Practical Review Flashcards
1
Q
Tachypnea
A
Abnormally rapid breathing
2
Q
Dyspnea
A
Difficult or labored breathing
3
Q
Hypoxemia
A
Low concentration of oxygen in the blood
4
Q
Hypercapnia
A
High levels of carbon dioxide in the blood
5
Q
Hyperthermia
A
Having a higher than normal body temperature
6
Q
Hypothermia
A
Having a lower than normal body temperature
7
Q
Apnea
A
Stop breathing
8
Q
What are the premedication protocol for surgery at pierce college?
A
Dogs: Hydromorphone (given SQ)
Cats: Dexmedetomidine & Buprenorphine
9
Q
What are common pre anesthetic agents used on dogs?
A
- Hydromorphone
- Butorphanol & Midazolam
10
Q
What are common pre anesthestic agents used on cats?
A
- Dexmedetomidine & Buprenorphine
11
Q
What are common induction agents used on cats?
A
- Midazolam & Ketamine
- Propofol
12
Q
What are common induction agents used on dogs?
A
- Midazolam & Ketamine
- Propofol
13
Q
Hydromorphone drug class?
A
Pure Agonists Opioid
14
Q
What is the duration of hydromorphone?
A
4 hours
15
Q
Why is hydromorphone a good pre anesthestic agent?
A
- Depresses the central nervous system
- Great Analgesia *Somatic & Visceral pain control
- Great Sedation
- Higher potency opioid which allows for lower vaporizer needs
16
Q
What are adverse effects to suspect with Hydromorphone?
A
- Decreased heart rate (low 60’s)
- Decreased respiratory rate
- Increased GI secretions (vomiting & hydroshits)
- Panting (Hydropant)
- Mydriasis (Dilated pupils)
- Increased salivary secretions
17
Q
What is the reversal agent for Hydromorphone if there is one?
A
Naloxone
18
Q
Dexmedetomidine drug class?
A
Alpha 2 Agonist
19
Q
Dexmedetomidine is a good pre anesthestic agent because?
A
- Good Sedation
- Muscle relaxation
- Good Analgesia *Somatic & Visceral
- Central nervous system depression
20
Q
What are common adverse effects when using Dexmedetomidine as a Preanesthetic?
A
- Decreased heart rate
- Decreased respiratory rate
- Decreased blood pressure
- GI Upset/ Vomiting / Nausea
- Reaction to loud noises
21
Q
Dexmedetomidine is commonly used in conjunction with what drug for a Preanesthetic agent
A
Buprenorphine
*Common pre med for cat surgeries & dentals
22
Q
Buprenorphine is commonly used in conjunction with what drug as a pre anesthestic agent?
A
Dexmedetomidine
*Common pre med for cat spays & dentals
23
Q
Buprenorphine drug class
A
Opioid
24
Q
Why is Buprenorphine a good pre anesthestic agent?
A
- Good analgesia *Somatic & Visceral
- Depression of the central nervous system
- Good Sedation
25
What is the reversal agent for Dexmedetomidine if there is one?
AntiSedan (Atipamezole)
*Because Dex is an Alpha 2 Agonist
26
What are some adverse effects expected to see when using Buprenorphine as a Preanesthetic agent?
- Decreased heart rate
- Decresed respiratory rate
- GI Upset
- Mydriasis (Dilated pupil)
27
What is the reversal agent for Buprenorphine if there is one?
Naloxone
*Because its an opioid
28
What are common induction agents used for cats?
- Midazolam & Ketamine
- Propofol
29
What are common induction agent protocols used for dog spays/neuters & dentals?
- Midazolam & Ketamine
- Propofol
30
What are common induction agent protocols used for dog spays/neuters & dentals?
- Midazolam & Ketamine
- Propofol
31
Propofol drug class?
Ultra short acting non-barbiturate
32
Propofol duration of action?
2-5 minutes
*Highly protein bound
33
When giving Propofol you must remember?
- Give slow over 50 seconds
- Titrate dose to effect *25% - 50% - 75%
- Dose can be repeated every 3-5 minutes if intubation is difficult
34
Why is propofol a good induction agent?
- CNS depression
- Muscle relaxation
35
What are some adverse effects that are common to see when inducing with Propofol?
