** often used adjunctively in acute MI, particularly in patients undergoing percutaneous coronary intervention (PCI) or with concurrent atrial fibrillation [1]. - Its primary role is to **prevent further clot formation** rather than directly dissolving existing clots, making it not the initial, primary treatment for MI itself. *Alteplase* - **Alteplase** is a **fibrinolytic agent** used in acute ST-elevation myocardial infarction (STEMI) to **dissolve existing clots** and restore blood flow [3]. - While effective, it is not universally indicated for *all* acute MI cases and has specific contraindications, making it a secondary rather than primary initial treatment choice in many scenarios when compared to aspirin [2]. *Oral anticoagulants* - **Oral anticoagulants** (e.g., warfarin, direct oral anticoagulants) are primarily used for **long-term prevention** of thromboembolic events, such as in atrial fibrillation or after venous thromboembolism. - They are generally **not used in the immediate acute phase of MI** as the primary treatment due to their slower onset of action and different mechanisms compared to antiplatelet drugs like aspirin.

Cardiovascular Anesthesia Flashcard 1 of 5

Question: Which inhalational agent is associated with myocardial depression and sensitization of the myocardium to arrhythmias?_____

Answer: Halothane

Cardiovascular Anesthesia Flashcard 2 of 5

Question: _____ is the anticoagulant of choice for patients requiring cardiopulmonary bypass.

Answer: Unfractionated heparin

Cardiovascular Anesthesia Flashcard 3 of 5

Question: Thiopentone should be avoided in hypovolemic or shock patients because of the significant reduction in _____

Answer: cardiac output

Cardiovascular Anesthesia Flashcard 4 of 5

Question: What is the inhalational anesthetic of choice in patients with cardiac disease?_____

Answer: Isoflurane

Cardiovascular Anesthesia Flashcard 5 of 5

Question: Cardiopulmonary bypass circuits activate factor _____ which can lead to clotting in the oxygenator.

Answer: XII