Anesthesia/Analgesia Flashcards

(150 cards)

1
Q

What is the definition of suffering

A

“an experience of unpleasantness and aversion associated with perception of harm or threat of harm in an individual”

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2
Q

What is a primal alert signal

A

Linked to animals need to maintain homeostasis
Designed to alert animals to threats to these needs being met and drive aversive and adaptive behaviors

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3
Q

What are the four most common clinical signs associated with illness

A
  1. Fever 2. Lethargy 3. Anorexia, 4. Cachexia
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4
Q

What can sleep deprivation lead to

A

Systemic hypertension, higher mortality

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5
Q

What are 8 palliative measures in ICU for suffering

A

1) Provide adequate opportunity for uninterrupted sleep
-Low lighting overnight when feasible
2) Clustering treatments to minimize patient awakenings
3) Addressing thirst, hunger, and pain
4) Small amount of oral liquids to maintain membrane moisture -
5) Serial monitoring for pain
6) Vigilance for nausea
7) Nebulized furosemide may provide symptomatic relief from dyspnea as may opioid administration
8) Get patients outside for portion of the day to express normal behaviors

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6
Q

Definition of pain

A

an unpleasant sensory and emotional experience associated with actual or potential tissue damage.

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7
Q

10 consequences of uncontrolled pain

A
  1. increased blood pressure and heart rate
  2. peripheral vasoconstriction
  3. increased metabolic rate and oxygen consumption
  4. decreased immune function
  5. Immobility
  6. decreased pulmonary function and atelectasis
  7. increased incidence of pneumonia
  8. Inappetence
  9. Restlessness
  10. Insomnia
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8
Q

What is the four goal of treating pain

A
  1. relieve patient suffering
  2. promote healing
  3. decrease length of hospitalization
  4. minimize long-term changes to the animal
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9
Q

What are physiological 4 parameters of pain

A

HR, RR, BP and pupil dilation

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10
Q

What is a measurable physiologic parameter and how does it relate to pain

A

Heart rate variability: variation in R-R interval obtained on ECG

Changes in parasympathetic and sympathetic nervous system tone have bigger impacts on high and low frequency components

Low HRV suggests dominance of once branch of ANS , typically the SNS if the evaluation made during noxious stimulation, stress, exercise

Correlated to chronic pain but not acute pain

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11
Q

What are endocrine markers of pain

A

epinephrine, NE, and cortisol

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12
Q

What are 10 altered behaviors of animals when in pain? Give an example of each

A
  1. Posture
    -Hunched back, base-wide stance position, prayer position (neck and head extended forward with front of body lowered to the ground), head and/or tail tucked under the body, tension and rigidity of the painful area, frequent position changes, reluctance to assume normal body positions (e.g., will not lie down, sit or stand when they normally would)
  2. Gait
    -Stiff, lameness, reluctance to move
  3. Abnormal movements
    -Shaking, trembling

4.Interaction
Reducing willingness to interact with people

  1. Demeanor
    Some animals become aggressive, some submissive

6.Attention to painful area
-Looking and staring, guarding, licking, chewing, and biting, self mutilation

  1. Palpation to painful area
    Turn or flinch, withdrawal, or escaping effort to biting and aggression when applying pressure
  2. Vocalization
    -Altered vocalizatio patterns
  3. Appetite
    -hyporexia/anorexia
  4. Grooming
    -Excessive grooming or chewing
    -In cats appropriate grooming decreased
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13
Q

What are two types of pain scales

A

Unidimensional and Multidimensional

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14
Q

What’s a unidimensional pain scale and what are its cons

A

Simple descriptive scale, numeric rating, scale, and visual analog scale

Poor interobserver agreement and sensitivity

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15
Q

Name 7 multidimensional scales and which ones are not validated?

