Pharmacology
Which intravenous anesthetic agent causes both anesthesia and amnesia but has no analgesic properties?
Propofol
What muscle is primarily responsible for inspiration at rest?
The diaphragm
What is the main purpose of preoxygenation before induction?
To increase oxygen reserve by replacing nitrogen in the lungs with oxygen
What is the target oxygen saturation (SpO₂) for most ICU patients?
92–96 %
What is the first-line pharmacologic treatment for neuropathic pain?
Gabapentin or pregabalin
What is the mechanism of action of dexmedetomidine?
α₂-adrenergic agonist acting in the locus coeruleus
What happens to intrathoracic pressure during spontaneous inspiration?
It becomes more negative
What does the abbreviation ASA stand for in anesthesia classification?
American Society of Anesthesiologists
What is the first-line vasopressor in septic shock?
Norepinephrine
Which receptor subtype mediates the analgesic effects of opioids?
μ (mu) opioid receptor
Which opioid is preferred in renal failure due to inactive metabolites?
Fentanyl
Which nerve provides motor innervation to the diaphragm? And from which spinal roots does it emerge?
Phrenic nerve (C3–C5)
What drug is most commonly used for rapid sequence induction?
Succinylcholine
What is the normal range of mean arterial pressure (MAP) that ensures adequate organ perfusion?
70–100 mm Hg
What is the mechanism of action of ketamine in pain control?
NMDA receptor antagonism
Which volatile anesthetic is least metabolized by the liver?
Desflurane
Which lung is more likely to receive a foreign body aspiration in an upright patient?
The right lung
During spinal anesthesia, a patient develops severe hypotension and bradycardia — what is the main cause?
Sympathetic blockade causing vasodilation and decreased venous return
What’s the most accurate method for confirming endotracheal tube placement in the ICU?
Continuous waveform capnography (presence of CO₂)
In an epidural infusion, what is the main advantage of adding clonidine or dexmedetomidine to local anesthetics?
Prolongs analgesia and provides opioid-sparing effect
Name the neuromuscular blocker that is metabolized by Hofmann elimination and ester hydrolysis, independent of renal or hepatic function.
Cisatracurium
What is the normal resting membrane potential of a skeletal muscle cell in millivolts?
–90 mV
Which inhalational anesthetic agent is preferred for patients with asthma because it causes bronchodilation?
Sevoflurane
What type of shock is characterized by high cardiac output and low systemic vascular resistance?
Distributive shock (e.g., septic shock)
What is the main risk of bilateral intrascalene nerve block?
Bilateral phrenic nerve paralysis causing respiratory arrest.