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Dr.Mohammad zwain
Anesthesia & critical care specialist
Geriatric
Anesthesia

IMPACT OF AGE-RELATED PHYSIOLOGIC
CHANGES ON ANESTHETIC CARE
▪ Aging is associated with a progressive loss of functional
reserve in all organ systems . However, there is considerable
individual variability in the onset and extent of these
changes. Nevertheless, even the healthy older adult has
reduced physiologic reserve such that organ systems may
be compromised during illness and/or surgical stress.
Physiologic changes specifically impact anesthetic care, in
part by increasing susceptibility to anesthetic drugs

▪ Nervous system — Age-related changes in the central and
peripheral nervous system result in pharmacodynamics
changes that affect older adults' responses to anesthetics
and other medications, and also affect pain perception .
Central nervous system changes include reduction in brain
size and neuronal density and widening of the sulci and
ventricles. Regional reductions in neurotransmitters (eg,
dopamine, serotonin, and acetylcholine) and neuroreceptors
may occur

▪ Decreased ventilatory responses – The normal ventilatory
responses of the central nervous system to hypercapnia,
and especially to hypoxemia, are diminished with age .
Respiratory depressant effects of opioids, benzodiazepines,
and volatile anesthetics are exaggerated, with further
impairment of responses to hypercapnia and hypoxemia .
▪ Cerebrovascular changes – Cerebrovascular autoregulation
is impaired, with diminished responses to blood pressure
changes, as well as to hypoxemia or hypercapnia .

▪ Higher pain thresholds – Changes in the peripheral nervous
system include a reduction in myelinated fibers, with
potential alterations in pain perception . Higher pain
thresholds have been observed in older patients and may
contribute to delayed presentation for painful conditions
such as acute appendicitis and peritonitis.
▪ Susceptibility to postoperative delirium – Although the
mechanisms are not clear, it is known that postoperative
central nervous system complications, particularly
postoperative delirium and postoperative cognitive deficits,
are primarily a problem in older patients . Furthermore,
undiagnosed multiinfarct dementia or neurodegenerative
disease may be present in some older patients.

Cardiovascular system — Normal changes in the older adult's
cardiovascular system such as vascular stiffening and autonomic changes
influence physiologic responses to anesthetic administration
Blood pressure lability – Labile intraoperative blood pressure (BP) is
common in older patients. Vascular stiffening renders the vascular
system less elastic leading to chronic hypertension. Episodes of
intraoperative hypotension are common in the older adult and may be
exacerbated by
▪ Vasodilatory effects of most IV and inhalation anesthetic agents
▪ Sympatholysis after placement of a neuraxial block
▪ Certain surgical techniques (eg, laparoscopic insufflation of the
abdomen causing reduced venous return)•

▪ Autonomic changes – Autonomic changes in older adults are
collectively referred to as the "dysautonomia of aging."
Impaired beta receptor responsiveness limits the ability to
increase cardiac output by increasing heart rate, so that the
patient is more reliant on vascular tone and preload.
Significant hypotension can occur when baroreflex
responsivity is compromised, particularly in the presence of
hypovolemia or underlying ventricular dysfunction.

▪ Left ventricular hypertrophy – Vascular changes increase
impedance to left ventricular (LV) outflow, causing an
increase in LV work, myocardial stiffening, and LV
hypertrophy. Impairment of diastolic filling and overt
diastolic dysfunction is present in approximately one-half of
patients older than 65 years of age with a diagnosis of
congestive heart failure . Such patients areextremely
dependent on the atrial contribution to filling during
diastole (the "atrial kick"). Thus, even brief episodes of atrial
arrhythmias during anesthesia may result in development of
significant hypotension. Furthermore, diastolic dysfunction
increases the risk of development of pulmonary edema
during fluid administration.

