Pain Management Elizabeth Whiteman, M.D.

Goals and Objectives Pathophysiology of pain Classification of pain Assessment of pain Treatment ▫Analgesics ▫Non Pharmacological ▫Specialty

Four Components of Pain Physical pain ▫Can be multifactorial Emotional pain ▫Anxiety, depression, fear Social or interpersonal pain ▫Not working, family, friends Spiritual or existential

Consequences of pain Depression Decreased socialization Impaired ambulation Sleep disturbance Malnutrition Polypharmacy Suffering

Other chronic causes of pain, in addition to current illness Osteoarthritis Constipation Pressure ulcers Headaches (migraine etc) Muscle strain, deconditioned Post surgical

Classification of pain

Nociceptive Pain ▫stimulation of pain receptors ▫visceral or somatic ▫tissue injury, inflammation, mechanical ▫Described as “tender” or “deep and aching” ▫Responds to opioids and also adjuvant pain medication if needed

Neuropathic pain ▫peripheral or central nervous system ▫often respond to non conventional analgesics ▫Described as “burning” or “shooting” ▫Light touch may be severe pain sensation (allodynia) ▫Usually adjuvant drugs more helpful

Pain Assessment

Assessment Most reliable indicator is patient’s report Reliable pain scales Cognitively impaired persons Use of proxies Non verbal assessment Full history and physical exam

Reasons patients may not report pain Fear of pain Fear of testing Fear of medications Believe nothing can be done Worry physician is too busy Worry complaining may effect care Don’t want to be a burden

Assessment Pain history and medical history Physical exam ▫Good neurologic and orthopedic exam Functional status ▫ADL’s (activities of daily living), Gait, activities, use of assist device Psychological assessment Cognitive function

Pain Scales

Pain Management

Management Analgesic ladder ▫treat according to intensity of pain Routes of administration Around the clock Breakthrough pain Short vs. long acting

WHO Analgesic Ladder Pain Opioid Mild to moderate pain + Non Opioid +/- Adjuvant Opioid Moderate-Severe Pain +/- Non Opioid +/- Adjuvant Non Opioid +/- Adjuvant

Dosing Around the clock ▫Need routine dosing ▫Long acting preparations Breakthrough pain ▫Short acting preparations ▫Monitor needs and episodic pain

Pharmacologic Treatments

Analgesics Acetaminophen Non steroidal Anti-inflammatory  Non Specific COX inhibitors (COX 1 and 2)  COX 2 inhibitors Opioids ▫useful in moderate and severe pain ▫tolerance to cognitive side effects, respiratory depression and nausea ▫Constipation should be prevented

NSAID’s ▫Beneficial in inflammation ▫Used alone or in combination Nonspecific (Ibuprofen, Naproxen) ▫GI ulcers, gastritis, GERD ▫Renal effects Cox 2 inhibitors (Celecoxib, Meloxicam) ▫Less GI side effect, still use with caution) ▫Renal effects the same ▫Cardiac risk factors

NSAID’s Patient’s should be taking with food If GI upset or pain, reassess GI Prophylaxis ▫Carafate, H2 Blockers, proton pump inhibitor Caution in use with patient with platelet disorders

Opioids

Long acting and short acting Long acting drugs ▫Morphine sulfate, Oxycodone ▫Should be used routinely ▫Monitor for side effects Short acting ▫Breakthrough pain ▫Episodic pain

Starting Opioids Opioids naive patient start slow Oral first line if patient can swallow Short acting prn, or around the clock if constant pain Can then calculate long acting needs IV or Subcutaneous infusion if need rapid titration or unable to take other route

Special populations Frail elderly Liver patients Dementia Renal failure Drug users

Adjuvant medications

▫Antidepressants ▫Anti seizure medication ▫Anticholinergics ▫Local anesthetics ▫Corticosteroids ▫Other: calcitonin, bisphosphonates ▫Muscle relaxants ▫NMDA inhibitors

Antidepressants Tricyclic Antidepressants ▫For neuropathic pain ▫High side effects- Anticholinergic ▫Use with caution in elderly SSRI’s, SNRI’s ▫Can be used as adjuvant medication ▫Duloxetine is approved for diabetic neuropathy (off label for post herpetic neuralgia)

Anti seizure medications ▫Carbamazepine, phenytoin  Monitor LFT  Risk for sedation ▫Pregabalin (lyrica)  Approved for diabetic neuropathy and post herpetic neuralgia  mg tid dosing  Need to renal dose

Gabapentin Good results for neuropathic pain ▫Sharp shooting pain, numbness, burning Usual effective dose mg/day in 3 divided doses Slow and gradual dose increase ▫100mg QD to start, increase by 100mg every 3-5 days as tolerated ▫100mg bid-100mg tid etc…

Topical anesthetics Ice, heat,massage Heated rubs (BenGay, icy hot etc.) topical NSAID creams Lidocaine Patch Capsaicin cream

Bone Pain NSAID’s ▫Alone or in combination with Opioids Corticosteroids ▫Metastatic bone pain Calcitonin (studies vary on effectiveness) ▫Osteoporosis and fractures Bisphosphonates ▫Paget’s Disease Radiation therapy ▫Bone metastasis

Non Pharmacologic

Non drug Strategies Patient education Relaxation techniques, cognitive therapy Physical exercise, therapy Ice, heat, massage Biofeedback (TENS unit) Acupuncture, acupressure

Other types of pain Physical Emotional Social Spiritual Use team: from the start !!! Social workers, chaplain, home health aide, physical therapy, family/ friends included

Other treatments Refer to pain specialist ▫Epidural ▫Nerve block ▫Nerve stimulator Surgery ▫Minimally invasive surgery ▫Joint replacement or spine Radiation therapy Palliative Chemotherapy ▫If possible help shrink tumor size, relieve pain

Summary Patients may have atypical presentation Need to fully assess pain and be able to monitor symptoms Assess type of pain Pain medication treatment Avoid side effects Non pharmacologic treatment Remember specialists if appropriate Involve other team input

References Hanks,G, Cherney,N et al, eds., Oxford Textbook of Palliative Medicine, pages , Oxford University Press, New York, Jacox,A, Carr,D, Payne,R, New Clinical Practice guidelines for the Management of Pain in Patients with Cancer, New England Journal of Medicine, Vol 330, No 9, Whitecar,P, Jonas,P Clasen,M, Managing Pain in the dying patient, American Family Physician, Feb 1;61(3): , 2011.