Module 21 Geriatrics Flashcards
How much does organ function decline as you age
1% for every year after 30yo
Unchanged hemodynamics in elderly
Diastolic BP Resting systolic function Excitation-contraction coupling Contractile proteins ical levels
Respiratory changes that increase in elderly
Deadspace
Inspiratory capacity
Vital capacity
Aspiration risk
Potential for hypoxia 2/2 decreased elasticity
Respiratory changes that increase in elderly
FRC Closing volume Closing capacity Chest wall compliance Protective reflexes
Post op delerium more common in
Old
Male
Longer anesthetic
Parkinson’s
More common in ortho procedure
Subtle delayed onset of cognitive symptoms that may not present for weeks to months after surgery
Postoperative Cognitive Dysfunction
What is the most sensitive indication of renal function in elderly. Acceptable level
Creatinine clearance
Goal >30
MAC decreases in what fashion as you age
Decreases 4-6% for each decade over 40yo
What pharmacological principles do not change in elderly
EC fluid volume
Plasma volume
Red cell mass
Response to muscle relaxants
Propofol dose in elderly
1-1.5mg/kg
Etomidate dose in elderly
0.2mg/kg
What drugs do elderly require increase dosing
Atropine
Isoproterenol
What percent of CO goes to liver? Through what vessels
25% of CO
75% portal vein
25% hepatic artery
What two vessels form portal vein
Splenic and superior mesenteric veins
Most common hematologic disorder in alcoholic
Megaloblastic anemia 2/2 folate and thiamine deficiency
Best inhalation agent for liver failure patient
Isoflurane
What agents should you avoid in patient with porphyria
Barbiturates benzodiazepines ketamine Etomidate Lidocaine Ketorolac Dilantin Hydralazine Sulfonamides
What is the basic defect of porphyria
Metabolic disorder affecting biosynthesis of heme
Drugs that increase LES tone
Reglan Edrophonium Neostigmine Succinylcholine Metoprolol Alpha adrenergic agonists Antacids
What stimulates gallbladder contraction and release of pancreatic enzymes while inhibiting gastric motility
Cholecystokinin (CCK)
What causes acid secretion in stomach and histamine release in stomach
Gastrin
What causes serum alkaline phosphatase to increase
Biliary tract obstruction
Biochemical hallmark of carcinoid syndrome
Overproduction of serotonin
Electrolyte disturbance seen with anorexia
Hypokalemia
Hyponatremia
Hypochloremia
Metabolic alkalosis
What hormonal mediators are involved in carcinoid syndrome
Serotonin Bradykinin Histamine Prostaglandins Kallikrein
What are the stimuli for release of mediators from carcinoid tumor
Catecholamines
Histamine
Hypotension
Tumor manipulation
What drugs increase gastric pH and decrease gastric volume
H2 antagonists
Cimetidine
Famotidine
Ranitidine
H2 antagonists have what effect on liver enzymes
Bind cytochrome P450 systems
Cimetidine most inhibits them
How do antacids work
Raise gastric pH by neutralizing HCl
However they increase gastric volume
Best way of increasing gastric pH quickly
Non-particulate antacids (sodium citrate)
Non-particulate antacids lose effectiveness in how long
30-60 minutes
Only drug approved for diabetic gastroparesis
Receptor
Metoclopramide
Dopamine antagonist
Plasma protein changes in elderly
Most unchanged or slightly decreased (albumin)
Alpha 1 glycoprotein is increased
How does ANS change with aging
Decrease in response to beta receptor stimulation
Increase in SNS activity
Why is elimination of IV anesthetics half life increased in elderly
Decreased hepatic metabolism
Decreased plasma protein binding
Increase in fat increase Vd and prolongs lipid soluble drug half life