▪ Other cardiovascular pathology common in older patients
includes asymptomatic ischemic heart disease, calcific aortic
stenosis, fibrosis of the cardiac conductionsystem with an
increased incidence of atrial fibrillation or cardiac
conduction abnormalities, and hypertension

Respiratory system — Normal aging of the pulmonary system
that decreases overall pulmonary reserve includes
▪ Stiffening of the chest wall
▪ Decreased elasticity of lung parenchyma
▪ Increased work of breathing Increased compliance and
increased closing capacity leading to small airway closure
▪ Increased ventilation/perfusion (V/Q) mismatch R

▪ Reduced forced expiratory volume, vital capacity, and
maximal rate of oxygen consumption
▪ Increased dead space Reduction in baseline PaO , increased
alveolar-arterial gradient, susceptibility to hypoxemia
▪ Diminished ventilatory response to hypoxemia and
hypercapnia
▪ Decreased respiratory muscle strength and impaired cough
mechanism
▪ Impaired pharyngeal function

▪ Also, undiagnosed chronic obstructive pulmonary disease or
obstructive sleep apnea may be present in older patients .
Older adults are more susceptible to respiratory compromise
during monitored anesthesia care with sedation and during
the preoperative and postoperative periods.
▪ Exaggerated respiratory depressant effects of opioids,
benzodiazepines, and volatile inhalation agents increase risk
of hypercapnia, hypoxemia, apnea, and respiratory failure .
These risks are exacerbated if reversal of neuromuscular
blocking agents (NMBAs) is inadequate, particularly in
patients who are frail and more susceptible to fatigue and in
those with pulmonary comorbidities.

Hepatic system — Changes in hepatic function due to normal
aging include:
▪ Decreased hepatic mass and function, as well as decreased
hepatic blood flow, resulting in slower metabolism of most
IV anesthetic agents .
▪ Diminished albumin levels, resulting in larger free-drug
concentrations of highly protein-bound drugs such as
propofol

Renal system — Aging causes variable declines in glomerular
filtration rate, creatinine clearance, and renal functional reserve that
may be underestimated by the serum blood urea nitrogen and
creatinine alone. Comorbidities that are common in older adults
(eg, diabetes, hypertension, and vascular disease) can cause further
decline in renal function. Implications of these changes include:
▪ Increased plasma concentration of renally excreted IV agents .
Decreased ability to maximally dilute urine; thus, the older patient
has decreased ability to handle a salt or water load.
▪ Increased susceptibility to nephrotoxic effects of IV contrast or
medications such as nonsteroidal antiinflammatory drugs
(NSAIDs).

▪ Hematological system — Anemia due to iron deficiency, chronic
disease/inflammation, malnutrition, or bone marrow malfunction, is
common in older adults
▪ Pharmacokinetic changes — Decreased total body water (by 10 to 15
percent) and muscle mass result in a lower central compartment
volume result in higher initial plasma drug concentration (ie, effective
concentration) for many anesthetic agents (eg, an induction dose of
propofol) . Increased body fat (by 20 to 40 percent) also results in a
larger volume of distribution for lipid-soluble agents, with slow release
from this relatively large adipose reservoir that prolongs the clinical
drug effect . Finally, elimination half-life may be longer and clearance
may be decreased due to renal and hepatic changes, leading to
greater drug effects after repeated or continuous dosing of anesthetic
agents

PHARMACOLOGICAL CHANGES AND ANAESTHETIC
IMPLICATIONS
▪ Pharmacokinetics
▪ Changes in Distribution
▪ Around the third decade the human body starts to undergo a decrease
in total body water, a decrease in muscle mass, and an increase in
body fat. These changes occur at about 1% per year, and by the age of
65, 25–30% of muscle may be lost and replaced by fat tissue. Total
body water at this age also decreases to a similar degree.
▪ These changes in body composition may influence the volume of
distribution for certain drugs.A decrease in water content leads to
reduction in initial volume of distribution of water-soluble drugs. As a
result, blood levels for a given drug dose are higher in the elderly,
causing a greater brain concentration and resulting in a greater effect.

