Chapter 36: Pain Management

Introduction

  • Pain is the most common reason for seeking healthcare.

  • Both acute and chronic pain affects more individuals than diabetes mellitus, cancer, and cardiac disease combined, yet remains undertreated (Mazanec et al., 2021).

  • Estimates indicate that 20.5% of adults in the United States suffer from chronic pain (Yong et al., 2021).

  • Globally, around 5.5 billion people experience pain due to insufficient or no treatment (Kunnumpurath et al., 2018).

LO 36.1 The Concept of Pain

  • Pain includes physical and emotional aspects.

  • Margo McCaffery’s 1968 definition: "Pain is whatever the person with the pain says it is and that it exists whenever the person says it does," allowing for personal interpretation (Pasero & McCaffery, 2011).

  • The International Association for the Study of Pain (IASP, 2021) defines pain as:
      - "An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage."

  • Key notes about pain:
      - Pain is a personal experience influenced by biological, psychological, and social factors.
      - Pain and nociception are distinct phenomena; inferred solely from sensory neuron activity is incorrect.
      - Life experiences shape individual concepts of pain.
      - Reports of pain experiences should be respected.
      - While usually adaptive, pain may adversely affect function and well-being.
      - Verbal descriptions are not the only way to express pain; nonverbal communication also indicates pain experience.

  • Examples of pain:
      - Protective role: reflex withdrawal from a hot surface.
      - Result of injury: pain from a fractured hip.

LO 36.2 Nursing and Pain Management

  • Long-term disability often results from chronic pain (NIH, 2020).

  • Increasing elderly population will elevate needs for pain management regarding:
      - Back disorders
      - Degenerative joint diseases
      - Rheumatologic and visceral diseases
      - Cancer

  • Pain is highly subjective; influenced by cognitive, affective, behavioral, and sensory factors.

  • Essential knowledge for nurses:
      - Understanding personal attitudes and expectations about pain
      - Recognizing the importance of individualized pain management

  • American Nurses Association (2018) position statement on pain management includes:
      - Ethical responsibility to relieve pain
      - Individualized interventions are necessary
      - Use of the nursing process is required for improved pain management
      - Multimodal and interprofessional approaches are crucial
      - Evidence-informed modalities should be utilized
      - Advocating for access to effective pain management methods is crucial
      - Nurse leadership is needed to confront the opioid epidemic

  • The Joint Commission (2001) established standards for pain management due to undertreatment; mandated regular pain assessment.

  • Nurses are responsible for comprehensive pain assessments using tools and documenting patient responses pre- and post-intervention.

  • Standards were updated in 2018 to enhance pain assessment and management and deal with the opioid crisis (TJC).

LO 36.3 Normal Structure and Function

  • The nature of pain is complex and multifaceted, potentially serving as:
      - A protective mechanism
      - A warning signal
      - An unmet need
      - A malfunction of the nervous system due to disease

  • Pain arises from various factors:
      - Thermal, mechanical, chemical injuries, or ischemic pain

  • Processing occurs through peripheral and central nervous systems.

  • Key components in pain transmission include:
      - Nociceptors: Free nerve endings responsive to thermal, mechanical, or chemical stimuli.
        - Highest density in skin, moderate in joints, lower in internal organs.

Nociception

  • Nociception is defined as the process of carrying tissue injury signals from the periphery to the CNS.

  • The four phases:
      1. Transduction: Nociceptors convert painful stimuli to electrical impulses at the injury site.
          - Inflammatory response releases neurotransmitters (e.g., bradykinin, substance P) amplifying pain.
      2. Transmission: Pain impulses are transmitted from peripheral nerves to the spinal cord and brain via A-delta and C fibers.
      3. Perception: Translated by the brain into pain recognition; involves the somatosensory cortex, limbic system, and frontal cortex.
      4. Modulation: Brain can alter pain perception through inhibitory signals; endogenous opioids reduce pain impulse transmission by binding to receptors.

Pain Theories

  • Specificity Theory: Developed by von Frey; identifies four skin sensations & basis of pain receptors and pathways.

  • Sensory Interaction Theory: Proposed by Noordenbos; suggests larger-diameter nerve fibers inhibit smaller fibers, determining pain sensation.

