42. Properties of Intravenous Anesthetic Agents Drug Induction and Recovery Main Unwanted Effects Notes thiopental Fast onset (accumulation occurs, giving slow recovery) Hangover Cardiovascular and respiratory depression Used as induction agent declining. ↓ CBF and O2 consumption Injection pain etomidate Fast onset, fairly fast recovery Excitatory effects during induction Adrenocortical suppression Less cvs and resp depression than with thiopental, Injection site pain propofol Fast onset, very fast recovery cvs and resp depression Pain at injection site. Most common induction agent. Rapidly metabolized; possible to use as continuous infusion. Injection pain. Antiemetic ketamine Slow onset, after-effects common during recovery Psychotomimetic effects following recovery, Postop nausea, vomiting , salivation Produces good analgesia and amnesia. No injection site pain midazolam Slower onset than other agents Minimal CV and resp effects. Little resp or cvs depression. No pain. Good amnesia.
43. Non-barbiturate induction drugs effects on BP and HR Drug Systemic BP Heart Rate propofol ↓ ↓ etomidate No change or slight ↓ No change ketamine ↑ ↑
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57. MAC and Lipid Solubility 1.85 53 sevoflurane 105 1.4 nitrous oxide 1.90 65 ether 1.68 98 enflurane 0.76 224 halothane MAC Lipid/Gas Coefficient Agent
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60. Uptake, Distribution and Elimination of Anesthetic Gases, p29 0.74 1.68 1.15 2.05 104 MAC 3 1.4 Isoflurane 4 1.9 enflurane 6 12.1 ethyl ether 5 2.3 halothane 2 0.69 sevoflurane 1 0.47 N 2 O Rapidity of Onset Blood/Gas ( λ ) Agent
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78. yes Marked Yes Yes Respir depression No Significant Significant No Respir irritation Slightly reduced Stable Slightly reduced Reduced Cardiac output Stable Increased Increased Reduced Heart rate Significant Significant Significant Moderate Muscle relax 3 – 6% 0.02% 0.2% 12 – 25% Metabolism No No No Yes Hepatotoxic Fast Very fast Moderate Slow Recovery Fast Fast Moderate Slow Alveolar equilibration sevoflurane Desflurane Isoflurane Halothane