Characteristics of Common Induction Drugs (Exam 2)

Question 1

Propofol: E 1/2 Time (Hours)

Answer 1

0.5-1.5 Hours

Question 2

Propofol: Vd (L/kg)

Answer 2

3.5 - 4.5

Question 3

Propofol: Clearance (mL/kg/min)

Answer 3

30 - 60

Question 4

Propofol: Effects on BP & HR (increase/Decrease)

Answer 4

BP: Decreased
HR: Decreased

Question 5

Etomidate: E 1/2 Time

Answer 5

2 - 5 Hours

Question 6

Etomidate: Vd (L/kg)

Answer 6

2.2 - 4.5

Question 7

Etomidate: Clearance (mL/kg/min)

Answer 7

10 - 20

Question 8

Etomidate: Effects on BP & HR (increase/Decrease)

Answer 8

BP: No change - Decreased
HR: No Change

Question 9

Ketamine: E 1/2 Time

Answer 9

2 - 3 Hours

Question 10

Ketamine: Vd (L/kg)

Answer 10

2.5 - 3.5

Question 11

Ketamine: Clearance (mL/kg/min)

Answer 11

16 - 18

Question 12

Ketamine: Effects on BP & HR (increase/Decrease)

Answer 12

BP: Increased
HR: Increased

Question 13

Where do all these drugs work?

Answer 13

They all work on GABA!!
Ketamine works at a lot of places
-NMDA as Non-comp. antagonist

-Opioid receptors (mu/kappa/delta)

-GABA A (weak)

Question 14

Ketamine side effects

Answer 14

-Drooling
-Delirium
-Dissociation

Question 15

Ketamine: How to treat Drooling and Delirium?

Answer 15

-Glycopyrorolate (0.2mg)
-Versed (admin 5 min. prior to ketamine dose)

Question 16

Ketamine: Induction Dose

Answer 16

INDUCTION:
-0.5 -1.5 mg/ kg IV
-4-8 mg/kg IM

Question 17

Ketamine: Maintenance & Sub anesthetic dose

Answer 17

0.2-0.5 mg/kg IV

Question 18

Ketamine: Post-Op Sedation & Analgesic Dose

Answer 18

1-2 mg/kg/hr

Question 19

Ketamine: Neuroaxial Analgesia

Answer 19

-Epidural: 30 mg
-Intrathecal/spinal/ subarachnoid: 5-50 mg

Question 20

Ketamine: Onset & Duration

Answer 20

Onset:
-IV: 1 min
-IM: 5 min
Duration : 10-20 min

Question 21

Ketamine: Metabolism

Answer 21

-Hepatic, CYP 450
-ACTIVE METABOLITE: Norketamine (1/3 potency of parent, causes prolonged analgesia)

Question 22

Ketamine: Drug interactions and Effects

Answer 22

-Volatile anesthetic: Hypotension

-NDNMB drugs: Enhanced

-Succinylcholine: Prolonged

Question 23

Ketamine: CV Effects

Answer 23

-THINK SNS EFFECTS!

• Can cause sudden ↓BP d/t depletion of catecholamine stores.
  -Direct myocardial suppressant
• Ephedrine won’t work bcuz indirect action
• so give a direct acting vasopressure like phenelyphrine

Question 24

Ketamine: Pulmonary Effects (There’s a bit here)

Answer 24

-↑ Pulm artery pressure up to 44 mmHG
- No depression of ventilation

• PaCO2 ventilation response maintained

‣ Upper airway relflexes and tone maitained = ↑ of laryngospasms

‣ ↑ Salivation and tracheobrochial mucous secretions

‣ ↑ Bronchodilation (no histamine release)

Question 25

Ketamine: Other Side Effects

Answer 25

-Benefits: AMNESTIC and ANALGESIC

-BUUUUT…

 -Dissociative anesthesia

 ‣** Nystagmus**

 ‣ Non- communitave   wakefullness

 ‣ Hypertonic skeletal movements

Question 26

Ketamine: Contraindication

Answer 26

• Systemic /pulm HTN
• Increased ICP

Question 27

Etomidate: Metabolism

Answer 27

• Hydrolysis hepatic microsomal enzymes
• Plamsa esterases

Question 28

Etomidate: Excretion / Clearance

Answer 28

• 85% in urine
  ‣ 10-13% in bile

-Clearance 5x faster than thiopenthal
***wake up fast

Question 29

Etomidate: CNS Effects

Answer 29

- ↑ incidence of myoclonus (50-80%) Greater than all others

• Give Benzo or Opiod to inhibit
  myclonus (FENT 1-2 mcg/kg
  IV)
  ‣ USE CAUTION WITH SEIZURE
  PT!!!

Question 30

Etomidate: CV Effects

Answer 30

CARDIOPROTECTIVE AGENT

‣ Good for patients with low EF

‣Minimal changes in HR, SV, CO, Contractility

‣ SUDDEN HYPOTENSION w/ HYPOVOLEMIA w/ high 0.45 mg/kg IV induction dose

Question 31

Etomidate: Resp.

Answer 31

-Ventilation depression < barbs

-Stimulates CO2 medullary centers

Question 32

Etomidate: Special Considerations

Answer 32

-No analgesia, so you will need multimodal anesthesia

-Adrenocorotical Suppression: Dose depenedent, inhibits the conversion of cholesterol to cortisol

 ‣↓ STRESS RESPONSE 
      ‣↓ BP 
      ‣↑Mechanical ventilation
           time
      ‣ USE CAUTION w/ Sepsis     
          and hemorrhage

Question 33

Etomidate: Adverse Effects

Answer 33

-Adrenocorotical Suppression: -Dose depenedent,
-Inhibits the conversion of cholesterol to cortisol,
‣↓ STRESS RESPONSE
‣↓ BP
‣↑Mechanical ventilation
time
‣ USE CAUTION w/ Sepsis
and hemorrhage

Question 34

Propofol: Metabolism

Answer 34

-Hepatic: CYP 450

-Metabolites: Water soluble sulfate and glucoronic acid excreted by kidney

Question 35

Propofol: Context Sensitive Half Time

Answer 35

40 minutes (on 8hr infusions)
Shorter than all barbs, not as lipid soluble

Question 36

Propofol: Clearance (not just a number!!)

Answer 36

30-60 mL/kg/min
-Plasma (lungs) > Hepatic flow
-Tissue uptake > CYP 450

Question 37

Propofol: CV

Answer 37

-↓ BP (more than thiopental)

• ↓BP exaggerated in hypovolemia, elderly, LV compromise

Question 38

Propofol: Resp.

Answer 38

**-Dose Dependent apnea

-Synergistic with opioids!! = ↑ resp. depression

-Bronchodilator effects = GOOD

Question 39

Propofol: Adverse Effects

Answer 39

Prolonged Gtt’s can cause:
‣Hepatocellular injury
‣ PROPOFOL INFUSION SYNDROME

Question 40

PRIS: What is it

Answer 40

PROPOFOL SYNDROME:
‣ Gtt’s > 75 mcg/mg/min for > 24 hrs

‣ S/sx: Lactic acidoses, Brady-dysrhthmias, Rhabdo.
‣ SEVERE refractory brady in PEDS

‣ DX: ABG and serum lactate

‣ Reversible in early stages

‣ Cardiogenic shock → ECMO