Opioids - the drugs Flashcards
drugs in the order of onset
Fast:
Alfentanil, Remifentanil: 1-3 min (≈ 1.1 - 1.4 min to equilibrate with the brain)
Semi-fast:
Fentanyl ≈ 1-2 min (≈ 6.8 min to equilibrate with the brain)
Sufentanil 1-3 min (≈ 6.2 min to equilibrate with the brain)
Meperidine <5 min
Slow
Morphine ? (peak 15-30 min)
Hydromorphone <30 min
tetrazole fentanyl derivative
alfentanil
can cause seizure
Meperidine (Demerol)
normeperidine, the active metabolite, is long acting (3 days) and half as potent; redosing & stacking doses puts pts at risk for seizures
Alfentanil contraindication
Parkinson’s - drug decreases dopaminergic transmission
increased ICP
use with caustion in asthma, head injury, drug dependency, respiratory conditions
opioids in the order of non-ionized %
Meperidine 7%
Fentanyl 8.5%
Sufentanil 20%
Morphine 23%
Remifentanil 58%
Alfentanil 89%
oipoid that has some myocardial depression
Meperidine (Demerol)
drug that has more sedation but less euphoria than morhine
hydromorphone
Slows EEG
Alfentanil
no effect on HR or MAP
Alfentanil
opioids in the order of Vd
Low
Alfentanil 0.4 L/kg (27 L)
Remifentanil 0.4 L/kg (30 L)
High
Sufentanil 3 L/kg (123 L)
Morphine 4 L/kg (224 L)
Meperidine 4 L/kg (305 L)
Fentanyl 4 L/kg (335 L)
order of potency - with relative potencies
(compared with MSO4)
- Sufentanyl 1000 X MSO4
- Remifentanyl 100-150 X MSO4
- Fentanyl 100 X MSO4
- Alfentanyl 10-20 X MSO4
- Dilaudid (hydromorphone) 5 X MSO4
- Morphine (MSO4)
- Demerol 1/10 X MSO4
metabolized by the liver and small intestine
Sufentanil
opioids in the order of protein binding
Hydromorphone 20%
Morphine 35%
Meperidine 50-70%
Fentanyl 84%
Remifentanil 66-92%
Alfentanil 92%
Sufentanil 93%
Has muscarinic effect
Meperidine (Demerol)
due to atropine like structure
hydromorphone contraindications
gi obstruction
asthma
hypersensitivity
severe resp depression
Remifentanil - metabolism, Vd, PB
metabolism: nonspecific plasma and tissue esterases (not pseudocholinesterases -> not affected by cholinesterases deficiency)
Vd = 0.3-0.5L/kg (small)
PB: 66-93%