Postoperative Care Practice Questions

Q: Which of the following complications is most likely to occur after receiving several units of blood transfusion?

Metabolic alkalosis. **Explanation:** The correct answer is **Metabolic Alkalosis**. This occurs primarily due to the metabolism of **sodium citrate**, which is used as an anticoagulant in stored blood bags. 1. **Mechanism of Correct Answer:** Each unit of whole blood or packed red blood cells contains a significant amount of citrate. Once transfused, the liver metabolizes citrate into **bicarbonate (HCO₃⁻)**. In massive transfusions (typically defined as >10 units in 24 hours or >4 units in 1 hour), the sudden load of bicarbonate exceeds the kidney's excretory capacity, leading to an increase in blood pH and metabolic alkalosis. 2. **Why Incorrect Options are Wrong:** * **Metabolic Acidosis:** While stored blood is slightly acidic due to the accumulation of lactic acid and pyruvic acid over time, this is transient. Once transfused, the metabolic conversion of citrate to bicarbonate quickly shifts the balance toward alkalosis. Acidosis is only seen in the initial phase of a massive transfusion or in patients with severe liver failure who cannot metabolize citrate. * **Respiratory Alkalosis/Acidosis:** These are primary disorders of ventilation (CO₂ elimination). Blood transfusion does not directly affect the respiratory drive or CO₂ exchange in a way that would predictably cause these conditions as a primary metabolic consequence. **High-Yield Clinical Pearls for NEET-PG:** * **Citrate Toxicity:** Rapid transfusion can lead to hypocalcemia because citrate chelates ionized calcium. Always monitor for signs like prolonged QT interval or tetany. * **Potassium Shift:** Stored blood contains high extracellular potassium (due to RBC lysis). However, post-transfusion, as the cells become active and the alkalosis persists, **hypokalemia** is more common than hyperkalemia. * **Hypothermia:** Transfusing cold blood can shift the oxyhemoglobin dissociation curve to the left, further complicating tissue oxygen delivery.

Q: Which of the following does not cause vomiting in a post-operative patient?

Acetaminophen. **Explanation:** Postoperative Nausea and Vomiting (PONV) is a common complication influenced by patient factors, surgical type, and anesthetic agents. **Why Acetaminophen is the Correct Answer:** Acetaminophen (Paracetamol) is a non-opioid analgesic that acts primarily on the central nervous system to inhibit prostaglandin synthesis. Unlike opioids or volatile anesthetics, it has **no emetogenic potential**. In fact, its use is a key component of "Opioid-Sparing Analgesia" in ERAS (Enhanced Recovery After Surgery) protocols, specifically to **reduce** the incidence of PONV by decreasing the requirement for emetogenic opioids. **Analysis of Incorrect Options:** * **Ingested Blood (Option A):** Blood is a potent gastric irritant. In surgeries involving the oropharynx (e.g., tonsillectomy or dental surgery), swallowed blood triggers the chemoreceptors in the stomach, leading to postoperative vomiting. * **Nitrous Oxide (N2O) (Option B):** N2O is known to increase PONV through multiple mechanisms: middle ear pressure changes, sympathetic stimulation, and activation of the dopaminergic system in the CTZ (Chemoreceptor Trigger Zone). * **Opioids (Option D):** Opioids are a leading cause of PONV. They directly stimulate the CTZ in the area postrema of the medulla, increase vestibular sensitivity, and delay gastric emptying. **High-Yield Clinical Pearls for NEET-PG:** 1. **Apfel Score:** The most validated tool to predict PONV risk. Factors include: Female gender, Non-smoker status, History of PONV/Motion sickness, and Postoperative opioid use. 2. **Emetogenic Anesthetics:** Volatile inhalational agents (Isoflurane, Sevoflurane) and N2O are highly emetogenic. **Propofol** is the only anesthetic with significant **anti-emetic** properties. 3. **Gold Standard Prophylaxis:** 5-HT3 receptor antagonists (e.g., Ondansetron) are the first-line treatment for PONV.

Q: Which of the following is the most significant risk factor for postoperative nausea and vomiting?

