Chapter 58 Geriatric Pain Flashcards
Practitioners should be guided by two overarching principles when evaluating
the older adult with pain.
First, the rules of multiplicity rather than Occam’s razor should drive the assessment of the causes and contributors to pain. That is, pain should be
conceptualized as a syndrome potentially “caused by a multiplicity of pathologies in multiple organ systems. The second principle follows in that the symptom with which a patient presents may represent the
weakest link, but not necessarily the treatment target
Low back pain in older adults commonly contributed to by
hip osteoarthritis, fibromyalgia syndrome, and myofascial pain
Myofascial pain may be contributed to by
axial spondylosis, degenerative scoliosis, leg length discrepancy, and anxiety
pain may present subtly as
loss of function, or change in mood or cognition
Treatment may require targeting
biomechanics, insomnia, depression, and/or other
long-standing chronic disease often coexisting with persistent pain to optimize function and quality of life
Older patients with persistent pain conditions should be screened routinely for
concurrent mental health conditions (e.g., depression, anxiety, and dementia). Failure to treat comorbid psychiatric illness will likely result in ineffective analgesia
Other diseases common in older adults that may cause or exacerbate pain include
osteoporosis and osteoarthritis, diabetes, cancer, cardiovascular disease, and dementia.
Alzheimer’s disease (AD) may pose a significant
challenge to the treating practitioner for a number of reasons:
(1) Patients with AD may have difficulty communicating their pain. (2) Anxiety/fear of pain may amplify the experience and expression of pain in patients with AD,
thus the most appropriate treatment may be uncertain.
(3) Patients with AD may perseverate on, but not suffer from, their pain, thus use of pain self-report as the gold standard
for guiding treatment becomes complicated.
(4) As dementia progresses, patients with AD may lose treatment
expectancy that may compromise analgesic efficacy.
Risk factors for the development of disability include
high burden of medical comorbidities, depression, sensory impairments related to vision and hearing, and musculoskeletal disorders such as arthritis. Smoking, level of alcohol use, inactivity, and lack of social support also contribute significantly
morphologic and functional changes in the peripheral and central nervous system that may impact pain processing
decline in the number of myelinated and unmyelinated fibers, an increase in the number of damaged nerve fibers, slowed nerve conduction velocity, loss of serotonergic and noradrenergic neurons in the dorsal horn, and a reduction in serotonergic receptor density in the anterior cingulate and prefrontal cortex, among others
Neuropsychological performance (NP)
declines with age and brain volume loss, senile plaques, and neurofibrillary tangles occur in the absence of AD. Persistent pain itself is associated with deterioration of NP and evidence indicates that pain reduction is associated with improved NP
Because provider–patient communication is an essential component in the treatment of pain
impairments in vision and hearing may alter treatment efficacy and require modified assessments. Vision and hearing change both structurally and functionally with age
Common eye diseases
cataract, glaucoma, macular degeneration, and
diabetic retinopathy) associated with aging may result in moderate to severe vision loss
Presbycusis
loss of hearing with age. Assistive technologies such as hearing aids and a frequency modulation (FM) device for those patients with speech
recognition difficulty, may be helpful when practitioners evaluate these patients, as they afford the opportunity to engage in more meaningful conversation and improved care
Postural control abnormalities leading to
increased risk of falls. pain adds to this risk. assessment of balance should be a routine part of assessing the older adult with pain.
Common changes in the musculoskeletal system include
sarcopenia (i.e., progressive loss of lean body mass associated with muscle cell atrophy and infiltration of fat), degenerative arthritis, and decreased bone density. Pain practitioners need to be acutely aware of the fact that radiographic evidence of degeneration without pain is exceedingly common
Management of changes in the musculoskeletal system
Over half of older adults with radiographic evidence of hip osteoarthritis (OA) are without hip pain. Thus, the history and physical examination should provide strong evidence of disease before imaging is ordered to avoid unnecessary procedures such as injections and surgery that carry the potential for morbidity.
majority of older adults with chronic low back with or without leg pain have a combination of pathologies responsible for their symptoms. Ex
hip OA, fibromyalgia, iliotibial band pain
Vertebral compression
fractures
occur in the absence of acute pain, but
as kyphosis develops, they may contribute to pain in the upper and lower back
vitamin D deficiency
common in older adults and may contribute to muscular pain and falls. Assessment of serum 25-OH vitamin D may be considered as part of pain
assessment in older adults and correction of insufficiency a routine part of treatment.
Pharmacokinetics
Absorption
Remains unchanged
Increase Gastric pH
Decrease Secretory capacity and GI blood flow
Pharmacokinetics
Distribution
Decrease Plasma albumin, Protein affinity, Total body water
Increase alpha 1-acid glycoprotein, Expression and activity of
P-glycoprotein in live
Pharmacokinetics
Metabolism
Decrease Liver volume, Hepatic blood flow, First-pass metabolism, Phase I metabolism, Phase II metabolism in frail
Increase Interindividual variability with age
Pharmacokinetics
Elimination
Measurable and predictable decline
in renal function with age
Decrease Glomerular filtration rate and Renal plasma flow
Body Composition
Increase Body fat
Decrease Lean and total body mass
Central Nervous System
Decrease Blood supply to brain and Baroreceptor activity
Cardiovascular Function
Decrease Resting heart rate, stroke volume, and cardiac output
Renin-Angiotensin-
Aldosterone System
Decrease Plasma renin and Urine aldosterone
Medications that have a high hepatic extraction ratio may undergo
decreased clearance and experience a longer half life in older adults because of diminished liver size and blood flow
Meperidine and Morphine use in older patient
Meperidine (contraindicated in older adults because of its renally cleared active metabolite that can
cause seizures) and morphine are high extraction ratio analgesics whose first-pass effect and clearance is reduced with age.
