IV Anesthetics Flashcards
Redistribution
Onset and offset have to do with redistribution, not metabolism
First redistributes to vital organs, then muscle, then fat
Alpha half life
Initial rapid drop in drug concentration because it is leaving blood and going into tissues
Beta Half Life
Once evenly distributed, blood level doesn’t drop as fast, now being metabolized and eliminated
GABA-mimetic
Inhibitory transmitter.
Controls the amount of chloride that goes into a cell. When activated, causes channel to open, Cl flows in and makes cell more negative (hyperpolarizes it) and makes it more difficult to reach AP
Drug: benzos, barbs, etomidate, propofol
Glutamate and NMDA receptor antagonist
Cause inhibition of excitatory receptor
Drugs: ketamine
Presynaptic A2 receptor agonist
Causes nerves to release less NE from negative feedback (sympatholytic)
Dexmedetomodine
Don’t give to asthmatics or children with egg allergy (proven wrong)
Propofol: d/t sulfates in formula
Effect on CMRO2 and CBF
Dose dependent decrease
EXCEPT KETAMINE! (Increase CMR)
Ketamine Effect on BP, HR, and lungs
Increases BP/HR
Bronchodilates
Agent of choice in wheezing pt
Ketamine—> bronchodilates d/t NE release
Propofol Infusion Syndrome
Presence of impaired systemic micro circulation with issue hypoperfusion and hypoxia
Fatty acid metabolism and mitochondrial activity are impaired creating an oxygen supply and demand mismatch that results in cardiac and peripheral muscle necrosis
Rhabdomyolysis: gets bad then clogs kidneys
Metabolic acidosis
Causes Dissociative Amnesia
Ketamine
Pt is in catatonic state and appears separated from the environment and has analgesic and amnesic effect but retains most protective reflexes
Ketamine Effects
Increased CMR, CBF, ICP Nystagmus Increased ICP Increased BP/HR Bronchodilator Maintain respirations and airway reflexes Increased salivation and secretions Increased muscle tone Emergence delirium (give benzos) *analgesia
Causes Acute Adrenal Suppression
Etomidate: inhibits 11 B h. Preventing synthesis of steroids and aldosterone in the body. Pt can’t tolerate stress
Benzo SE
Anticonvulsant Anxiolytics, sedation, anterograde amnesia Minimal CV effects Depression of airway/muscle reflexes Respiratory depression at high doses Centrally mediated muscle relaxation Depressed cellular immunity
Propofol SE
Anticonvulsant Antiemesis Sedation Decreased CMRO2 EEG burst suppression Decreased SVR Pain on injection Hyper triglyceridemia Depression of airway Myocardial depression Rhabdymolysis with infusion syndrome
Etomidate SE
EEG burst suppression Sedation Decreased CMRO2 Respiratory depression Myoclonus Adrenal suppression Pain on injection Minimal vasodilation Minimal cardiac depression N/V Anticonvulsant
Ketamine SE
Dissociative sedation Emergence delirium Analgesia Nystagmus Increased salivation Bronchodilation Indirect myocardial stimulation Increased SVR from sympathetic outflow
Precedex SE
Analgesia Sedation Decreased salivation Preserved respiratory drive Decreasing shivering Variable hyper/hypotension Bradycardia
