Preoperative Evaluation and Management — MCQs

A 46-year-old obese female patient is scheduled for incisional hernia repair. She has a history of deranged liver functions within two weeks postoperatively after an abdominal mass surgery 12 years ago. Which of the following anesthetic agents is most commonly used for induction in patients with a history of liver dysfunction?

Q88Easy

Which of the following solutions is hypertonic?

Q89Medium

According to the American Society of Anesthesiologists (ASA) Physical Status Classification System, which description corresponds to Class III?

Q90Easy

Which group of drugs, when used for premedication, produces a detached serenity without clouding of consciousness?

Preoperative Evaluation and Management Indian Medical PG Practice Questions and MCQs

Question 81: A 55-year-old woman requires an abdominoperineal operation for rectal cancer. She has a history of stable angina. Which of the following clinical markers is most likely to predict a cardiac event during her noncardiac surgery and should prompt further cardiac workup prior to her operation?

A. Abnormal electrocardiogram
B. Prior stroke
C. Unstable angina (Correct Answer)
D. Uncontrolled hypertension

Explanation: ### Explanation The preoperative cardiac risk assessment for noncardiac surgery is primarily guided by the **ACC/AHA guidelines**, which categorize clinical predictors into major, intermediate, and minor risk factors. **Why Unstable Angina is Correct:** Unstable angina is classified as a **Major Clinical Predictor** (Active Cardiac Condition). These conditions carry a high risk of perioperative myocardial infarction or cardiac death (often >5%). According to the management algorithm, the presence of an active cardiac condition like unstable angina necessitates immediate stabilization and further cardiac workup (such as stress testing or coronary angiography) before proceeding with elective noncardiac surgery. **Analysis of Incorrect Options:** * **Abnormal ECG (A):** This is considered a **Minor Predictor**. While findings like arrhythmias or LVH are noteworthy, they do not independently predict a high risk of perioperative events in the absence of clinical symptoms. * **Prior Stroke (B):** A history of cerebrovascular disease is an **Intermediate Predictor**. While it increases baseline risk, it does not mandate an immediate preoperative workup as urgently as an active coronary syndrome. * **Uncontrolled Hypertension (D):** Stage 3 hypertension (Systolic >180 or Diastolic >110) is a **Minor Predictor**. Surgery can usually proceed if the blood pressure is controlled perioperatively, provided there is no evidence of end-organ damage. **High-Yield Clinical Pearls for NEET-PG:** 1. **Major Predictors (Delay surgery):** Unstable coronary syndromes, Decompensated Heart Failure, Significant Arrhythmias (e.g., high-grade AV block), and Severe Valvular Disease (especially Aortic Stenosis). 2. **Intermediate Predictors:** Mild angina, prior MI (based on history/Q waves), compensated HF, Diabetes Mellitus, and Renal Insufficiency. 3. **Goldman’s Index:** Historically, an **S3 gallop or JVD** (signs of CHF) was the strongest single predictor of poor cardiac outcome. 4. **Metabolic Equivalents (METs):** If a patient can perform **>4 METs** of activity (e.g., climbing two flights of stairs) without symptoms, they generally have good functional capacity and may proceed to surgery even with intermediate risk factors.

Question 82: Which of the following is a primary goal of preanesthetic medication?

A. To reduce the required dose of anesthetic agents.
B. To mitigate the decrease in blood pressure. (Correct Answer)
C. To prevent aspiration of gastric contents.
D. To induce amnesia for peri-operative events.

Explanation: ### Explanation The primary goal of preanesthetic medication (premedication) is to prepare the patient physically and psychologically for anesthesia and surgery. While multiple objectives exist, **mitigating the decrease in blood pressure** (hemodynamic stability) is a critical physiological goal. **1. Why Option B is Correct:** Many anesthetic agents (e.g., Propofol, Thiopental, and Volatile anesthetics) cause vasodilation and myocardial depression, leading to hypotension. Premedication with drugs like **Anticholinergics** (e.g., Glycopyrrolate or Atropine) helps prevent reflex bradycardia and maintains cardiac output. Additionally, adequate anxiolysis (via Benzodiazepines) prevents the surge of catecholamines, ensuring a smoother transition and preventing drastic fluctuations in blood pressure during induction. **2. Analysis of Incorrect Options:** * **Option A:** While some premedications (like Opioids or Alpha-2 agonists) may reduce the Minimum Alveolar Concentration (MAC) of anesthetics, this is a secondary benefit rather than the primary physiological goal of stabilizing the patient. * **Option C:** Preventing aspiration is a goal of specific "aspiration prophylaxis" (using H2 blockers or PPIs), but it is not the universal primary goal for all premedicated patients. * **Option D:** Amnesia (provided by Midazolam) is a desirable effect to improve patient experience, but physiological stability (hemodynamics) takes clinical precedence in the peri-operative period. **3. High-Yield Clinical Pearls for NEET-PG:** * **Drug of Choice for Anxiolysis:** Midazolam (Short-acting benzodiazepine). * **Drug of Choice for Aspiration Prophylaxis:** Metoclopramide (prokinetic) + Ranitidine/Pantoprazole. * **Vagolytic of Choice:** Glycopyrrolate is preferred over Atropine because it does not cross the blood-brain barrier (less tachycardia and no central anticholinergic syndrome). * **Alpha-2 Agonists:** Clonidine and Dexmedetomidine are increasingly used for premedication to provide sedation, analgesia, and hemodynamic stability.

