Pain, temp, mh

Phases of pain: transduction, transmission, perception, and modulation.

Transduction: begins when tissue is damaged by exposure to chemical, mechanical, or thermal noxious stimuli and is converted to electrophysiologic activity

Transmission: conduction of pain impulses along the
A and C fibers into the dorsal horn of the spinal cord and eventually to the reticular formation, hypothalamus, thalamus, and limbic system

Perception: is the conscious awareness of pain (in the brain)

Sensory-discriminating system, affective-motivational system, cognitive-evaluative system

Modulation: process of increasing or decreasing transmission of pain signals throughout the nervous system

Myelinated A-delta fibers: transmission is fast and causes reflex withdrawal of affected body part from stimulus before pain sensation is perceived.

Unmyelinated C polymodal fibers: stimulated by mechanical, thermal, and chemical nociceptors. Transmission is slower and conveys dull, aching, or burning sensations.

Pain threshold: Is the lowest intensity of pain that a person can recognize. Intense pain at one location may increase the threshold in another location.

Pain tolerance: Is the greatest intensity of pain that an individual can endure. Is very individualized; varies greatly among people and in the same person over time.

Segmental inhibition: A-beta fibers stimulated and impulses arrive at same spinal level as A-delta or C fiber impulses. Inhibitory interneuron. Decreases pain transmission.

somatic pain: Arises from joints, muscle, bone, and skin.

visceral pain: Transmitted by C fibers and pain arises from the internal organs and lining of body cavities. Pain is poorly localized as a result of the fewer number of nociceptors. Pain is aching, gnawing, throbbing, or intermittent in quality.

neurogenic pain: Is the result of primary lesion or dysfunction in nervous system. Is most often chronic. Burning, shooting, shock like, tingling. Hyperalgesia and allodynia

referred pain and common sites of referred pain: Pain in an area is removed or distant from its point of origin. Area of referred pain is supplied by the same spinal segment as the actual site. Can be acute or chronic.

Pediatric pain: Nociceptor system is functional by 20−24 weeks’ gestation.

Phases of sleep: Rapid eye movement (REM) sleep. Non–rapid eye movement (NREM) sleep.

NREM sleep: N1: Light sleep, 3%−8% of sleep time. N2: Longest stage, 45%−55% of sleep time. N3: Slow-wave sleep, 13%−23% of sleep time.

REM is 20%−25% of sleep time. Is also known as paradoxical sleep as the EEG pattern is similar to that of a natural awaken pattern where the brain is very active with dreaming. Vivid dreaming occurs during REM. Occurs every 90 minutes, beginning after 1−2 hours of sleep.

Insomnia: inability to fall or stay asleep

Obstructive sleep apnea syndrome: disorder of breathing during sleep, related to an upper airway obstruction associated with reduced blood oxygen saturation and hypercapnia.

Restless leg syndrome: unpleasant sensations (prickling, tingling, crawling) that occur at rest and are worse in the evening or at night.

Obesity hypoventilation syndrome: due to leptin resistance.

acute pain: Is a protective mechanism. Alerts an individual to a condition or experience that is immediately harmful to the body. Lasts less than 3 months. Clinical manifestations Sympathetic nervous notable. Tachycardia, hypertension, diaphoresis, dilated pupils. Anxiety.

chronic pain: Lasts at least 3 months; is poorly understood. Does not respond to usual therapy. Serves no protective purpose. Thought to be caused by dysregulation of nociception and pain modulation processes (peripheral and central sensitization) so not easily controlled. Neuroplasticity: maintenance of pain (brains ability to form and reorganize synaptic connections in response to learning or experience). May cause behavioral and psychologic changes, such as depression and anxiety. Suffering usually increases with time.

How is temperature regulated in the body: Is controlled by the hypothalamus. Heat is distributed by the circulatory system. Heat is produced by chemical reactions of metabolism and skeletal muscle tone and contraction.