A

1) 4AVetscale (validated for orthopedic pain)

2) Glasgow composite measure pian score (CMPS-C)
-validated for acute pain

3) Glasgow composite measure pain score short form
-validated for acute postop pain

4) university of melbourne pain scale
-acute pain

5) CSU pain scale
-not validated

6) UNESP-botucatu Multidimensional composite pain scale for cats
-validated

7) Glasgow composite measure pain score feline
-validated

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16
Q

What is an action unit in pain

A

unique changes in facial expression produced by facial muscle activity
Involuntary and cannot be properly suppressed, amplified or stimulated

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17
Q

What are three AU’s in cats

A

Bases of pinane moving away, dorsal movement of the nose, mouth, and cheek area, and eyes narrowing

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18
Q

In a study of 351 dogs and cats hospitalized in the ICU, ___% were prescribed analgesics, and in __% of those cases, drug administration deviated from prescribed orders (__% decreased dose and ___% increased dose).

A

In a study of 351 dogs and cats hospitalized in the ICU, 39% were prescribed analgesics, and in 36% of those cases, drug administration deviated from prescribed orders (62% decreased dose and 38% increased dose).

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19
Q

In above study What were reasons in above study for decreased dosing

A

sedation, hypothermia, hypotension, perceived absence of pain, and lack of access to controlled drugs.

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20
Q

In above study what were reasons for increased dosing

A

perceived pain, vocalizing, and anxiety.

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21
Q

What % PCV is necessary for adequate oxygen carrying capacity and oxygen delivery?

A

> 25%

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22
Q

During anesthesia PCV can decrease by how much %?

A

3-5%

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23
Q

What anesthetic protocols should be considered and administered for patient with renal insufficiency

A

Higher fluid rate may be required to maintain renal perfusion
Drugs excreted by kidney (ketamine in cats) may have delayed excretion

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24
Q

What anesthetic protocols should be considered and administered for patient with hepatic disease

A

Anesthetic protocols may be affected due to decreased glucose and albumin production, altered drug metabolism via cytochrome P-450 and decreased production of coagulation factors

