Nancy Wiedemer,CRNP

Pain Management Coordinator

Philadelphia VA Medical Center nancy.wiedemer@med.va.gov

Not all pain is the same: implications Not all pain is the same: implications for assessment and treatment for assessment and treatment

Assessment and Treatment of Pain:Issues and Challenges

Underassessment and undertreatment

Interpatient variability Patient not believed OPIOIDS Complex pathophysiology

Defining Pain

Arthritis

Spinal Stenosis

Failed Back

Neuropathy DM,PHN,HIV,post CVA Cancer

Pain Mechanisms

Acute

Chronic < episodic < persistent

End of life

Defining Pain

By definition…… a disease process alters the way a system or organ system responds to different types of homeostatic processes within the body.

Hypertension

DiabetesChronic Pain

Chronic Disease

Biopsychosocial Model of Pain

Suffering

People suffer from what they have lost of themselves…..

it continues until the threat of disintegration has passed or until the integrity of the person can be restored in some other manner.

Eric J Cassel, NEJM , 1982

Cascade of negative emotions experienced by health care providers

Inadequacy

Helplessness Frustration Anger

Gallagher,2004

PAIN is a sensory processing system with a known anatomy and physiology

WHAT IS PAIN?

Overview of Pain Perception

Physiology of Pain Perception

• Transduction

• Transmission

• Modulation

• Perception

• Interpretation

• Behavior

Injury

Descending Pathway

PeripheralNerve

Dorsal RootGanglion

C-Fiber

A-beta Fiber

A-delta Fiber

AscendingPathways

Dorsal Horn

Brain

Spinal CordAdapted with permission from WebMD Scientific American® Medicine.

Transient pain in response to a noxious stimuli Key early warning – Alarm system Announces the presence of a potentially

damaging stimulus

Nociceptive Pain

Woolf,CJ Ann Internal Med 2004;140:441-451

Tissue damage edema activation of mechanoreceptorsRelease of chemicals from mast cells and injured nociceptors

Woolf,CJ Ann Internal Med 2004;140:441-451

Glutamate

HistamineProstaglandinSubstance PSerotoninBradykinin

Nociceptive Pain

SOMATIC Well-localized Aching,throbbing, gnawing

bone joints soft tissue muscle skin

VISCERAL Poorly localized Deep aching,

cramping,pressure, Referred

Bowel obstruction Biliary colic liver pain appendix

NEUROPATHIC PAIN

Afferent fibers

C fiber

A beta fiber

Nerve injury

PhenotypicalChanges

Spinal cord

Neuro-plasticity

Central sensitization

Alteration of modulatory

systems

Ectopic discharge

Ectopic discharge

Woolf & Mannion, Lancet 1999Attal & Bouhassira, Acta Neurol Scand 1999

Central Sensitization

Overview of Pain Perception

Physiology of Pain Perception

• Transduction

• Transmission

• Modulation

• Perception

• Interpretation

• Behavior

Injury

Descending Pathway

PeripheralNerve

Dorsal RootGanglion

C-Fiber

A-beta Fiber

A-delta Fiber

AscendingPathways

Dorsal Horn

Brain

Spinal CordAdapted with permission from WebMD Scientific American® Medicine.

Modulation of Pain Perception

Antinociceptive system

Endorphins Enkephalins Receptor sites

GABA

OpioidsSerotoninNeurepinephrine

Endorphins Enkephalins

Opioids

Neuropathic Pain: injury to peripheral nerves and/or CNS

Burning Stinging Shooting Lancinating Pins and needles Vicelike Electric Tingling

Focus of medical attention is often centered

on nerve/disc/bony relationship

Little to no attention is given to the soft tissue that supports and binds the spine

The Myofascial System

• Guarded movements• Pelvic tilt when standing• Limited flexion and extension in the spine• Paraspinal tenderness•Trigger points – active or latent

Myofascial Pain

Deep aching pain Burning or stinging sensation Restricted movement in involved areas Muscle spasms Trigger points- feel indurated to

palpation Taut muscle bands

VAClinician

Pain Assessment

What is the pain generator ?

What is the pain mechanism ? Nociceptive Neuropathic Myofascial Mixed

Are there pain amplifiers ?

Anxiety Depression PTSD Substance Abuse Disorder

Pain Assessment

Tumors Fractures Infection Cauda Equina

Syndrome

Factors that may impede recovery:

Emotional state Fear-avoidance

beliefs Poor coping

strategiesLinton,SL & Boresma,K,2003

Are there RED FLAGS ?????

History and Physical Exam Events at pain onset Pain:

site & radiation quality intensity (numeric score 0-10) temporal pattern provocations & sources of relief

Activities and functional limitations Sleep disruption Previous therapies

Conclusions

Chronic Pain ↔ Chronic Disease

Chronic Disease Management Approach

based on

Biopsychosocial Model

Conclusions

Not all patients with the same pain diagnosis have the same pain mechanisms

Different mechanisms can coexist Treatment approaches that target

each pain generator can improve outcomes

Conclusions

Secondary prevention depends onearly and aggressive assessment

and management of pain