▪ There is reduced receptor number, increased receptor
sensitivity and postreceptor transduction in the brain.
Hence, geriatric patients have increased sensitivity to
anaesthetic drugs. Hepatic metabolism and renal drug
clearance is also affected. There is rapid equilibration with
the peripheral compartment due to decreased total body
water, and hence less dose of drug is required. In the central
compartment, there is decreased lean body mass and
albumin, causing raised peak concentration and slower
redistribution. Increased body fat accounts for slow
equilibration leading to prolonged drug actions

▪ Increases in total body fat may prolong the elimination half-life for
lipid-soluble drugs. With an increase in adipose tissue, drugs
accumulate more extensively in fat, thereby increasing the volume of
distribution. A larger volume of distribution ( V d ) increases the
metabolic half-life by making less drug available in the blood ( t 1/2 ~ V
d / Clearance, where Clearance is the volume of blood from which
drug is eliminated on a per-time unit basis). This phenomenon is
especially applicable to lipophilic drugs such as the benzodiazepines
and many of the opioids such as the fentanyl family (except
remifentanil).
▪ Curiously, with extreme age and frailty, total body fat typically declines
and therefore the volume of distribution for lipophilic drugs may
decrease. In theory, metabolic half-life would therefore decrease
(faster elimination), but only if clearance did not change with age.

Changes in Metabolism
▪ As might be expected, drug elimination typically does decrease with age. Both
drug metabolism by the liver and drug excretion by the kidneys decrease, even
in healthy elderly. The liver mass in a patient of advanced age can decrease by
20–40% and is accompanied by a 35% decrease in hepatic blood fl ow.
▪ The rate of glomerular fi ltration also decreases ~10% per decade after age 50
and is accompanied with a loss of renal parenchyma. It is important to
remember that decline in renal function may not be reflected by creatinine
levels due to a reduction in muscle mass and a corresponding decrease in
creatinine production. Thus, the decrease in clearance and the increase in the
volume of distribution conspire to slow drug metabolism in the elderly patient.
The magnitude of the decrease in metabolism can be dramatic. For example,
diazepam has a half-life in hours that is approximately equal to the patient’s
age, meaning that a 72-year-old patient has a metabolic half-life for diazepam
of ~3 days.

Changes in Protein Binding
▪ Healthy elderly may experience decrease in albumin levels up to
10%, but it may decrease more in frail and malnourished
individuals. But not all the proteins decrease with advanced age;
a 1-acid glycoprotein may increase, possibly due to an underlying
in fl ammatory processes. However, in general, protein binding
decreases in the elderly. Since only protein-unbound drugs
produce tissue effects, a decrease in protein binding increases
the amount of active drug, reducing the necessary drug dose.
This is particularly true regarding the drugs that undergo liver
metabolism, are highly protein bound, and are administered
intravenously, for example, lidocaine, fentanyl, and midazolam.

▪ Pharmacodynamics
▪ Receptor Changes
▪ Age is associated with a decrease in the number of m – and k –opioid receptors.
This change may be related to memory impairment in healthy elderly. Number of
dopaminergic neurons and dopamine D 2 receptors also declines. GABA(A)
receptors not only decrease in number, but also undergo changes in composition
with loss of presynaptic GABA release. That may explain the increase in sensitivity
to benzodiazepines with advanced age. Other CNS receptors that decrease in
number and/or in binding with age include cholinergic (nicotinic and muscarinic)
and N –methyl- d aspartate (NMDA) receptors. Receptor changes outside the CNS
also include downregulation of b –adrenoceptors and diminished responsiveness
of adenosine A-1 receptors that carry out cardioprotective effect. Though the
clinical signi fi cance of the receptor-related alterations is not completely clear,
they may explain why elderly require less anesthetic agents to produce the desired
end-organ effect.