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25
What anesthetic protocols should be considered and administered for patient with cardiac disease
Avoid fluid overload Monitor BP carefully because hypotension may come from decompensation
26
MOA for anticholinergic?
competitively inhibits acetylcholine or other cholinergic stimulants at postganglionic parasympathetic neuroeffector sites
27
Side effects of anticholinergics?
May make secretions more viscous Increase anatomic dead space Increase heart rate Can increase myocardial work and oxygen consumption Increase IOP, pupillary dilation Glycopyrrolate does not cross blood–brain barrier or the placenta
28
Which U agonist has NMDA antagonist properties
Methadone
29
Pros and Cons of full u agonist
Complete reversal with naloxone Analgesic- good for chronic and neuropathic pain Minimal effect on CV performance Give anticholinergic drug before starting CRI Monitor for hyperthermia in cats Cause respiratory depression Cause bradycardia Reduce reuptake of norepinephrine and serotonin, possible serotonin syndrome morphine and meperidine cause histamine release => hypotension GI effects
30
Pros and cons of partial u agonist
Slow onset, effects difficult to reverse Good for moderate pain
31
Pros and cons of k agonist/u antagonist
Partial reversal of µ-agonist drugs Minimal CV effects Not good for severe pain
32
MOA of ketamine
binds N-methyl-D-aspartate (NMDA) receptors, reducing receptor activity and release of glutamate, an excitatory neurotransmitter
33
Pros and Cons of Ketamine
Cause salivation Increase heart rate, CO via centrally mediated sympathetic response and endogenous catecholamine release, usually CV sparing Increase ICP and intraoccular pressure Analgesic Renal elimination in cat Cautious use in cats with HCM b/c increased cardiac contractility Direct myocardial depressant effects in debilitated patients with decreased endogenous catecholamine response +. Hypotension and CV instability Potential seizure as sole agent doesn’t depress laryngeal protective reflexes and produces less ventilatory depression than opiods Prevents response to nociceptive stimulie carried by p ain neurons
34
MOA of benzodiazepines
antagonism of serotonin increased release of and/or facilitation of gamma-aminobutyric acid (GABA) activity diminished release or turnover of acetylcholine in the CNS.
35
MOA of phenothiazines
block postsynaptic dopamine receptors in the CNS and may inhibit the release of dopamine and increase its turnover rate alpha 1 receptor blockade
36
Pros and cons of phenothiazine
Vasodilatory Long duration of action Not analgesic
37
MOA of barbiturates
act directly on the CNS neurons in a manner similar to that of the inhibitory transmitter GABA
38
Pros and Cons of barbiturates
Cause cardiovascular depression Cause respiratory depression Provide rapid induction Decrease ICP and intraoccular pressure Effects may be potentiated by concurrent acidosis or hypoproteinemia
39
MOA of propofol
Potentiates the effects of gamma-aminobutyric acid (GABA; an inhibitory neurotransmitter) by decreasing the rate of dissociation of GABA from its receptors. This prolonged binding results in an influx of chloride, causing hyperpolarization of the postsynaptic cell membrane. Propofol may also have activity at the glycine and N-methyl-D-aspartate (NMDA) receptors, but this is unclear.
40
Pros and Cons of Propofol
Rapidly acting with short duration of action Causes respiratory depression Causes peripheral vasodilation Myocardial depressant Can create arrhythmias Not analgesic Use with caution in patients with volume depletion or cardiovascular compromise; can cause significant depression Increases ICP Can cause Heinz body anemia in cats
41
MOA of etomidate
Acts at the GABA receptor in the CNS to increase chloride conductance, causing hyper-polarization of postsynaptic neurons and resulting in hypnosis and CNS depression
42
Pros and cons of etomidate
Maintains cardiovascular stability Not used alone: otherwise retching and myoclonus Suppresses adrenocortical function for 2–6 hr following single bolus dose in cats repeated use => hemolysis due to propylene glycol
43
How are alpha 2 agonists metabolized
biotransformed by the liver, with inactive metabolites excreted in the urine
44
Pros and cons of alpha 2 agonist
Causes cardiovascular depression Can cause vomiting Provides good sedation and analgesia diuresis peripheral vasoconcstriction bradycardia muscle relaxation Can be combined with butorphanol or ketamine
45
MOA of alfaxalone
