N13 General anesthetics

Question 1

Propofol

Answer 1

• most frequently used for anesthesia induction
• effects mediated by GABAa Cl- channel potentiation (Like benzos)
• recovery is more complete, less hangover effects

Question 2

Midazolam

Answer 2

• short half-life
• brief therapeutic procedures
• mediated by GABAa
• rapidly reversed with flumazenil (blocks BZ1 and BZ2) does not reverse propofol

Question 3

Etomidate

Answer 3

• hypnotic but not analgesic
• GABAa
• minimal hemodynamic effects, good for cardiac pts (does not depress heart)

Question 4

Ketamine

Answer 4

“k-hole”
- signif analgesia, dissociative anesthesia (pt’s eyes remain open with slow nystagmic gaze”
- mech: blocking NMDA (glutamate) receptors similar to PCP
- minimal effects on respiration - useful in asthma and COPD pts.
- emergence rx - vivid, colorful dreams, hallucinations, out of body xp

Question 5

fentanyl

Answer 5

opoid - reach brain faster, 80-100x more portent than morephine.
- iv = short t1/2
- stimulates Mu receptors - Gi coupled that inhibit the release of sub-p and prevents propagation of pain signals
- used for postoperative analgesia
- reversed by naloxone