213 Critical Care Anesthesia Flashcards
Types of anesthesia
Local, regional, general
Ideal anesthetic characteristics
Easy, controllable, and versatile
- nonflammable/non explosive
- cheap, stable, easily stored
- wide margin of safety
- does not effect organs
- AAAA
- rapid adjustment in depths of anesthesia
- pt experience (pleasant, non-irritating, no n/v, induction and recovery short with no after effects)
Phases of anesthesia
Induction, maintenance, emergence
Stages of anesthesia
Stage I/analgesia: conscious and rational
Stage II/ delirium/excitement: unconscious, body still responds reflexively, irregular breathing pattern with breath holding
Stage III/ surgical anesthesia: increasing degrees of muscle relaxation, unable to protect airway
Stage IV/imminent death: medullary depression— CVS & resp depression
Describe the ASA Physical Status Classification System
Risk assessment:
ASA I- healthy, no issues
ASA II- mild disease (ie smoker), no functional limit
ASA III- severe systemic disease with functional limit
ASA IV- severe systemic disease with constant threat to life (ie copd on home o2, dialysis)
ASA V- will did if they don’t have sx/intervention (ie ruptured AAA)
ASA VI- brain dead
Describe the revised cardiac risk index as it pertains to non cardiac sx
1 point each
High risk sx
Prior TIA or CVA
Hx of CAD
HX of CHF
IDDM
Serum creatinine >2
Describe evaluation of preoperative pulmonary risk assessment
Gupta post-op respiratory failure risk. Predicts risk of mech vent for longer than 48hrs postop or reintubation within 30 days
Functional status
ASA class
Sepsis
Emergency case
Type of procedure
Describe and relate the affects of anesthesia on the CVS, Resp, and neuro systems
CVS— hypotension via vasodilation or blunted sympathetic drive
RR- hypoventilation/apnea
CNS- sedative/hypnotic, amnesia
Big 3 allergic reactions in anesthesia
Rocuronium, chlorhexidine, Ancef
Principles of anesthesia to remember in obese pt
Increased volume of distribution (prolonged effect if Rx is liphophyllic)
Increased CO
Increased renal clearance rate
General rules of thumb to follow when dosing obese pts
Almost always IBW dosing— can always give more, cannot take away
**TBW dosing for depolarizing NMBA (succinylcholine), induction (propofol, midazolam), fentanyl
loading dose “fills the bucket” (TBW), maintenance “slowly drains” (IBW)
Why are opioids dodgy in obese pts?
Narrow therapeutic window
- decreased safe apnea time
- greater clearance
- fentanyl is highly lipophilic= use TBW
Drugs and their doses for RSInduction
Sedative:
Propofol 1-2.5mg/kg or 0.5-1.0mg/kg
Ketamine 1-2mg/kg
Midazolam 0.3-0.35mg/kg or 0.2mg/kg
Opioid:
Fentanyl 0.5-1.0mcg/kg or 25-100mcg
NMBA:
Rocuronium 0.6-1.2mg/kg
Succinylcholine 1.0-1.5mg/kg
Vasopressors:
Phenylephrine 50-100mcg q 2-5min
Norepinephrine 2-20mcg/min
Epinephrine 2-20mcg/min
Drugs and doses for maintenance of GA
per Rico
Sedative:
Propofol 25-100mcg/kg/min
- standard starting point is 50-60mcg/kg/min or 30-35mcg/kg/min for gertiatrics
(2%= 2000mg/100mL= 20mg/mL or
1%= 1000mg/100mL= 10mg/mL)
Ketamine: half induction dose/hr
Midazolam&Morphine: 2.5-5mg/hr, if you get up to 20&20mg/hr consider switching strategy
Opioid:
Fentanyl 25-50mcg/hr or 50-100mcg/hr for higher tolerance or painful state
NMBA:
Rocuronium 1mg/kg/hr (depends)
or 50mg q 30-45min
Vasopressors:
Phenylephrine 50-100mcg q 2-5min
Norepinephrine 2-20mcg/min
Epinephrine 2-20mcg/min
What are the 5 anesthesia procedures?
- PSA: procedural sedation analgesia
- SFI: sedation facilitated induction
- Awake approach
- PAI: Paralytic assisted induction
- RSI: rapid sequence induction