- Transient excitement
- Decreased heart rate (Bradycardia)
- Decrease respiratory rate
- Decrease blood pressure (Hypotension)
36
Midazolam drug class
Benzodiazepine
37
Midazolam drug class
Benzodiazepine
38
Midazolam is commonly used in conjunction with what drug in a pre anesthestic drug protocol?
Ketamine
39
Ketamine is commonly used in conjunction with what drug in a pre anesthetic drug protocol?
Midazolam
40
Midazolam drug class
Benzodiazepine
41
Why is Midazolam a good pre anesthetic agent?
-Good sedation
-Muscle relaxation
-Eases induction & recovery
42
What is the reversal agent for Midazolam if there is one?
Flumazenil
43
Ketamine drug class?
Dissociative anesthetic
44
Ketamine adverse effects that are common when administering this induction agent?
- Induces catalepsy/cataleptic
- Muscle rigidity
- May precipitate seizures
- May increase salivary secretions
- Swallowing/Laryngeal reflex may persist
- No analgesia
- Increased heart rate
- Apneustic respiration
45
What are important notes when induces with ketamine?
- Can increase heart rate
- Induces catalepsy
- Must be combined w/ a benzodiazepine &/or alpha 2 agonists to allow for greater muscle relaxation
- Eye lubricant is very important due to catalepsy
46
Is there a reversal agent for ketamaine?
No
47
What post op pain medication is used after Ricotta’s spay surgery?
Carprofen (Rimadyl)
48
When is Carprofen to be given?
Immediately after extubating
49
What is the reversal agent for opioids?
Naloxone
50
What is the reversal agent for benzodiazepines?
Flumazenil
51
What is the reversal agent for Alpha 2 Agonist?
AntiSedan (Atipamezole) & Yohimbine
52
What are common anticholinergics used in veterinary medicine?
1. Atropine
2. Glycopyrrolate
53
Why are anticholinergics drugs used?
To counteract the parasympathetic nervous system.
-Treat bradycardia (raise heart rate)
-Prevent excessive salivation & respiratory secretions
-Can decrease GI motility
- Can cause mydriasis
54
What are common halogenated gasses used in vet med?
- Isoflurane
- Sevoflurane
55
What adverse effects are expected to see when using halogenated gasses?
- CNS depression
- Hypothermia
- Hypotension
- Good muscle relaxation
- Respiratory depression
- Decreased cardiac output
56
Is Isoflurane or Sevoflurane more potent?
Isoflurane is more potent than Sevoflurane
57
What is the maintance rate for Sevoflurane?
2.5 - 3.5 %
58
What is the induction rate for Sevoflurane?
4 - 5 %
59
What is the maintenance rate for Isoflurane?
1.5 - 2.5 %
60
What is the induction rate for Isoflurane?
3 - 4 %
61
Does Isoflurane or Sevoflurane have a higher blood gas partition?
Sevoflurane is at 0.68 & Isoflurane is at 1.46 therefore Isoflurane has a higher blood gas partition
62
What effects does blood gas partition have on the speed of induction, change in depth & recovery?
Agents like Sevoflurane and Isoflurane that have low blood partition coefficient allow for rapid induction, rapid response to changes in the vaporizer percentage, & relatively fast recovery allowing for the patient to wake up pretty quickly after the vaporizer is turned off
63
What stage is considered surgical anesthesia?
Stage III
64
What respiratory pattern should be seen in surgical anesthesia?
Smooth & regular breaths with both the thoracic & diaphragm should move in smooth motions
65
Stage III Surgical Anesthesia Vital Signs: Respiratory Rate
Normal: 12-20bpm
*Low as 8 in large active dogs
Alert: <8 & >20 bpm
66
Stage III Surgical Anesthesia Vital Signs: Heart Rate
Dogs:
Normal: 60-150bpm
Alert: <60 - >160bpm
Cats:
Normal: 120-180bpm
Alert: <100 - >200bpm
67
Stage III Surgical Anesthesia Vital Signs: ETCO2
Normal: 35-45 mmHg
Max: 55mmHg
68
ETCO2 >45mmHg indicates?
Hypoventilation
69
ETCO2 reading <35mmHg indicates?
