Complications in Anesthesia

Complications in Anesthesia Indian Medical PG Question 1: A patient was operated for right upper lobe resection. He was shifted to post awakening recovery after completion of surgery with vitals- BP 100/70 mm of Hg, HR - 94bpm, SPO2 100. After 2 hrs when he was assessed ,his vitals was BP 70/50 mm of Hg. HR-126 bpm ,SPO2 92 and surgical drain was filled with blood. Immediate re-exploration was planned. IV anaesthetic agent of choice -

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

Complications in Anesthesia Explanation: ***Ketamine*** - The patient is experiencing **hypovolemic shock** due to hemorrhage, characterized by **hypotension** (BP 70/50), **tachycardia** (HR 126), and **hypoxia** (SpO2 92). Ketamine is the preferred agent in this scenario due to its **sympathomimetic effects**, which help to **maintain hemodynamic stability** by increasing heart rate and systemic vascular resistance. - Unlike other intravenous anesthetics, ketamine typically **preserves pharyngeal and laryngeal reflexes** and causes minimal respiratory depression, which is advantageous in a critically ill patient. *Thiopentone* - This drug is a **barbiturate** known for its significant **myocardial depressant effects** and tendency to cause marked **vasodilation**, both of which would further exacerbate the patient's existing hypotension and shock state. - It also causes direct **respiratory depression** and abolished airway reflexes, making it unsuitable for a hemodynamically unstable patient. *Propofol* - Propofol is a potent **vasodilator** and **myocardial depressant**, leading to a dose-dependent decrease in blood pressure through reduction of systemic vascular resistance and cardiac output. - It lacks analgesic properties and can cause significant **respiratory depression** and apnea, which would be detrimental to a patient with compromised oxygen saturation. *Etomidate* - While etomidate is known for its **hemodynamic stability** and minimal impact on blood pressure, it causes **adrenocortical suppression** by inhibiting 11-beta-hydroxylase, which can be detrimental in a stressed patient requiring an adequate stress response. - It also has a high incidence of **myoclonus** and **postoperative nausea and vomiting**, which are undesirable in a patient requiring emergency re-exploration when other options with more beneficial effects are available.

Complications in Anesthesia Indian Medical PG Question 2: Which of the following inhalational anesthetic agents is known to cross the blood-brain barrier most effectively?

• A. Methoxyflurane
• B. Sevoflurane
• C. Desflurane (Correct Answer)
• D. Nitrous oxide

Complications in Anesthesia Explanation: ***Desflurane*** - **Desflurane** has a **low blood-gas partition coefficient (0.42)**, meaning it is poorly soluble in blood. - This low solubility facilitates its rapid uptake into the brain and quick elimination, making it cross the **blood-brain barrier** very effectively and leading to a rapid onset and offset of anesthesia. *Methoxyflurane* - **Methoxyflurane** has a **high blood-gas partition coefficient (12.0)**, leading to slow induction and emergence from anesthesia. - Its high solubility in blood means it poorly crosses the **blood-brain barrier** compared to less soluble agents. *Sevoflurane* - **Sevoflurane** has a **moderate blood-gas partition coefficient (0.69)**, allowing for relatively rapid induction and emergence, but not as rapid as desflurane. - While it effectively crosses the **blood-brain barrier**, its solubility is higher than desflurane, making it slightly less effective in this regard. *Nitrous oxide* - **Nitrous oxide** has a very low blood-gas partition coefficient (0.46), leading to an extremely rapid onset and offset. - However, its **low potency (high MAC)** means it cannot achieve deep anesthetic states on its own, and its primary mechanism involves displacement of nitrogen from air-filled cavities, which differs from direct BBB crossing for maintenance of anesthesia.

