Anesthesia Flashcards
What diameter of ET tubes is typically used in cats?
3-4.5 mm
What diameter of ET tube is used in dogs?
1-2 kg starts at a 5 and then goes up 1-2 mm for every 2 kg of dog
How do you measure the length of an ET tube?
Tip of nose to thoracic inlet
What could an inappropriate length of ET tube cause?
Inappropriate length could result in hypoxia and hypoventilation
How do you check ET tube placement?
- Observe condensation in tube
- Palpate neck area
- Observe air movement
- Auscultate lung sounds
- Observe capnograph
How do you check for leaks?
Close pop off valve
Put thumb over tube
Fill reservoir bag with air
Apply positive pressure to reservoir bag and observe manometer up to 30 cm H2O
What patients should you use lidocaine on and why?
Cats and rabbits to prevent laryngospasm
What do feline tubes sometimes require that dogs dont?
Stylet because of the small size
When can you extubate?
When gag reflex is intact and patient is swallowing. Cats you can also monitor for ear flicks.
What is the gas supply?
compressed gas cylinder or central supply line
What is the check valve?
Ensures one way flow of O2 at beginning of anesthesia machine
What is the Pressure reducing valve?
Reduces pressure from tank to approximately 50 psi
What is the pressure gauge?
Indicates cylinder pressure when valve is open
What is the flow meter?
Measures rate of gas flow in L/min and further reduces pressure to approximately 15 psi
What does the vaporizer do?
Converts liquid anesthetic to gasWh
What are the types of breathing systems?
F circuit or bain system
What do the unidirectional valves do?
Ensure a unidirectional flow of gas in the breathing system. 1 for inspiration and 1 for expiration
What is the reservoir bag for?
Used to manually ventilate patient
What does the pop off valve do?
Close for leak test or to fill the reservoir bag
What does the CO2 absorber do?
Soda lime canister removes CO2 from expired gases
What is the common gas outlet?
Where mix of gases exits machine into breathing system
What is the oxygen flush valve?
Bypasses vaporizer to deliver pure oxygen
What is the pressure manometer?
Measures the pressure in the breathing system
What is the scavenging system?
Collects waste gas and delivers to activated charcoal or outside
What is the negative pressure relief valve?
Safety valve that opens to allow negative pressure to escape
What is the scavenger interface?
Opens to release air if scavenging system fails
What is the circuit alarm?
Sounds if pressure level is greater than 15 cm H2O
How do you calculate the volume of cylinders?
Multiply the available cylinder pressure in psi by conversion factor
What is the standard pressure in a full O2 cylinder?
2200 psi
How do you calculate the volume of a O2 cylinder?
Multiply psi by 0.3
When should you change an O2 cylinder
When pressure drops below 100
What is vapor pressure?
Pressure exerted by gas and varies by temperature
What is an additional measure on the anesthesia machine that can be used to monitor breath?
Unidirectional valves
What size patient for a 0.5 L reservoir bag?
0-6 kg
What size patient for a 1 L reservoir bag?
6-16 kg
What size patient for a 2 L bag?
16-35 kg
What size patient for a 3 L bag?
greater than 35 kg
What color do granules in soda lime container change?
blue or purple
When should you never use the oxygen flush valve?
bain system on a small patient
What should the manometer not exceed when providing assisted ventilation?
15-20 but in some dogs up to 30
What should the rate and pressure be on an anesthetic ventilator?
1:1 inspiration/expiration and no greater than 30 cm H2O
What should you do if a canine is spontaneously breathing?
ensure the pop off valve is closed
What is bypassed on a non-rebreathing system?
unidirectional valves, pop off valve, and soda lime canister
What systems are monitored with anesthetic monitoring?
- CNS
- Cardiovascular
- Ventilation
- Oxygenation
- Fluids
- Temperature
What do you use to measure CNS in anesthetic monitoring?
- Eye Position
- Palpebral Reflex
- Corneal Reflex
- Pupil size
- Pedal Reflex
- Jaw Tone
What do you use to measure Cardiovascular in anesthetic monitoring?
- HR
- Pulse Rate
- Rhythm
- BP
- CRT
What do you use to measure ventilation in anesthetic monitoring?
- Rate
- Tidal Volume
- Oxygenation
- Capnography
- Blood Gas Analysis
What is the normal eye position?
- Central when too light or too deep
- Rotate ventromedially during Stage 3, Plane 2
What is the normal palpebral reflex?
Disappears as patient gets deeper
What is the normal corneal reflex?
Should be present but will disappear with overdose
What is normal pupil size?
Constricted in light surgical plane. Dilates in non-surgical or deep surgical plane
What is normal pedal reflex?
Disappears with Surgical plane
What is normal jaw tone?
Disappears in light surgical plane
What is normal anesthetic HR?
Dogs 70-140 BPM
Cats 110-160 BPM
What should be noted with Heart rhythm in anesthetic monitoring?
Note arrythmias
What should be noted with pulse in anesthetic monitoring?
Pulse should match HR
What is the normal blood pressure in anesthesia monitoring?
Systolic 100-160 mmHG
Mean 80-120 mmHG
Diastolic 600-100 mmHG
What is normal CRT?
less than 2 seconds
What is the normal respiratory rate?
8-20 BPM
What is the normal tidal volume?
10-15 ml/kg
What is the normal oxygenation?
greater than 98 %
What is the normal capnography?
35-44 mmHg
How do you measure eye reflexes?
touch or tap
How do you measure eye position and pupil size?
Visualize
How do you measure jaw tone?
open mouth
How do you measure heart rate, pulse, and rhythm?
Palpation
Stethoscope
ECG
Doppler
How do you measure BP?
Palpate
MM Color
Indirect Monitor: Doppler or Oscillometric
Direct Monitor: Arterial line
How do you measure RR?
Visualize breaths on patient or anesthesia machine
Stethoscope
How do you measure respiratory depth?
Capnography
What causes abnormal CNS?
Depth of sx plane
Some drugs
What causes bradycardia? (10)
- Drug effect
- Anesthetic depth
- End stage hypoxia
- Hypertension
- Vagal Nerve Stimulation
- Hypothermia
- Hyperkalemia
- Myocardial Ischemia
- Hypoxemia
- Fluid Overload
What causes Tachycardia (9)?
- Pain
- Hypoxemia
- Hypercarbia
- Ischemia
- Anaphylaxis
- Anemia
- Hypovolemia
- Drug Effects
- Fever
What causes hypotension?
- Hypovolemia
- Shock
- Drug Effect
- Depth of Anesthesia
What causes hypertension?
- Pain
- Hypercarbia
- Fever
- Drug Effect
What causes decreased CRT?
Hypovolemia
What causes tachypnea (7)?
- Anesthetic Depth
- Hypoxemia
- Hypercapnea
- Hyperthermia
- Post Op Pain
- Drug Induction
- Individual Variation
What causes hypercapnea?
- Excessive depth of anesthesia
- Airway obstruction
- Thoracic or Abdominal Restrictive dz
- pulmonary dz
- Dead space breathing
What causes Hypoxemia?
- O2 flow too low
- Breathing room air
- Venous admixture
What causes hypothermia?
Thermoregulation fails or environmental losses
What causes hyperthermia?
- Excessive heat application
- Drug Interaction
- Genetic defect such as malignant hyperthermia
How many stages of anesthesia are there?
4
What is the first stage of anesthesia?
Induction phase
What are the signs of stage 1?
- Sensations become dull
- Loss of pain
- Normal pupils
- Increased BP
- Increased RR
- Vomiting
- Voluntary movement