neuroactive steroid, binds to and activates the GABA cell surface receptor, inducing postsynaptic cell membrane hyperpolarization by activating chloride ion transport and enhancing the inhibitory action of GABA in the CNS.
46
How is alfaxalone metabolized
undergoes phase I (cytochrome P450-dependent) and phase II (conjugation-dependent) metabolism in both species.27 Cats and dogs form the same 5 phase I metabolites. Phase II metabolites in cats are alfaxalone sulfate and alfaxalone glucuronide, with only alfaxalone glucuronide found in dogs. Alfaxalone metabolites are likely to be eliminated from dogs and cats by hepatic/fecal and renal routes, which is similar to other species studied.
47
MOA of Lidocaine in analgesia
reducing ectopic activity of damaged afferent neurons, action at different molecular sites, such as Na+, Ca2+, and K+ channels and N-methyl-D-aspartate (NMDA) receptors.
48
MOA of inhalants
Acts on GAB receptors and voltage-gated channels
49
Pros and cons of inhalants
Produces dose-dependent cardiovascular depression and peripheral vasodilation Anesthesia depth can be adjusted rapidly Potential for hypoxemia Isoflurane and sevoflurane show rapid uptake and recovery Nitrous oxide should be used with caution with closed gas spaces
50
Why is propoflo 28 not recommended in ill cats
Has benzyl alcohol as preservative which can be toxic when given in large doses low capacity for glucuronic acid conjugation and therefore have limited ability to metabolize benzoic acid.
51
What drug should be avoided in splenic tumor/fracture patients and why?
acepromazine, thiopental, and propofol can result in splenomegaly.
52
What monitoring should you do during anesthesia?
Monitor ECG for changes in HR and rhythm MAP > 60 mmHG to maintain renal perfusion Perfusion parameters: CRT, MM, pulse quality Depth Oxygenation Capnography UOP Temperature Bloodwork (PCV/TP, BG in critical patietns)
53
What features do you look at in depth
eye position pupil size jaw tone response to stimulus heart rate blood pressure respiratory rate
54
Pulse ox will read less than 100% when PaO2 falls under ____
140 mmHg
55
Steps to trouble shoot intraoperative hypotension
First step decrease inhalant Next fluid bolus Inotropic/vasopressor support Add second agent
56
What is the goal of pain control?
state in which the pain is bearable but some of the protective aspects of pain, such as inhibiting use of a fractured leg, still remain
57
Where do opioids react (central, peripheral, transduction)?
centrally
58
MOA of naloxone
bind to the same receptor as agonists but cause no effect and can competitively displace the agonist from the receptor and therefore reverse the agonist effect
59
Which opioids reach a maximal effect at upper end of dose rang
butorphanol and buprenorphine
60
How is remifentanil metabolized
tisseu plasma esterases
61
Duration of action of fentanyl?
30 min an up to 2 hours when Im or SC
62
Adverse effects of simbadol
hyperthermia, hypotension, bradycardia, or tachycardia
63
Side effects of naloxone
acute pain, excitement, emergence delirium, aggression, and hyperalgesia
64
What's the benefit of using butorphanol as a reversal agent
that complete reversal of analgesia does not occur due to the κ-agonist effects of butorphanol. has sedative effects still
65
Why is buprenorphine not as easily reversed
difficult to displace form receptor
66
Draw arachidonic acid pathway
67
How do nsaids decrease pain
NSAIDs decrease the pain input to the CNS, which may aggravate central hypersensitivity. Inhibition of COX enzyme isoforms decreases inflammation
68
Which COX pathway responsible for basal prostaglandin production and normal homeostatic processes
Cox 1
69
Where are alpha 2 adrenergic agonists metabolized
biotransformed by the liver, with inactive metabolites excreted in the urine
70
Cons of atipamazole
abrupt hypotension and/or aggression
71
What can affect efficacy of fantanyl patch
Taken up by dermal blood flow Hair, obesity and hypovolemic or hypothermic patients can alter
72
What are adverse effects of bupivicaine
arrhythmias, reduced CO diaphragmatic paralsyis
73
How does nocita work
multi-vesicular liposomes encapsulating bupivacaine gradually released over several hours as the lipid bilayers break down
74
Adverse effects epidural
vasodilation and subsequent hypotension vomiting, urinary retention, pruritus, and delayed hair growth at the clipped epidural site
75
Contraindications for epidural analgesia
include trauma over the pelvic region (with loss of appropriate landmarks), sepsis, coagulopathy, CNS disease, skin infection over the site of injection, hypovolemic shock, and severe obesity.
76
Complications of epidural catheter