Hyperventilation
70
Stage III Surgical Anesthesia Vital Signs: Temperature
Normal: 97-100 F
Alert: <97 & >103.5
71
Stage III Surgical Anesthesia Vital Signs: Blood Pressure
Average: 120/80
Normal: 110-160/50-100
Systolic: 110-160
Diastolic: 60-100
Alert: 80/40
72
Stage III Surgical Anesthesia Vital Signs: MAPS
Mean Arterial Blood Pressure
Normal: 60-90
Alert: <60
73
Stage III Surgical Anesthesia Vital Signs: SPO2
Pulse Oximeter
Normal: >95%
Alert: 90-94% Early Hypoxemia
*85-89% Therapy Required
74
How can you monitor blood pressure?
- Blood pressure cuff
- Pulse Palpation
- Mucus membrane color
- CRT
- Blood pressure Doppler
75
What reflexes should be present in stage III surgical anesthesia?
- Corneal reflex
- Moderate Muscle Tone
- Ventromedial eye position
- Midrange Pupil Size
76
What reflexes should be absent in stage III surgical anesthesia?
- Swallowing
- Palpebral
- Pedal
- No spontaneous movement
77
What are common causes of bradycardia?
- Excessive anesthetic depth
- Administration of drugs *Alpha 2 Agonists/Opioods
- Stimulation of vagal nerve
- Hypertension (high blood pressure)
- Hyperkalemia (high potassium in blood)
- Hypothermia (low body temperature)
- Hypoxia (Low oxygen in tissues)
78
What are common causes of tachycardia?
- Inadequate anesthetic depth
- Pain during surgical stimulation
- Blood Loss
- Hypoxemia &/or Hypercapnia
- Pre existing conditions
- Hyperthyroidism
- Hypotension
- Shock
- Congestive Heart Failure
- Administration of Drugs
- Anticholinergics
- Dissociative anesthestics
- Epinephrine & Dopamine
79
How do you go about correcting/treating bradycardia?
- Start by checking the patients CRT, pulse Oximeter, blood pressure & pulse strength & if they all appear normal that that means tissue perfusion may be adequate still
- Due to anesthetic depth than decrease the vaporizer setting
- If due to drug administration than using a reversal agent may be warranted
- Administering Atropine
80
How do you go about correcting/treating tachycardia?
- Increasing anesthetic vaporizer to increase anesthetic depth
- If due to painful stimulation an IV injection of an analgesic may be warranted
81
How to measure the heart rate during anesthesia?
- ECG w/ Monitor
- Pulse Rate on Monitor
- Esophageal Stethoscope
82
Why is it hard to hear the heartbeat at times during a surgical procedure?
- Anesthesia decreases the heart strength of contractions
- The heart will gravitate to the lower aspect of the thoracic cavity
83
What are common cause of hypotension? (Low blood pressure)
- Anesthetic Agents
-Acepromazine, Alpha 2 Agonists, Barbiturates, Propofol, Inhalant agents
- Excessive anesthetics depth
- Blood Loss
- Dehydration
- Cardiac arrhythmias
- Preexisiting heart disease
- Gastric distinction
84
How can you treat hypotension in an anesthetized animal?
- Reduce anesthetic depth if possible
- Fluid Bolus 10mg/kg for 15 minutes
- Crystalloid fluids
- ER Drugs (Norepinephrine, Dopamine & Dobutamine)
* Dobutamine raises blood pressure solely by increasing cardiac output
* Dopamine raises blood pressure via peripheral vasoconstriction
- Supply external heat source
85
How can we measure oxygen saturation?
Pulse Oximeter (SPO2)
86
What causes a low pulse oximetry reading?
-Reposition SPO2 reader as sometimes we can loose perfusion to an extremity especially a tongue
-Pre meds like alpha 2 agonists will cause vasoconstriction decreases SPO2 values
-Hypothermia
-Hypotension
-Blood loss
-Inadequate oxygen being delivered to the patient
-Empty oxygen tank
- Esophageal intubation
- oxygen flow rate to low
-Inadequate ventilation (lung disease)
-Inadequate circulation (heart disease/bradycardia)
87
Dyspnea
Indicates that the animal is unable to obtain sufficient oxygen or adequately remove CO2
88
Cyanosis
Indicates that tissue oxygenation is inadequate
89
How do you treat a truly low SPO2/Cyanosis or Dyspnea?