Heat loss: Vasodilation

Heat conservation: vasoconstriction

Pediatric temperature: Infants produce sufficient body heat (brown fat) but are unable to conserve the heat produced. Small body size and high body surface-to-weight ratio. Inability to shiver. Thin subcutaneous layer. Must keep warm.

Aging considerations: Blood circulation and vasoconstriction/vasodilator responses are slowed. Metabolic rate is decreased. Shivering is decreased and ineffective. Sweating and the perceptions of heat and cold are decreased.

Fever: Temporary resetting of the hypothalamic thermostat.

Benefits of fever: Aids infectious response. Kills many organisms. Decreases the serum levels of iron, zinc, and copper. Deprives bacteria of food. Promotes lysosomal breakdown and auto destruction of cells. Increases lymphocytic transformation and phagocyte motility.

Tissue hypothermia: slows chemical reactions; increases blood viscosity and slows blood through the microcirculation; facilitates blood coagulation; stimulates vasoconstriction.

Accidental hypothermia: Is commonly the result of sudden immersion in cold water or prolonged exposure to cold. Passive or active rewarming can be used.

Therapeutic hypothermia: ATP is preserved. Is used to slow metabolism and preserve ischemic tissue during surgery, especially brain surgery.

Conductive hearing loss: Cannot be conducted through the middle ear.

Sensorineural hearing loss - can be caused by ototoxic drugs. Impaired organ of Corti or its central connections. Presbycusis: age-related hearing loss Mixed hearing loss.

Combination of conductive and sensorineural loses. Functional hearing loss. No organic cause.

Schizophrenia patho: Genetic predisposition. Monozygotic twins concordance rate: 30%–50%. Dizygotic twins or siblings concordance rate: 12%. Likely involvement of several genes located on different chromosomes. Prenatal and perinatal vulnerability factors. Exposure to prenatal infection; prenatal nutritional deficiencies; perinatal complications, such as birth defects and neonatal hypoxia; and upbringing in an urban environment. Neuroanatomic alterations. Enlargement of lateral and third ventricles; widening of frontocortical fissures and sulci. Reduction in the thalamus (may cause positive symptoms) and temporal lobe areas. Loss of cortical tissue. Low levels of reelin in the prefrontal cortex and hippocampus. Neurotransmitter alterations. Alteration of brain dopamine pathways. Glutamate hypothesis: under activation of glutamate receptors (acts on the N-methyl-d-aspartate [NMDA] receptor subtype).

Positive Schizophrenia symptoms: Frequently occur during a psychotic episode when the individual loses touch with reality and experiences something that should be absent. Hallucinations: perceptions are experienced without an external stimulation of the sense organs. Delusions: false beliefs are persistent. Disorganized behavior is exhibited. Disorganized speech: formal thought disorder; poverty of speech. Disorganized or bizarre behaviors.

Negative Schizophrenia symptoms: Characterized by disruptions in normal emotional states and expressions. Cognitive symptoms. Problems with thought processes. Inability to perform daily tasks requiring attention and planning. Negative dimensions. Flattened Affect- near absence of facial expressions or emotions. Anhedonia-cannot experience emotions like pleasure or pain and feel detached from environment. Alogia-absence of speech and the ability to answer questions or express themselves. Avolition-not able to complete simple goals or tasks like bathing or dressing.

Classifications: depression with mania (Bipolar I) or depression with hypomania (Bipolar II)

PTSD: persistent dysregulation of fear-based memory system. DSM 5 needs 6 symptoms: reexperience, avoidance, negative cognitions, and mood and arousal.

Depression patho: Neurochemical dysregulation. Deficits in norepinephrine, dopamine, and/or serotonin, leading to depression. Mania: elevated concentrations of monoamines. thyroid

Depression symptoms: Unremitting feelings of sadness and despair. Dysphoric mood. Sleep disturbances. Loss of appetite and body weight. Reduced interest in pleasurable activities and interpersonal relationships. Decreased concentration. Restlessness and agitation. Feelings of worthlessness and guilt. Suicidal thoughts.