Pharm Week 11 Objectives Hard

Factors Related to Undertreatment of Pain

• Patient-related and provider-related factors can contribute to the undertreatment of pain

Patient-Related Factors

• Fear of Addiction: Patients may avoid pain medication, especially opioids, due to addiction concerns
• Cultural and Social Beliefs: Some view enduring pain as a sign of strength, which discourages them from seeking treatment
• Lack of Communication: Patients may downplay or not effectively communicate the severity of their pain to avoid appearing weak
• Fear of Side Effects: Concerns about nausea, drowsiness, and long-term medication effects can result in treatment refusal
• Cognitive Impairments: Older adults or those with cognitive conditions like dementia may struggle to express pain, leading to undertreatment

Provider-Related Factors

• Bias and Stereotypes: Healthcare providers may underestimate pain in certain groups like racial minorities, women, or older adults, causing treatment disparities
• Lack of Proper Training: Some providers may lack adequate training in pain management or the latest guidelines, which can lead to inappropriate treatment
• Fear of Opioid Misuse: Due to the opioid crisis concerns, providers may be overly cautious in prescribing pain medications, even when necessary
• Time Constraints: In fast-paced healthcare settings, providers may lack sufficient time for thorough pain assessments, resulting in inadequate treatment
• Subjective Assessment: Relying solely on a patient's verbal report, a subjective experience, may lead to underestimation, particularly in nonverbal individuals
• Emphasis on Non-Opioid Alternatives Without Adequate Support: Promoting non-opioid treatments may not always be effective or accessible for all patients, resulting in untreated pain

Pain Threshold vs. Pain Tolerance

• Pain threshold is the minimum intensity at which a person starts to perceive pain
• Pain tolerance is the maximum pain level a person can endure before it becomes unbearable
• Pain threshold is measured as the point when a stimulus (heat, pressure) starts to feel painful
• Pain tolerance is measured as the highest pain intensity an individual can tolerate before needing relief
• Pain threshold is generally similar across individuals with minor variations
• Pain tolerance is highly variable, and influenced by psychological, cultural, and personal factors
• Pain threshold is influenced by physiological factors, such as nerve sensitivity and receptor function
• Pain tolerance is influenced by emotional state, past experiences, cultural background, and mental resilience
• An example of pain threshold is when a person starts feeling pain when a hand is placed in ice water at a specific temperature
• An example of pain tolerance is how long a person can keep their hand in the ice water before needing to remove it
• Pain threshold focuses on when pain starts, and pain tolerance focuses on how much pain can be endured
• Pain threshold is relatively stable across individuals, but pain tolerance varies significantly from person to person
• Pain tolerance can be influenced by stress, fatigue, or psychological state, but pain threshold is more biologically determined

Methods Used in Pain Assessment

• A patient's description of their pain is the cornerstone of pain assessment
• Asking the right questions and listening carefully to the answers helps ensure an accurate report of pain
• Asking about onset and temporal pattern, location, quality, intensity, modulating factors, previous treatment, and impact helps with pain assessment
• Physical and Neurologic Examinations help further characterize the pain, identify its source, and identify complications related to the underlying pathology
• Examining the pain site and determining whether palpation or manipulation makes it worse helps assess pain
• Nonverbal cues, such as protecting a painful area or limited movement, help indicate pain
• Diagnostic Tests, including imaging studies, neurophysiologic tests, and tests for tumor markers that help assess pain
• Ensure abnormalities identified in diagnostic tests explain the patient's pain
• Psychosocial Assessment: Assesses the impact of significant pain in the patient's past
• Psychosocial Assessment also evaluates the patient's usual coping responses to pain and stress
• Psychosocial Assessment gathers the patient's preferences regarding pain management methods
• Psychosocial Assessment takes note of the patient's concerns about using opioids, anxiolytics, and stimulants
• Psychosocial Assessment detects changes in the patient's mood (anxiety, depression) caused by cancer and pain
• The impact of cancer and its treatment on the family needs to be addressed, as well as the level of care the family can provide
• Psychosocial Assessment identifies the potential need for outside help, like palliative care or hospice
• Pain Intensity Scales: Descriptive and numeric scales for adults and older children are used to assess pain
• The pain affect FACES scale is used for young children and cognitively impaired patients who may have difficulty understanding the descriptive and numeric scales

