Pain
Contraindications for DIRECT acting skeletal muscle relaxants
- Hepatic disease - Lactation
What does phantom pain not usually respond to?
Common pain therapies
Codeine can also be used for what?
Cough suppression
Diphenoxylate can also be used for what?
Decrease peristalsis for an antidiarrheal (decreases frequency of stools)
What may or may not be present?
Aura may or may not be present Jagged lines, flashing lights, special smells/tastes/sounds
Drug to drug interactions with muscle relaxants
CNS depressants
What is the most common side effect with opioids?
Constipation
Who has hard time with pain scale?
Dementia and kids
What goes hand in hand with chronic pain?
Depression - almost all on antidepressants
How do patients describe neuropathic pain?
Described as burning, shooting or numb pain
Management of neuropathic pain?
Difficult to manage
Adverse reactions to muscle relaxants
Drowsiness Fatigue Weakness Confusion Headache Nausea dry mouth hypotension
What do you do if headaches or migraines continue?
Drug therapy
Inhibitory endogenous NT
Endorphines - feel good hormone that will prevent production from going on in pain pathway
Botulinum toxins and dantrolene
Enter muscle fibers directly botox- used for migraine
drug to drug interactions with DIRECT acting skeletal muscle relaxants
Estrogen Neuromuscular junction blockers
Adverse reactions with DIRECT acting skeletal muscle relaxants
Fatigue Weakness Confusion GI irritation Enuresis
What do sublingual and buccal exempts drug from?
First pass effect
What happens when gates are open vs. closed
Gates open - Pain impulses transmitted from periphery to brain Gates closed - Reduces or modifies the passage of pain impulses
Location of chronic pain
Generalized usually
Timing of chronic pain
Occurs over extended time; may be recurrent
What is there a risk for with narcan?
Risk of hepatotoxicity (effects liver) - doesn't matter if liver is effective if not breathing
Who is Prophylactic Therapy used for?
Used for people where abortive therapy is not effective or d/t frequency
What does chronic pain reduce tolerance to?
Usually reduces tolerance to additional pain
How can you standardize patient's conveyance of pain and measure progress during drug therapy?
Utilize surveys and scales
Triptan (sumatriptan) causes what effect
Vasoconstricts intracranial arteries
Side effects of tramadol (ultram)
Vertigo, dizzy, h/a N/V constipation, lethargy
What might occur with acute pain
Vomitting - very strong emotional response
When will phantom pain resolve?
WIthin weeks-months
What should you watch for with triptan?
Watch for cardiac ischemia * first dose in MDO
What should you watch for with combination drugs?
Watch for hepatic toxicity with acetaminophen
How is the pain signal transmitted with nociceptive pain?
Way that pain signal is transmitted to brain is because of nociceptive nerve fibers (kinin and prostaglands - chemical stimulation) or mechanical stimulation (nail) or thermal (heat) KNOW!!
Acute pain initiates what physiologic stress responses?
↑ blood pressure and heart rate; cool, pale, moist skin; ↑ respiratory rate; ↑ skeletal muscle tension
Referred pain
- Source may be difficult to determine. - Pain may be perceived at site distant from source.
TENS Treatment
When signals are going and synapsing to first synapse, if you bring stimulation in from other nerve fibers that can jump in in front of noceceptive receptor coming through and block it. Additional nerve receptors
Cautions with DIRECT acting skeletal muscle relaxants
Women All patients older than 35 years Cardiac disease
How does tramadol (ultram) work?
Works by inhibiting reuptake of norepinephrine and serotonin in spinal neurons
Why does nociceptive pain respond to conventional pain relief?
because with NSAID we are blocking prostaglanin production meaning nociceptive nerve wont be stimulated by prostaglandin anymore. Chinin might still cause some pain which is why we often combine NSAIDS with narcotics.
Opioid antagonists
block opioid receptors (block mu and kappa)
Pure opioid antagonist
block receptors so not stimulated - will feel pain
What is a migraine headache characterized by?
by throbbing or pulsating pain
Administeration routes of triptan?
Available in oral, intranasal and subuctaneous
Pure opioid agonists will stimulate wat?
