Clinical Pharmacology

Question 1

Discuss the taper of corticosteroids

Answer 1

Day 1: 30mg total divided QID
Day 2: 25mg total divided QID
Day 3: 20mg total divided QID
Day 4: 15mg total divided TID
Day 5: 10mg total divided BID
Day 6: 5 mg before breakfast

Question 2

Discuss the side effects of steroids

Answer 2

General
- weight gain
- central obesity
Skin
- skin thinning and purpura
- Cushing appearence 
Eye
- cataract
- glaucoma
Cardiac
- hypertension
GI
- peptic ulcer disease
Renal
- hypokalemia
OB
- amenorrhea
MSK
- osteoporosis
- avascular necrosis
Psychiatric
- psychosis
- depression
Endocrine
- diabetes
Infection
- increased risk of typical and opportunitistic infection

Question 3

Discuss the goals, indication, contraindications and procedure for desensitization

Answer 3

Goal
- alteration of immune response to drug resulting in temporary tolerance
Indication
- patient with immediate drug allergic reaction (IgE or non-IgE)
- no acceptable alternate drug or medication
- medication with desensitization protocol (Penicillin, Cephalosporin, Vancomycin, Septra, Platinum, Taxane, rituximab)
Contraindication
- significant desquamation reaction: Steven-Johnson
- non-IgE mediated reaction: serum sickness, nephritis, hepatitis
Procedure
- start by diluting drug which is slowly increased in concentration

Question 4

Discuss the pre-operative optimization with glucocorticoid

Answer 4

Non-Suppressed Hypothalamic-Pituitary Axis
- continue with same regimen if
- taking <3 weeks
- morning prednisone <5mg OD
- <10mg daily
Suppressed HPA Axis
- moderate surgical stress take usual dose plus 50mg IV before procedure and 25mg hydrocortisone Q8H for 24hrs after
- for severe surgical stress double the above
- used for patients taking >20mg/d for >=3 weeks
Intermediate Suppressed HPA Axis
- do not satisfy either of above
- 8am serum cortisol >275 then treat as non-suppressed
- 8am serum cortisol <275 then treat as suppressed
Adrenal Insufficiency
- hydrocortisone 150-300 IV daily divided into 3 doses for major surgery

Question 5

Discuss the pre-operative optimization for those with diabetes

Answer 5

Oral Diabetic Agent
- discontinue on day of surgery
Insulin
- monitor BG Q1-2H before, during and after surgery
- Night before
- if taking NPH/Levemir/Mixed then regular dose
- If taking Lantus then 80% of usual dose
- Morning of procedure for patients NPO
- hold short acting insulin
- NPH/Levemir: 1/2 usual dose
- Mixed: 1/3 morning dose
- Lantus: 80% morning dose
- Post-op
- short acting insulin on sliding scale

Question 6

Discuss the pre-operative optimization for antiplatelets

Answer 6

Aspirin
- continue or discontinue depending on indication
Antiplatelet
- should be discontinue 5-7d before surgery

Question 7

Discuss pre-operative optimization for anti-coagulation

Answer 7

Warfarin
- discontinue and bridge with LMWH
- start 5 days before surgery and normalize <=1.4 on day of surgery
- start LMWH 3 days before surgery and stopped morning before surgery
- post-surgery LMWH 1 day after low bleeding risk surgery or 2-3 days after high bleeding risk while resuming warfarin
- stop LMWH once warfarin reach therapeutic INR
LMWH
- discontinue 24hr before surgery
- post-surgery LMWH 1 day after low bleeding risk surgery or 2-3 days after high bleeding risk
Unfractionated Heparin
- discontinue 4-5hr before surgery
- post-surgery start 1 day after for low risk bleeding and 2-3d for high risk bleeding
NOAC
- discontinue 2-3d before surgery
- restart once hemastasis achieved for low bleeding risk or 2-3d for high risk

Question 8

Discuss antibiotic prophylaxis for surgery

Answer 8

Cefazolin 2-3g 60 min before and Q4H
- add Flagyl if GI surgery
Ciprofloxacin 500mg PO or 400mg IV
- cystoscopy
Doxycycline 100mg PO 1hr before and 200mg after
- for surgical abortion