Special Populations Flashcards
Summary of Pharmacokinetic changes in the eldery
decrease in TBW, Lean body mass, serum albumin, kidney weight and hepatic blood flow
Increase: body fat
increase in alpha 1 glycoprotein
Anesthesia in the Elderly require
meticulous preoperative assessment
detailed management of intraoperative variables and disease states
cautious titration of drug administration and dosages
What complicates pain control in the elderly?
pre-existing cognitive impairment
fear of opioid related side effects (opioid requirements are inversely related to patients age and essentially independent of body size)
Regional Anesthesia and the Elderly
anatomic changes in epidural and subarachnoid space
diameter and number of myelinated fibers is decreased
increased permeability of dura and decreased volume of CSF
occlusion of intervertebral formania with fibrous connective tissue
with fixed dose of volume of local anesthetic, spread of block is higher in elderly
Muscle Relaxants and the Elderly
elderly have reduced muscle mass onset of action is delayed duration of action is extended antagonism remains unchanged reduced plasmacholinesterase
General Geriatric Population Considerations
renal impairement decreased plasma protein reduced gastric motility and acidity altered distribution increased total body fat decreased plasma albumin concentration decreased hepatic flow decreased GFR
Drug Classes that may induce POD
tricyclic antidepressants, antihistamines, antispasmodics, first generation anyti-psychotics, H2 receptor antagonist, skeletal muscle relaxants, anti-emetics corticosteroids meperidine sedative hypnotics polypharmacy
Pharmacology and Obese Patients is significantly influenced by
difference in tissue distribution hemodynamics blood flow to tissue types (organs, adipose, splanchnic) plasma composition liver and kidney function
Pharmacokinetic factors in Obese patients are influenced by
lipid solubility of drug
diffusion through body compartments
Overall, dosing with obese patients should consider
volume of distribution for loading dose IBW for drugs that prefer lean tissue TBW for drugs with equal distribution to lean and adipose tissue Clearance for. maintenance dose lean body weight
Thiopental Dosing
TBW
Propofol Dosing
LBW for induction
TBW for maintenance
Midazolam Dosing
TBW loading dose
IBW mantainence
Dex Dosing
0.2mcg/kg/min
Succ Dosing
TBW
Roc/ Vec/ CIs/Pan Dosing
IBW
Fentanyl dosing
inconclusive
Sufentanil Dosing
Loading Dose TBW
Mantainence LBW and response
Remifentanil Dosing
IBW
What PK properties changes from fetus to baby to adult
VD, elimination, receptor sensitivity, side effects, organ function
IV drug distribution in children depends on
circulating blood elements
blood tissue partition coefficients
distribution of blood flow
Alpha 1 acid glycoprotein and albumin levels in infants is
lower
Blood flow and pediatric pharmacology
relatively smaller muscle mass and greater fat stores in neonates and infants
greater blood flow to central organs (brain liver heart kidneys
water soluble drugs may require higher doses
mismatch in tissue types effects durations of actions
Other factors that affect pediatric drug distribution
integrity of BBB -rapid uptake of anesthetics into CNS -higher brain blood flow receptor affinity nad sensitivity developmental changes in hepatic metabolism changes in renal function
What are the two questions as a CRNA for the pharmacology of cancer patients?
how will the chemotherapy drugs affect your patients?
how will your anesthetic affect the patient’s prognosis
Cell cycle and checkpoints
cell growth checkpoints
DNA synthesis checkpoint
mitosis checkpoint
cell growth checkpoint
occurs toward the end of growth phase 1
checks whether the cell is big enough and has made proper proteins for the synthesis phase
if not, cell goes through resting period until it is ready to divide
DNA synthesis checkpoint
occurs during synthesis (S)
checks whether DNA has been replicated correctly
if so, cell continues to mitosis
Mitosis Checkpoint
occurs during mitosis phase
checks whether mitosis is complete
if so cell divides and cycle completes
Clinical and Toxicity of Cisplatin
lung cancer, breast cancer, bile duct cancer, ovarian cancer
nephrotoxicity, peripheral neuropathy, nerve dysfunction
Clinical and Toxicity of Methotrexate
breast cancer, lymphomas, bladder cancer
myelosuppression with neutropenia and thrombocytopenia
Clinical and Toxicity of Bleomycin
hodgkin’s and non-hodgkin’s lymphoma
pulmonary fibrosis
Clinical and Toxicity of Doxorubicin
Lung cancer, lymphomas, ovarian CA and thyroid cancer
cardiotoxicity, myelosuppression
Clinical and Toxicity of Cetuximab
Colon CA
GI cancer
interstitial lung disease
Volatiles, barbs and ketamine
suppress NK cell activity and can promote cancer cell mets
Nitrous Oxide
reduces purine and thus DNA synthesis and also suppresses neutrophil chemotaxis, potentially facilitating the spread of cancer
Propofol
seems to exhibit protective effects through various mechanisms, including anti-inflammatory effect inhibitiong of COX2 and reduction of PGE2, weak bet adrenereceptor binding, enhancement fo antitumor immunity and NK funciton preservation
Perioperative opioids
may produce cellular and humoral immunosuppression
morphine example
Local anesthetics have been shown to
reduce metastatic burden
