Special Populations

Question 1

Geriatric PK

Answer 1

>65yo
↓total body water 53%
↓lean body mass 12% (lose muscle)
↑body fat
M 38-45%
F 36-38%
↓serum albumin 3.8g/dL
↓plasma protein = impaired protein binding
↓kidney weight 80%
↓GFR
↓hepatic blood flow 55-60% 
↓circulation time = longer onset
↑duration extended d/t metabolism/elimination changes
↓MAC 6% each decade after 40yo

Question 2

Postop Delirium

Answer 2

Most common postop complication
Assess preop cognitive function
Prevention = key
Avoid benzodiazepines

Question 3

Geriatric Considerations

Answer 3

Polypharmacy
Potential drug interactions w/ anesthesia
Renal impairment
↓plasma protein 
↓gastric motility
Avoid drugs w/ anticholinergic effects

Question 4

Muscle Relaxants

ELDERLY

Answer 4

↓skeletal muscle mass
Delayed onset
Extended DOA

Question 5

Anticholinergics

Answer 5

Tricyclic antidepressants
Antihistamines
Antimuscarinics
Antispasmodics
1st generation antipsychotics
H2-receptor antagonists
Skeletal muscle relaxants
Antiemetics

Question 6

Regional Anesthesia

ELDERLY

Answer 6

Anatomic changes in epidural & subarachnoid space
↓diameter & number myelinated fibers
↑dura permeability
↓CSF volume
Fixed dose & volume LA block spreads higher

Question 7

Obesity

Answer 7

Differences in tissue distribution
Hemodynamics
Blood flow to tissues
Plasma composition
Liver & kidney function

Question 8

IBW

Answer 8

Height (cm) - 100 M

Height (cm) - 105 F

Question 9

Lean Body Weight

Answer 9

LBW

= IBW + 30%

Question 10

Adjusted Body Weight

Answer 10

ABW

= IBW + 40%

Question 11

IV Anesthetics

OBESITY

Answer 11

Thiopental TBW prolonged DOA & 1/2 life

Propofol LBW induction
Maintenance TBW

Midazolam TBW loading dose (higher to achieve initial therapeutic effects)
Maintenance IBW

Dexmedetomidine 0.2mcg/kg/min ↓infusion dose to prevent cardiac SE

Question 12

Muscle Relaxants

OBESITY

Answer 12

Succinylcholine TBW
↑pseudocholinesterase activity

Non-depolarizing IBW
Hydrophilic

Question 13

Narcotics

OBESITY

Answer 13

Fentanyl ?
TBW dosing overestimates

Sufentanil TBW loading dose
Maintenance LBW
↑Vd & prolonged elimination 1/2 life

Remifentanil IBW
Not effected by weight

Question 14

Pediatric Drug Distribution

Answer 14

↓protein concentration
Blood-brain barrier
↑CBF
GFR 40mL/min at birth
↑100mL/min at 1yo

Question 15

Neonates/Infants

Answer 15

↓muscle mass ↑fat stores

↑blood flow to central organs (brain, heart, liver, kidneys)

Question 16

Water-Soluble Drugs

PEDIATRICS

Answer 16

↑dose required

Succinylcholine

Question 17

Cell Cycle

Answer 17

1. Cell growth
2. DNA synthesis
3. Mitosis

Question 18

Chemotherapy Patients ALL Experience

Answer 18

Nausea & vomiting

Question 19

Cisplatin

Answer 19

Lung, breast, ovarian, & bile duct cancers

Nephrotoxicity, peripheral neuropathy, nerve dysfunction

Question 20

Methotrexate

Answer 20

Lymphomas, breast, & bladder cancers

Myelosuppression w/ neutropenia & thrombocytopenia

Question 21

Bleomycin

Answer 21

Hodgkin’s & non-Hodgkin’s lymphoma

PULMONARY FIBROSIS

Question 22

Doxorubicin

Answer 22

Lymphomas, lung, ovarian, & thyroid cancers

Cardiotoxicity & myelosuppression

Question 23

Cetuximab

Answer 23

Colon & GI cancers

Interstitial lung disease

Question 24

Suppress NK Cell Activity

Answer 24

Volatiles
Barbiturates
Ketamine

Promote cancer cell mets

Question 25

Nitrous Oxide

Answer 25

Reduces purine & therefore DNA synthesis

Suppresses neutrophil chemotaxis, potentially facilitating cancer spread

Question 26

Opioids

Answer 26

Cellular & humoral immunosuppression

1° MORPHINE

Question 27

Propofol

Answer 27

PROTECTIVE EFFECTS
Anti-inflammatory effect
Inhibit COX-2
PGE-2 reduction
Weak β adrenoreceptor binding
Enhance antitumor immunity
NK function preservation

Question 28

Local Anesthetics

Answer 28

Reduce metastatic burden

Question 29

Cancer Surgery

IMMUNOSUPPRESSION

Answer 29

Stress
HPA stimulation
Inhaled anesthetics
Thiopental/Ketamine
Opioids & pain
Hypothermia
Blood transfusion
Inflammation
Catecholamine

PROLIFERATION
RECURRENCE
METASTASIS

Question 30

Cancer Surgery

INHIBITION

Answer 30

Regional anesthesia
Local anesthetics
Naltrexone
COX-inhibitors
β blockers