Question 1

Where are the primary-order pain-transmitting neurons located within the spinal cord?

Accepted Answer

The cell bodies of the primary-order neurons, or pain-transmitting neurons, reside in the dorsal root ganglia just lateral to the spine along the sensory pathways that penetrate the posterior part of the cord. They are not in contact with lateral root, anterior root, or medial root ganglia.

Question 2

Which spinal tract carries the most nociceptive information?

Accepted Answer

Most nociceptive information travels by means of ascending columns in the lateral spinothalamic tract (also called the anterolateral funiculus). The paleospinothalamic tract is part of the lateral spinothalamic tracts and carries slow impulses for chronic pain. The other tract is the neospinothalamic tract which carries fast impulses for acute pain. The archeospinothalamic and dorsal spinothalamic tracts are not part of this system.

Question 3

Pricking one's finger with a needle would cause minimal pain, whereas experiencing abdominal surgery would produce more pain. This distinction is an example of which pain theory?

Accepted Answer

According to the specificity theory, a direct relationship exists between the intensity of pain and the extent of tissue injury. Pattern theory proposes that any somatic sense organs respond to a dynamic range of stimulus intensities. Different sense organs have different levels of responsiveness to stimuli. Gate control theory (GCT) integrates and builds upon features of the other theories to explain the complex multidimensional aspects of pain perception and pain modulation. Pain transmission is modulated by a balance of impulses conducted to the spinal cord where cells in the substantia gelatinosa function as a "gate." The spinal gate regulates pain transmission to higher centers in the CNS. There is no intensity theory of pain.

Question 4

Massage therapy relieves pain by closing the pain gate with the stimulation which fibers?

Accepted Answer

Massaging stimulates different Ab fibers to close the pain gate. Ad, B, and C fibers do not have a role in pain modulation.

Question 5

Which pain theory proposes that a balance of impulses conducted from the spinal cord to the higher centers in the central nervous system (CNS) modulates the transmission of pain?

Accepted Answer

The gate control theory (GCT) explains that a balance of impulses conducted to the spinal cord, where cells in the substantia gelatinosa function as a spinal gate, regulates pain transmission to higher centers in the CNS. Pattern theory proposes that any somatic sense organs respond to a dynamic range of stimulus intensities. Different sense organs have different levels of responsiveness to stimuli. According to the specificity theory, a direct relationship exists between the intensity of pain and the extent of tissue injury. Neuromatrix theory is an advancement of the gate control theory and proposes that the brain produces patterns of nerve impulses drawn from various inputs, including genetic, sensory-discriminative, affective-motivational, and evaluative-cognitive experiences.

Question 6

A patient's chart describes visceral pain. What does the healthcare professional understand about this term?

Accepted Answer

Visceral pain refers to pain in internal organs and the abdomen and is transmitted by sympathetic afferents. Visceral pain is poorly localized because of fewer nociceptors in the visceral structures. Sharp and well-defined pain describes acute pain. Somatic pain arises from muscle, bone, joints, and skin.

Question 7

A healthcare professional is caring for a patient who was rewarmed after suffering from hypothermia. What possible long-term complication will the professional continue to assess the patient for?

Accepted Answer

Rewarming can result in long-term complications that include congestive heart failure, hepatic and renal failure, abnormal erythropoiesis, myocardial infarction, pancreatitis, and neurologic dysfunctions. Short-term complications of rewarming include acidosis, rewarming shock, and dysrhythmias.

Question 8

The healthcare professor states that a patient has reached pain tolerance. What further information from the professor is most accurate?

Accepted Answer

Pain tolerance is the duration of time or the intensity of pain that an individual will endure before initiating overt pain responses. Consuming alcohol usually increases pain tolerance temporarily. Perceptual dominance causes pain at one site to mask pain at another site and is part of pain threshold. Pain threshold is the point at which a stimulus is perceived as pain.

Question 9

A healthcare professional is caring for a person who has experienced pain for 3 days. What signs would the professional note if the patient has anxiety in addition to the pain?

Accepted Answer

Anxiety is common in acute pain states and is usually apparent in the alterations of vital signs and can include elevation of blood sugar levels, decreases in gastric acid secretion and intestinal motility, and a general decrease in blood flow to the viscera and skin. Nausea occasionally occurs. Anxiety would not typically produce fever, weakness, fatigue, depression, constipation, or decreased blood pressure.

Question 10

Enkephalins and endorphins act to relieve pain by which process?