PREANESTHESIA CONSULTATION
▪ Assessment for frailty — Frailty in older patients is defined
as an aging-related syndrome of physiologic decline and
reduced tolerance to medical and surgical interventions .
Frail older patients often present with an increased burden
of symptoms including weaknessand fatigue, medical
complexity, and a decrease in physiologic reserve that may
exceed that expected from advanced age alone . Frailty
predicts postoperative mortality and morbidity including
delirium or cognitive impairment, as well as longer hospital
stay, discharge to a skilled nursing facility, and long-term
functional decline

▪ Estimates of the prevalence of frailty are approximately in 30
percent in older patients (mean age 70 years) undergoing
nononcologic surgery, and may be as high as 50 percent in
older patients who require cancer surgery , and is common
in critically ill surgical patients . Identification of frailty in the
preoperative period can be helpful to inform patient and
family discussions regarding surgical techniques,
postoperative recovery strategies, and likely outcomes

▪ In some cases, such discussions include a decision
regarding whether or not the surgical procedure is
appropriate due to adverse impact on quality of life, and/or
consideration of a palliative care consultation . It has been
suggested but not yet proven that surgical outcomes may
be improved in some older frail patients by optimizing
preoperative condition and improving physiologic reserve
with a prehabilitation program that may include smoking
cessation, as well as exercise training, nutritional
supplementation, and a multidisciplinary approach to
postoperative care and discharge planning that includes a
geriatrician

Geriatric Anest hesia.pptx

▪ Rapid frailty screening tools have also been used in the perioperative
setting. One example is the FRAIL scale, a verbal assessment that takes only
minutes to perform, evaluates Fatigue; Resistance (difficulty climbing stairs);
Ambulation (difficulty walking one block); Illnesses that include
hypertension, congestive heart failure, angina, asthma, arthritis, stroke, and
kidney disease; and weight Loss . Perhaps the most rapid assessment is the
CFS based on self-reporting of comorbidities and the need for help with
activities of daily living (ADLs) .
▪ This simple screening tool may have advantages for routine preoperative
clinical assessment because it incorporates activity levels (between 1 [very
fit] and 7 [severely frail]) with medical conditions and other elements.
Despite the availability of these rapid tools, preoperative frailty screening is
not routinely performed in many centers due to lack of agreement on which
tool is optimal, and difficulty with implementing additional assessments
into busy clinical practices.

▪ Assessment of baseline cognitive function — The ASA Brain
Health Initiative guidelines suggest that baseline cognition
should be evaluated in patients olderthan 65 years,
particularly those with risk factors for preexisting cognitive
impairment . Older patients should be informed of risks for
postoperative neurocognitive disorder (eg, confusion,
inattention, and/or memory problems) . However, these
effects of anesthesia and surgery are usually temporary.

▪ Medication history — Obtaining an accurate medication
history, including both prescription and over-the-counter
medications, may require extra effort since older adult
patients often forget or confuse their medication regimen
The incidence of adverse drug-related events is high in older
patients taking multiple medications (polypharmacy) . Thus,
the opportunity for reconciliation of the medication
schedule is one distinct benefit of a scheduled patient visit
to the preoperative clinic [91].

Examples of medications commonly used by older patients that are
potentially relevant for anesthetic care include :
▪ Antiplatelet agents or oral anticoagulants must be managed if a
neuraxial anesthetic is planned.
▪ Angiotensin-converting enzyme (ACE) inhibitors or angiotensin II
receptor blockers (ARBs) administered within 12 hours of anesthetic
induction are associated with increased risk of intraoperative
hypotension. In many centers, ACE inhibitors and ARBs are held for
a period of 24 hours prior to surgery or are administered the
evening dose before surgery (and not on the morning of surgery),
▪ Benzodiazepines are minimized or avoided as they are associated
with increased risk of perioperative delirium [92].

