Exam 3 - Lecture 21 Pain Management Flashcards
Which organization incorporated pain management standards into accreditation requirements in 2000?
JCAHO
What are the two components of pain?
- Physiological Sensation
- Emotional psychological reaction to that sensation (most important, represents “suffering”)
Approaches to Managing Pain
- Remove cause
- Decrease Inflammation, irritation, and sensitivity of nerve endings (aspirin, NSAIDS, and related agents)
- Block conduction of impulses by pain fibers (local anesthetic, ex. Lidocaine)
- Modify Processing of pain information in the CNS (opioids, aspirin, acetaminophen, NSAIDS and related agents.
Aspirin, ibuprofen, NSAIDS, and related agents
- Inhibitors of Prostaglandin synthesis (COX-1 and COX-2)
- Acts on nerve endings and in the CNS to alleviate pain
- Anti-inflammatory effects
- Adverse Effects: GI (irritation, bleeding, etc.), potential serious CV side effects (hypertension, MI, stroke, etc.)
What does COX-1 and COX-2 produce from the Arachidonic acid precursor?
Prostaglandins and other similar compounds.
What happens when the COX-1 and COX-2 pathways with arachidonic acid are inhibited?
Lipooxygenase Pathway which produces Leukotrienes (involved in the pathology of asthma attacks)
Acetaminophen
-Inhibits prostaglandin synthesis in nerve endings and CNS, not in periphery.
-Acts on nerve endings and in CNS (unknown mechanism of action)
- No Anti-inflammatory response
- No GI irritation
- Adverse Effects: Potential Hepatotoxicity at high doses
Ketorolac (Toradol)
- Injectable NSAID
- Alternative to opioids for pain
- Adverse Effects: GI irritation
- Short term (<1-2 days) use but not for chronic use.
Celocoxib
Selective COX-2 Inhibitor
Local Anesthetics
- Block Na channels in nerve endings and axons. Stoping generation and conduction of APs.
- small, unmylenated pain fibers are the most sensitive
- Powerful pain relief with spinal, regional, and nerve block techniques.
- Invasive (may effect motor function and sensory modalities)
- Low doses are used (selective pain relief, less affect on other functions)
- Used for surgical pain and chronic pain syndromes
Prototype of Local Anesthetics
Lidocaine
Dependence and Addiction
-Drug dependence does not mean addiction.
- Most studies have shown that most patients who take opioids for medical purposes do not become “addicts”
- prescribes must be careful to prevent abuse.
Drug dependence
- physiological state resulting from chronic exposure to drug.
- Can go through withdrawal symptoms (usually the opposite effects of drug)
Addiction
pattern of behavior in which use of drug becomes a central role in a person’s life
Schedule I Drugs
No approved medical use and high abuse potential. Cannot be prescribed (Heroin, LSD, hallucinogenic mushrooms)
Schedule II Drugs
significant abuse potential. Can be prescribed (most heavy duty opioids)
Adjuvant Drugs
- Not classical analgesics but useful either alone or in combination with other agents for pain.
- Includes Corticosteroids, Disease Modifying Antirheumatic Drugs (DMARDSs) and Immunomodulators.
How are adjuvant drugs useful for pain management?
-Act on various components of the immune system
- useful in treatment of inflammatory and autoimmune disorders (ex. rheumatoid arthritis and lupus erythematosis).
- Can have powerful analgesic effects.
Antidepressants
- Adjuvant Drugs
- Amitriptyline, Duloxetine
- Alleviate symptoms of depression that commonly occur in patients with chronic pain.
- Enhance analgesic effects of opioids.
- beneficial in treatment of neurogenic pain.
Anticonvulsant Drugs
- Adjuvant Drugs
- Carbamazepine, Gabapentin, Pregabalin
- Useful in the management of neurogenic pains.
Duloxetine main mechanism of action
inhibits synaptic reuptake of serotonin and norepinephrine
Ketamine Adverse effects
- Potential “dissociative” psychiatric effects
- Cardiac Stimulation can be severe
Ketamine
- Similar to Phencyclidine (PCP)
- Widely used military in emergency trauma situations
- Lower doses being used increasingly in Pain management and psychiatry
General Principles for drug selection
- Assessment of type and level of pain
- if possible, treat or remove cause of pain
- Select appropriate drug for type and level of pain (Consider health status of patient assess potential side effects and potential toxicities)
- Use proper doses
- Consider legal issues related to opioid use
Drugs selected for mild pain
- Acetaminophen
- Aspirin
- Ibuprofen, ketoprofen, naproxen
Drugs selected for moderate pain
- Oral NSAIDs for arthritis, musculoskeletal, post surgical and dental pain
- Intermediate Potency Opioids (Codeine, Hydrocodone, etc.). Usually given in combination with acetaminophen or aspirin.
- Mixed agonist antagonist opioids like tramadol can also be used
Drugs Selected for Severe Pain
- Strong Opioids (morphine, oxycodone, hydromorphone, fentanyl, methadone, etc.) either alone or in combination with other agents.
- NSAIDs
- Adjuvant drugs such as antidepressants, anticonvulsants
Cost of treatment vs Cost of inadequate pain management
- Treatment - Cost of Patient evaluation and assesment, cost of medications, and costs of asministering meds/monitering patients (easy to determine)
- Inadequate/Inappropriate Pain management - Cost of increased morbidity in patients (ER visits, prolonged stays, lost time), costs from use of inappropriate drugs (health problems), and cost of human suffering (difficult to determine)