long half-life nonsteroidal antiinflammatory drugs are hepatically metabolized and their clearance may be reduced in older adults:
celecoxib, diflunisal,
naproxen, oxaprozin, prioxican, salsalate, and sulindac
Analgesics that are affected by aging-associated decline in
renal function include
codeine, duloxetine, gabapentin, meperidine,
pregabalin, propoxyphene, salicylate, tramadol,
and the opioids morphine, oxycodone, hydromorphone,
fentanyl, and methadone
Cockcroft-Gault equation,
shown below, to estimate creatinine clearance
(CrCl) that helps to guide dose adjustment of renally cleared medications
CrCl = ( (140 ¬- age) * (Wt in kg) * (0.85 if female)) /
72 *Cr
Pharmacodynamics refers to
tissue sensitivity and how a drug interacts with its end organ. The body’s response to
medications may be therapeutic or adverse
Opioid sensitivity increases with associated decline
in mu opioid receptor density and increase in
opioid affinity. Thus older adults may respond to opioid doses that are significantly smaller than those in younger individuals.
The purpose of pain assessment is twofold:
(1) to identify contributors to pain that are usually multiple, and (2) to identify outcome measures to follow during the course of treatment, that is, each patient’s individual “pain signature
Pain assessment in older adults
Pain assessment should be an ongoing process to measure change in pain over time as this will affect any necessary modifications in the treatment course. Assessment of pain alone is not sufficient; providers should inquire about changes in appetite, sleep, and/or mood, loss of mobility, and diminished activity level.
indicative of an acute
pain event
Abnormalities in traditional vital signs such as abrupt changes in respiratory rate or heart rate
For cognitively intact older adults, there are many pain rating tools from which to choose
Numeric rating scales (NRS) and verbal descriptor scales (VDS)
Medication that enhance fall risk
opioids, tricyclic antidepressants, gabapentin, and pregabalin
How to manage patient who are taking Medication that enhance fall risk
it is prudent to optimize mobility (e.g., by referring the patient to a physiatrist or physical therapist for instruction in using the appropriate assistive device and gait/balance training) prior to prescribing medications that may further increase this risk
Assessment of cognitive function is critical. Mini-Cognitive Assessment Instrument
(Mini-Cog)
Step 1 Ask the patient to repeat three unrelated words, such as “ball,” “dog,” and “television.”
Step 2 Ask the patient to draw a simple clock set to 10 min after 11 o’clock (11:10). A correct response is a drawing of a circle with all of the
numbers placed in approximately the correct positions, with the hands point to the 11 and 2.
Step 3 Ask the patient to recall the three words from Step 1. One point is given for each item that is recalled correctly.
On Mini-Cognitive Assessment Instrument
(Mini-Cog) If there is evidence of dementia
in addition to treating the patient’s pain, the provider should refer the
patient for neuropsychological testing or to a specialist who can address this important problem such as a geriatrician or neurologist.
Cognitively impaired older adults are at increased risk of pain undertreatment because of
the belief among many health-care workers that their pain ratings are unreliable. In fact, patients with mild to moderate cognitive impairment can reliably report pain using verbal descriptor scales. In patients with more advanced dementia who have difficulty using self-report instruments, caregivers rely on behavioral cues to determine the presence and severity of pain
one of the most sensitive and reliable behavioral indicators of pain in patients with dementia or poor verbal communication
Facial grimacing
other indicators of pain in patients with dementia or poor verbal communication
guarding, bracing, rubbing and sighing
Common Pain Behaviors in Cognitively Impaired
Elderly Persons
Facial expressions
- Frown; sad, frightened face, Grimace, wrinkled forehead, tightened eyes
Verbalizations/ vocalizations
- Sighing, moaning, groaning, grunting
Calling out, asking for help
Noisy breathing; verbally abusive
Body movements
Rigid, tense body posture; guarding, fidgeting
Pacing, rocking; restricted movement
Gait or mobility changes
Common Pain Behaviors in Cognitively Impaired
Elderly Persons
Changes in interpersonal interactions
Changes in activity patterns or routines
Mental status changes
Changes in interpersonal interactions
Aggressive, combative, resisting care
Decreased social interactions, withdrawn
Socially inappropriate, disruptive
Changes in activity patterns or routines
Refuses food, appetite change
Sleep, rest pattern changes
Sudden cessation of common routines
Mental status changes
Crying, tears
Increased confusion
Irritability or distress
For all patients presenting with pain ruling out serious
conditions (i.e., red flag symptoms) that require immediate attention is paramount
fever, sudden unexplained weight loss, acute onset of severe pain, neural
compression, loss of bowel or bladder function, jaw claudication, new headaches, bone pain in a patient with a history of malignancy or that awakens the patient from
sleep, and sudden pain in an extremity that is associated with pallor, pulselessness, and paresthesias