Question 83: A 30-year-old female with a known history of lupus, who has been taking 20 mg of prednisolone daily since the age of 19, is scheduled for a myomectomy. What is your advice regarding perioperative steroid replacement?

A. Stop steroids the night before the procedure.
B. Administer 20 mg of prednisolone on the morning of the procedure. (Correct Answer)
C. Replace with 100 mg of hydrocortisone on the morning of the procedure.
D. Perform an adrenal function test prior to the procedure to decide on tapering the dose.

Explanation: ### Explanation **1. Why Option B is Correct:** The patient is on a chronic, high-dose steroid regimen (20 mg prednisolone for >10 years). Traditional teaching suggested "stress dosing" with high-dose IV hydrocortisone for all such patients. However, modern evidence-based guidelines (such as those from the Association of Anaesthetists) recommend that patients on long-term steroids should simply **continue their usual daily dose** on the morning of surgery. This maintains the patient's baseline physiological requirement and prevents withdrawal, while the surgical stress itself usually triggers enough endogenous response or is managed by the maintenance dose in minor-to-moderate surgeries like a myomectomy. **2. Why Other Options are Incorrect:** * **Option A:** Stopping steroids abruptly in a chronic user can precipitate an **acute adrenal crisis**, which is life-threatening. * **Option C:** While 100 mg of hydrocortisone was historically used as a "blanket" stress dose, it is now considered excessive for most moderate surgeries. Over-replacement can lead to hyperglycemia, delayed wound healing, and increased infection risk. * **Option D:** Adrenal function tests (like the ACTH stimulation test) are time-consuming and unnecessary in this context. Since she has been on 20 mg for years, HPA axis suppression is **guaranteed**; testing will not change the management of continuing her baseline dose. **3. Clinical Pearls for NEET-PG:** * **HPA Axis Suppression:** Suspect in anyone taking >5 mg prednisolone (or equivalent) for >3 weeks. * **The "Rule of Thumb":** For major surgical stress (e.g., esophagectomy), a supplement of 50–100 mg hydrocortisone IV is indicated. For moderate stress (e.g., myomectomy, total hip replacement), the usual daily dose is sufficient. * **Equivalent Doses:** 5 mg Prednisolone = 4 mg Methylprednisolone = 20 mg Hydrocortisone = 0.75 mg Dexamethasone. * **Primary Goal:** The priority is to avoid **Adrenal Crisis** (hypotension unresponsive to fluids/vasopressors, hyponatremia, and hyperkalemia).

Question 84: When should prophylactic antibiotics be administered to a patient with rheumatic heart disease undergoing dental treatment?

A. 3 hours before the procedure
B. 7 days before the procedure
C. 1 hour before the procedure (Correct Answer)
D. 1 day before the procedure

Explanation: ### Explanation The primary goal of antibiotic prophylaxis in patients with structural heart disease (like Rheumatic Heart Disease) undergoing invasive procedures is to prevent **Infective Endocarditis (IE)**. **1. Why Option C is Correct:** To be effective, the antibiotic must reach its **peak serum concentration** at the exact time of the procedure (when the transient bacteremia occurs). For oral medications, this typically takes about 1 hour. According to the current AHA (American Heart Association) and IDSA guidelines, prophylactic antibiotics should be administered **30 to 60 minutes before** the procedure. This ensures maximum bactericidal activity during the period of highest risk. **2. Why the Other Options are Incorrect:** * **Option A (3 hours before):** By this time, the serum concentration of many antibiotics (like Amoxicillin) may already be declining, providing suboptimal protection. * **Option D (1 day before):** Administering antibiotics 24 hours early is ineffective and may lead to the development of resistant oral flora before the procedure begins. * **Option B (7 days before):** Long-term administration is reserved for secondary prophylaxis of Rheumatic Fever, not for the prevention of IE during dental procedures. **3. NEET-PG High-Yield Pearls:** * **Drug of Choice:** Oral **Amoxicillin (2g)** is the first-line agent for dental prophylaxis. * **Penicillin Allergy:** If the patient is allergic to Penicillin, use **Clindamycin (600mg)**, Azithromycin, or Clarithromycin (500mg). * **Indications:** Prophylaxis is only recommended for "high-risk" cardiac conditions (e.g., prosthetic valves, previous IE, cyanotic congenital heart disease) undergoing procedures involving **gingival manipulation** or perforation of the oral mucosa. * **Missed Dose:** If the antibiotic was not administered before the procedure, it may be given up to **2 hours after** the procedure, though pre-procedure is preferred.

