Exam 3 Flashcards
(125 cards)
1
Q
Anesthesia is a balance between ____ and ____ + ____
A
- surgical stimulation
2. drug induced depression + physiological disturbances
2
Q
Movement during anesthesia
A
- gross spontaneous movements (too light)
2. reflex movement in response to surgery (not necessarily because they are too light)
3
Q
Anesthetic Depth (6 things w/ eyes)
A
- globe position
- pupil size
- nystagmus
- lacrimation
- palpebral reflex
- corneal reflex
4
Q
Anesthetic depth (globe position)
A
Central (light) –> ventromedial (good) –> central (too deep)
5
Q
Anesthetic Depth (palpebral aperture size)
A
- increases with increasing depth
6
Q
Anesthetic depth (pupil size)
A
- highly variable
- dilated @ very deep states
7
Q
Anesthetic Depth (palpebral reflex)
A
- blink in response to touching the eyelids
- good depth = loss of reflex
8
Q
Anesthetic depth (corneal reflex)
A
- touch cornea and animal should blink
- loss of this = animal close to death
9
Q
Anesthetic Depth (jaw tone)
A
- resistance to manual jaw opening
- jaw done decreases as depth increases
- ketamine = always strong jaw tone
10
Q
Dissociative Anesthetic Drugs (depth signs)
A
- eye central
- retain palpebral
- too light: blinking, eyes closed, tearing, rapid nystagmus, spont. movement
11
Q
Non-signs of anesthetic depth
A
- flaring of nasal alae
- slight muzzle movement
- focal muscle twitching/ fasciculations seen w/ propofol, ketamine
12
Q
What three categories to monitor during anesthesia?
A
- Cardiovascular
- Respiratory
- Temperature
13
Q
What are the 3 H’s of anesthesia?
A
- Hypotension
- Hypoventilation
- Hypothermia
14
Q
Most anesthestics are ______ + _____ (cardiovasc)
A
- neg. inotropes and vasodilators
15
Q
Why might alpha-2’s cause cyanosis?
A
- alpha-2’s cause peripheral vasoconstriction that decreases blood flow in the periphery –> increased oxygen unloading
16
Q
Evaluation of hypotension?
A
MAP < 70mmHg
SBP < 90mmHg
17
Q
How to set up doppler?
A
cuff size = 40% limb circumference
18
Q
normal PaCO2 levels?
A
40+-5mmHg
19
Q
T/F: Patients with elevated intracranial pressure are particularly susceptible to elevated CO2 levels
A
T
20
Q
Effects of hypothermia
A
- decreased anesthetic requirements
- increased rate of complications (hem, bradycardia, infection rate)
- slows recovery
21
Q
Large Animal Complications
A
3H’s + handling and hypoxemia
22
Q
Ruminant Complications
A
Regurgitation (fasting)
Aspiration (keep sternal)
Bloat (fasting)
23
Q
The Recovery Period (SA and LA)
A
SA - 1/2 of all perianesthetic deaths post-op
LA - 1/3 of anesthesia related deaths
24
Q
Nursing Care pre-recovery
A
- empty bladder
- clean/ dress/ protect wounds
- position animal comfortably
25
What determines speed of recovery?
- drugs used (inhalants vs injectables)
- species (smaller are faster)
- Body temp (hypothermia slows recovery
26
Monitoring and Support during recovery
- heat support
- general observation
- supplemental O2
- CV support may be necessary
27
Should you sedate equines during anesthetic recovery?
probably,
- alpha-2's cause analgesia, fast onset, ataxia
- acepromazine is slow onset, non-analgesic
28
Why prevent bleeding in surgery (3 things)
1. maintain visibility
2. maintain perfusion
3. avoid transfusion
29
How to prevent bleeding in surgery
1. knowledge of anatomy
2. gentle tissue handling
3. familiarity w/ hemostatic techniques
30
Hemostatic Methods
1. blood flow reduction (pressure, forceps)
2. Vessel Ligation
3. Energy devices
4. topical agents
31
Hemostatic Methods (skin)
1. pressure
2. forceps
3. electro and laser
4. clips for deeper vessels
Generally, skin vessels are small and do not require ligation
32
Hemostatic Methods (SQ tissue and muscle)
1. pressure
2. forceps
3. clips or sutures
4. electro
5. vessel sealing device
33
Hemostatic Methods (Larger vessels and pedicles)
1. pressure and forceps (good to help buy time)
2. clips or sutures
3. vessel sealing devices
34
Hemostatic Methods (Parenchymal Organs)
1. pressure
2. gelatin sponges, oxidized cellulose
3. organ removal
small bleeds = pressure (anything more will increase bleeding)
35
Hemostatic Failure (sources)
- suture or clip fails
- inappropriate method of hemostasis used
- iatrogenic damage (rough handling of tissues)
36
How to identify hemostatic failure?
- blood pooling
- blood clots
- visual inspection of pedicles, divided vessels
37
Benefits of placing a drain?
- evacuate foreign material, necrotic tissue, bacteria and inflammatory mediators
- remove serum and blood
- relieve pressure
- reduce dead space
38
Indications of Open Passive Drain?
