Geriatrics

Question 1

Primary mechanism of Aging

Answer 1

DNA

DNA damage, mitochondrial DNA mutations, epigenetic drift, and loss of telomeres

Question 2

Secondary mechanism of aging

Answer 2

Cellular

Damage to mechanisms that prevent younger cells from damage and/or nutrient shortages

Question 3

Tertiary mechanism of aging

Answer 3

Pathological

Failure of compensatory mechanisms, healthy cell function decreases for a variety of factors, neurohumoral
signaling processes can fail.
-HTN, Cx

Question 4

Functional reserve

Answer 4

The ability of organs to increase function above level necessary for normal baseline activity.

Peaks at 30…

Question 5

4 factors that determine outcome & risk

Answer 5

Age

Patient health and disease management

Urgent vs elective

Type of surgery

Question 6

Changes in body composition with aging

Answer 6

-less skeletal muscle
-more fat
-lower metabolism
-less total body water
-decreased albumin
-poor thermoregulation

Question 7

Pharmacology of aging

Answer 7

• reduced protein binding= increased drug crossing BBB

-bolus take longer to peak effect- circulation

-vessel rich acquires meds rapidly

Question 8

Water soluble meds Vd in aging

Answer 8

Smaller Vd

-less total body water

Question 9

Lipid soluble meds in aging and Vd

Answer 9

Larger Vd

-think increased fat

Question 10

Why are NMBD prolonged in elderly?

Answer 10

Motor neurons decrease with age

Question 11

Calculating MAC in the elderly

Answer 11

6% decrease in MAC per decade over 40*******

Question 12

CNS and aging

Answer 12

Brain mass decreases after 50

Neurotransmitters decline

Spinal sensory block prolonged

Post op delirium and cognitive dysfunction

Question 13

Liver changes in elderly

Answer 13

Mass decreases, coincides with 20-40% reduction in blood flow

Decreased plasma drug clearance and phase one drug metabolism

Question 14

Gastric changes with age

Answer 14

pH Rises

Emptying-prolonged

Question 15

Renal changes elderly

Answer 15

Cortical mass decreases by 20%

50% of glomeruli are lost by 80

Prone to electrolyte imbalances

Question 16

Rate of GFR decrease

Answer 16

1ml/min/yr after 40

Question 17

Most sensitive indicator of renal function

Answer 17

Creatinine clearance

For adult men, 0.74 to 1.35 mg/dL (65.4 to 119.3 mmol/L).
For adult women, 0.59 to 1.04 mg/dL (52.2 to 91.9 mmol/L).

Question 19

Explain vagal tone in elderly

Answer 19

It is increased

They rely on constant sympathetic outflow to maintain organ perfusion- makes them less sensitive to exogenous catecholamines

-adrenergic receptor decreases= decreased HR

Question 20

When SBP is >80mmhg than DBP

Answer 20

Increase in mortality
-Renal failure
-Stroke
-CAD

Question 21

Physiology of Systolic hypertension

Answer 21

General arterial stiffening = pressure wave transmits more rapidly. *
1. Seen in aortic root just after dicrotic notch on EKG

Half of stroke volume remains in aorta after ejection
-pressure must increase more to stretch aorta and accommodate volume

Question 22

Hypertrophy

Answer 22

INCREASED dependence on atrial kick***
-tachycardia can be life threatening

Stiff ventricle-impaired filling
Slows diastolic relaxation

Question 23

Veins in HTN

Answer 23

Stiffening, impaired ability of body to buffer changes in position during surgery-

Can cause more dramatic hemodynamic shifts

Question 24

Cardiovascular changes geriatric

Answer 24

Arterial tree is less compliant (fibrous tunica media)

HTN

Increased Circulation time

CAD

LVH- easy fluid overload

Decreased CO

Question 25

Big take away for medication admin in elderly

Answer 25

Give less Be aware of active metabolites reliant on renal excretion(morphine)

Question 26

Easy way to kill the elderly with spinals

Answer 26

Intrathecal opiates Elderly resp drive is already diminished

Question 27

Pulmonary changes in elderly

Answer 27

Increased chest wall stiffness Decreased stiffness of lung parenchyma-less elastin Small airways require more volume to open Diaphram flattening

Question 28

Closing capacity in the elderly

Answer 28

Increases *becomes harder to keep lungs open

Question 29

Respiratory Nervous system changes in elderly

Answer 29

50% reduction in hypercapnic response Decreased response to hypoxia 75% OSAish Cough/swallowing impaired

Question 30

Decrease in skin temp of 1 degree F changes core temp by:

Answer 30

0.2 degree F

Question 31

Thermoregulation in elderly

Answer 31

Aging makes thresholds MORE impaired by an additional 2 degrees F

Question 32

Impact of inhaled agents on thermoregulation

Answer 32

DECREASE physiologic response to both thresholds by up to 7 degrees Fahrenheit

Question 33

Risks of hypothermia

Answer 33

Myocardia ischemia ▪ Surgical wound infection ▪ Coagulopathy ▪ Increased blood loss ▪ Impaired drug metabolism ▪ Causes metabolic stress

Question 34

How do lab values change in the elderly?

Answer 34

They don’t! In absence of pathological condition

Question 35

Problem with smoking cessation

Answer 35

Return of ciliary function 2-6 weeks post cessation= very reactive airway/need for suctioning

Question 36

Intraop anesthetic management of elderly

Answer 36

Small doses of induction agent- give it time Phenylepherine infusion on standby Prone to venous pooling- decreased preload Careful with volume-consider albumin Closing capacity! PEEP Soft tissue injury Residual NMBD common

Question 37

Post op. Elderly

Answer 37

NSAIDs- reduce opioid Under report pain Beware cognitive impairment Fluid overload

Question 38

Triple low intraop

Answer 38

Hypotension Deep hypnotic level Low concentration volatile (don’t tolerate more) ——-all these lead to longer hospital stay and increased 1 month mortality

Question 39

When do strokes occur?

Answer 39

24hrs- 7 days

Question 40

What’s it almost impossible to do?

Answer 40

Kill a spontaneously ventilating patient