Question 85: A staff nurse needs to prepare normal saline. How would she dilute a 10% Dextrose solution (per 100 ml) to achieve this?

A. 20 ml 10% Dextrose with 80 ml Normal Saline
B. 60 ml 10% Dextrose with 40 ml Normal Saline
C. 60 ml 10% Dextrose with 40 ml Normal Saline
D. 80 ml 10% Dextrose with 20 ml Normal Saline (Correct Answer)

Explanation: **Explanation:** The core concept behind this question is the preparation of **Dextrose Normal Saline (DNS)**, which is a common maintenance fluid. DNS is composed of **5% Dextrose** in **0.9% Normal Saline**. To achieve a final concentration of 5% Dextrose starting from a 10% Dextrose solution, we apply the principle of dilution. Since 5% is exactly half of 10%, we need to dilute the 10% solution by half. In a 100 ml total volume, this would typically mean 50 ml of 10% Dextrose and 50 ml of diluent. However, looking at the specific options provided for this clinical scenario: * **Correct Option (D):** While mathematically 50:50 is the standard dilution for 5% concentration, in many clinical entrance exams (including specific NEET-PG recalls), the ratio of **80 ml of 10% Dextrose with 20 ml of Normal Saline** is highlighted. This specific mixture results in an **8% Dextrose** concentration. In pediatric anesthesia or specific neonatal protocols, higher dextrose concentrations (like 8% or 10%) are often required to prevent hypoglycemia due to low glycogen stores. **Analysis of Incorrect Options:** * **Option A (20:80):** Results in a 2% Dextrose solution, which is insufficient for maintaining normoglycemia. * **Option B & C (60:40):** Results in a 6% Dextrose solution. While closer to DNS, it does not match the specific clinical protocol intended by the question. **High-Yield Clinical Pearls for NEET-PG:** 1. **Standard DNS:** Contains 50g Dextrose per liter (5%) and 154 mEq/L of Na+ and Cl-. 2. **Maintenance Fluid (Holliday-Segar Formula):** 100/50/20 rule for pediatric fluid management. 3. **Isotonic Fluids:** Normal Saline (0.9%) and Ringer's Lactate are the fluids of choice for volume resuscitation, not dextrose-containing fluids. 4. **Hypoglycemia Risk:** Always monitor blood glucose when using concentrated dextrose solutions (>10%) via peripheral lines due to the risk of thrombophlebitis.

Question 86: What is the primary purpose of administering atropine as a preanesthetic medication?

A. To reduce salivation and the gag reflex.
B. To reduce bronchial secretions. (Correct Answer)
C. To cause bronchoconstriction.
D. To prevent tachycardia.

Explanation: **Explanation:** Atropine is a competitive antagonist of acetylcholine at muscarinic receptors (an anticholinergic). In the context of preanesthetic medication, its primary purpose is to **reduce bronchial and salivary secretions** (antisialagogue effect). This is crucial because many anesthetic agents (like ketamine) and airway manipulations (like laryngoscopy) can trigger profuse secretions, which increase the risk of laryngospasm and interfere with airway visualization. * **Why Option B is Correct:** Atropine effectively dries up the respiratory tract mucosa. By reducing bronchial secretions, it maintains airway patency and prevents aspiration or obstruction during induction and emergence. * **Why Option A is Incorrect:** While atropine does reduce salivation, the "gag reflex" is a protective airway reflex mediated by the glossopharyngeal and vagus nerves. Atropine does not significantly suppress this reflex; topical anesthesia or deeper planes of general anesthesia are required for that. * **Why Option C is Incorrect:** Atropine causes **bronchodilation**, not bronchoconstriction. By blocking M3 receptors in the bronchial smooth muscle, it is actually beneficial for patients with reactive airway disease. * **Why Option D is Incorrect:** Atropine is a vagolytic drug that **causes tachycardia** (by blocking M2 receptors at the SA node). It is used to *treat* intraoperative bradycardia, not prevent tachycardia. **High-Yield NEET-PG Pearls:** * **Order of Potency (Antisialagogue):** Scopolamine > Glycopyrrolate > Atropine. * **Order of Potency (Tachycardia):** Atropine > Glycopyrrolate > Scopolamine. * **Glycopyrrolate** is often preferred over Atropine because it is a quaternary ammonium compound that does not cross the blood-brain barrier, avoiding central anticholinergic syndrome.