Effects of Mu (µ) Receptor Activation

• The mu receptor is the most clinically significant opioid receptor
• Mu receptors are primarily responsible for analgesia and opioid-related side effects
• Strong pain relief, particularly for severe pain, is an effect of Mu Receptor Activation
• Stimulation of the reward system leads to a sense of well-being or euphoria, contributing to the addictive potential of opioids
• Respiratory depression, which inhibits brainstem respiratory centers slows or suppresses breathing
• Respiratory depression from Mu Receptor activation is a primary cause of opioid overdose fatalities
• Sedation is a general drowsiness and mental clouding can also occur from Mu Receptor activation
• Miosis (pupil constriction), which leads to small, pinpoint pupils due to parasympathetic activation from Mu Receptor activation
• Decreased gastrointestinal motility (constipation) slows intestinal movement, leading to opioid-induced constipation (OIC)
• Physical Dependence and Addiction: Chronic Mu Receptor activation can lead to tolerance, dependence, and withdrawal symptoms
• Bradycardia and Hypotension: Effects of Mu Receptor Activation may cause slowed heart rate and low blood pressure
• Examples of Mu Receptor Agonists: Morphine, Fentanyl, Oxycodone, Hydromorphone, Heroin converted to morphine in the body

Карра (κ) Receptor Activation

• Kappa receptors contrast with mu receptors, that often produce moderate analgesia but with fewer addictive properties
• Kappa receptors provides moderate pain relief, more effective for visceral and spinal pain
• Kappa receptor activation causes dysphoria, hallucinations, and paranoia, unlike mu activation
• Kappa receptor stimulation causes less intense drowsiness, than mu receptor activation
• Kappa receptor activation causes increased urine output due to inhibition of antidiuretic hormone (ADH)
• Kappa receptor causes less pronounced pupil constriction than mu receptor activation
• Kappa agonists do not significantly suppress breathing, making them safer in terms of overdose risk
• Kappa agonists are less addictive than mu agonists
• Examples of Kappa Receptor Agonists: Butorphanol, Pentazocine, Nalbuphine and Salvinorin A

Comparison of opiate receptor activation and impacts

• mu activation is better for pain relief, but carries higher risk
• kappa activation provides moderate pain relief with fewer associated risks

Major Adverse Effects Related to Narcotic Opiate Analgesics

• sedation and drowsiness are common CNS effects that cause sleepiness and increase risks of falls and accidents
• euphoria is a pleasurable sensation that contributes to opioids' addictive potential
• cognitive impairment affects memory, attention, and decision-making, especially in chronic users
• respiratory depression is the most dangerous adverse effect, leading to slow and shallow breathing
• respiratory depression is a leading cause of opioid overdose deaths
• constipation is a major side effect due to decreased gut motility
• nausea and vomiting are common in the initial stages because of the stimulation of the chemoreceptor trigger zone (CTZ) in the brain
• hypotension and bradycardia are potential cardio effects, especially with high doses
• opioid induced hormonal imbalances can reduce testosterone and estrogen levels, leading to decreased libido, menstrual irregularities, and osteoporosis
• opioids weaken the immune system, making patients more prone to infections
• common withdrawal symptoms include flu-like symptoms, GI distress, muscle pain/tremors, and severe anxiety

Therapeutic Uses of Opioid Analgesics

• Opioids manage trauma, post-surgical, and severe pain
• Opioids are prescribed for cancer pain/palliative care when other analgesics fail
• Opioids are adjuncts to anesthesia for sedation and analgesia
• Opioids, like codeine, reduce cough reflex
• Opioids manage diarrhea by decreasing intestinal motility, like with Loperamide and Diphenoxylate

Agonists, Agonist-Antagonists, and Antagonists

• Pure opioid agonists produce strong analgesia
• Mixed Agonist-Antagonists activate Kappa receptors with moderate pain relief
• Prototypes of Opioid Antagonists compeletely block opioid receptors to reverse opioid effects

Side Effects, Adverse Effects, and Precautions Associated with Opioid Narcotics

• Common side effects include sedation, drowsiness, constipation, nausea, and mild euphoria
• Adverse effects includes respiratory depression, QT prolongation, and hormonal imbalance
• Monitor for depression/misuse and respiratory depression

Narcotic Overdose Signs and Symptoms

• Respiratory Depression: Slow, shallow, or stopped breathing (most fatal effect)
• Unresponsiveness (Coma): Extreme drowsiness, inability to wake up, or deep unconsciousness
• Miosis (Pinpoint Pupils): Constricted, tiny pupils that do not respond to light

ASA Precautions

• Contraindicated in children due to risk of Reyes syndrome
• Should be stopped one week before surgery

Salicylism

• Signs include tinnitus, sweating, hyperthermia
• Treatment includes activated charcoal and IV fluids
• Toxic overdose of ASA