geriatric anaesthetic management

1. GERIATRIC
ANAESTHESIA
Dr. Radhwan Hazem Alkhashab
Consultant anaesthesiologist & intensivist
2022

2. Introduction
 Due to physiologic and pathologic changes that occur with
age, these patients are at higher risk of perioperative
morbidity and mortality.
 People over 65 years of age are 3.5 times more likely to
have surgery.
 Aging results in a progressive decline in the functional
reserve of all organs; the rate at which function diminishes
is highly variable between individuals.

3. Aging is a progressive physiologic process
characterized by :
1- Decreased functional capacity.
2- Increasing incidence of pathologic processes.

4. PathophysiologyOfAgingBySystem
Cardiovascular
1. Decreased arterial elasticity:
• Increased afterload
• Left ventricular hypertrophy
• Increased systolic blood pressure, mean arterial pressure, and pulse
pressure
2. Autonomic imbalance:
• Increased vagal tone
• Decreased sensitivity of adrenergic receptors
• Decreased baroreceptor reflex

5. 3. Fibrosis of the conducting system and loss of sinoatrial
node cells .
4. Sclerosis calcification of valves.
5. High incidence of diastolic dysfunction
6. Atherosclerosis and increased arterial wall thickness.
7. Maximal heart rate and cardiac output also decrease with age.
8. Autoregulation of blood flow to kidney and brain is reduced.

6. Respiratory changes
1. Alterations in control of respiration, lung structure, mechanics, and
pulmonary blood flow place elderly patients at increased risk for
perioperative pulmonary complications.
2. Ventilatory responses to hypoxia & hypercapnia are impaired
secondary to reduced central nervous system activity.
3. In addition, the respiratory depressant effects of benzodiazepines,
opioids, and volatile anesthetics are exaggerated.
4. Functional capacities of the respiratory system are all reduced

7. Otherchanges
5. Increased V/Q mismatch.
6. Increased chest wall rigidity leading to increased work of breathing.
7. Decreased protective reflexes (coughing and swallowing) increasing
the risk for aspiration.
8. Increased pulmonary vascular resistance and pulmonary arterial
pressure.
9. Blunted hypoxic pulmonary vasoconstrictive response.

8. Cont.
10. Loss of elastic elements within the lung is associated
with enlargement of the respiratory bronchioles and
alveolar ducts, and a tendency for early collapse of the
small airways on exhalation.
11. Residual volume increases by 5% to 10% per decade.
Vital capacity decreases. Closing capacity increases with
age.

9. NormalPaO2

10. Renal
Decreased renal mass : Renal mass may decrease 30% by age 80
years. Loss of mass is most prominent in the renal cortex. This loss
correlates with a decrease in the number of functioning glomeruli.
• Progressive decline in creatinine clearance.
• Increased risk of perioperative acute renal failure.
Decreased renal blood flow:
• Serum creatinine unchanged due to loss of muscle mass.

11. Decreased tubular function:
 Altered sodium balance, urine concentrating ability. and
drug excretion
 Increased risk for dehydration and electrolyte
abnormalities.
 Decreased renin-aldosterone system resulting in
impaired potassium excretion.

12. Neurologicchanges
 Decrease in the volume of gray and white matter.
 Decreases in brain reserve are manifested by :
1. Increased sensitivity to anesthetic medications.
2. Increased risk for perioperative delirium and postoperative
cognitive dysfunction.
 Decreased neurotransmitter synthesis: GABA, serotonin, dopamine,
norepinephrine, and acetylcholine system .
 Variable degrees of cognitive function decline, especially short-term
memory.
 Decreased general anesthesia (MAC and local anesthetic
requirement.

13. Neuroaxialchanges
1. Reduction of the area of the epidural space.
2. Decreased volume of CSF.
3. The diameter and number of myelinated fibers in the
dorsal and ventral nerve roots are decreased.
4. Decreased conduction velocity in peripheral nerves.
These changes tend to make elderly individuals more
sensitive to neuroaxial block.

14. Hepaticchanges
1. Liver volume decreases approximately 20% to 40%
with aging.
2. Hepatic blood flow decreases about 10% per decade.
3. There also is a variable decrease in the liver's intrinsic
capacity to metabolize drugs.
4. Effects on phase I reactions predominate.
5. Decreases in hepatic blood flow may decrease
maintenance dose requirements in drugs that are
rapidly metabolized by liver.