Therapeutic: abscess; wound not in thoracic or abd
Prophylactic: minimize dead space after dermal or SQ benign mass removal
39
Open Passive Drain (advantages)
- inexpensive
- simple to place and remove
- effective drainage of SQ pockets
- fit into small tisue pockets
- can be maintained at home
40
Open Passive drain (disadvantages)
- air and env. contamination
- not for thoracic and abd cavities
- external bandage dressing and fluid collection must be done regularly
- wound exudate can damage skin
- dif. to quantify or sterile sample fluid
- must be positioned well
41
Indications of Closed suction drain
Therapeutic: wounds and abscesses; peritonitis; pneumothorax; areas where gravity not helpful
Prophylactic: large areas of SQ dead space; surgeries in thoracic cavity; major reconstructive of GI, urogential, biliary tracts
42
Closed Suction Drain (advantages)
- decreased risk of ascending inf.
- effective drainage of fluid and air
- active suctions brings tissue layers in contact
- quantify draining material
- obtain sterile samples
43
Closed Suction Drain (disadvantages)
- more expensive
- must maintain closed, sterile system
- must reapply suction and empty grenade
- drains often too large for small vet pockets
44
T/F: oxidative stress results from an increase in ROS and decrease in antioxidants
T
45
Exogenous sources of ROS
- UV light
- ionizing radiation
- smoking/ air pollution
46
Endogenous sources of ROS
- mitochondria and NADPH oxidase
- 5-lipoxygenase
- xanthine oxidase
- NO synthase
47
ROS attack on lipids mech
- toxic "chain reaction" that kinks tail structure of phospholipids causing disordered packing and loss of cell structure
48
Anti-oxidant defense mechanisms
1. Enzymes
2. Proteins
3. Low-molecular weight substances (glutathionine)
4. Keap1-Nrf2 pathway
49
T/F: in order to prevent oxidant damage against lipids, you only need to have one of the many antioxidants
F: you need to have the entire list of antioxidants in order to prevent lipid damage
50
Keap1-Nrf2 pathways
- oxidant stress mobilizes the Nrf2 antioxidant response that activates transcription of many antioxidant genes
51
Glutathionine (moa)
fxs by reducing lipid peroxidases to less-toxic alcohols; also reduces Vit C
52
White Muscle Disease
- dietary deficiency in selenium or Vit. E
| - degenerative muscle disease in large animals
53
Heinz Body Anemia ( in cats)
- Hb is highly susceptible to oxidation damage due to larger numbers of -SH groups in cats than others
- -SH oxidation causes Hb to precipitate, distort RBC, and lysis
54
Red Maple Ingestion (horses)
- methemoglobin and heinz body anemia
55
Ischemia/ Reperfusion (moa of damage)
- low [O2] initially
- reperfusion causes oxidative burst that produces large number of ROS quickly
- paired immune response (activated PMN, TNF, IL1,6,8,12)
- tissue damaged in vascularized tissues
56
T/F: during reperfusion, you should have animals on supplemental O2 to make sure the tissues all get O2 as quickly as possible
F: this will cause increased damage
57
T/F: ROS can damage Proteins, DNA, and Lipids (membranes)
T
58
Antioxidant Defense Enzymes (2 of them)
1. Superoxide Dismutase
| 2. Catalase
59
What is the Fenton Reaction
Breakdown of H2O2 into OH* (ROS)
60
Organ Sensitivity to I/R
1. Brain
2. Heart
3. Kidneys
4. Intestines
5. Skeletal Muscle
61
Therapies for I/R
1. Enzymatic antioxidants (superoxide dismutase)
2. Dietary antioxidants (Vit. E, N-acetyl cysteine, melatonin)
3. Xanthine Oxidase inhibitors
62
What are the 6 types of shock?
1. Hypovolemic
2. Cardiogenic
3. Metabolic
4. Hypoxic
5. Distributive
6. Obstructive
63
What is the most common form of shock?
Hypovolemic
64
Clinical signs of hypovolemic shock?
- Decreased perfusion parameters (low volume)
- Hypotension
- Decreased urine volume
65
Oxygen Extraction Ratio (OER)
(SaO2 - SvO2)/ SaO2
looks for offloading problems
66
Distributive Shock
- inappropriate vasodilation --> septic shock, anaphylactic shock, neurogenic
67
Cardiogenic Shock (3 types and clinical signs)
1. Systolic Dysfunction (dec. contractility)
2. Diastolic dysfunction (inadequate fill)
3. Dysrrhymthias (v. fib or something)
- hypoperfusion, hypotension, ECG abn, murmurs
68
Obstructive Shock
- extracardiac mechanical obstruction to cardiac output
| - pulmonary thromboembolism
69
Hypoxic Shock
- blood volume and blood flow may be n
| - deficiency in O2 leads to shock
70
5 causes of Hypoxic shock
1. low PiO2
2. V/Q mismatch
3. diffusion impairment
4. hypoventilation
5. R-->L shunt
71
Metabolic Shock
- impaired O2 utilizaiton (either mitochondrial problem or decreased substrate, severe hypglycemia)
72
How to treat hypovolemic shock?
