Abdurrahman Omar As-sarisi Pain Management Abdurrahman Omar As-sarisi

Lecture outlines Definition of pain Pain score Types of pain Pathophysiology of pain

Definition of pain According to the International Association for the Study of Pain (IASP): It’s an unpleasant sensory and emotional experience associated with actual or potential tissue damage. It’s a defense mechanism that warns you about injuries so that you take a protective action.

Pain score

Cont. 0 = The patient has no pain. 2 = (Mild) Nagging, annoying but doesn’t interfere with most daily living activities - Example: like lightly pinching the fold of skin between the thumb and first finger with the other hand, using the fingernails 4 = (Moderate) Frustrating, patients notice the pain all the time and cannot completely adapt. Patient can still do most of the daily activities with rest. (e.g. The initial pain from a bee sting, or minor trauma)

Cont. 6 = (Moderate) Intense pain, interferes with some daily activities. 8 = (Severe) Horrible pain, patient can hardly think of anything else because of the pain. (e.g.: Acute pancreatitis) 10 = (Severe) Disabling pain, patient unable to function independently. (e.g. Pelvic fractures)

Types of pain Acute pain : the normal body responds to a noxious stimuli with the experience of pain. By other words It’s the pain that lasts only until the noxious stimulus is removed or the damage is healed. Chronic pain : the sensitized nervous system more readily to both noxious and innocuous stimuli Simply ,It’s the pain that extends beyond the expected time (no exact limits)

Some subdivisions of chronic pain Pain from continuing tissue damage : Rheumatoid arthritis (pain restricts movement and prevents further joint damage). Chronic benign pain : pain despite of tissue healing. Sudeck’s atrophy ,associated with allodynia and hyperalgesia. Cancer pain : actually It’s a combination of several acute pains from destructive effects of the tumor

Pathophysiology of pain

Tissue injury Nociceptors  Nociceceptive fibers  Dorsal horn  Spinothalamic tract (localization) & Spinoreticular tract (emotional aspect)  thalamus  Somatosensory cortex. Nociceceptive fibers  Aβ fibers : fast - myelinated C fibers : slow - unmyelinated

Cont. Simple stimulation : for example sensation of pressure (mechnoceptors). Prostaglandins : sensitize nerve endings to react more intensely to further stimulation. Other stimuli : impulses of pain and temperature are carried on the same small fibers, and the threshold is reduced at low temperature, arthritis pain worsens in cold weather. Peripheral nerve injury : due to regeneration (neuroma) to the injury Itself. Denervation : when receptors are absent as in amputation, phantom limb pain. Central pain : spinal cord tracts Higher pain : in the brain (emotional)

Thank you