catheter dislodgement, discharge from the site, fecal contamination, line or filter breakage, and localized dermatitis.
77
Why do you use lower dose if epidural goes into subarachinoid space
The lower dose is sufficient for an analgesic response because the roots of the spinal cord are more accessible within the subarachnoid space, where they are not protected by the dura
78
Why is lidocaine beneficial to ischemia re-perfusion injury
inhibiting Na+/Ca2+ exchange and Ca2+ accumulation during ischemia, scavenging hydroxyl radicals, decreasing the release of superoxide from granulocytes, and decreasing polymorphonuclear leukocyte activation, migration into ischemic tissues, and subsequent endothelial dysfunction
79
What % of human patients will experience ICUAW and can be u to 6 months
As much as 50% of muscle strength can be lost within 1 week of immobility
80
What are benefits of rehabilitation therapy in critically ill patients
* Decrease loss of muscle mass and strength * Maintain functional ability * Decrease pain and inflammation * Improve healing time * Reduce edema * Improve ventilation and circulation * Positive psychological benefits * Prevent injury * Decrease hospitalization time * Guide post hospitalization home care
81
How does laser therapy work
photobiomodulation, involves the direct application of light energy (photons) to induce cellular responses in tissues photons are absorbed by the cytochrome c complex in the mitochondria of target cells, which results in a biological cascade of events, including accelerated production of ATP, nitric oxide, and reactive oxygen species reduces pain, inflamamtion, heals, improves muscle repair
82
Where are contraindicated areas of treatment for laser therapy
neoplastic lesions, near a pregnant uterus, gonads, or cornea, near the presence of active bleeding, the endocrine glands, and active epiphyses.
83
What's Transcutaneous Electrical Nerve Stimulation
TENS is the application of high-frequency electrical current through electrodes placed on the skin. TENS activates large cutaneous Aβ fibers, which is believed to stimulate inhibitory neurons in the spinal cord dorsal horn, interfering with transmission of C nerve fiber pain impulses to the brain (also known as the gate theory)
84
What is pulsed electromagnetic field therapy
a device that transmits a nonthermal electromagnetic field when applied over an area of tissue to reduce pain and inflammation increase intracellular Ca2+, which leads to increased calcium binding to calmodulin. It is believed that this reaction leads to a variety of downstream pathways, including the production of nitric oxide
85
Contraindications to pulsed electromagnetic field therapy
not advisable to apply PEMF over tumor sites of hemangiosarcoma due to a potential increase in blood flow. Similarly, it should not be used with animals that have a pacemaker because of potential electrical interference.
86
What is cryotherapy
application of cold to tissues, results in vasoconstriction, which decreases local blood flow, inflammatory response, and edema, thereby reducing pain Pain relieving effects are achieved by slowing of nerve conduction velocity, increasing pain threshold and pain tolerance
87
What is thermotherapy
Results in vasodilation, promotion of circulation of blood and lymphatics, edema reduction, release of muscular tension and spasm, pain reduction, and improved tissue elasticity
88
How does Prom help
diffusion of nutrients from synovial fluid to cartilage, improves circulation and flexibility, and reduces the tension of periarticular muscles. In patients with femoral fractures, PROM is required to prevent quadriceps
89
What are three kinds of massage
1.Stroking 2. Effleurage 3. Petrissage
90
What is stroking massage
slow gliding movement over the body using the palm of the hand in the direction of fur growth, cranial to caudal and proximal to distal
91
What is effleurage massage
helps with fluid mobilization and lymphatic drainage; the palms of the whole hand are used for long strokes with light to moderate pressure distal to proximal and along the direction of muscle fibers towards the flow of lymphatic and drainage back to the heart.
92
Where should
93
massage not be performed
areas of active infection or acute inflammation, near a tumor, over open wounds, in cases of deep vein thrombosis or coagulopathies, in patients with unstable fractures, over painful areas, in patients in shock, and animals adversely reactive to touch
94
What is neuromuscular electrical stimulation
low frequency, high pulse duration electrical stimulation to the muscles percutaneously through electrodes placed on the skin. The current acts on motor nerves to achieve muscle contraction.
