AI

Question 1

Explain the mechanism of action of norepinephrine.

Answer 1

Stimulates alpha‑1 (vasoconstriction ↑SVR ↑MAP) with some beta‑1 (↑contractility, mild ↑HR).

Question 2

How does vasopressin work differently from catecholamines?

Answer 2

Non‑catecholamine; acts on V1 receptors for vasoconstriction independent of adrenergic pathway—useful when adrenergic receptors are down‑regulated.

Question 3

What receptors does phenylephrine act on and what is the hemodynamic effect?

Answer 3

Pure alpha‑1 agonist → vasoconstriction ↑SVR/BP, reflex bradycardia ↓HR and CO.

Question 4

Difference between inotropes and vasopressors?

Answer 4

Inotropes increase contractility (e.g., dobutamine); vasopressors raise vascular tone/BP (e.g., norepinephrine).

Question 5

MAP dropping despite norepinephrine—next steps?

Answer 5

Check volume, correct acidosis, consider vasopressin/epinephrine, evaluate receptor desensitization.

Question 6

Add vasopressin vs titrate existing pressor?

Answer 6

If norepinephrine >0.1–0.2 mcg/kg/min, add vasopressin to lower catecholamine load via different pathway.

Question 7

Why avoid phenylephrine in cardiogenic shock?

Answer 7

Raises afterload without inotropy, worsening cardiac output.

Question 8

When use epinephrine over norepinephrine?

Answer 8

Anaphylaxis or when both strong inotropy and vasoconstriction needed (late septic or cardiogenic shock).

Question 9

Septic patient maxed out on norepi—next steps?

Answer 9

Add vasopressin, check volume, steroids, correct acidosis, consider epinephrine or methylene blue.

Question 10

Titrating pressors, patient becomes tachycardic—action?

Answer 10

Reassess; reduce beta‑active dose, switch to phenylephrine/vasopressin, treat pain, agitation, hypovolemia.

Question 11

Hypotensive with high SVR—give vasopressor?

Answer 11

No; use inotrope (dobutamine/milrinone) to improve output, not increase afterload.

Question 12

Effect of phenylephrine in hypovolemic patient?

Answer 12

Raises BP but worsens perfusion by increasing SVR without volume; can reduce tissue oxygenation.

Question 13

Can vasopressors be given peripherally? How?

Answer 13

Yes, short‑term; large proximal vein, close monitoring, convert to central line ASAP.

Question 14

Risks of extravasation and treatment?

Answer 14

Tissue necrosis; treat with phentolamine infiltration, elevate limb, surgical consult if severe.

Question 15

Protocol for titrating norepinephrine?

Answer 15

Start 0.01–0.05 mcg/kg/min, titrate to MAP > 65, monitor trends, avoid overshoot.

Question 16

What is the typical starting dose of norepinephrine?

Answer 16

0.01–0.05 mcg/kg/min, titrate to maintain MAP > 65 mmHg.

Question 17

What is the typical dose range for vasopressin in septic shock?

Answer 17

Fixed dose: 0.03 units/min—do not titrate.

Question 18

What is the dosing range for phenylephrine?

Answer 18

Start at 0.1–0.5 mcg/kg/min; may titrate based on MAP and HR.

Question 19

What is the starting dose of epinephrine for hypotension or shock?

Answer 19

0.01–0.1 mcg/kg/min; titrate to effect.

Question 20

How is dopamine dosed based on receptor activity?

Answer 20

Low (1–5 mcg/kg/min) = dopamine (renal), mid (5–10) = beta-1 (inotropy), high (>10) = alpha (vasoconstriction).

Question 21

What is the first-line vasopressor in ACLS for cardiac arrest?

Answer 21

Epinephrine 1 mg IV/IO every 3–5 minutes during CPR.

Question 22

What is the shockable rhythm in ACLS?

Answer 22

Ventricular fibrillation and pulseless ventricular tachycardia.

Question 23

What rhythms are non-shockable in ACLS?

Answer 23

Asystole and pulseless electrical activity (PEA).

Question 24

What is the correct dose of amiodarone in cardiac arrest?

Answer 24

First dose: 300 mg IV push; second dose: 150 mg if needed.

Question 25

What is the recommended rate and depth of compressions during CPR?

Answer 25

100–120 compressions/min at a depth of 2–2.4 inches (5–6 cm).

Question 26

What is Volume Control Assist-Control (VC-AC) mode?

Answer 26

The ventilator delivers a preset tidal volume with each breath; patient or ventilator can trigger breaths.

Question 27

What is Pressure Support Ventilation (PSV)?

Answer 27

Patient-initiated breaths are supported with a preset inspiratory pressure; no set rate or tidal volume.

Question 28

What is Pressure Control Ventilation (PCV)?

Answer 28

Ventilator delivers breaths with a set inspiratory pressure and time; tidal volume varies with lung compliance.

Question 29

What is SIMV (Synchronized Intermittent Mandatory Ventilation)?

Answer 29

Delivers set number of mandatory breaths synchronized with patient effort; spontaneous breaths are unassisted or pressure-supported.

Question 30

What does PEEP stand for and what is its purpose?

Answer 30

Positive End-Expiratory Pressure; prevents alveolar collapse, improves oxygenation.

Question 31

What is the typical tidal volume setting for a ventilated adult?

Answer 31

6–8 mL/kg of ideal body weight; lower (4–6 mL/kg) in ARDS.

Question 32

What does FiO2 mean and how is it adjusted?

Answer 32

Fraction of inspired oxygen; adjusted to maintain SpO2 > 90% or PaO2 > 60 mmHg.

Question 33

What is the risk of too high a tidal volume or pressure setting?

Answer 33

Barotrauma or volutrauma—can cause pneumothorax or lung injury.

Question 34

How does increasing PEEP affect oxygenation?

Answer 34

Increases mean airway pressure and alveolar recruitment → improves oxygenation.

Question 35

What is the purpose of a spontaneous breathing trial (SBT)?

Answer 35

Assess if patient can breathe without ventilator support—used to evaluate readiness for extubation.