Both mu and kappa
Neuromuscular Abnormalities
- muscle spasms - muscle spasticity
Abortive therapy
Attempt to stop a migraine that has started
Neuropathic pain is caused by what?
Neuropathic pain is caused by injury to the nerves
What happens during tension headaches
- Muscles of head/neck become tight d/t stress - Results in steady/lingering pain
Treatment of chronic pain
Usually more difficult to treat than acute pain
Non-Opioid Analgesics
- NSAIDS- non-steroidal anti-inflammatories - acetaminophen - centrally acting drugs
Avoid triptan in what patients?
**Avoid in pts. with recent MI, h/o angina, HTN, Diabetes
Several drugs are obtained from opium
- Natural substances -Morphine/Codeine - Synthetic substances- Meperidine (both called opiates/opioids)
Cluster headache
Pain is in and around one eye
Who does phantom pain usually occur with?
adults
Thalamus and limbic system
Emotional factors
Migraines are usually accompanied by what?
N/V
Nociceptic pain is characterized by what 2 things?
1. "somatic" pain 2. "visceral" pain
What is pain considered?
- A universal experience - A defense mechanism
Pain fibers
- Afferent fibers - Myelinated A delta fibers - Unmyelinated C fibers
Patient-controlled analgesia (PCA)
- Alternative pain medication delivery system - Patients self-medicate with opiate medication by pressing a button - Medication delivered intravenously via infusion pump
What are both kappa and mu responses?
- Analgesia - Decreased GI mobility - Sedation
Kappa receptor responses
- Analgesia - Decreased GI mobility (const.) - Miosis (pupils constrict) - Sedation
Psychological influence- what increases pain perception?
- Anxiety - Fatigue - Depression
Dermatome
- Area of skin innervated by a specific spinal nerve - Somatosensory cortex → "mapped" - Corresponds to source of pain stimuli Dermatomes - how we know how neurons are mapped (if have nerve pain in 2 fingers, we know which spinal nerve is affected)
Role of nurse with opioid therapy
- Assess potential for opioid dependency Have narcotic antagonists available to reverse negative effects - Assist with activity - Monitor urine output for retention - Monitor patient's bowel habits for constipation
Administration
- Breakthrough pain - Titration
Examples of referred pain
- Characteristic of visceral damage in the abdominal organs - Heart attack or ischemia in the heart
What can stimulate pain?
- Chemical receptors: prostaglandins and kinins which are released during inflammatory response - Mechanical - Thermal
Combination Drugs
- Combine opioids and non-narcotic analgesics into a single tablet/capsule - Work synergistically, can keep dose of opioid small reduces dependence and narcotic-related side effects
Role of the Nurse: Opioid Antagonist Therapy
- Continue careful monitoring of patient's condition Especially respiratory status - Have resuscitative equipment available
Theory of pain: Gate Control Theory
- Control systems, "gates" built into normal pain pathway - Can modify pain stimuli conduction and transmission in the spinal cord and brain
Neonatal pain scale
- Dependent on your observation of how that baby is behaving then score the number and add them up to figure out if baby is comfortable or not
Titration
- Dose adjustment based on assessment of analgesic effect versus side effects - Use the smallest dose to provide effective pain control with fewest side effects.