PREOPERATIVE TESTING
▪ Routine preoperative testing is not recommended before
minor procedures in older adults. In a prospective
randomized trial that included more than 18,000 older
patients having cataract surgery, no differences in
complications were noted in those who received routine
preoperative testing (complete blood count, and
measurement of serum levels of electrolytes, urea nitrogen,
creatinine, and glucose) compared with those who received
tests only if indicated by medical condition(s)

▪ ECG – An electrocardiogram (ECG) for patients with coronary heart
disease, significant arrhythmia, peripheral arterial disease,
cerebrovascular disease, or other significant structural heart disease
and known cardiovascular risk factors undergoing intermediate or high
cardiac risk surgery is reasonable
▪ Age alone is not an indication for ECG , although some institutions had
historical guidelines recommending a preoperative ECG in adult
patients older than 55 years. These guidelines were based on the
observation that older patients have a high incidence of preoperative
changes on the ECG , despite data showing little predictive value of the
preoperative ECG Rather, a higher ASA score (>3) as an indication of the
presence and severity of comorbidities, as well as a history of chronic
heart failure, were significant predictors of postoperative cardiac
complications in this study .

▪ Chest radiograph (CXR) – In general, a preoperative chest
radiograph (CXR) is unnecessary for older patients
undergoing elective non-thoracic surgery . In patients with
symptomatic cardiac or pulmonary disease, a CXR may be
obtained before high-risk surgery if not performed within
the past six months.

▪ Laboratory tests – There is no consensus on the specifics of routine
testing in older patients.Hemoglobin and hematocrit are not routinely
recommended . but are typically obtained before major surgical
procedures with significant expected blood loss (eg, procedures with
>10 percent chance of needing a transfusion or >500 mL blood loss),
and in individuals likely to have preoperative anemia due to a known
underlying condition. Depending on the cause and degree of anemia,
the urgency of the procedure, and the expected amount of blood loss
and other risk factors, surgery may be postponed to diagnose the
cause and correct anemia when feasible
▪ Preoperative creatinine and albumin may be measured before
moderate- or high-risk surgery in frail older patients or those with a
known history of liver disease or chronic illness since these patients
have a relatively high incidence of renal dysfunction and malnutrition

▪ Other screening tests – Other screening tests (eg,
echocardiography, pulmonary function testing) are ordered
according to criteria used for adult patients of any age since
there are no data demonstrating that routine use of such
testing is useful to predict or manage postoperative
complications in older adults

ANESTHETIC TECHNIQUES
▪ Neuraxial versus general anesthesia — Choice of neuraxial
or another regional anesthetic should be guided by the
requirements of the surgical procedure, coexisting
disease(s), the need to prevent postoperative complications,
and patient preferences . Although the results are not
consistent, some studies have noted that neuraxial or other
regional anesthetic techniques may reduce pulmonary
complications and need for postoperative mechanical
ventilation compared with general anesthesia, particularly in
older patients with chronic obstructive pulmonary disease

▪ However, general anesthesia may be preferable in the following clinical
scenarios :
▪ Patients receiving anticoagulant or antiplatelet medication or with
coagulopathy due to other reasons, such that neuraxial anesthesia and
deep peripheral nerve blocks are relatively contraindicated. (
▪ Patients with decreased cardiac preload (eg, due to hypovolemia or
expected major blood loss) that would be exacerbated by sympathetic
blockade with resultant severe hypotension.
▪ Requirement for deep sedation due to patient inability to lie comfortably in
the position necessary for surgery.
▪ Anxiety, reluctance to be awake, or inability to cooperate or communicate
(eg, due to dementia). Anticipated prolonged duration of a surgical
●
procedure.

