Acute Pain

Question 1

What is acute pain and how long does it usually last?

Answer 1

Acute pain is a type of long-lasting pain that may or may not require clinical intervention. It usually subdues within a few days after the cause of pain is resolved, but can persist for weeks if it necessitates medical attention. It becomes chronic pain if it lasts longer than three months.

Question 2

What are some examples of acute pain conditions?

Answer 2

Examples of acute pain include pain from tooth extraction, inflammation of respiratory passageways during a viral infection, post-traumatic pain, post-surgery pain, and burn injury pain. These types of pain may persist for weeks and require continuous medical attention.

Question 3

When does acute pain become classified as chronic pain?

Answer 3

Acute pain is classified as chronic pain when it persists for longer than three months, which is an arbitrarily agreed period for categorizing pain as either acute or chronic.

Question 4

What are three major types of acute pain necessitating clinical interventions?

Answer 4

The three major types of acute pain necessitating clinical interventions are post-traumatic pain, post-surgery pain, and burn injury pain. These conditions may require continuous medical attention and have a risk of transforming into chronic pain.

Question 5

What are the three phases of acute pain?

Answer 5

The three phases of acute pain are:

Emergency phase: Between injury and stabilization, characterized by nociceptive pain from tissue damage, anxiety, and fear.

Healing phase: Lasts several weeks, characterized by fluctuating background pain, breakthrough pain from therapeutic interventions, and potential PTSD.

Rehabilitation phase: The longest phase, with pain becoming more localized, deep, and aching.

Question 6

What are the physiological mechanisms involved in acute pain

Answer 6

The mechanisms involved include direct stimulation of C and A-delta nociceptors, primary hyperalgesia, secondary hyperalgesia, sympathoadrenal activation, and neuroendocrine responses.

Question 7

How does direct stimulation of nociceptors occur in acute pain?

Answer 7

Direct stimulation of nociceptors occurs due to tissue disruption from cutting, tearing, pressure, or heat. In burn injury patients, pain results from environmental exposure, debridement procedures, and physiotherapy. Surgery can also cause nociceptor stimulation, leading to muscle contractions and reduced ventilation.

Question 8

How does primary hyperalgesia manifest in acute pain?

Answer 8

Primary hyperalgesia involves a decreased pain threshold in C and A-delta nociceptors to heat and mechanical stimuli near the injury site. It is caused by ions like H+ and K+, local mediators (bradykinin, serotonin, histamine), substance P, and pro-inflammatory cytokines (e.g., interleukin 1-beta, interleukin 6). Primary hyperalgesia develops within minutes after injury.

Question 9

What is secondary hyperalgesia and its phases?

Answer 9

Secondary hyperalgesia occurs in non-traumatized tissues surrounding the injury. It has two phases: an initial phase characterized by strengthened firing in wide-dynamic-range neurons (wind-up) and a long-term potentiation phase with prolonged enhanced responses. The long-term potentiation phase starts 15-20 minutes after injury and outlasts the initial nociceptive stimulation.

Question 10

What role do excitatory neuromediators play in secondary hyperalgesia

Answer 10

Excitatory neuromediators such as glutamate and N-methyl-D-aspartate (NMDA) receptors play essential roles in secondary hyperalgesia. These mediators contribute to the central nervous mechanisms underlying secondary hyperalgesia.

Question 11

What is the sympathoadrenal response to acute pain?

Answer 11

The sympathoadrenal response is a physiological adaptation to stress involving activation of the hypothalamus and sympathetic neurons, leading to increased heart rate, respiration, and blood flow in muscles and brain. This response aims to support tissue repair and survival but may impair healing by reducing blood flow to injured areas.

Question 12

How does the sympathoadrenal response affect acute pain patients

Answer 12

Activation of the sympathoadrenal system aggravates pain by sensitizing nociceptors. Reduced blood flow in injured areas impairs healing, increases muscle spasms, and can cause visceral ischemia, which further increases pain.

