Respiratory&Temp Clinical Monitoring Flashcards
Describe what kind of etCO2 waveform this represent?
Normal!
What does each letter represent?
A-B = Baseline
B-C = Expiratory Upstroke
C-D = Expiratory Plateau
D = End- Tidal Concentration
D-E = Inspiration
Describe what kind of etCO2 waveform this represents
Something is hindering expiration
You have a loss of plateau, you have lost your C curve
What are some causes of this waveform of etCO2
-Bronchospasm / Asthma
-Bronchospasm/COPD
-Obstruction in the expiratory limb of breathing circuit
-Presence of foreign body in the upper airway
-Partially kinked or occluded artificial airway
Will normal capnography waveforms look different depending on the type of airway management?
yes!
ETT, LMA, Nasal Cannula, Spont.
Shape changes, but phases are universal.
How many phases of normal capnogram?
4
Describe the first phase of etCO2
The end of inspiration and the very beginning of expiration
What gas is being sampled in phase one of etCO2? What should it be?
Comes from anatomic dead space, baseline, should be around 0.
You shouldn’t be exhaling CO2 at the end of your inspiration.
Describe the second phase of etCO2
Measuring the expiratory upstroke, your active expiration
What gas is being sampled in phase 2 of capnography
Dead space and alveolar gas.
Deadspace is the air that is stagnant in your airway, not participating in gas exchange.
Describe the third phase of etCO2
records plataeu, should be nearly flat, records alveolar emptying of CO2.
LONGEST duration of measurement. etCO2 measured at the very end of the phase, just prior to phase 4
What phase does the etCO2 that we chart come from
3! very end of phase three
Describe the fourth phase of capnography
Rapid decrease in CO2 of sampled gas as a result of inspiration of O2. Should return close to 0.
When evaluating capnogram what things should you be evaluating
Respiratory Rate
Whether ventilation is spontaneous or mechanical
Value of etCO2
Shape of waveform
Presence of additional respiratory efforts
What about waveform will tell you the patient is rebreathing CO2
A waveform that fails to return to baseline during the first and fourth phase
Describe what kind of etCO2 waveform this represents
Cardiac Oscillations
Result of contraction of the heart and great vessels forcing gas in and out the lungs(?)
What patients are you most likely to see this waveform and why?
Pediatrics, due to the relative size of the heart to the thorax
Describe what kind of etCO2 waveform this is
Curare Cleft, indicative of spontaneous respiratory effort
When you see this capnography waveform, what might you need to do?
Deepen anesthetic, pt initiating spontaneous breaths
If you have a flat end-tidal waveform, what can this indicate?
- You tubed the goose, ya silly goose.
- The circuit got disconnected
- Not ventilating (did you turn the ventilator on?)
ASA standards state etCO2 monitoring should be used when propofol is administered during which specific type of procedures?
Endoscopy procedures
What is alarm fatigue
A form of human error occurring when a practitioner is desensitized to alarms or alerts
What does the COVERABCD crisis management algorithm stand for?
Circulation, Color
Oxygenation
Ventilation
Endotracheal tube
Review Monitors, Equipment
Airway
Breathing
Circulation
Drugs
Describe the circulation, color assessment
Determine adequacy of circulation, check pulse, blood pressure, ECG, noting oxygenation through assessment and oximetry
Describe the oxygen, oxygen analyzer assessment in COVERABCD
Check oxygen delivery system, hypoxic guard analyzer
Describe the ventilation, Vaporizer assessment
Ventilate by hand to assess breathing circuit and airway patency, assess chest excursion and auscultation, assess etCO2, and check vaporizer function.
Describe the endotracheal tube assessment
includes patiency, seal, stabilization
Describe the review of monitors and equipment assessment
ensure appropriate calibration and maintenance, review any and all equipment in contact with the patient. review the alarm parameters.
Describe the airway assessment in the COVERABCD algorithm
Check the patency of the entire airway, including the non-intubated airwar. Assess for laryngospasm, foreign body, obstruction, bronchospasm, emesis
Describe the breathing assessment in the COVERABCD algorithm
Assess pattern, rate, and depth of respirations; examine, auscultate, review etCO2 and pulse ox monitors
Describe the drugs assessment in the COVERABCD algorithm
Review drugs given, consider needed pharmacologic intervention, consider the possibility of medication admin error
Seeing condensation in an airway device or clear mask can indicate the presence, but not the ______, of gas exchange
adequacy.
Observed retractions and seesaw motion of the chest and abdomen can indicate the presence of?