-First ensure oxygen is being delivered to the patient
-Turn the vaporizer off & the animal should bed bagged with 100% oxygen
-Administration of IV fluids
-Administration of ER drugs like Doxapram
90
What is a good rule of thumb when it comes to the respiratory rate & heart rate under anesthesia?
- Heart rate & Respiratory rate decrease as anesthetic depth increases
- Heart rate & respiratory rate increase as anesthetic depth decreases and/or due to surgical stimulation and/or painful stimulation
91
What is a capnograph?
ETCO2
92
What does a capnograph measure?
- Measures the amount of CO2 in the air that is breathed in and out by the patient
- Abnormal CO2 levels are most commonly a result of changes in ventilation (hyperventilation, hypoventilation, & apnea) or equipment problems
93
What cause hyperventilation/Tachypnea?
-Inadequate anesthetic depth (Surgical stimulation or pain)
-Lack of oxygen supply (Hypoxemia/Hypercapnia)
-Hyperthermia
94
How do we treat hyperventilation or Tachypnea?
-Assess anesthetic depth
-Check CO2 granules
- Give breaths 6-8 per minute
95
What causes Hypoventilation?
-Failure of oxygen delivery (ventilation)
-AIrway blockage (mucus plugging the ET tube)
-Respiratory disease
-Excessive pressure on the chest cavity / diaphragm
-Being tilted on the table
-Excessive anesthetic depth
96
How do you treat Hypoventilation?
-Assess anesthetic depth
-Manual ventilation
-Ventilator
-Administer of ER drug: Doxapram
97
Will Hypoventilation cause the ETCO2 increase or decrease?
ETCO2 will increase
>45
98
Will hyperventilation cause the ETCO2 to increase or decrease?
The ETCO2 will decrease
<35 mmHg
99
What will cause abnormal ETCO2 readings?
- Detachment of endotracheal tube from the sensor
- Blocked endotracheal tube
- Apnea
- Closed pop off valve
- Exhausted CO2 absorbent granules
- Malfunctioning exhalation unidirectional valve
- A leaky cuff or partially kinked endotracheal tube
- Hypotension
- Hypothermia
100
Why does body temperature decrease under anesthesia?
- Body temperature should be monitored every 15-30 minutes except in surgery
- Anesthetics decrease the body temperature by depressing the hypothalamus, reducing muscular activity & slowing the metabolic rate.
- An anesthetized animal is incapable of generating heat by shivering or muscular activity
- The metabolic rate of an anesthetized animal is less than a conscious animal resulting in less heat generation
- For this reason hypothermia is a frequent & expected response to general anesthesia
- Some drugs cause peripheral vasodilation resulting in increased heat loss
- During surgery a body cavity & viscera is exposed to the room temperature
- Due to surgical prep like shaving, & surgical scrub
- Administration of room temperature IV fluids
- Temperature loss is greatest in the first 20 minutes
101
What can we do to prevent temperature loss?
- The use of external heat support like hot dog for surgery
- Warming the IV fluid
- Recovery: Bear Huggers, blankets, & hot dog
102
Are there any causes for hyperthermia?
- Excessive administration of external heat
- Drug induced reactions
- Opioids / Ketamine
- Cats especially w/ Opioids
- Ketamine excessive muscle activity
- Inability to dissipate heat
- Large dogs w/ thick coats under surgical drapes
- Using a rebreathing system at times can increase the temperature of the air being rebreathed
103
What are common causes for anesthetic emergencies?
