General Anesthetics Flashcards
General Anesthetics Vs Local Anesthetics
General anesthetics are drugs that produce
unconsciousness and a lack of responsiveness to all
painful stimuli (Ketamine)
Local anesthetics do not reduce consciousness,
and they blunt pain only in a limited area
(Novocain)
Two main groups of anesthetics and facilitate what procedures?
Two main groups
• Inhalation anesthetics
• Intravenous anesthetics
Used to facilitate certain procedures
Endoscopy, urologic procedures, radiation therapy,
electroconvulsive therapy, transbronchial biopsy, and
various cardiologic procedures
What are IV Anesthetics
Short‐acting barbiturates (thiobarbiturates) • Benzodiazepines • Propofol • Etomidate • Ketamine
Benzodiazepines induce what?
When administered in large doses, benzodiazepines
produce unconsciousness and amnesia
Diazepam, lorazepam and midazolam can all be given IV
to induce amnesia
Benzos potentiate actions of gamma‐amino butyric acid
(GABA) which is the primary inhibitory neurotransmitter
in the CNS
Benzodiazepines V Barbiturates
Both “work” at GABA
• Barbiturates less used now due to abuse (safety?)
• Similar risks
Diazepam
Induction with intravenous diazepam [Valium]
• Unconsciousness within 1 minute
• Very little muscle relaxation
Generic name: Diazepam • Trade name: Valium • Classification: Benzodiazepine, skeletal muscle relaxant, amnestic, anticonvulsant, sedative‐hypnotic • Indications: 1. Status epilepticus / seizures 2. Skeletal muscle relaxation 3. Severely anxious or agitated patients 4. Cocaine overdose
Contraindications:
1. Hypersensitivity to any benzodiazepine
2. Acute narrow angle glaucoma
• Dose:
1. Adult: 2.5 – 5 mg IV/IO prn depending on condition
2. Pediatric: 0.1 ‐ 0.3 mg/kg slow IV or 0.3 mg/kg rectally to total
of 5 mg in child less than 5 years, IO mg if > 5 yrs
Midazolam
Unconsciousness within 80 seconds
• Can cause dangerous cardiorespiratory effects
Generic name: Midazolam • Trade name: Versed • Classification: Benzodiazepine, skeletal muscle relaxant, amnestic, anticonvulsant, sedative‐hypnotic • Indications: 1. Active seizure 2. Combative behavior 3. Maintenance of paralysis/sedation 4. Procedural sedation
Contraindications:
- Hypersensitivity
- Myasthenia gravis
- Hypotension (< 100mmHg)
Dose: Adult
1. Seizure – 10 mg IM or 5 mg SIVP/IO – total maximum of 20mg
- Combative behavior – 5 mg SIVP or 10 mg IM, total max of 20mg
- Maintenance of paralysis/sedation – 2.5 mg SIVP/IO q 10
minutes prn - Procedural sedation – 0.05 mg/kg SIVP to a single max dose of 2.5 mg, do not repeat
Dose: Pediatric
1. Seizure – 0.2 mg/kg IM/Intranasal to a single max dose
of 10 mg, 0.1 mg/kg SIVP.IO to a single max dose of 5mg
- Maintenance of paralysis/sedation – 0.05 mg/kg SIVP/IO
to a single max dose of 2.5 mg
Lorazepam
Generic name: Lorazepam
• Trade name: Ativan
• Classification: Benzodiazepine, skeletal muscle relaxant,
amnestic, anticonvulsant, sedative‐hypnotic
Indications:
- Alcohol withdrawal
- Acute anxiety
Contraindications:
- Hypersensitivity to any benzodiazepine
- Acute narrow angle glaucoma
Dose:
- Alcohol withdrawal – 1 mg SL, q 5 minutes to a total max of 4mg
- Acute anxiety – 1 mg SL, q 5 minutes to a total max of 2 mg
Propofol - Actions and uses / risks for abuse
Propofol
• Most widely used anesthetic
Actions and uses
• Unconsciousness develops within 60 seconds and lasts for 3 to 5minutes
• Sedative‐hypnotic for the induction and maintenance of
analgesia
• Mechanical ventilation and procedures
• Adverse effects
• Can cause profound respiratory depression
• Can cause hypotension
• Risk of bacterial infection
Risks for abuse
• Not a Controlled substance
• Often monitored at a Schedule One level.
• Widely available in operating rooms and other areas of hospitals and clinics
• No “high”
• Instantaneous but brief sleep period
• Patients awaken “refreshed” and talkative; many report feeling elated and even euphoric
Propofol promotes? and has what analgesic effects + extended sedation
Propofol promotes release of GABA (inhibitory
neurotransmitter). The result is generalized CNS
depression
Propofol has no analgesic actions
Extended sedation – infusions up to 4 mg/kg/min are
given
Propofol Flash Card
Generic name: Propofol
• Trade name: Diprivan
• Classification: Anesthetic
Indications: Conscious sedation
Contraindications: Hypotension DOUBLE CHECK (NEEDS TO BE ADDED)
Dose:
• Adult‐ 2‐2.5 mg/kg IV
• Usually administered in a 40 mg bolus q IO seconds until
desired effect is achieved
• Elderly/hypovolemia‐Administer half, the usual induction
dose
Ketamine
Anesthetic effects / Adverse psychologic reactions / Therapeutic Uses and Mechanisms of action
NMBAs
- Dissociative Anesthesia
- Sedation, immobility, analgesia, and amnesia
- May cause delirium, disturbing dreams
- ↓ with calm environment, benzos
- Schedule One Controlled Drug
Anesthetic effects
• Dissociative anesthesia
• Sedation, immobility, analgesia, and amnesia
Adverse psychologic reactions
• Hallucinations, disturbing dreams, and delirium
• Soothing environment
Therapeutic uses
• Anesthesia for young children with minor procedures
Mechanism of action
• Ketamine produces dissociative anesthesia by blocking
NMDA
receptors in the CNS
Ketamine Flash Card
Generic name: Ketamine • Trade name: Ketalar • Classification: Anesthetic • Indications: 1. Sedation prior to intubation 2. Pain management – refractory to analgesics ( OLMC required) Ketamine must be given slow IV push. If can cause apnea if given too fast.
Contraindications:
1. Hypersensitivity
2. Significant elevation of BP – relative consideration as this may
lead to angina/heart failure or aneurysms
Dose: Adult
- Sedation – 1.5 mg/kg SIVP/IO, do not repeat dose
- Sedation maintenance – 0.5 mg/kg SIVP/IO, q 10 minutes prn
- Pain management ‐ 0.2 mg/kg SIVP/IO
PEDIATRIC DOSAGE:
- Sedation – 1.5 mg/kg SIVP/IO, do not repeat dose
- Sedation maintenance – 0.5 mg/kg SIVP/IO, q 10 minutes prn
- Pain management ‐ 0.2 mg/kg SIVP/IO
