Geriatric

Question 1

Elderly CV changes

Answer 1

Loss of SA node cells = lower basal paraSNS tone, less response to atropine
Decreased response to beta-receptor (mostly agonist) & possibly alpha stimulation
Increased PVR - increased SNS at rest = hypotension with loss of SNS
Stiff arteries -> increased velocity of flow -> increased pressure in late systole -> ventricular hypertrophy -> slower contraction/relaxation -> atrial kick required**
Pressors>fluids (though more sensitive to hypovolemia)

Question 2

Elderly & IV agents

Answer 2

Less protein binding = increased free fraction = more bang for your buck but with slower redistribution. Waking up also takes longer - clearance decreases

Question 3

Elderly & inhalation agents

Answer 3

Decrease MAC by 6% per decade over 40 yoa, greater hypotension from decreased baroreceptor reflex

Question 4

Elderly & pulmonary changes

Answer 4

Loss of elastin from free radicals, increased closing capacity (may be more than FRC), increased V/Q mismatch, loss of muscle mass - fatigue easily, less CNS response to pulmonary changes, increased risk of aspiration

Question 5

Elderly & renal changes

Answer 5

Loss of glomeruli - decreased clearance, urine concentration & sodium retention, decreased thirst, decreased GFR by 20 mL/min every 20 years after 20

Question 6

Elderly & thermoregulation

Answer 6

Shivering occurs 1 degree below that required for vasoconstriction - more prone to hypothermia

Question 7

Postoperative Cognitive Dysfunction in elderly

Answer 7

Those with delirium don’t necessarily have POCD, those without don’t necessarily not have POCD. POCD increases mortality