1. Human Error
- Inadequate training
- Lack of familiarity with anesthetic machine or agents
- Failure to adequately prepare the patient
- Drug calculations or administration
- Fatigue/haste/inattention
2. Equipment related issues
- Closed pop off valve
- Empty or overfilled vaporizer
- Exhausted CO2 granules
- Plugged ET tube (Use 20 mL syringe & feeding tube & suck out the plug)
3. Adverse Effects of Anesthetic Agents
- Acepromazine poor to use in patients with low blood pressure
- Dexmedetomidine is not safe for use in patients with cardiovascular or respiratory disease
- In general Alpha 2 Agonists cause bradycardia, cardiac arrhythmias, vomiting, & respiratory depression
- Understanding the balance needed with balanced anesthesia
- pre med, induction & gas
4. Increased Patient Risk
- Neonates (6-12 weeks)
- Geriatric animals
- Brachycephalic animals
- Sighthounds
- Obese animals
- Cesarean delivery patients
- Emergency patients: shock, trauma, cardiopulmonary distress
104
Why do brachycephalic animals pose more challenges for the anesthetics
- These patients are at a higher risk due to their anatomic abnormalities that increase their susceptibility to airway obstruction
- Body Conformities related to the skull & upper airway
- Very small nasal openings
- Elongated soft palate
- Everted Laryngeal saccules
- Small diameter trachea
- Thick fleshy tissue on the laryngopharynx hampering breathing
- Collapsing Trachea / Choosing the right anesthetic agents
- Opioids, sedatives, & tranquilizers depress respiration & reduce muscle tone in the pharyngeal & laryngeal area which can collapse the tissue surrounding the airway causing respiratory distress
- Postoperative swelling & hemorrhage may occur increasing the risk of respiratory difficulty
- Abnormally high parasympathetic tone which may cause bradycardia
- Minimizing Risks During Anesthesia:
- Preoxygenate patients 5 minutes before anesthetic induction
- Administer oxygen through facemask with light restraint
- Choose rapid induction agents that are rapidly metabolized
- Propofol, Alfaxalone, Ketamine-Midazolam/Diazepam
- Use laryngoscope for intubation to allow for visualization of the laryngeal opening through the large amounts of redundant tissue in the pharynx
- Using a smaller endotracheal tube than expected for the size/weight of the animal
105
How do we minimize risk that brachycephalic animals pose?
- Closely monitored
- Endotracheal tube should be left in place as long as possible
- Oxygen should be delivered
- After extubation the animals head & neck should be extended & observed closely for dyspnea & cyanosis
- It is recommended to have supplies ready for reintubation including induction agent if necessary
- Excitement & stress should be minimized
106
Why would an animal not stay under anesthesia?
- Inadequate vaporizer setting
- Inadequately filled anesthetic vaporizer
- Blocked, misplaced, disconnected endotracheal tube
- Endotracheal tube that is to small
- Inadequately cuffed endotracheal tube
- Apnea or inadequate tidal volume
- Commonly seen after intubation when using Propofol / Alfaxalone
- Apnea may lead to arousal because the gas molecules are not able to fully saturate the lung
- Tidal volume will be inadequate when the patient is huffing (rapid, shallow breathing) due to insufficient anesthetic depth
- AbsentInadequate Oxygen Flow
- Malfunction with calibration of vaporizer *change machines
107
What signs would you see with an animal that is to deeply anesthetized?
- Respiratory rate of 6 bpm or fewer
- Shallow respirations or exaggerated respiratory movements
- Pale or cyanotic mucous membranes
- Capillary refill time greater than 2 seconds
- Bradycardia
- Weak pulse
- Systolic blood pressure less than 80 mmHg
- Cardiac arrhythmias
- Cold extremities
- Body temperature less than 95F
- Absent of reflexes including palpebral & - corneal reflexes
- Flaccid muscle tone
- Dilated pupils ( of pupillary light reflex)
108
What could cause a cardiac arrest in an anesthetized patient?
- Respiratory arrest
- Drug Reactions
- Hypoxia of the heart muscle
- Disease conditions such as gastric dilatation-volvulus, & heart muscle trauma
- Anesthetic overdose
109
What drugs are commonly used if a patient arrests?
1. Epinephrine
- increases heart contractions
2. Vasopressin
- vasoconstrictor increasing blood pressure
3. Atropine
- prevent/treat bradycardia
4. Sodium Bicarbonate
- When CPA has lasted more than 10 minutes
110
Oxygen flow rate: Rebreathing system
3(weight in kg X 10)=mL/min
111
Oxygen flow rate for non rebreathing system
Weight in kg X 300 =mL/min
112
Fluid flow rate?
5mL/kg/hr
113
Fluid Bolus fluid rate?
10mL/kg for 15 minutes
114
When you first hook the patient up to the anesthesia machine after induction what should you do?
Hook the patient up to oxygen & turn it on 3x maintenance rate initially