▪ Monitored anesthesia care with sedation — A monitored
anesthesia care technique is often selected for older adults
who require a diagnostic or therapeutic procedure,
especially in remote locations such as endoscopic
gastrointestinal or interventional radiology suites
▪ During monitored anesthesia care, short-acting agents are
administered to provide analgesia, sedation, and anxiolysis
as necessary; however, excessive anesthetic depth is
avoided, and rapid recovery is desired. Notably, progression
from a “light” level of sedation to “deep” sedation (or
unconsciousness) is not uncommon and may occur rather
suddenly

INTRAOPERATIVE MANAGEMENT
▪ Selection and dosing of anesthetic agents
▪ Propofol – Older adult patients have an altered
pharmacodynamic response to propofol. As judged by the
electroencephalography (EEG), older subjects are approximately
30 percent more sensitive to its effects . In addition, clearance of
propofol is decreased .
▪ The initial induction dose of propofol and subsequent bolus
doses should be reduced by 40 to 50 percent to 1 mg/kg to 1.75
mg/kg, and should be slowly administered . Similarly,
maintenance doses during an ongoing infusion of propofol
must be decreased by 30 to 50 percent, in order to avoid a
doubling of recovery time

▪ Ketamine – Ketamine is rarely used for anesthetic induction
in older patients because of its unique cardiovascular effects
(increases in blood pressure and heart rate due to a
centrally-mediated sympathetic response), as well as the
undesirable side effect of postoperative delirium [18,123].
However, ketamine may be selected for those with
hemodynamic compromise caused by hypovolemia or
cardiomyopathy in the absence of coronary artery disease.
Also, since ketamine is a bronchial smooth muscle relaxant,
it may be useful in older patients with reactive airway
disease.

▪ Opioids – All opioids are approximately twice as potent in older patients. Also,
since opioids have the potential to cause respiratory depression, the
increased brain sensitivity and decreased clearance of opioids in older
patients can result in severe hypoventilation or apnea .
▪ Short-acting opioids – For fentanyl, sufentanil, and alfentanil, respiratory
depression is primarily a pharmacodynamic effect due to age-related
increased brain sensitivity to opioids . For remifentanil, there are also changes
in pharmacokinetics due to decreased volume of the central compartment
and decreased clearance, so that only half of the bolus dose is required.
▪ Long-acting opioids – For morphine, the volume of distribution is increased in
older adults, and renal clearance is reduced for the parent drug, as well as its
active metabolite, morphine-6-glucuronide . Thus, there is an enhanced
analgesic effect and prolonged duration of action after each dose of
morphine. Clearance is further reduced in patients with renal insufficiency.

▪ Medications to avoid or
use with caution

▪ Inhalation anesthetic agents — The minimum alveolar
concentration (MAC) at 1atmosphere preventing movement
in 50 percent of patients exposed to a surgical incision of all
inhalation agents decreases by approximately 6 percent per
decade after age 40 years . By age 90 years, MAC is reduced
by 30 percent . Similarly, the anesthetic requirement to
produce unconsciousness (ie, absence of response to
commands [MACawake] is decreased with age). Although
reasons for age-related decline in MAC andMACawake are
not fully understood, likely mechanisms include a
combination ofage-related effects on synaptic activity and
neurotransmitter function in the brain, cerebral atrophy,
and changes in cerebral circulation

▪ Neuromuscular blocking agents — Notably, various neuromuscular
blockingagents (NMBAs), including succinylcholine, may have a prolonged
onset time as well as a prolonged duration in older patients. Likely
mechanisms include decreased muscle blood flow and decreased cardiac
output . In general, we use NMBAs sparingly when possible. Shorter-
acting NMBAs are typically selected because age-related reductions in
hepatic metabolism and renal excretion may result in prolonged duration
of action for certain agents (eg, vecuronium, rocuronium) .
▪ However, age has little effect on NMBAs eliminated by other means, such
as ester hydrolysis and Hoffmann degradation (eg, atracurium,
mivacurium, and cisatracurium). Notably, recovery of muscle function
after administration of sugammadex, which facilitates rapid reversal from
neuromuscular blockade induced by rocuronium, is slower in older
patients