15. Musculoskeletalchanges
1. Reduced muscle mass; atrophic skin; frail veins.
2. Increased body fat.
3. Total body water decreases.
4. Arthritis can affect various joints that can complicate
positioning.
5. Degenerative changes of the cervical spine; intubation
potentially more difficult.

16. Endocrine/metabolic
I. Atrophy of endocrine glands leading to impaired
hormone function: Insulin, thyroxine, growth hormone,
testosterone.
II. Blunted neuroendocrine stress response.
III. Decreased heat production and alteration in
hypothalamic temperature-regulating center.

17. Nutrition
 Poor nutrition status is common in the geriatric patients.
A meta-analysis presented that perioperative oral
nutritional supplementation had a positive effect on
serum total protein and led to fewer complications, but
did not have a positive effect on postoperative mortality.
Prolonged preoperative fasting should be avoided in this
population.

18. Age-relatedpharmacologiceffects
i. Increased body fat and decreased total body water.
ii. Higher plasma concentration of water-soluble drugs.
iii. Lower plasma concentration of fat-soluble drugs.
iv. Reduced clearance secondary to decreased hepatic
and renal function.

19. Alteredproteinbinding:
 Reduced albumin affects binding of acidic drugs
(opioids. barbiturates, benzodiazepines).
 Drug effects may be intensified due to decreased
number of available receptors .
 Reduced anesthetic requirement (or Mac).

20. Pharmacokineticandpharmacodynamic
 Response to induction agents results in exaggerated effect
on blood pressure.
 There is also a reduced response to atropine. Moreover,
diminished responses to hypovolemia are supplementary
confounded by volatile anesthetics and the sedative drugs
that impair baroreflex control mechanisms

21. PreoperativeEvaluation
 Perform a thorough history and physical examination
(based on clinical correlate) .
 Assess optimization of preexisting conditions such as
CAD, hypertension, or diabetes .
 Review medication history as polypharmacy is common
among the elderly, increasing the risk of medication
interaction.
 Oxygen desaturation and hypoxemia happens faster in
the geriatric patients. Hence, appropriate
preoxygenation is critical.

22. Note
 Irrespective of the type of anesthetic techniques,
anesthesia should be performed by experienced
anesthesiologists who are qualified to accomplish the
perioperative care of geriatric patients.
 In a recent review, there might be benefits to selecting
regional versus general anesthesia as a primary
anesthetic modality in certain patient groups.

23. Intraoperativemanagement
 Monitoring based on procedure type and underlying
organ involvement.
 Careful titration of anesthetic agents with cardiac- and
respiratory- depressant effects.
 Careful attention toward fluid management to avoid fluid
overload; at the same time maintain adequate
hydration/tissue perfusion.
 Age-related respiratory effects as well as coexisting
pulmonary disease may necessitate vigorous
preoxygenation.
 Avoid hypothermia.

24. Regionalanesthesiaisareasonablechoice:
 Regional anesthesia (RA) may have some benefits over
general anesthesia, including less thromboembolic
events, confusion and respiratory problems
postoperatively.
 Reduce local anesthetic dose for spinal anesthesia by
40%. ( due to possiblilty of Increase risk of hypotension).

25.  Peripheral blocks in the geriatric patients demonstrate
satisfactory outcomes without compromising the safety
of the airway or risking major hemodynamic effects.
However, there are some anatomical changes including
weakening of spine and intervertebral disks, fibrosis of
intervertebral foramina, and reduction in fat in epidural
space in these patients.

26. Age-relatedEffectsOnAnestheticAgents

28. PostoperativeManagement
 Optimal pain management to improve respiratory effort,
prevent delirium, and promote early ambulation.
 Higher incidence of perioperative complications in the
elderly due to age-related physiologic changes as well
as associated comorbidities:
1. Infection.
2. Thromboembolism.
3. Respiratory: most common morbidity.

29. 4. Cardiovascular: MI and cardiac arrest more common
in elderly.
5. Stroke: risk factors are age, atrial fibrillation, and
history of previous stroke.
6. Postoperative confusion, delirium, or cognitive
dysfunction common in elderly.