caution with skeletal muscle relaxants
- Epilepsy - Cardiac dysfunction - Conditions marked by muscle weakness
Action of skeletal muscle relaxants
- Exact mechanism of action is not known - Thought to involve action in the upper or spinal interneurons
Fentanyl/Duragesic
- Fentanyl transdermal system - Also nasal spray, and lozenge - Controls moderate to severe chronic pain - Provides longer lasting relief from persistent pain
Opioid agonists
- First line choice for moderate to severe pain - More than 20 different options, classified by effectiveness - Strong or Moderate
"Visceral" pain
- Generalized dull, throbbing, aching sensations - Organs - Conducted by sympathetic fibers - acute or chronic Ex. liver inflammation from hep, viral nephlitis (just organs)
Pain control
- Ice - TENS - Opiate-like chemicals (opioids)
Physiologic reactions to chronic pain
- Individual may be fatigued, irritable, depressed - Sleep disturbances common - Appetite may be affected. Leading to weight gain or loss
DIRECT acting skeletal muscle relaxants actions
- Interfering with the release of calcium from the muscle tubules - This prevents the fibers from contracting - Does not interfere with neuromuscular transmission
Reflex Response
- Involuntary muscle contraction away from pain source - Involuntary muscle contraction to guard against movement
Pain threshold
- Level of stimulation required to elicit a pain response - Usually does not vary between individuals
Signs, Symptoms and Diagnosis of pain
- Location of pain - Description terms - Timing of pain - Physical evidence of pain
Spinothalamic bundle in the spinal cord
- Neospinothalamic tract - Paleospinothalamic tract Spinothalamic tracts connect with reticular formation of brain
Pain scale assessment
- Numeric scales 0-10 - Face scales - Pain thermometer - Neonatal pain scale
Muscle spasm
- Often results from injury to the musculoskeletal system - Caused by the flood of sensory impulses coming to the spinal cord from the injured area
Pain assessment characteristics
- Onset - Location - Duration - Characteristics - Aggravating factors - Relieving factors - Treatment (OLDCART)
Because pain begins at the nociceptors in peripheral tissues and proceed throughout the CNS, allows several targets for pharmacologic intervention
- Opioids- act within the CNS - Non-steroidal anti-inflammatories- act at the peripheral tissue level (near noceceptors)
Administration routes for opioids
- Oral - Sublingual and buccal - Intranasal - Rectal - Transdermal - Parental - Intraspinal - Implantable pumps - Patient-controlled analgesia (PCA)
Process of pain
- Pain transmission begins when pain receptors (nociceptors) are stimulated (by prostaglands, kinins, or mechanical or thermal) - Nerve impulse signaling pain is sent to spinal cord via sensory neurons (aka: pain fibers) - Pain impulse reaches spinal cord and needs to travel to the next set of neurons- NEUROTRANSMITTERS are responsible for assisting (substance P) - If pain signal reaches the brain, the person responds
Physical evidence of pain
- Pallor and sweating - High blood pressure or tachycardia
Chronic pain
- Persists over a longer time - 6 months is the standard - Interferes continuously with daily activities
Psychological influence - what decreases pain perception?
- Positive attitudes - Support from caregivers - Awareness of cause - Awareness of treatment options
Opioid Dependence
- Potential to cause physical and psychologic dependence - Patient-controlled analgesia (PCA) - Combinations with nonnarcotic analgesics
Pharmacokinetics of muscle relaxants
- Rapidly absorbed and metabolized in the liver - Excreted in the urine
Adverse effects of opioid agonists
- Respiratory depression - Sedation - N/V - Physical & psychological dependence - Pruritis (histamine release)
Muscle spasticity
- Result of damage to neurons within the CNS - May result from an increase in excitatory influences or a decrease in inhibitory influences within the CNS
Reticular activating system (RAS)
- Reticular formation in the pons and medulla - Awareness of incoming brain stimuli
What does narcan do?
- Reverses respiratory depression and other acute symptoms - Can result in BP increase, RR increase, N/V/drowsy/tremors
Opiate-like chemicals (opioids)
- Secreted by interneurons of the CNS (endogeneous) - Block conduction of pain impulses to the CNS - Resemble morphine Enkephalins, dynorphins, beta-lipoproteins
Somatic pain
- Sharp, localized sensations - Bone, muscle, skin - Conducted by sensory fibers Ex. shingles
Other uses for opioid agonists besides pain
- Slow the GI tract motility - Suppress the cough reflex - CNS depressant effects
Pharmacokinetics of DIRECT acting skeletal muscle relaxants
- Slowly absorbed from the GI tract - Metabolized in the liver - T ½ 4-8 hours - Excreted in the urine
Opioids with Mixed Agonist-Antagonist Activity
- Stimulate opioid receptor, thus causing analgesia - Withdrawal symptoms and side effects not as intense as those of opioid agonists
Treatment for Opioid Dependence
- Switch from IV and inhalation forms to methadone, the oral form - Methadone maintenance * Does not cure but avoids withdrawal symptoms * Treatment may continue for many months and years.