IV fluids
73
How to treat Distributive shock?
Septic: antimicrobials
Anaphylactic: epi, antihistamines
Neurogenic: treat neuro dz
74
How to treat Cardiogenic shock?
systolic: inotropes
diastolic:
Tachyarrhymthias =: SVT, VT
75
How to treat obstructive Shock?
relieve obstruction
76
How to treat hypoxic shock?
O2 supplementation, mech. ventilation
77
Fluids TROL?
Types, Rates, Objectives, Limits
78
Hypertonic crystalloids benefits?
- will pull water from interstitial space for large animals
| - increased contractility
79
2 approaches to shock fluid rates
1. deficit volumes
| 2. fluid challenge (give bolus then reassess)
80
What are the ABCs of CPR?
Airway
Breathing
Compressions
81
Difference between Cardiac Pump vs Thoracic Pump?
Cardiac Pump --> direct compression of the heart
| Thoracic Pump --> changing intrathoracic pressure to move blood through the heart
82
When to use a direct cardiac massage
- already in the abdominal or thoracic cavity
| - failure of n compression techniques
83
How to check efficacy of compressions?
- pulse palpation (not v good)
- doppler flow probe (not v good)
- End Tidal CO2 (best way to check)
84
What are the DEFs of CPR
Drugs
ECG
Fluid Therapy
85
What drugs to use in CPR?
We use vasopressors (mainly Epinephrine and ADH)
- Epi has B1 activity that can be bad upon resuscitation
- ADH is just expensive
86
ECG in CPR?
- need to stop compressions to evaluate
| - use for V. fibrillation vs asystole vs Pulseless Electrical Activity
87
Fluid Therapy in CPR?
- good if hypovolemic
- bad if not hypovolemic as it increases work that the heart has to do
- ER patient give 1/2 to full dose; ICU patient only flush drugs
88
Post-Cardiac Arrest Care
- most that resuscitate don't survive long enough to leave the hospital
- don't oxygenate either way because bad
89
Define: ostium
opening into a tube
90
Define: perforation
a hole or opening into an organ
91
Define: Atresia
abn closure or absence of an orifice or passage
92
Define: -otomy
to cut or make an incision into
93
Define: -ostomy
surgically creating a new opening
94
Define: -ectomy
surgical removal
95
Define: -pexy
surgical fixation
96
Why use contrast studies for hollow organs
- look for leakage
- look for obstructions/ strictures
- assess diameter/ size
97
Basic Surgery Principles ( Gastrotomy )
- stay sutures
- laparotomy sponges
- intraperitoneal irrigation
- clean/ dirty instrumentation
98
Basic Surgery Principles (Intestinal Surgery)
- delicate tissue handling
- respect the blood supply
- protect against leakage of int. contents
99
Basic Surgery Principles ( Cystotomy)
- stay sutures
- laparotomy sponges
- prevent urine leakage
100
T/F: You should consider complications during and after surgeries and for those impacting all surgeries
T
101
Myocardial perfusion pressure equation
(aortic diastolic pressure) - (R. Atrial pressure)
102
the volatility of a liquid anesthetic in a carrier gas is
saturated vaport pressure
103
Alpha 2 agonist that is 10x more potent in cattle than horses
Xylazine
104
hypoventilation
40+-5 mmHg
105
best non-invasive way of measuring PaO2 during anesthetic recovery
pulse oximeter
106
minimum fresh gas flow rate for bain circuit is...
200mL/kg*min or 500mL/min
107
What drug would you give that would increase heart rate when paired w/ opioid
Atropine, glycopyrrylate
108
The two 'shockable' ecg waveforms
pulseless ventricular tachycardia and v. fibrillation
109
This fluid type is anti-inflammatory and a positive inotrope
hypertonic saline
110
way to check for dehydration
skin turgor, mucous membranes, tear film
111
recommended compression rate and duration of compressions per cycle
120bpm for 2 minutes
112
sedation in adult sheep, goats, but not cats and dogs
diazepam and midazolam
113
3H's
hypotension, hypothermia, hypoventilation
114
LRS admin during n anesthesia (rates)
3-5mL/kg/hour
115
inhaled agent with lowest MAC
isoflurane
116
6 perfusion parameters
```
mucous membrane color
CRT
mentation
heart rate
pulse quality
extremity temp
```
117
Hepatic clearance relies on (3 things)
1. blood flow
2. intrinsic clearance
3. protein binding
118
Are high ER (extraction ratio) drugs more or less dependent on blood flow than low ER drugs?
more
119
decreased hepatic blood flow effect on abs. and clearance
increased abs
| decreased clearance
120
decreased phase 1,2 enzymes on clearance
decreased clearance
121
decreased albumin on distribution and clearance
increased distribution
| variable clearance
122
Total renal excretion = _____ + ______ - _______
rate of filtration + secretion - reabsorption
123
in an animal with renal disease what should happen to dose and dose intervale
dose should decrease
| dose interval should increase
124
GI dz primarily affects _____
absorption
125
Cardiac dz problems
redistribution of blood flow (all phases)
retention of Na/ H2O
decreased hepatic blood flow