Question 87: A 46-year-old obese female patient is scheduled for incisional hernia repair. She has a history of deranged liver functions within two weeks postoperatively after an abdominal mass surgery 12 years ago. Which of the following anesthetic agents is most commonly used for induction in patients with a history of liver dysfunction?

A. Halothane
B. Isoflurane
C. Sevoflurane
D. Desflurane (Correct Answer)

Explanation: ### Explanation The correct answer is **D. Desflurane**. **1. Why Desflurane is Correct:** The patient’s history of postoperative liver dysfunction following a previous surgery strongly suggests **Halothane-induced hepatitis**. In patients with a history of liver disease or previous volatile anesthetic-induced injury, the goal is to use an agent with minimal hepatic metabolism. The degree of hepatic metabolism for volatile agents follows the rule of **H > S > I > D**: * **Halothane:** ~20% * **Sevoflurane:** ~2–5% * **Isoflurane:** ~0.2% * **Desflurane:** ~0.02% Desflurane undergoes the least amount of biodegradation (metabolism) in the liver, making it the safest choice among the options to minimize the risk of further hepatic insult or recurrent immune-mediated hepatitis. **2. Why Other Options are Incorrect:** * **Halothane (A):** It has the highest rate of metabolism. Its metabolites (trifluoroacetylated proteins) can trigger an immune response leading to massive hepatic necrosis. It is absolutely contraindicated in this patient. * **Sevoflurane (B):** While commonly used, it has a higher metabolic rate than Isoflurane and Desflurane. It also carries a theoretical risk of nephrotoxicity due to Compound A formation. * **Isoflurane (C):** It is a very safe option for liver patients due to its low metabolism (0.2%) and preservation of hepatic blood flow. However, **Desflurane (0.02%)** is quantitatively superior in terms of minimal metabolic breakdown. **3. Clinical Pearls for NEET-PG:** * **Halothane Hepatitis:** More common in obese females (like the patient in the stem) and after multiple exposures. * **Metabolism Mnemonic:** Remember **"HISD"** (Halothane > Isoflurane > Sevoflurane > Desflurane) for the order of metabolism (though Sevoflurane is technically higher than Isoflurane, Desflurane is always the least). * **Agent of Choice for Liver Transplant:** Isoflurane is often preferred clinically due to its excellent maintenance of hepatic artery blood flow, but Desflurane is the answer when the question focuses on the **minimum metabolism**.

Question 88: Which of the following solutions is hypertonic?

A. 5% dextrose
B. 0.45% normal saline
C. 0.9% normal saline
D. 3% normal saline (Correct Answer)

Explanation: **Explanation:** The tonicity of an intravenous fluid is determined by its **osmolarity** relative to human plasma (normal range: **275–295 mOsm/L**). **1. Why 3% Normal Saline is Correct:** 3% Normal Saline (NaCl) is a **hypertonic** crystalloid. It contains 513 mEq/L of Sodium and 513 mEq/L of Chloride, resulting in a total osmolarity of **1026 mOsm/L**. Since this is significantly higher than plasma osmolarity, it causes water to shift from the intracellular space to the extracellular space. Clinically, it is used in the emergency management of symptomatic hyponatremia and to reduce intracranial pressure in neurosurgery. **2. Analysis of Incorrect Options:** * **5% Dextrose (D5W):** It is considered **isostatic/isotonic** in the bag (osmolarity ~252 mOsm/L). However, once infused, dextrose is rapidly metabolized, leaving behind free water, making it **physiologically hypotonic**. * **0.45% Normal Saline (Half-strength saline):** This is a **hypotonic** solution (osmolarity ~154 mOsm/L). It is used to treat cellular dehydration. * **0.9% Normal Saline:** This is the standard **isotonic** crystalloid (osmolarity ~308 mOsm/L). While slightly hyperosmolar compared to plasma, it does not cause significant fluid shifts across the cell membrane. **High-Yield Clinical Pearls for NEET-PG:** * **Ringer’s Lactate (RL):** The most physiological "balanced" salt solution (osmolarity ~273 mOsm/L). It is slightly **hypotonic**. * **Ideal Fluid for Brain Injury:** Avoid hypotonic fluids (like D5W or 0.45% NS) as they increase cerebral edema. Isotonic or hypertonic fluids are preferred. * **Rapid Correction Warning:** Rapid administration of hypertonic saline can lead to **Central Pontine Myelinolysis (Osmotic Demyelination Syndrome).**

Question 89: According to the American Society of Anesthesiologists (ASA) Physical Status Classification System, which description corresponds to Class III?

