1. pharmcokinetics
Allie punke

2. Critical care
absorption

3. absorption
Passive diffusion OR Carrier-mediated absorption is affected in critically ill patients?
What is the reasoning for the correct answer to above question in critically ill patients?
In critically ill patients, shunting of blood occurs away from what organs?
How is absorption affected by the above question?
What class of drug often used in this patient population may increase/decrease perfusion (specifically gut)?

4. absorption
If critically ill patients are not fed orally or enterally, what may occur in ~ 3-5 days?
What is the implication of this for absorption of drugs?
If given medication for stress ulcer prophylaxis, how can this affect absorption?

5. absorption
____________ occurs frequency (~60% incidence) in critically ill patients and leads to altered absorption. The gastric residual volume can be used to determine if a patient has this.
What drug(s) could be used to improve this alteration?

6. absorption
AB was admitted to the ICU. She is being started on enteral nutrition. What (if any) modifications should be made avoid an interaction with phenytoin?
A. Nothing. It does not interact with phenytoin.
B. Stop the feedings for about 30 minutes when giving phenytoin to prevent a high concentration
C. Stop the feedings for about 2 hours when giving phenytoin
D. The phenytoin dose should be increased to counteract any absorption problems. C

7. absorption
When a patient is receiving enteral nutrition, there are a few medications that interact with the feedings.
Phenytoin
Effect: Dec. serum levels
What to do: Hold tube feedings ~2 hours around dose
Warfarin
Effect: Decreased INR
What to do: Hold tube feedings or increase dose
+/- Fluroquinolones
Effect: Maybe decreased levels…maybe not clinically significant.
Could consider the site of infection (UTI vs bacteremia) to determine if significant interaction or not

8. Volume of distribution
Critical care
Volume of distribution

9. Volume of distribution
What are some factors that can change Vd in ICU patients?
Fluid shifts: large volumes administered
Comorbidities
pH changes
Protein binding
Albumin is…. Increased Or decreased in patients?
AAG is….Increased Or decreased in patients?
For crystalloids…25% of it stays intravascularly, 75% interstital.

10. Ph changes

11. Protein binding

12. Volume of distribution
MB is admitted to the ICU. Her pH is Which of the following types of drugs would have an increased volume of distribution?
A. Acidic drugs
B. Basic drugs
C. Neither
D. Both A

13. Volume of distribution
AB is admitted to the ICU and needs to be started on an aminoglycoside. Based on other critically ill patients, AB will also likely require:
A. Higher loading dose
B. Lower loading dose
C. Loading dose will not change
A, B
Follow up: Why did we give AB a higher LD?
A. Increased excretion of the drug
B. Increased volume of distribution
C. Both
D. Neither

14. Volume of distribution
Remember…
Volume of distribution is used to calculate LD
Clearance is used to calculate MD
Be able to take these principles and apply to a patient’s dosing regimen

15. Antibiotic types
What type of antibiotics (hydrophilic vs lipophilic) will the Vd be affected in critically ill patients?
Name 3 hydrophilic antibiotics
Name 3 lipophilic antibiotics.

16. Critical care
metabolism

17. metabolism Know the equations for High E and Low E
CL:
Css:
Css,u:
Low:
The dose is changed when what parameter is altered?
Recognize which drugs are low E vs high E
Recognize which drugs are bound to albumin vs AAG

18. metabolism

19. High e

20. Low e

21. metabolism
AB is a patient in the ICU. Her albumin level recently fell to 1.9 from 4. Do any of her drugs need to be adjusted?
A. Phenytoin dose needs to be lowered.
B. Phenytoin and morphine doses need to be lowered.
C. Ceftriaxone dose needs to be lowered.
D. Morphine dose needs to be lowered.
D (high E drug) Css,u changes.

22. metabolism
AB is started on propofol for sedation. Her albumin level is 2.4. Should the propofol dose be adjusted?
A. Yes, the Css and Css,u are both affected.
B. No, neither the Css or Css,u are affected.
C. Yes, because only Css is affected.
D. Yes, because only Css,u is affected. D

23. Critical care
excretion

24. excretion Majority of drugs are excreted by:
A. Bile/feces
B. Lungs
C. Kidney
How is renal function affected for patients in the ICU?
For patients with AKI that are receiving CRRT, how is antibiotic dosing affected?
What type of patients may have ARC—augmented renal clearance?

25. Questions?