95
When is neuromuscular electrical stimulation contra-indicated
pacemaker patients or seizure disorders Application is not recommended over areas of neoplasia, infection, impaired sensation or skin damage, thrombosis or thrombophlebitis, directly over the heart, carotid sinus, or trunk during pregnancy
96
Benefits of active movement
Active movement allows for natural joint motion and muscle contractions to maintain muscle strength and joint health
97
What are rehab options for pulmonary therapy
Positioning-alternating recumbency Postural drainage Pervussion
98
What is definition of pain
Unpleasant sensory and emotional experience associated with actual or potential tissue damage
99
What is nociception
Neural process of encoding noxious stimuli. Conscious perception of pain
100
What is physiologic pain
Noxious stimuli associated with the risk of injury Proportional to stimulus intensity Transient and characterized by a high stimulus threshold and narrow localization Protective; Induces withdrawal reflexes and avoidance responses
101
What is pathologic pain
Persistent noxious stimuli perpetuated by inflammation or nerve damage Implies that tissue damage has already occurred Exaggerated pain response (Hyperalgesia) either at the site of injury or surrounding areas (Extraterritorial pain)
102
What is adaptive pain
Transient normal response to tissue damage; confers tissue protection Encompasses physiologic and pathologic pain
103
What is maladaptive pain
Alteration of spinal cord and brain function from prolonged stimulus Decrease of peripheral threshold of nociceptor Altered neuronal gene expression and increased spinal neuron responsiveness Secondary to inadequate management of adaptive pain
104
What is allodynia
pain caused by a stimulus that doesn't normally result in pain
105
what is analgesia
absence of pain in response to stimulation that would normally be painful
106
Causalgia
syndrome of sustained burning pain, allodynia, and hyperpathia after a traumatic nerve lesion, often combined with vasomotor and sudomotor dysfunction and later trophic changes
107
What is distress
acute anxiety or pain
108
Dysphoria
state of anxiety or restlessness, often accompanied by vocalization
109
Hyperalgesia
Increased response to a stimulus that is normally painful
110
What is paresthesia
abnromal sensation, whether spontaneous or evoked
111
What is the Pathway of Nociception
Perception/Transduction -Nociceptors Transmission -sensorry nerve fibers Modulation -spinal cord and brain Conduction and central integration -pain perception
112
Draw pathway of nociception
113
What are the nociceptors in perception and transduction
Nociceptors in cutaneous tissue, muscles and viscera
114
What are the stimuli of nociceptors in perception and transduction
temperature, chemical ligands and mechanical shearing forces
115
How do nociceptors stimulate pain
Activation of nonselective ion channels gated = Na+/Ca+ ion influx Voltage-gated Na+ channel activated, leading to large Na+ influx and further depolarization
116
What are chemical ligands that initiate nociception
Chemical ligands: pH, prostaglandins, leukotrienes, capsaicin, bradykinins, serotonin, anandamide, olvanil, resiniferatoxin
117
What are the three transmission-sensory nerve fibers
Aβ fibers A δ fibers C fibers
118
What do Aβ fibers do?
Conducts nonnoxious stimuli (Touch, vibration, pressure, rapid movement) Large myelinated fibers activated by low-intensity stimuli
119
What are A δ fibers
Responsible for sensation of physiologic pain, fast pain or ‘first pain’ -Sharp, localized, transient Small receptive fields and high-threshold Thermal and mechanical input Small myelinated fibers, rapidly conducting
120
What are C fibers
Responsible for slow pathologic pain (Poorly localized, dull/aching or burning sensation) Polymodal (Activated by thermal, mechanical and chemical stimuli) Most of the cutaneous nociceptic innervation -Also found extensively in the muscles and viscera Large receptive field, slow conduction (Non-myelinated)
121
Where do sensory fibers synapse for modulcaton
dorsal horn of spinal cord
122
What molecules inhibits transmission of nociceptive stimuli
GABA, glycine, endogenous opioid peptides (Encephalin and endorphins) inhibits transmission of nociceptive stimuli
123
What are three principal pathways of modulation
1. local interneurons (excitatory and inhibitory) 2. neurons of segmental spinal reflexes 3. Neurons that projects to supraspinal structures -wide dynamic range (WDR) neurons, nociceptive specific neurons
124