Female gender. **Explanation:** Postoperative Nausea and Vomiting (PONV) is a common complication affecting approximately 30% of surgical patients. The most widely accepted tool for predicting risk is the **Apfel Simplified Risk Score**, which identifies four independent predictors. **1. Why Female Gender is Correct:** Female gender is the **strongest independent risk factor** for PONV. Adult females are approximately three times more likely to experience PONV than males. This is attributed to hormonal influences, specifically the fluctuations in estrogen and progesterone levels which sensitize the chemoreceptor trigger zone (CTZ) and the vomiting center. **2. Analysis of Incorrect Options:** * **Smoking:** Interestingly, **non-smoking status** is the risk factor. Smoking actually has a protective effect against PONV, likely due to the induction of hepatic enzymes or desensitization of dopamine receptors. * **Age over 60 years:** PONV is more common in **younger adults**. The incidence actually decreases as age increases; it is relatively rare in the elderly. * **Surgery on the breast:** While certain surgeries (laparoscopic, gynecological, breast, and strabismus surgery) are associated with higher PONV rates, **patient-related factors** (like gender) are statistically more significant predictors than the type of surgery itself. **Clinical Pearls for NEET-PG:** * **Apfel Score Criteria:** 1) Female gender, 2) Non-smoker, 3) History of PONV or motion sickness, 4) Use of postoperative opioids. * **Risk Probability:** 1 factor = 20%, 2 = 40%, 3 = 60%, 4 = 80% risk. * **Gold Standard Prophylaxis:** Combination therapy (e.g., 5-HT3 antagonists like Ondansetron + Dexamethasone) is superior to monotherapy for high-risk patients. * **Anesthetic Technique:** Using Propofol for Total Intravenous Anesthesia (TIVA) significantly reduces PONV risk compared to volatile anesthetics and nitrous oxide.

Q: Emergence delirium is associated with –

Ketamine. ***Ketamine*** - **Ketamine**, an N-methyl-D-aspartate (NMDA) receptor antagonist, is known to cause **emergent delirium** or **psychotic reactions** during recovery from anesthesia due to its dissociative properties. - This adverse effect is more common in adults and can manifest as **hallucinations**, **vivid dreams**, and **confusion**, particularly when used as a sole anesthetic agent. *Halothane* - **Halothane** is an inhalational anesthetic that was associated with relatively slow emergence, but not typically with **delirium** as a prominent feature. - Its primary concern was **hepatotoxicity** (halothane hepatitis) and **malignant hyperthermia**, rather than emergence delirium. *Pentothal sodium* - **Pentothal sodium** (thiopental) is a short-acting barbiturate used for induction of anesthesia, known for rapid onset and offset. - While it can cause some **post-operative drowsiness**, it is not primarily associated with **emergent delirium**; instead, it provides a smooth and calm recovery. *Droperidol* - **Droperidol** is an antipsychotic and antiemetic agent often used to prevent post-operative nausea and vomiting, and can cause **sedation**. - It is known to **reduce** the incidence of emergence delirium caused by other agents, rather than causing it itself.

Q: In the immediate post operative period the common cause of respiratory insufficiency could be because of the following, except -

Mild Hypovolemia. ***Mild Hypovolemia*** - While significant **hypovolemia** can lead to systemic complications, *mild hypovolemia* itself does not directly cause *respiratory insufficiency* in the immediate postoperative period without other complicating factors. - Hypovolemia primarily affects **cardiovascular stability** and tissue perfusion, not directly the mechanics or drive of respiration unless it progresses to **shock**. *Residual effect of muscle relaxant* - **Residual neuromuscular blockade** can lead to *diaphragmatic weakness* and impaired accessory muscle function, causing insufficient ventilation and respiratory distress. - This is a common cause of *postoperative respiratory insufficiency*, especially if reversal agents are inadequate or not administered. *Overdose of narcotic analgesic* - **Narcotic overdose** depresses the *respiratory drive* in the brainstem, leading to decreased respiratory rate and depth, which can result in **hypoventilation** and *respiratory insufficiency*. - This is a significant concern in the immediate postoperative period due to pain management requirements. *Myocardial infarction* - A *myocardial infarction* can lead to **cardiogenic pulmonary edema** due to impaired cardiac function, resulting in fluid accumulation in the lungs and *respiratory insufficiency*. - Postoperative myocardial infarction is a serious complication that directly impacts respiratory function through its effect on **pulmonary hemodynamics**.