Benefits of variable routes of opioids
- Target a particular source - Achieve therapeutic blood levels rapidly - Avoid certain side effects - Provide analgesia when patients cannot swallow
Most common headahces
- Tension headache - Migraine headache
Pain tolerance
- The ability to cope with pain - Culturally related - Varies between individuals (subjective)
Somatic sensory area in cerebral cortex is located where and is responsible for what?
- The somatic sensory area in the cerebral cortex located in the parietal lobe - Perception and localization of sensation
Breakthrough pain
- Transient, moderate to severe - Occurs beyond treated pain - Usually rapid onset and brief duration with variable frequency and intensity
Unmyelinated C fibers
- Transmit impulses slowly - Chronic pain - Diffuse, dull, burning, or aching sensation
Myelinated A delta fibers
- Transmit impulses very rapidly - Acute pain - Sudden, sharp, localized
Indications for DIRECT acting skeletal muscle relaxants
- Treatment of spasticity directly affecting peripheral muscle contraction - Management of spasticity associated with neuromuscular diseases
Examples of combo dugs?
- Vicodin: hydrocodone; acetaminophen 500mg - Percocet: oxycodone; acetaminophen 325mg - Percodan: oxycodone; aspirin 325mg
Muscle relaxants
- Work in the brain and spinal cord - Interfere with cycle of muscle spasm and pain
Action of Centrally Acting Skeletal Muscle Relaxants
- Work in the upper levels of the CNS to interfere with the reflexes causing the muscle spasm Possible depression anticipated with their use - Lyse or Destroy Spasm Often referred to as spasmolytics
Classification of pain
- acute - chronic - nociceptive pain - neuropathic pain
Mu receptor responses:
- analgesia - decreased GI activity - Euphoria - Physical dependence - Respiratory depression - Sedative
Which are the two most important receptors for pain management?
1. Mu 2. Kappa
How often do you change fentanyl transdermal patch
72 hours
Descriptive terms of pain
Aching, burning, sharp, throbbing, widespread, cramping, constant, periodic, unbearable, moderate
Non-pharmacologic Techniques for pain management
Acupuncture Imagery Biofeedback therapy Chiropractic manipulation Massage Hypnosis Heat/cold Therapeutic touch Meditation/Prayer TENS Relaxation therapy Reiki/Qi gong Art therapy
How is narcan administered?
Administered IV- repeat Q 2-3mins
Indications of skeletal muscle relaxants
Alleviation of signs and symptoms of spasticity; use in spinal cord injuries or diseases
When does phantom pain often occur following?
Amputation - pain, itching, tingling
Acute pain
An intense pain occurring over a brief period of time
Examples of prophylactic therapy drugs?
Anti-seizure drugs Beta-adrenergic blockers- Inderal Calcium channel blockers Antidepressants- Elavil Neuromuscular blockers Botox
Timing of pain
Association with an activity
Headaches
Headaches are one of the most common complaints of patients
Intraspinal delivery
Highly potent (smaller doses necessary)
WHen is phantom pain more common
If chronic pain has occured
Non-pharm techniques for pain magaments May be used alone or in conjunction with pharmacotherapy, if so can result in what?
If used concurrently, can result in lower doses and fewer drug-related adverse effects
Ice
Impulses from temperature receptors close gates
TENS
Increases sensory stimulation at site, blocking pain transmission
Sources of pain
Inflammation Infection Ischemia and tissue necrosis Stretching of tissue Stretching of tendons, ligaments, joint capsule Chemicals Burns Muscle spasm
What do non-opioid analgesics do? NSAIDS
Inhibit cyclooxygenase, therefore inhibit prostaglandins ASA, IBU, Cox-2
Who do you use wong-baker faces pain scale with?
Kids, elderly, language barriers
Contraindications in skeletal muscle relaxants
Known allergy Rheumatic disorders - kidney failure
Contraindications of DIRECT acting skeletal muscle relaxants
Known allergy Spasticity
What triggers a migraine?
