IV anesthetics Flashcards
Types of anesthesia
“Balanced Anesthesia” - uses mostly IV drugs to induce anesthesia + accelerate the excitation phase with inhaled anesthetics to maintain anesthesia
Total Inhalation Anesthesia - mostly used in children
Total IV Anesthesia (TIVA) - usually used in smaller interventions
List the IV anesthetics
Propofol and Fospropofol Etomidate Ketamine Thiopental Midazolam
Opioids:
Fetanyl, Sufetanyl, Remifetanyl
Antispychotics:
Haloperidol, Droperidol
What is neuroleptic analgesia
Combination of opioid analgesic (i.e. fentanyl) with “neuroleptic” / antipsychotic (i.e. droperidol)
Produce a “detached, pain-free” state.
Results in immobility, analgesia and a variable degree of amnesia. Rarely used today.
Original combo was haloperidol and phenoperidine.
Propofol uses and mechanism
Enhances GABAa
Used for induction AND maintenance.
Sedative, hypnotic, anterograde amnesia, and antiemetic effects
No analgesic effects.
Anti-emetic effect helps prevent aspiration pnemonia
Propofol SEs
Strong respiratory depression
Strong vasodilation of vein and arteries, large MAP drop.
Long propofol infusions cause acidosis for resp depression.
Rare long infusions: Propofol inf syn. Rhabdomylosis, acidosis, hepatomegaly, and kidney failure.
Ketamine uses and mechanism
Inhibits NMDA receptors
Used in induction
Causes dissociative anesthesia, Open eyes with a nystagmus.
Also analgesia and amnesia
Good for small operations, especially in children or disabled people who may have bad compliance - dissociative.
Ketamine SEs
Respiratory Stimulation and bronchodilation
Also Cardiac stimulation
Hallucinations and emergence reactions, vivid dreams.
Etomidate uses and mechanism
GABAa potentiation.
Rapid effect, 30-60s
Used only for induction
Has only minimal cardiac and respiratory effects.
‘Stabilizes’ the cardiovascular system and is a good induction anesthetic for patients with hypovolemia or heart problems.
Etomidate SEs
Potent, long lasting adrenocortical suppression for several hours after use.
Need to make sure cortisol doesn’t drop too low
Post-op nausea
Myoclonic twitches and jerks.
Thiopental mechanism and use
Potentiates GABAa, increasing the duration of channel opening.
Least often used.
Has profound cardiac and respiratory suppression, and decreases ICP due to constriction of cerebral vessels.
Can also cause laryngospasm.
THIS is its main use, and used in patients that have cranial masses or compressive lesions.
Thiopental kinetics
Ultra rapid, very lipophilic with
onset 30 seconds LOC 60s.
lasts 5-10 minutes
Redistribution to adipose and muscle.
Benzodiazepines for anesthesia
Midazolam - Also very short acting, and can be used for induction of more significant surgeries.
Diazepam, Lorazepam - longer acting
Benzos used as concious sedation for minor procedures, colonoscopy.
i.v.
The fuck are the ‘perioperative medications’
Benzodiazepines - for anxiolytic and amnesia-producing effects
Analgesics
Antiemetics - including anti-emetic effects of propofol; to ↓ anesthesia/analgesic-induced emesis
Antimuscarinics - to ↓ parasympathetic functions, intubation gag reflex, atropine is used
CV medications - β blockers etc. are used to modulate CV activity during surgery
Prokinetics post-operatively