▪ Fluid management — The overall goals of intraoperative fluid
management are to avoid dehydration, maintain an effective
circulating volume, and prevent inadequate tissue perfusion [132].
Optimal fluid management has been a challenging area of research
in the general surgical population, particularly in older patients.
Little to no generalizable evidence exists to guide therapy. Clinical
judgment based upon available measures of volume status and
tissue perfusion is the most important factor.
▪ Fluid management in older patients with heart failure can be
especially challenging. IV fluid restriction may not prevent the
development of heart failure. In fact, reducing the effective
circulating volume may have a negative effect upon cardiac function
since adequate preload is necessary for myocardial contractility

▪ Hemodynamic management — As noted above, changes in
the older adult's cardiovascular system such as vascular
stiffening and autonomic changes may lead to
hemodynamic instability during anesthesia and surgery . In
particular, periods of intraoperative hypotension may
contribute to adverse cardiac events in older patients . Some
require an intraoperative mean arterial pressure target
higher than the typically targeted 65 mmHg, particularly
those with chronic hypertension
▪ Avoidance of hypothermia — Perioperative hypothermia is
more frequent, pronounced, and prolonged in older adults,
who have compromised ability to quickly regain
thermoregulatory control .

Positioning — The skin, muscle, and joints atrophy and
degenerate in aging. Older adults are more susceptible to
trauma from positioning and adhesives. Osteoarthritis is
common in older adults, and arthritic joints can lead to
positioning difficulty or injuries. Care must be taken during
positioning to ensure adequate padding of pressure points
and support of joints. In addition, degenerative cervical spine
disease can limit neck extension, potentially making
intubation difficult.

▪ Ventilation Strategies
▪ Older adults have an increase in residual volume and overall decrease
in vital capacity.32 Aging is also associated with alveolar airspace
disease, increased closing capacity, and reduced functional residual
capacity (FRC) leading to atelectasis, pulmonary shunting, and
hypoxemia.
▪ Prolonged preoxygenation, adequate mask ventilation, and positive
end-expiratory pressure should be utilized to reduce the risk of
hypoxia.
▪ Common intraoperative maneuvers, such asincreased intra-abdominal
pressure due to carbon dioxide insufflation or Trendelenburg
positioning, further reduce the FRC and lung compliance.

▪ Older adults also have decreased respiratory muscle strength and
protective reflexes, predisposing them to aspiration and postoperative
pneumonia.
▪ Older adults have increased risk of postoperative respiratory depression
due to decreased respiratory drive response to hypoxia and hypercarbia
and increased prevalence of OSA.
▪ Lung protective strategies are recommended in patients with risk factors
for postoperative pulmonary complications. defined as low tidal volumes
(<10 mL/kg), adequate positive end-expiratory pressure (PEEP) ( 5
≥
cmH2O), and plateau pressures <30 cmH2O, were significantly associated
with reduced postoperative pulmonary complications. A PEEP of 5 cmH2O
and plateau pressures of less than or equal to 16 cmH2O were associated
with the lowest risk of postoperative pulmonary complications.

POSTOPERATIVE PAIN MANAGEMENT
▪ Although there is an age-related decrease in pain perception, postoperative
analgesia is a critical aspect of perioperative anesthetic care for the older
patient . Although opioids may precipitate or worsen delirium, inadequate
pain relief is also associated with a greater likelihood of delirium and
subsequent morbidity in older patients . To reduce the risk of delirium and
other opioid-related side effects, we employ a multimodal approach to pain
management
▪ Management begins with careful assessment of postoperative pain, which
may be challenging in older patients with some degree of chronic pain, or
extremely difficult in those with mental status changes . Although numerical
verbal pain scales are superior to nonverbal methods of assessment,
cognitively impaired patients may not understand these scales . Patients
with advanced dementia and those who are nonverbal may respond best to
visual analog scales that use faces expressing pain and sadness.

