reversal of benzo and opioid Flashcards
Benzodiazepine antagonist
Flumazenil (Romazicon)
MOA of flumazenil - romazicon
Competes with benzodiazepines for the benzodiazepine receptor sites on GABA receptors
Flumazenil (Romazicon) reverses [if given right]
the respiratory depressant effect of benzodiazepines
you have a pt that has exhaled all volatiles but is still showing signs of delayed emergence, what are you going to give?
flumazenil first then narcan
the Reversal of benzodiazepine effects from Flumazenil is buffered by
the weak agonist effect
Do NOT see these effects with flumazenil admin
Acute anxiety, stress response
Hypertension, tachycardia
Could see this effect from flumazenil admin
Withdrawal seizures for those on sz. treatment
what is the initial dose and how do you dose romazicon after intial?
initial - 0.2 mg IV then 0.1 mg IV every 60 seconds up to 1 mg
onset of flumazenil?
2 minutes [give it time to work before redosing]
duration of flumazenil?
30-60 minutes
amount of flumazenil you need to give to decrease sedation?
0.3-0.6 mg
amount of flumazenil you need to give to abolish benzo effect
0.5-1 mg
important thing to note about redosing flumazenil and narcan?
both have shorter duration than drug trying to reverse so tell RN that you had to give it so they are aware
what receptors does narcan effect more
mu more than kappa and delta
competitive opioid antagonist
naloxone - narcan
MOA of narcan
The attraction of naloxone for the receptor displaces the opioid from the receptor. The antagonist then binds with the receptor and inactivates it.
Clinical indications for the use of naloxone (4)
- Opioid overdose – deliberate or mistaken
- Postoperative ventilatory depression due to opioids
- Neonatal ventilatory depression due to maternal opioids (10 mcg/kg q 2 minutes)
- Adverse effects of spinal and epidural opioids
Dose of narcan
0.5-1 mcg/kg (35-70 mcg) q 3-5 min
what do you need to do in order to make narcan easier to give?
Dilute 0.4 mg/ml into 10 cc to get 40 mcg/ml (0.04 mg/ml)
onset and duration of naloxone?
onset - 1-3 mins
duration - 30 to 45 mins
metabolism of narcan
liver
what is the weird effect that narcan can have and why?
Acute pulmonary edema can be caused by the increase in pressure [sympathetic stimulation] and increased permeability of pulmonary capillaries.
Cardiovascular effects naloxone?
Sympathetic stimulation - PAIN
Tachycardia, ventricular irritability (V fib)
Hypertension
Related to speed and extent of reversal
CNS effects narcan?
Nausea and vomiting (speed, dose)
Return of airway reflexes which is good but can be bad if it causes laryngospasm
does narcan cross placenta?
YES may cause withdrawal symptoms if opioid-abusing mother
what can narcan precipitate in pts who appear normal on opioids?
withdrawals [aka abstinence syndrome]
What pt populations should you be careful or avoid narcan with?
Critically ill Coronary artery disease Preexisting lung disease Congestive heart failure Cardiac surgery Opioid dependence *sympathetic stimulation*
Central nervous system stimulant
doxapram - dopram
MOA doxapram
Stimulates hypoxic drive via the activation of the chemoreceptors in the carotid bodies (1 mg/kg = PaO2 of 38 mm Hg)
basically tricks the body into thinking we need to blow off some CO2
doxapram Produces an increase
tidal volume and RR. will see an increase in minute vent r/t the increase in tidal volume
Clinical indications for doxapram
- delayed emergence r/t not being able to get volatile out of lungs bc pt isn’t breathing
- COPD
- vent depression and CNS depression due to other meds
what two examples of patients are appropriate for doxapram use?
rigid bronchoscopy
airway case with high prop infusion that you can’t give NMB to so you need to make them breath
dose of doxapram?
0.5-1 mg/kg (max 4 mg/kg)
onset
duration
metabolism of doxapram
Onset: 1 minute
Duration: 5-10 minutes
Metabolism: primarily in the liver
CNS effects of doxapram
- Stimulates hypoxic drive due to activation of chemoreceptors in the carotid
- Mental status changes like confusion, dizziness, seizures (20-40X dose)
- Increased sympathetic outflow (increase HR, BP)
- Vomiting
- Increased body temperature
Respiratory effects of doxapram
- Increases minute volume by increasing tidal volume and slightly increasing respiratory rate
- Increases oxygen consumption
- Wheezing - bronchoconstriction
- Tachypnea
cards effects of doxapram?
Increased sympathetic stimulation
Hypertension
Tachycardia
Cardiac dysrhythmias