Accepted Answer

Enkephalins and endorphins are neurohormones that act as neurotransmitters by binding to one or more G protein-coupled opioid receptors and thus relieving pain. They do not inhibit cells in the substantia gelantinosa, stimulated descending efferent nerve fibers, or block transduction of nociceptors.

Question 11

Which endogenous opioid is located in the hypothalamus and pituitary and is a strong m-receptor agonist?

Accepted Answer

The synthesis and activity of b-endorphin is concentrated in the hypothalamus and the pituitary gland and act as strong m-receptor agonist. Enkephalins are the most prevalent of the natural opioids and bind to d opioid receptors. Enkephalins are concentrated in the hypothalamus, the PAG matter, the nucleus raphe magnus of the medulla, the dorsal horns of the spinal cord, but not the pituitary. Dynorphins are the most potent of the endogenous opioids binding strongly with k receptors to impede pain signals in the brain. They play a role in mood disorders and drug addiction and paradoxically in stimulating chronic pain. Endomorphins are dynorphins.

Question 12

Where is the gate in the gate control theory (GCT) of pain located?

Accepted Answer

The synaptic connections between the cells of the primary- and secondary-order neurons located in the substantia gelatinosa and other Rexed laminae function as a pain gate. The remaining options do not act in this function.

Question 13

Where is the major relay station of sensory information located?

Accepted Answer

Although the organization of all of the ascending tracts is complex, the principal target for nociceptive afferents is the thalamus, which, in general, is the major relay station of sensory information. The Ad and C fibers synapse in the laminae of the dorsal horn, cross over to the contralateral spinothalamic tract, and then ascend to synapse in the midbrain through the neospinothalamic and paleospinothalamic tracts. Impulses are then conducted to the sensory cortex. Descending pain inhibition is initiated in the cerebral cortex or from the midbrain and medulla. The hypothalamus has a major role in temperature regulation. A complex interaction of neural networks and neurotransmitters promote wakefulness and sleep. The hypothalamus, brainstem, and basal forebrain are involved in promoting wakefulness.

Question 14

Which type of nerve fibers transmits pain impulses?

Accepted Answer

Of the available options, only medium-sized Ad fibers transmit pain impulses. A-beta (Ab) fibers are large myelinated fibers that transmit touch and vibration sensations. They do not normally transmit pain but play a role in pain modulation. A-alpha (Aa) fibers and B fibers do not play any role in pain.

Question 15

Pain that warns of actual or impending tissue injury is referred to as what?

Accepted Answer

Acute pain is a protective mechanism that alerts the individual to a condition or experience that is immediately harmful to the body. Chronic pain lasts long beyond the time of an actual injury and serves no purpose. Pain is what each person says it is so there is no psychogenic pain. Phantom pain is a type of chronic pain where sensations are felt without the typical stimuli, and is seen in people who have had amputations.

Question 16

What part of the brain provides the emotional response to pain?

Accepted Answer

The limbic and reticular tracts are involved in alerting the body to danger, initiating arousal of the organism, and emotionally processing the perceived afferent signals, not just as stimuli, but also as pain. This system is in the anterior temporal lobe, not the parietal lobe. The thalamus is the major relay station of sensory information. The hypothalamus, brainstem, and basal forebrain are involved in promoting wakefulness.

Question 17

A healthcare professional is trying to lower a patient's body temperature by convection. What action by the professional will accomplish this?

Accepted Answer

Convection occurs through transfer of heat through currents of gas or liquid, so a fan blowing over the patient would accomplish this. Lowering the temperature in the room will aid heat loss through radiation. A cooling blanket and cold moist towels would provide heat loss through conduction.

Question 18

How does the release (increase) of epinephrine raise body temperature?

Accepted Answer

Epinephrine and norepinephrine produce a rapid transient increase in heat production by raising the body's basal metabolic rate. The other options are not correct descriptions of the effects of epinephrine on body heat.

Question 19

Where in the CNS does a person's learned pain response occur?

Accepted Answer

The cognitive-evaluative system overlies the individual's learned behavior concerning the experience of pain and can modulate the perception of pain and is mediated only through the cerebral cortex.

Question 20

A healthcare professional is working in a health tent at a marathon. A person enters the tent and reports profuse sweating for the last hour. How much fluid does the healthcare professional advise the person to drink to replace this fluid loss?

Accepted Answer

Sweating may cause as much as 2.2 L of fluid per hour to be lost. The best option is to have the person drink 2 L.

Quiz 16: Pain, Temperature Regulation, Sleep, and Sensory Function