MSG, red wine, perfume, caffeine, chocolate, aspartame, food additives
Max dose of triptan?
Max dose is 2x/day (60 min apart)
Location of acute pain
May be localized or generalized
What is a drug we give for heroin or narcotic abusing people?
Methodone which effects kappa receptors but not mu so helps by giving them what they need as far as dependence drive but safer - still works for analgesia so will feel good
What is the most painful type of headache?
Migraine
Types of abortive therapy
NSAIDS or Acetaminophen- first line Non-opioid prescription medsAsacomp/Fioriciet- Triptans- Serotonin 5Ht agonists Ergot Alkaloids
Example of opioid antagonist
Nalaxone- Narcan
What do you give for overdose on heroin or morphine?
Narcan
Nociceptive Pain is caused by what?
Nociceptive pain is caused by damage to tissues
How do opioids work?
Opioids exert their actions by interacting with 6 types of receptors
What is the route of chocie when have a functioning GI tract?
Oral
Headaches lead to what
Pain and inability to focus and concentrate= Work related absences, difficulty caring for home and family
What is pain?
Pain is an experience characterized by unpleasant feelings
Sinus headache
Pain is behind the forehead and/or cheekbones
Migraine headache
Pain, nausea, and visual changes are typical of classic form
Patients with chronic pain might have periods of what?
Periods of acute pain may accompany chronic pain conditions.
Phantom Pain
Phantom pain happens because when one thing gets stimulated its because of finger down here - with amputations think hand is still there bc nerves still stimulating that same spot in brain
What does nociceptive pain respond to for treatment?
Responsive to conventional pain relief medications
Cause of chronic pain
Specific cause may be less apparent.
process of pain
Stab finger- prostglandins and kinins released -stimuales noceceptical fiber and gets into dorsal route of spinal cord, once it gets there is synpases onto 2nd neuron which is myelinated brings it up into brain into thalamus. In thalamus it synapses to 3rd neuron which then goes to diff areas of brain so can feel it and bring into conscious thought and know it happened
pain pathway review
Stimulus (nail through them) Noceceptor is stimulated Peripheral nerve - afferent pain fiber (going towards) Coming into dorsal horn where first synapse is! 2nd order neuron is myelinated so will be fast track to brain Subsatnce P -can block this with TENS unit or massage Nerve transmission crosses over and comes up spinal thalamic track and into brain Distrubted to 3rd order neuron Into limbic system, thalamus is where we recognize it Where it is in the brain is where we get conscious thought
The psychological reaction to pain is what?
Subjective - varies from person to person
Opioid Antagonist
Substances that prevent the effects of opioid agonists Block opioid activity
When do you take triptan
Take as soon as migraine h/a is beginning
What is the most common type of headache?
Tension headache
How fast does triptan work?
Terminates migraine h/a in 10-20 minutes
Centrally acting drug
Tramadol (Ultram)- weak opioid activity
What is pain usually associated with?
Trauma or disease
What do you treat tension headaches with
Treat w/OTC analgesics- asa/ibu/acetaminopthen
Treatment of migraines
Treatment- tx before reaches severe level Abortive therapy Preventative therapy
5-HT receptor drug
Triptan (sumatriptan)
What therapy can you also use?
Use combination non-opioid pain alternatives if needed - Fioricet- acetaminophen, butalbital - Ascomp- asa, caffeine, butalbital
Who gets neuropathic pain
diabetics and shingles
Narcotic
general term used to describe opioid drugs that produce analgesia and CNS depression
Tension headache
pain is like a band squeezing the head
What is an example of Opioids with Mixed Agonist-Antagonist Activity
pentazocine (Talwin)
Prophylactic Therapy
prevent migraine headaches
Massage, heat/cold therapy
providing another sensation that needs to go up that nerve to the brain blocking the noceceptive receptors
Opioid agonists
stimulate opioid receptors (mu and kappa)
Signs travel from what 3 places
thalamus - somatic sensory area - limbic system
What does acute pain indicate?
tissue damage
Timing of acute pain
very sudden and severe, short term
Mixed opioid agonist
will stimulate only mu or only kappa (kappa is better)