Q: A postoperative patient with pH 7.25, MAP (mean arterial pressure) 60 mm Hg is treated with?

Fluid therapy with CVP monitoring. ***Fluid therapy with CVP monitoring*** - The patient's **MAP of 60 mmHg** indicates **hypotension** and potential **hypovolemic shock**, while pH 7.25 suggests **acidosis**, which could be metabolic due to poor perfusion. Initial treatment should focus on **restoring circulating volume** to improve blood pressure and organ perfusion. - **Central venous pressure (CVP) monitoring** is crucial to guide fluid resuscitation. It helps assess the patient's fluid status and ensures that enough fluid is given to improve cardiac output without causing fluid overload, especially in a severely ill patient. *Only normal saline* - While normal saline is used for fluid resuscitation, simply stating "only normal saline" is insufficient because it doesn't address the **critical need for monitoring** to guide treatment. - The amount and rate of fluid administration need to be carefully controlled based on the patient's response and hemodynamic parameters. *Fluid restriction* - **Fluid restriction** would be contraindicated in this patient because the **low MAP** suggests **hypovolemia or cardiogenic shock**, requiring fluid repletion, not restriction. - Restricting fluids could further worsen hypotension and organ hypoperfusion, leading to increased acidosis and organ damage. *I.V. sodium bicarbonate* - Administering **I.V. sodium bicarbonate** to correct acidosis without addressing the underlying cause of hypotension and poor perfusion is generally not recommended. - The acidosis (pH 7.25) is likely due to **poor tissue oxygenation and lactic acid production** from inadequate blood flow; correcting this with fluids will resolve the acidosis.

Q: A 25-year-old overweight female was given fentanyl-pancuronium anesthesia for surgery. After surgery and extubation, she was observed to have limited movement of the upper body and chest wall in the recovery room. She was conscious and alert, but voluntary respiratory effort was limited. Her blood pressure and heart rate were normal. The likely diagnosis is:

Incomplete reversal of pancuronium. ***Incomplete reversal of pancuronium*** - **Pancuronium** is a **nondepolarizing neuromuscular blocker** that causes muscle paralysis; incomplete reversal would lead to residual weakness and limited movement, especially of the respiratory muscles. - The patient is **conscious and alert** but has limited voluntary respiratory effort and upper body movement, consistent with residual neuromuscular blockade rather than central respiratory depression. *Respiratory depression* - While opioids like fentanyl can cause respiratory depression, the patient being **conscious and alert** makes primary central respiratory depression less likely. - **Fentanyl-induced respiratory depression** would typically involve a decreased respiratory rate and depth, often with an altered mental status, which is not described. *Pulmonary embolism* - A **pulmonary embolism** would typically present with **dyspnea, tachypnea, tachycardia**, and potentially hypoxemia, which are not mentioned in this scenario. - The patient's **normal blood pressure and heart rate** make an acute, significant pulmonary embolism less probable. *Fentanyl-induced chest wall rigidity* - **Fentanyl-induced chest wall rigidity** ("woody chest syndrome") occurs *during* rapid intravenous administration or high doses of opioids, making ventilation difficult. - This typically occurs **intraoperatively** or immediately post-administration, not in the recovery room after extubation when a patient is conscious and attempting voluntary breathing.

Q: The following are used for treatment of postoperative nausea and vomiting following squint surgery in children except:-

Ketamine. ***Ketamine*** - **Ketamine** is an anesthetic and analgesic agent that is known to **increase the incidence of postoperative nausea and vomiting (PONV)**, particularly at higher doses, making it unsuitable for preventing PONV. - Its mechanism of action can stimulate the **chemoreceptor trigger zone** and **vestibular system**, contributing to emetogenic effects. *Ondansetron* - **Ondansetron** is a **serotonin 5-HT3 receptor antagonist** and is a first-line drug for the prevention and treatment of PONV in both adults and children. - It effectively blocks serotonin in the gastrointestinal tract and the **medulla oblongata**, reducing nausea and vomiting. *Propofol* - **Propofol** is an intravenous anesthetic that has **antiemetic properties**, making it useful for reducing PONV when used as part of the anesthetic regimen or as a sub-hypnotic bolus. - Its antiemetic effect is thought to be mediated through **dopamine receptor blockade** and action on the **GABAergic system**. *Dexamethasone* - **Dexamethasone** is a **corticosteroid** with significant antiemetic properties, commonly used as an adjunct for PONV prevention. - It is believed to act by inhibiting **prostaglandin synthesis** and reducing inflammation, thereby modulating pathways involved in nausea and vomiting.

