adjuvant analgesia
a drug primarily used to treat something other than pain but also enhances pain relief
absence of sensitivity to pain
substance used as a pain deliver
analgesic ceiling
the dose of a particular drug beyond which additional amounts of the same drug do not increase analgesic effect
breakthrough pain
flaring of moderate to severe pain despite therapeutic doses of analgesics
area of skin supplied with afferent nerve fibers from a single posterior spinal root
ability of a drug to achieve its desired
epidural anesthesia
medication injected via a catheter into the space between the dura mater and lining of the spinal canal to create a regional nerve block AKA spinal anesthesia
a peripheral sensory receptor of pain
neuropathic pain
-a type of pain usually felt as burring or tingling and resulting from direct stimulation of nerve tissue of the peripheral or central nervous system
pain threshold
the point at which a person feels pain
pain tolerance
the level of pain a person is willing to endure
abn burning, prickling, tingling or numbing or hypersensitivity most often felt in the ext and typically associated with neuropathic pain
patient controlled analgesia PCA
a drug delivery system that uses computerized pump with a button the patient can press to deliver a dose of an analgesic through an IV catheter
somatic pain
generally well localized pain that results from activation of peripheral pain receptors without injury to the peripheral nerve or CNS such as musculoskeletal pain
process of gradually adjusting the dose of a medication until the desired effect is achieved
visceral pain
pain that results from activating the pain receptors of organs in the thoracic, pelvic, or abd cavities and is felt as a generalized aching, or cramping sensation sometimes referred to the surface of the body
wong baker faces scale
a pain assessment tool that asks patients ( often children) to select of the several faces indicating expressions that convey a range from no pain to the worst pain
begins with stimulation of primary sensory neurons that detect tissue damage
-damaged cells release neurotransmitters, chemicals such as bradykinin, prostglandins, serotonin, histamine and subtance p, that act to sensitize nociceptors
information is transferred from peripheral nerve fibers to the spinal cord. substance P enhances transmission at this stage. next, pain impulse is transmitted from the spinal cord to the brain stem and thalamus
-pain signal moves from thalamus to the somatic sensory cortex= pain perceived
-pain management at this level takes form of amin of opiods , which block release of substance p at spinal level
-referes to the descending control system, a regulatory mechanism by which fibers that originate in the lower middle portions of the brain and continue through to the dorsal horn of the spinal cord help prevent the continuous transmission of pain signals
-either acute (transient)
1. acute pain (transient)
-protective nature
-has an identifiable cause and is of recent onset
-results fro tissue injury
-short duration and resolves as damaged tissue heals
-intensity can be from mild to severe and can have slow or sudden onset
-triggers sympathetic nervous system and increases HR,RR and BP along with diaphoresis, pallor, dry mouth, restlessness, nausea and anxiety
-physiologic responses= reduced gastric secretion and motility, increased BS, decreased urine output and broncho dilation
2. chronic pain
-constant or intermittent but persists 6 months or more
-sometimes there is no specific cause or explanation of pain
-pain persists because the painful condition is chronic; arthritis or cancer
-more likely to be behavioral then physiologic
-ppl become discouraged, depressed and withdrawn
is pain that is specific to a particular cause
1. cancer pain
-dt tumor progression and adverse effects of various treatments
2. burn pain
-most severe type of acute pains
-burns inflammatory response makes the pain intense
1. nociceptive pain
-arises from damage to or inflammation of tissue other than that of the peripheral and CNS.
-can be somatic (musculoskeletal) or visceral (internal).
-ex: pain from surgical incision, fracture or MI
2. neuropathic pain
-dt abn or damaged nerves.
-described as burning, tingling or numbness
-responds poorly to traditional analgesics
-better controlled with adjuvant medications such as anticonvulsants, antidepressants and local anesthetics
1. idiopathic pain
-chronic pain that persists in the absence of a detectable cause
-ex= complex regional pain syndrome
2. phantom limb pain
-patient feels in the area where they previously had a limb that has been amputated
-is a form of neuropathic pain
3. referred pain
pain that originates elsewhere but is felt in another location
4. radiating pain
-pain perceived at the source and in tissues that are adjacent to the source
-ex: MI pain and radiates to the arm
5. intractable pain
-pain that defies relief
-ex= pain caused by some very advanced malignancies
after you implement the appropriate intervention for pain
-reassess the pain no later than 1 hour later
-for pharmacological intervention, reassessment should be done 30-45 min for PO med and 15-30 min for IM admin and 5-15 min for IV med
pain assessment begins with
P= provoked= what causes pain, what makes it better or worse
Q= quality= what does it feel like, sharp, stabbing, burning, crushing?
S=severity= what is the intensity of the pain
T= timing= when did it start, how often does it occur, howling does it last or is it continuous
1. determining pain intensity
numerical scale
0= no pain
1-3= mild
pictorial scale
-for patients who cannot understand or respond to a numeric or visual analog scale
-effective for young children, adults with cognitive difficulties and patients who do not speak same language
-ex= wong baker faces = 6 cartoon like drawings ranging from smiling face to crying face
-ex= another scale is ouched pain scale
when a patient cannot communicate
-see if the patient has a diagnosis or problem that usually causes pain (objective data)
-look for behavior that might indicate pain
-ask family member or other if they believe that the patient has pain
-check for physiologic responses that might indicate pain such as elevated pulse and respiratory rates
effects of unrelieved pain
-stresses many body systems
-endocrine and cardiovascular system respond with increased activity and the bodes metabolism speeds up
-resp, genitourinary and GI reduce there function
-muscle spasms, fatgiue and altered function occur
-immune sys becomes depresses
-unrelieved acute pain can lead to chronic pain