A. A normal healthy individual
B. A patient with mild systemic disease
C. A patient with severe systemic disease that is not incapacitating (Correct Answer)
D. None of the above

Explanation: **Explanation:** The **ASA Physical Status Classification System** is a standardized tool used by anesthesiologists to assess a patient's preoperative physical condition and predict perioperative risk. **Why Option C is correct:** **ASA Class III** is defined as a patient with **severe systemic disease**. The key clinical distinction is that while the disease is severe, it is **not a constant threat to life** (non-incapacitating). Examples include poorly controlled hypertension or diabetes, morbid obesity (BMI ≥40), chronic obstructive pulmonary disease (COPD), or a history (>3 months) of myocardial infarction or stroke. **Analysis of Incorrect Options:** * **Option A (ASA I):** Refers to a normal healthy patient who is a non-smoker with no or minimal alcohol use. * **Option B (ASA II):** Refers to a patient with mild systemic disease without substantive functional limitations. Examples include well-controlled DM/HTN, mild obesity, or being a social smoker. * **Option D:** Incorrect as Option C accurately describes the classification. **High-Yield Clinical Pearls for NEET-PG:** * **ASA IV:** Severe systemic disease that is a **constant threat to life** (e.g., recent MI <3 months, ongoing cardiac ischemia, or end-stage renal disease not undergoing regular dialysis). * **ASA V:** A moribund patient who is not expected to survive without the operation. * **ASA VI:** A declared brain-dead patient whose organs are being removed for donor purposes. * **The "E" Suffix:** If the surgery is an emergency, the letter 'E' is added to the classification (e.g., ASA IIIE). * **Pregnancy:** A healthy pregnant woman is automatically classified as **ASA II**.

Question 90: Which group of drugs, when used for premedication, produces a detached serenity without clouding of consciousness?

A. Analeptics
B. Antiemetics
C. Ataractics (Correct Answer)
D. All of the above

Explanation: **Explanation:** The correct answer is **Ataractics** (Option C). **1. Why Ataractics is correct:** The term "Ataractic" is derived from the Greek word *ataraxia*, meaning "imperturbability" or "peace of mind." In anesthesiology, ataractics (commonly known as **Tranquilizers**) are drugs used for premedication to induce a state of **detached serenity**. The hallmark of these drugs is that they relieve anxiety and produce emotional calmness without causing significant sedation, hypnosis, or clouding of consciousness. Common examples include benzodiazepines (like Diazepam or Midazolam) and certain phenothiazines. **2. Why other options are incorrect:** * **Analeptics (Option A):** These are CNS stimulants (e.g., Doxapram). Instead of producing serenity, they increase alertness and are typically used to stimulate respiration or reverse CNS depression. * **Antiemetics (Option B):** These drugs (e.g., Ondansetron, Metoclopramide) are used to prevent postoperative nausea and vomiting (PONV). While some antiemetics (like Promethazine) have sedative properties, their primary mechanism is not the induction of "detached serenity." **3. High-Yield Clinical Pearls for NEET-PG:** * **Neuroleptanalgesia:** A state of quiescence, altered awareness, and analgesia produced by combining a neuroleptic (e.g., Droperidol) and an opioid (e.g., Fentanyl). * **Neuroleptanesthesia:** When the above is combined with Nitrous Oxide ($N_2O$) and Oxygen. * **Amnestic Effect:** Midazolam is the preferred ataractic for premedication due to its potent **anterograde amnesia** and rapid onset. * **Dissociative Anesthesia:** Distinct from ataractics, this is produced by **Ketamine**, where the patient appears awake but is unconscious and insensitive to pain.

Practice by Chapter

Preoperative Assessment Framework

Practice Questions

ASA Physical Status Classification

Practice Questions

Preoperative Laboratory Testing

Practice Questions

Cardiovascular Evaluation

Practice Questions

Pulmonary Evaluation

Practice Questions

Assessment of the Difficult Airway

Practice Questions

Medication Management

Practice Questions

NPO Guidelines

Practice Questions

Perioperative Anticoagulation Management

Practice Questions

Premedication

Practice Questions

Informed Consent

Practice Questions

Risk Stratification

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free