Q: Which of the following agents is used for the treatment of post operative shivering?

Pethidine. ***Pethidine*** - **Pethidine (meperidine)** is a **synthetic opioid** known for its **mu-receptor agonism** and weak anticholinergic properties, making it effective in treating **post-operative shivering**. - Its mechanism in reducing shivering is thought to involve modulation of the **thermoregulatory center** in the hypothalamus. *Atropine* - **Atropine** is an **anticholinergic drug** that primarily blocks muscarinic acetylcholine receptors, leading to effects like increased heart rate and decreased secretions. - It does not directly act on the thermoregulatory centers or muscle activity responsible for shivering. *Thiopentone* - **Thiopentone** is a **barbiturate** used as an intravenous anesthetic, primarily for induction of anesthesia. - While it has CNS depressant effects, it is not indicated or effective for the specific treatment of post-operative shivering. *Suxamethonium* - **Suxamethonium (succinylcholine)** is a **depolarizing neuromuscular blocker** used to induce muscle paralysis, typically for intubation. - It would prevent shivering by paralyzing skeletal muscles, but this is a dangerous and inappropriate treatment for shivering due to its profound respiratory depressant effects.

Question 1

A patient who underwent surgery under general anesthesia without intraoperative complications complains of respiratory difficulty and low PO2 postoperatively. The patient is unable to lift their head or legs. What is the most likely cause?

Accepted Answer

Prolonged action of muscle relaxant

Answer

Respiratory acidosis

Answer

Pulmonary embolism

Answer

Fentanyl-induced chest rigidity

Question 2

Which of the following complications is most likely to occur after receiving several units of blood transfusion?

Accepted Answer

Metabolic alkalosis

Answer

Metabolic acidosis

Answer

Respiratory alkalosis

Answer

Respiratory acidosis

Question 3

Which of the following does not cause vomiting in a post-operative patient?

Accepted Answer

Acetaminophen

Answer

Ingested blood

Answer

N2O

Answer

Opioids

Question 4

Which of the following is the most significant risk factor for postoperative nausea and vomiting?

Accepted Answer

Female gender

Answer

Smoking

Answer

Age over 60 years

Answer

Surgery on the breast

Question 5

Emergence delirium is associated with –

Accepted Answer

Ketamine

Answer

Halothane

Answer

Pentothal sodium

Answer

Droperidol

Question 6

In the immediate post operative period the common cause of respiratory insufficiency could be because of the following, except -

Accepted Answer

Mild Hypovolemia

Answer

Residual effect of muscle relaxant

Answer

Overdose of narcotic analgesic

Answer

Myocardial infarction

Question 7

A postoperative patient with pH 7.25, MAP (mean arterial pressure) 60 mm Hg is treated with?

Accepted Answer

Fluid therapy with CVP monitoring

Answer

Only normal saline

Answer

fluid restriction

Answer

I.V. sodium bicarbonate

Question 8

A 25-year-old overweight female was given fentanyl-pancuronium anesthesia for surgery. After surgery and extubation, she was observed to have limited movement of the upper body and chest wall in the recovery room. She was conscious and alert, but voluntary respiratory effort was limited. Her blood pressure and heart rate were normal. The likely diagnosis is:

Accepted Answer

Incomplete reversal of pancuronium

Answer

Respiratory depression

Answer

Pulmonary embolism

Answer

Fentanyl-induced chest wall rigidity

Question 9

The following are used for treatment of postoperative nausea and vomiting following squint surgery in children except:-

Accepted Answer

Ketamine

Answer

Ondansetron

Answer

Propofol

Answer

Dexamethasone

Question 10

Which of the following agents is used for the treatment of post operative shivering?

Accepted Answer

Pethidine

Answer

Atropine

Answer

Thiopentone

Answer

Suxamethonium

Postoperative Care — MCQs

Postoperative Care — MCQs

On this page

Practice by Chapter

Want unlimited practice?