Question 13

What is the neuroendocrine response to acute pain?

Answer 13

The neuroendocrine response involves increased secretion of catabolic hormones like cortisol, glucagon, growth hormone, and catecholamines, which increase energy availability but may impair healing and cause muscle wasting and immunosuppression if prolonged.

Question 14

What role do interleukins play in the neuroendocrine response to acute pain?

Answer 14

Interleukins (e.g., IL-1 beta, IL-6) stimulate the secretion of adrenocortical hormones, contributing to the neuroendocrine response to acute pain. This response is characterized by increased levels of catabolic hormones to cope with injury.

Question 15

How do individual characteristics affect responses to acute pain?

Answer 15

Factors like age, sex, ethnicity, cultural background, anxiety, pain catastrophizing, locus of control, and history of substance abuse all influence responses to acute pain and management strategies.

Question 16

How does age affect acute pain?

Answer 16

Elderly people show decreased functioning of the fast A-delta nociceptive system and diminished transmission in the central nervous system, which correlates with lower post-operative opioid consumption.

Question 17

How does sex influence acute pain?

Answer 17

Females generally show increased pain sensitivity compared to males but tend to have a better response to opioid treatment, requiring lower doses of morphine.

Question 18

What role do ethnic and cultural factors play in acute pain?

Answer 18

Ethnic and cultural factors influence pain response along the lines of stoicism-emotiveness, affecting how patients express pain and their consumption of analgesics, though these roles are not fully understood.

Question 19

What is the role of anxiety in acute pain?

Answer 19

State anxiety significantly influences acute pain levels, as shown in studies where higher state anxiety correlated with increased pain severity after surgery

Question 20

what is pain catastrophising and its effect on acute pain?

Answer 20

Pain catastrophizing is the tendency to expect the worst outcomes for any pain. High catastrophizers experience greater pain intensity and report more difficulties in recovery compared to low catastrophizers.

Question 21

what is locus of control and how does it affect acute pain management?

Answer 21

Locus of control refers to a person’s perception of control over outcomes. Patients with an internal locus of control respond better to active coping strategies and patient-controlled analgesia, whereas those with an external locus are more dependent on caregivers.

Question 22

How does a history of substance abuse affect acute pain management?

Answer 22

Patients with a history of substance abuse may have increased tolerance to opioids, requiring larger doses for pain relief, though health care professionals may limit opioid use to avoid promoting drug-seeking behaviour.

Question 23

What psychological interventions are used for acute pain?

Answer 23

Interventions include attentional distraction, hypnosis, and cognitive-behavioral therapy. These methods are used to reduce pain perception by engaging attention away from pain or altering pain processing.

Question 24

How does attentional distraction help mitigate acute pain?

Answer 24

Attentional distraction involves diverting attention from pain by engaging in activities like watching TV, playing video games, or using virtual reality. Studies have shown that distraction significantly reduces pain intensity during painful procedures.

Question 25

How is hypnosis used in acute pain management?

Answer 25

Hypnosis can be used as an adjunct to local anesthesia to reduce physiological distress during surgery. It helps avoid the need for general anesthesia and is often part of cognitive-behavioral therapy programs.

Question 26

What is PTSD in the context of acute pain?

Answer 26

PTSD can develop in patients with acute pain from trauma or burn injury. It involves re-experiencing the traumatic event, avoiding triggers, sleep disturbances, hypervigilance, and exaggerated startle responses. Psychological support is crucial for managing PTSD symptoms in these patients.

Question 27

What psychological challenges do burn injury patients face during recovery?

Answer 27

Burn injury patients may face psychological shock, confusion, PTSD, sleep disturbances, and long-term psychological distress due to prolonged hospitalization, disability, and changes in body image. Psychological intervention focuses on allowing patients and their families to express worries, emphasizing strengths, and pointing to positive values of life.