A physician suggests that a ventilated patient needing immediate transport to CT scan and having severe pain be given IV fentanyl rather than morphine sulfate for pain management. One reason is:

• A. Rapid Administration Does Not Have Any Hemodynamic Consequences
• B. It Has a More Rapid Onset and a Shorter Duration of Action
• C. Weaning of a Continuous Infusion Is Never Needed Due to Its Short Half-Life
• D. It Is Not Likely to Cause Respiratory Depression

Answer: (B)

The key idea is choosing an analgesic with a rapid, controllable effect for a short, time-bound procedure. IV fentanyl fits this scenario because it provides quick pain relief within a minute or two and has a relatively short duration of action (roughly 30–60 minutes). That means you can rapidly titrate pain control for the moment of transport and the CT scan, and then have the effects wear off quickly enough to reassess or adjust without prolonged sedation or respiratory impact.

Fentanyl’s rapid onset and shorter duration make it easier to manage during a brief, high-stress event. Morphine, by comparison, takes longer to achieve full analgesia and lasts longer, which can complicate transport and post-imaging assessment. Also, fentanyl can provide potent analgesia with less histamine release than morphine, reducing some hemodynamic concerns, though it is not free of respiratory or cardiovascular effects.

It’s not accurate to say rapid administration has no hemodynamic consequences, nor that a short half-life eliminates the need to wean a continuous infusion, and fentanyl can still depress respiration—especially at higher doses.