▪ For mild postoperative pain, acetaminophen 650 to 1000 mg
administered every six hours is the nonopioid of choice,
unless contraindicated due to hepatic disease. The addition
of scheduled acetaminophen to a morphine patient-
controlled analgesia (PCA) results in improved pain scores
and lower overall opioid doses in some patients .
Intravenous (IV) acetaminophen may be used in patients in
whom oral or rectal administration is not an option.

▪ Other nonopioid alternatives include nonsteroidal anti-
inflammatory drugs (NSAIDs), such as ketorolac . However,
NSAIDs carry a significant risk of transient platelet
dysfunction and bleeding, as well as gastrointestinal
hemorrhage and renal insufficiency. Thus, the dose of
ketorolac should be reduced to 15 mgevery six hours in
older patients, with no more than 60 mg administered in a
24 hour period . For selected patients, continuous epidural
analgesia is appropriate as the planned primary method for
controlling pain . Peripheral nerve blocks and adjuvant
techniques such as local anesthetic infiltration are also
commonly used to reduce the need for systemic opioids.

▪ If systemic opioids are necessary for pain control in the
immediate postoperative period, doses are reduced .
Notably, initial titration of opioids to successfully control
pain in older patients requires extra time and may
necessitate a longer stay in the post-anesthesia care unit . If
additional IV opioid doses are needed after initial titration,
PCA should be implemented . If delirium or other factors
preclude use of PCA, regularly scheduled age-adjusted
opioid dosing is an option. Subcutaneous administration
may be employed when no reasonable alternatives exist,
but absorption may be erratic or inadequate in older adults
with edema or regional hypoperfusion.

OUTCOMES
▪ Mortality
▪ Older age is a risk factor for perioperative mortality, but
preoperative comorbidity, frailty, an d invasiveness of the
surgical procedure, recent need for hospitalization, high
American Society of Anesthesiologists (ASA) score , and a
preexisting diagnosis of heart failure
▪ Pulmonary complications – Even healthy older patients have
a substantial risk of pulmonary complications after surgery
[25] (see “Evaluation of perioperative pulmonary risk”). The
most important complications are atelectasis, pneumonia,
respiratory failure, and exacerbation of underlying chronic
lung disease.

▪ Cardiac complications – Advanced age has not been
definitively proven to independently increase perioperative
risk for postoperative cardiac death or major cardiac
complications, including nonfatal myocardial infarction and
heart failure. Age is noted as a minor risk factor in the 2014
American College ofCardiology/American Heart Association
(ACC/AHA) perioperative guidelines, since perioperative
myocardial infarction confers a higher mortality in
older adults
●
▪ Acute kidney injury – Risk for development of acute kidney
injury, defined as an increase in serum creatinine of at least
2 mg/dL or acute renal failure requiring dialysis, is increased
in older patients

▪ Delirium – Advanced age is a risk factor for perioperative
neurocognitive disorder (NCD) . In particular, postoperative
delirium is common in older adults undergoing major
surgery (ranging from 4 to 55 percent), with the highest
incidence occurring after emergency, cardiac, or major
orthopedic surgery . Notably, up to 40 percent of older
adults who develop postoperative delirium never return to
their preoperative cognitivebaseline

▪ Recovery
▪ Functional recovery – Functional recovery after surgery (ie,
for activities of daily living and independent activities of
daily living) is highly variable in older adults. Factors
influencing recovery include preoperative physical
conditioning, depression, and serious postoperative
complications. On average, following major abdominal
surgery, recovery to preoperative levels of function may
require three to six months

▪ Hospital readmission – In a large Medicare database study
that included more than 560,000 patients, the rate of
admission to an inpatient hospital within 30 days after
outpatient surgery was significantly higher in patients 80
≥
years of age . In another Medicare database study that
included approximately 160,000 patients undergoing
inpatient surgery, the readmission rate was 8 percent in
those without a preexisting diagnosis of heart disease, 11
percent for patients with a prior diagnosis of coronary artery
disease, and 17 percent for those with a prior diagnosis of
heart failure

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Geriatric Anest hesia.pptx

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