Basics of Pain Assessment

Pathophysiology Nociceptive pain Neuropathic pain Idiopathic pain Psychogenic pain Commensurate with identifiable tissue damage May be abnormal, unfamiliar pain, probably caused by dysfunction in PNS or CNS Pain, not attributable to identifiable organic or psychologic processes Sustained by psychologic factors

Nociceptive Pain Presumably related to ongoing activation of primary afferent neurons in response to noxious stimuli Pain is consistent with the degree of tissue injury Subtypes – Somatic: well localized, described as sharp, aching, throbbing – Visceral: more diffuse, described as gnawing or cramping

Neuropathic Pain Pain believed to be sustained by aberrant somatosensory processing in the peripheral or central nervous system

Idiopathic Pain Pain in the absence of an identifiable physical or psychologic cause Pain is perceived to be excessive for the extent of organic pathology

Psychogenic Pain Pain sustained by psychological factors More precisely characterized in psychiatric terminology Patients have affective and behavioral disturbances Patients with organic component often have concurrent psychologic contributions and comorbidities “Chronic pain syndrome” sometimes used to depict this phenomenon

Pain Syndromes Acute pain Chronic pain Breakthrough pain Recent onset, transient, identifiable cause Persistent or recurrent pain, beyond usual course of acute illness or injury Transient pain, severe or excruciating, over baseline of moderate pain

Types of Pain Acute Pain – Pre/post surgery – Traumatic injury – Medical treatment (chemotherapy, OT/PT) – Disease process – Labor & delivery Chronic Pain – Injury – Disease process

Transition from Acute to Chronic Conceptual Model Three Stages (Gatchel 1991, 1996) Stage 1 associated with initial psychological distress due to acute pain. Stage 2 (pain persist 2-4 months) associated with wide array of behavioral and psychological reactions – learned helplessness, somatization, depression …

Transition from Acute to Chronic Conceptual Model Stage 3 associated with acceptance of the sick role and is excused from social obligations – Deconditioning syndrome

Pattern: onset & duration Area: location Intensity: level Nature descripti on PAIN Pain Assessment: Goals

Characterize the pain Identify pain syndrome Infer pathophysiology Evaluate physical and psychosocial comorbidities