IV Anesthetics- Sedatives/ Benzos & reversals Flashcards
what is precedex
Dexamdetomidine
Dexmedetomidine
class/ category
Adrenergic Agonist; Sedative, Analgesic
Dexmedetomidine
Uses-5
- MAC
- multimodal adjunct for general anesthesia
- anxiolysis
- analgesia
- ICU sedation for mechanically ventilated patients
Dexmedetomidine
MOA
Selective α2 adrenergic agonist (1620 α2:1 α1)
Dexmedetomidine
Dose: bolus and infusion
Bolus: 0.5-1 mcg/kg/min over 10 min
Infusion: 0.4-0.7 mcg/kg/hr
dexmedetomidine
Onset
Onset: 10-20 min (with loading dose)
Dexmedetomidine
Peak and duration
Peak: 15-25 min
Duration: 60-120 minutes
Dexmedetomidine
metabolism/ elimination
Hepatic
Dexmedetomidine
CV effects
-↓ BP; ↓ HR typically after loading dose (up to 40%)
-Transient ↑ BP possible, especially after loading dose
-Possible cardiac arrest (if cannot tolerate bradycardia or take other medications that cause bradycardia)
-Heart block
Dexmedetomidine
Pulm effects
-Minimal ventilatory depressant effects; likely not clinically significant
-↓ ventilatory response to hypoxia, CO2 response preserved
-May decrease upper airway patency with light to moderate sedation
Dexmedetomidine
CNS effects
- ↓ CBF ; ↓/↔ CMRO2
- ↔ ICP
- ↔/↓ CPP
- Autoregulation preserved
- Unable to produce EEG burst suppression or isoelectric EEG even at high doses, moderate EEG slowing, mimics normal sleep pattern on EEG
Dexmedetomidine
GI effects
nausea
What can Dexmedetomidine do to pt temperature
May promote perioperative hypothermia
T/F Precedex can cause xerostomia?
and what is xerostomia?
True (dry mouth)
What is not guarenteed because dexmedetomidine lacks these properties?
Can this be uses as a sole agent?
-Amnesia NOT guaranteed (lacks amnestic properties)
-Insufficient as a sole agent
Does precedex cause MH
NO, MH safe
What does precedex to do requirements of what type of agents?
Decreases requirements of IV and inhaled anesthetics
What is Versed
Midazolam
Midazolam
Class/ Category and MOA
-Class/Category: GABA agonist; Benzodiazepine
-Mechanism of Action: GABA agonist
Midazolam
Uses
Uses:
* Anterograde amnesia,
* preoperative anxiolysis,
* hypnosis,
* anticonvulsant;
* MAC
Versed
Onset, peak, duration
Onset: 30-60 sec
Peak: 2-3 min
Duration: 15-60 min
Midazolam
Active metabolites and metabolism
Active metabolites: 1-hydroxymidazolam (50% potency)
Metabolism: Hepatic
Versed
CV effects
-Minimal CV depression,
↔ CO
-Especially at induction doses (0.1-0.3 mg/kg IV): ↓ SVR → ↓ BP (may be pronounced with hypovolemia)
Midazolam
Premedication dose
Premedication: 0.02-0.04 mg/kg IV/IM, typically 2-5 mg IV
Midazolam
Sedation and Induction doses
Sedation: 0.01-0.1 mg/kg IV
Induction: 0.1-0.3 mg/kg IV
Midazolam
Pulm Effects
-Minimal ventilatory depressant effects
-Ventilatory depressant effects may be exaggerated with comorbidities (COPD), especially in the presence of other CNS depressants or with concurrent opioids
-Relaxes upper airway smooth muscle, may depress upper airway reflexes
Midazolam
CNS effects
-↓ CBF, ↓ CMRO2
-↓/↔ ICP
-↓/↔ CPP
-Dose-dependent CNS depression
-Maintains CO2 responsiveness
-Unable to produce EEG burst suppression or isoelectric EEG (ceiling effect)
Avoid versed in what conditions
2
-Avoid in pregnancy
-Avoid with acute porphyrias
Benzo reversal
Flumazenil
Midazolam does what to the requirement of which agents?
Decreases requirements of IV and inhaled anesthetics in a dose-dependent fashion
Diazepam does what to the requirement of which agents?
Decreases requirements of IV and inhaled anesthetics in a dose-dependent fashion
Lorazepam does what to the requirement of which agents?
Decreases requirements of IV and inhaled anesthetics in a dose-dependent fashion
midazolam causes what with what type of medications?
Synergistic effect with other CNS depressants
Diazepam causes what with what type of medications?
Synergistic effect with other CNS depressants
Lorazepam causes what with what type of medications?