  • Gate Control Theory (Melzack & Wall, 1965): Proposes a gating mechanism in the spinal cord that determines whether painful stimuli are transmitted to the brain, influenced by emotional and cognitive factors.

  • Neuromatrix Theory (Melzack, 2001): Proposes pain as a multidimensional, unique experience interlinked with personal history and experiences.

Types of Pain

  • Classified by:
      - Cause (cancer vs. noncancer pain)
      - Physiology (nociceptive vs. neuropathic pain)
      - Duration (acute vs. chronic)

  • Acute Pain: Lasts less than 3-6 months, caused by tissue injury.

  • Chronic Pain: Lasts more than 3 months post-surgery or more than 6 months. Associated with serious underlying health issues.

  • Nociceptive Pain: Caused by injury/inflammation to somatic and visceral tissues; characterized as sharp, aching, etc.
      - Includes referred and radiating pain.

  • Neuropathic Pain: Results from nerve injury, characterized as burning or shooting pain.

  • Psychogenic Pain: Perceived pain without identifiable physiological cause.

LO 36.4 Altered Structure and Function

  • Pain perception is affected by:
      - Physiologic changes, age, gender, emotions, cognitive differences, and sociocultural factors.

  • Neurological injuries alter perception; may include reliance on nonverbal cues in noncommunicative patients.

Physiologic Alterations Caused by Pain

  • Stress responses result from acute pain signaling.

  • Pain activates the sympathetic nervous system first:
      - Increased cortisol release, altering metabolism (leading to hyperglycemia).
      - Cardiovascular responses include increased heart rate and risk for myocardial infarction.
      - Respiratory responses may limit deep breathing, increasing pneumonia risk.
      - Musculoskeletal effects include impaired function and increased fatigue.
      - Gastrointestinal responses range from decreased motility leading to constipation to increased secretions.
      - Impaired immune function may provoke persistent pain.

Factors Influencing Pain

  • Individual factors also shape pain perception:
      - Differences in age, gender, culture, and more
      - Attitudes towards pain impact treatment compliance and outcomes.

  • Neurophysiological abnormalities can lead to false signals of pain, and unresolved psychological pain may result in mental health issues.

Current Research

  • Suggests personalized pain management approaches based on genetic predispositions to analgesic responses.

Assessment of Pain

  • Completion of thorough, individualized assessments is crucial.

  • Pain intensity scales (e.g., NRS, Wong-Baker FACES) are effective tools for assessment.

  • Health history must cover pain characteristics (location, duration, severity).

  • Emergent cases require focus on pinpointing and assessing pain rapidly.
     

Pain Assessment Tools

  • Multiple tools available including cognitive and noncognitive scales.

  • The self-reported pain is the best indicator.

Nursing Process and Pain Management

  • Holistic, patient-centered care utilizing pharmacologic and nonpharmacologic techniques is imperative.

  • Implementation and Evaluation: Ongoing assessment and adjustment of plans based on patient feedback to achieve pain management goals.

Barriers to Adequate Transitions to Management

  • Various personal and institutional barriers obstruct effective pain treatment including systemic apprehensions around opioids.

  • Personal fears and beliefs can hinder patients from seeking adequate pain management

Pharmacologic Pain Management

  • Key roles: assessing pain, administering medications accurately, and educating patients.

  • Several routes of administration exist based on individual needs.

Nonopioid Analgesics:

  • Include acetaminophen and NSAIDs.
     ### Opioid Analgesics:

  • Effective for moderate to severe pain, acting on opioid receptors, come with risks of tolerance and dependence.
     ### Patient-Controlled Analgesia (PCA):

  • Allows patients autonomy in managing pain, with careful monitoring required.

Complementary and Alternative Therapies

  • Incorporation of nonpharmacologic strategies is encouraged alongside medication approaches for holistic pain management (e.g., massage, meditation, biofeedback).

Evidence-Based Practice for Pain Management

  • Emphasize adherence to nursing standards and ethical considerations in pain management, ensure adequate pain care, navigating complex dimensions in patient care regarding pain regardless of addiction status.