Complications in Anesthesia Indian Medical PG Question 3: All of the following are complications of epidural anaesthesia, EXCEPT:

• A. Urinary retention
• B. Total spinal analgesia
• C. Hypopnoea
• D. Hypertension (Correct Answer)

Complications in Anesthesia Explanation: ***Hypertension*** - Epidural anesthesia commonly causes **vasodilation** and a subsequent drop in **blood pressure** (hypotension), not hypertension, due to sympathetic blockade. - While hypertension can occur due to pain or anxiety during the procedure, it is not a direct physiological complication of the epidural anesthetic itself. *Urinary retention* - Epidural anesthesia can affect the nerves controlling the **bladder**, leading to temporary **urinary retention**. - This is a common complication, often requiring catheterization until the epidural wears off. *Total spinal analgesia* - This occurs if the epidural needle inadvertently punctures the **dura** and a large dose of local anesthetic is injected into the **subarachnoid space**. - It results in widespread **sensory and motor blockade**, potentially leading to respiratory arrest and hemodynamic collapse. *Hypopnoea* - High epidural blocks or accidental **intrathecal administration** can cause paralysis of **intercostal muscles** and the diaphragm. - This can lead to **respiratory depression** (hypopnoea) or even apnea, necessitating ventilatory support.

Complications in Anesthesia Indian Medical PG Question 4: While performing triage in response to a disaster emergency, commonly an internationally accepted four-colour code system is used. Which one among the following four-colour categories represents the highest priority for emergency response ?

• A. Green
• B. Red (Correct Answer)
• C. Black
• D. Yellow

Complications in Anesthesia Explanation: ***Red*** - The **red** category is assigned to patients with **immediate, life-threatening injuries** who have a high probability of survival with prompt medical intervention. - This color signifies the **highest priority** for medical treatment and transport to maximize their chances of survival. *Green* - The **green** category is for patients with **minor injuries** that are not life-threatening and can wait for medical attention. - These individuals are often referred to as walking wounded and can typically self-evacuate or wait for more critical patients to be treated. *Black* - The **black** category is reserved for patients who are either **deceased** or have injuries so severe that survival is unlikely, even with immediate medical care. - In a mass casualty situation, resources are generally not allocated to these individuals to prioritize those with a higher chance of survival. *Yellow* - The **yellow** category is for patients with **significant injuries** that are not immediately life-threatening but require definitive medical care within a few hours. - These patients are considered "delayed" and their treatment can be postponed until after red-category patients have been managed.

Complications in Anesthesia Indian Medical PG Question 5: Exposure to gases is a common hazard in industries. The gases can be classified as simple asphyxiants, chemical asphyxiants and anaesthetic gases. Which among the following are chemical asphyxiating gases ? 1. Carbon monoxide 2. Chloroform 3. Cyanide gas 4. Hydrogen Select the correct answer using the code given below :

• A. 2 and 4
• B. 1 and 3 (Correct Answer)
• C. 1 and 4
• D. 2 and 3

Complications in Anesthesia Explanation: ***1 and 3*** - Both **carbon monoxide** and **cyanide gas** are classic examples of chemical asphyxiants. - They interfere with the body's ability to utilize oxygen, leading to **cellular hypoxia** despite adequate tissue perfusion. *2 and 4* - **Chloroform** is an anesthetic and hepatotoxin, not primarily an asphyxiant. - **Hydrogen** is a simple asphyxiant but does not have the chemical asphyxiant properties of carbon monoxide or cyanide. *1 and 4* - While **carbon monoxide** is a chemical asphyxiant, **hydrogen** is a simple asphyxiant that displaces oxygen without directly interfering with cellular respiration. - The question implies a focus on gases that chemically interfere with oxygen utilization. *2 and 3* - **Cyanide gas** is an asphyxiant, but **chloroform** is an anesthetic and can cause central nervous system depression and organ toxicity. - Chloroform's mechanism of action is distinct from the cellular hypoxia caused by asphyxiants.

Complications in Anesthesia Flashcard 1 of 5

Question: What is a common post-anesthetic complication in patients with Duchenne muscular dystrophy?_____

Answer: Malignant hyperthermia

Complications in Anesthesia Flashcard 2 of 5

Question: Tuberculin syringe 1ml or insulin syringe _____units, without fixed needle x3 are one of the components of the anaphylaxis kit

Answer: 40

Complications in Anesthesia Flashcard 3 of 5

Question: _____ effect is the decrease in the partial pressure of the 2nd gas (leading to hypoxia) due to the rapid elimination of first gas during recovery from anesthesia

Answer: Finks

Complications in Anesthesia Flashcard 4 of 5

Question: _____G needles and swabs x3 are one of the components of the anaphylaxis kit

Answer: 24/25

Complications in Anesthesia Flashcard 5 of 5

Question: Propofol infusion syndrome is seen when the dose of propofol infusion is greater than _____ mg/kg/hour for 48 hours or longer

Answer: 4