Synergistic effect with other CNS depressants
What is Valium
Diazepam
Diazepam
Class/ category and MOA
Class/Category: GABA agonist; Benzodiazepine
Mechanism of Action: GABA agonist
Diazepam
Uses
Uses:
* Anterograde amnesia,
* preoperative anxiolysis,
* anticonvulsant;
* MAC
Diazepam
maintenance dose
Maintenance: 0.1 mg/kg as needed, may repeat every 10-15 min until seizures stop
Diazepam
Sedation and MAX dose
Sedation: 2 mg, titrated to effect
Max Dose: 30 mg
Diazepam
Onse, Peak, duration
Onset: 1-5 min
Peak: 15 min
Duration: 15-60 min
Diazepam
metabolism and active metabolites
Metabolism: Hepatic
Active metabolites: Desmethyldiazepam (return of drowsiness 6-8 hrs later), oxazepam, temazepam
Valium
CV effects
-Minimal ↓ BP, ↓ CO, ↓ SVR
-Especially at induction doses: ↓ SVR → ↓ BP (may be pronounced with hypovolemia)
Diazepam
Pulm effects
-Minimal ventilatory depressant effects; may depress upper airway reflexes
-Effects may be exaggerated with comorbidities (COPD), especially in the presence of other CNS depressants or with concurrent opioids
-↓ Vt, may result in apnea
-↑ PaCO2 at higher doses
Diazepam
CNS effects
6
-↓ CBF, ↓ CMRO2
-↓ ICP
-↓/↔ CPP
-Dose-dependent CNS depression
-Maintains CO2 responsiveness
-Unable to produce EEG burst suppression or isoelectric EEG (ceiling effect)
What affect does diazepam cause with what other medication?
Potentiates ventilatory depressant effects of opioids
Avoid Diazepam in what two conditions and what side effect could it cause?
-Avoid in pregnancy: Associated with cleft lip with or without cleft palate
-Avoid with acute porphyrias
What affect does Lorazepam cause with what other medication?
Potentiates ventilatory depressant effects of opioids
What is Ativan
Lorazepam
Lorazepam
Class/ category and MOA
-Class/Category: GABA agonist; Benzodiazepine
MOA: GABA agonist
Lorazepam
uses
Uses: Anterograde amnesia, preoperative anxiolysis, anticonvulsant
Lorazepam
dose
Bolus: 0.5-4 mg (0.03-0.1 mg/kg)
Lorazepam
Onset, Peak, duration
Onset: 1-2 min
Peak: 20-30 min
Duration: 6-10 hrs
Lorazepam
metabolism and elimination
Metabolism: Hepatic
Elimination: Renal
Lorazepam
CV effects
-Minimal ↓ BP, ↓ CO, ↓ SVR
-Especially at induction doses: ↓ SVR → ↓ BP (may be pronounced with hypovolemia
Lorazepam
Pulm effects
-Minimal ventilatory depressant effects; may depress upper airway reflexes
-Effects may be exaggerated with comorbidities (COPD), especially in the presence of other CNS depressants or with concurrent opioids
-↓ Vt, may result in apnea
-↑ PaCO2 at higher doses
Lorazepam
CNS effects
-↓ CBF, ↓ CMRO2
-↓ ICP
-↓/↔ CPP
-Dose-dependent CNS depression
-Maintains CO2 responsiveness
-Unable to produce EEG burst suppression or isoelectric EEG (ceiling effect)
avoid lorazepam in what two conditions
Avoid in pregnancy
Avoid with acute porphyrias
Remimazolam
Class/ category, uses, MOA
Class/Category: GABA agonist; Benzodiazepine
Uses: Procedural sedation
Mechanism of Action: GABA agonist
Remimazolam
Initial and subsqeuent doses
Initial: 5 mg IV over 1 min
Subsequent: 2.5 mg IV over 15 sec, every 2+ minutes as needed
what is Byfavo
Remimazolam
Remimazolam
onset, peak, duration
Onset: 1 min
Peak: 3-3.5 min
Duration: 11-14 min
Remimazolam
metabolism
Metabolism: Plasma and Non-specific tissue esterases
Remimazolam
CV effects
↓ BP or ↑ BP
↓ HR
Remimazolam
Pulm effects
↓ SpO2
↑ RR
Remimazolam
CNS and GI effects
CNS:Headache
GI: Nausea
what patient population would you avoid remimazolam in?
Avoid in patients with hypersensitivity to dextran 40
What is Romazicon
Flumazenil
Flumazenil
Class/ category and MOA
Class/Category: GABA antagonist; Competitive/reversible benzodiazepine antagonist
Mechanism of Action: GABA antagonist
Flumazenil
uses
Uses: Reversal of benzodiazepine sedative effects, benzodiazepine overdose, delayed emergence
Flumazenil
bolus and infustion dose
Bolus: 0.2 mg, repeat doses 0.1 mg every 60 sec, to total 1 mg; titrated to desired level of consciousness
Infusion: 0.1-0.4 mg/hr
Flumazenil
onest, peak, duration
Onset: 1-2 min
Peak: 1-3 min
Duration: 45-90 min
flumazenil
metabolism
hepatic
Patients usually respond to what dose of flumazenil
0.6-1mg
Doses of flumazenil rarely exceed what dose for what type of use?
Doses rarely exceed:
-1 mg for reversal of midazolam sedation
-5 mg for reversal of ventilatory depressant effects
-3 mg for benzodiazepine overdose
If you require more than what dose of flumazenil what should you suspect
If > 5 mg required in attempt at reversal, suspect other contributing agents
what are contraindidcations or population to avoid giving flumazenil to?
-Contraindication: Benzodiazepine dependent patients
-Avoid if known history of seizures – could precipitate withdrawal seizures
what effect could you see with flumazenil for what medication and for how long?
Be aware for potential resedation effects from midazolam for up to 2 hrs