What is the principal excitatory synaptic neurotransmitter (spinal cord and brain)? what are the receptors
glutamate and tachykinin
125
What is glutamate's receptor
NMDA, ampa, kainite Intense stimulation required to overcome Mg2+-mediated receptor blockade- Pain remains after stimulus has disappeared
126
Where is tachykinin released, and what does it mediate
c fibers, mediates pathologic pain
127
What three area is Central Integration
1. Brain stem (Medulla) and midbrain (Periaqueductal grey matter) 2. Hypothalamus 3. Cortex
128
What three actions does brain stem and midbrain do in central integration
Cardiorespiratory center alert responses Motor and emotional responses Alertness mechanisms (Fight-or-flight response)
129
What does hypothalamus do in central integration
Control of the autonomous nervous system response Hormone release for stress control
130
What does cortex in central integration
Pain perception (Quality, location, intensity and duration) Generation of complex emotional response
131
What causes peripheral sensitization
1. Tissue inflammation 2. Allodynia 3. Hyperalesia
132
How does tissue inflammation cause peripheral sensitization
Release of chemical ligands (H+, K+, ATP, proteases, COX-2, serotonin, histamine, chemokins and cytokines) Lowers threshold of activation for A-δ and C-fiber Recruits silent nociceptors
133
How does central sensitization "wind up"occur
NMDA receptor dishinibition and glial cell activation
134
How does nmda receptor dishinibition occur
Caused by repeated depolarization of the dorsal horn neurons NMDA stimulation leads to intracellular Ca2+ mobilization → Increased glutamate responsiveness ↑ Dorsal horn neuron excitability ↓ Spinal cord neuron inhibition
135
How does glial cell activation occur
Proinflammatory mediator production after nerve trauma Role in reduction of opioid efficacy
136
Three reasons to control pain
1. sympathetic tone increase 2. Counterregulatory hormone and RAAS activation 3. Behavioral changes
137
What does sympathetic tone increase do in pain
Proinflammatory mediator production after nerve trauma Role in reduction of opioid efficacy
138
What doe counter regulatory hormone and RAAS activation do in pain control
Cortisol, glucagon, ADH, growth hormone and IL-1 secretion, inhibition of insulin release Catabolic state -Hyperglycemia, proteolysis, lipolysis, sodium and water retention, decreased GFR, Immunosuppression, decreased wound healing
139
Which analgesics medications inhibit perception?
Anesthetics Opiods alpha 2 agonists benzodiazepines Phenothiozines
140
Which analgesics medications inhibit modulation?
Local anesthetics opioids alpha 2 agonists tricyclic antidepressants cholinesterase inhibitors NMDA antagonsits NSAIDS Anticonvulsants
141
Which analgesics medications inhibit transmission
Local anesthetics alpha 2 agonists
142
Which analgesics medications inhibit transduction
local anesthetics opiods NSAIDS Corticosteroids
143
When to use local blocks?
Enhance analgesia, lead to less use of systemic agents, decrease pain and wind up pain when used preemptively
144
What are 6 types of loco-regional anesthesia
1. Topical or surface 2. Infiltrative 3. Regional 4. Neuraxial 5. Intraarticular 6. IV regional
145
What is an epidural? vs spinal?
Administration of drugs into epidural (extra-dural) space. Spinal = subarachnoid space
146
What is the site of action for epidural
the nerve roots as they leave the spinal cord and travel out from the intervertebral foramina
147
Describe how to perform an epidural
1. Patient placed in sternal recumbence 2. Clip an area a tthe lumbosacral junction. 3. Aseptically prepare the skin 4. After washing hands and while donning sterile gloves palpate the wings of the ilium with your thumb and middle finger. Using index finger palpate the spinous process of 7th lumbar vertebra 5. Slide the index finger caudally down spinous process until LS space is palpable between L7 and S1 6. Keeping index finger in place insert a 20-22 gauage, 1.5 to 2.0 inch spinal needle perpendicular to the skin on midline 7. Advance needle to through ligamentum flavum usually a "pop" can be felt 9. remove stylet and confirm placement with hanging drop "fill hub of needle with saline and fluid in needle should rop into epidural space" 10. observe needle for blood 11. slowly inject local anesthetic of choice , should be no resistance 12. remove needle
148
What are three layers for epidural
Skin -Fascia- ligamentum flavum
149
What are contraindications for epidural
1. Infection at the site (wounds/contamination) 2. Coagulopathy 3. Hypotension/hypovolemia 4. Trauma in the region of injection 5. CNS disease/increased ICP
150