Airway obstruction
After the initial core temperature drop produced by the peripheral blood redistribution, what modes of heat transfer MOST contribute to hypothermia during general anesthesia?
Radiation
An underdamped arterial transducer system produces ?
An artificially high systolic BP - overestimated BP
Underestimated DBP
PETCO2 is usually how much less than PaCO2
typically 0-5mmHg less than PaCO2 due to the mixing of dead space gas
What are the two methods of sampling gas from in an airway
- Sidestream (diverting)
- Mainstream (nondiverting)
What is sidestream sampling from an airway? pros and cons
sample line external to the airway - aspirates an airway sample.
o Prone to kinking, clogging and water vapor
o Neonates and infants can have dampened waveforms & false low readings
What is mainstream sampling from an airway? cons of this
device is placed directly inside the airway.
o Can add deadspace
o Fragile- easy to damage
What is the most common cause of reduced etCO2
hypotension
most common cause of CO2 rebreathing
incompetent unidirectional valve - change it
A terminal upswing at the end of the capnogram plateau ?
is due to decreases in lung compliance and functional residual capacity
Where in the anesthesia circuit would you find a Wright respirometer?
expiratory limb
A pulmonary embolism would characteristically result in what kind of etCO2 change
a decrease in the ETCO2 relative to the PaCO2
The primary means a newborn infant has to respond to hypothermia is
the increased release of norepinephrine
3 possible reasons/themes of increased etCO2
Increased CO2 delivery/Production
Hypoventilation
Equipment Problems
Name at least three causes of increased etCO2 related to an increase in CO2 delivery/production
Malignant hyperthermia, Fever, Sepsis, Seizures, Increased Metabolic Rate or skeletal muscle activity, Bicarb Administration/medication side effect, clamp/tourniquet release.
Laparoscopic surgery (know this one)
Name at least three causes of increased etCO2 related to hypoventilation
Obesity or Pregnancy, COPD
neuromuscular paralysis or dysfunction, CNS depression, Metabolic Alkalosis (if spontaneously breathing), medication side effect
Name causes of increased etCO2 related to equipment problems
CO2 absorber exhaustion, ventilator leak, rebreathing, malfunctioning inspiratory or expiratory valve.
Name 3 reasons/themes for decreased etCO2
decreased CO2 delivery/production
Hyperventilation
Equipment problems
Name at least 3 causes for decreased CO2 related to delivery/production
Pulmonary Hypoperfusion* due to hypotension, decreased CO
Hypothermia, Hypometabolism, PE, hypovolemia, V/Q mismatch or shunt, autoPEEP, medication side effect
Name causes for decreased etCO2 relating to hyperventilation.
pain/anxiety, awareness “light” anesthesia, metabolic acidosis (if spontaneously breathing), medication side effect
Name causes for decreased etCO2 relating to equipment problems
Ventilator disconnect, esophageal intubation, bronchial intubation, complete airway obstruction or apnea, sample line problems (kinks), ETT or LMA leaks
What factors shift the oxyhemoglobin curve to the right?
Elevated CO2, Elevated Temperature, Elevated 2,3 - DPG, Acidosis - Elevated H+ ions (so decrease pH)
What factors shift the oxyhemoglobin curve to the left?
Decreased CO2, Decreased temperature, Decreased 2,3 - DPG, Alkalosis - Decreased H+ (so increased pH)
When the oxyhemoglobin curve shifts the right, what does this mean regarding the relationship between oxygen and hemoglobin?
O2 is more readily released from hgb at the tissue level
When the oxyhemoglobin curve shifts the left, what does this mean regarding the relationship between oxygen and hemoglobin?
Greater attachment of O2 to hgb, thereby decreasing release to tissues
The oxygen-carrying capacity is mainly dependent on the?
the amount of hemoglobin
Does the pulse ox over or underestimate spo2 in the presence of carbon monoxide
Overestimates the hemoglobin saturation. CO replaces hemoglobin. Because they absorb the same red light wavelength, leading to false overestimation. left shift curve
What is the equation for Flow? (Respiratory Flow)
Volume/Time
delta-V over delta-T
What is Peak Expiratory Flow Rate (PEFR)
Maximum slope of the flow curve. Where flow is the greatest.
The most/ how much volume is exhaled over the shortest time.
How does residual volume compare to normal lungs in patients with obstructive lung disease(s)?
They can’t get as much air out, so the residual (or left-over) volume in the lung is higher in those with obstructive lung disease.
How does Total Lung Capacity compare to normal lungs in patients with obstructive lung disease(s)?
TLC is larger in patients with obstructive lung disease such as COPD.
Primarily due to the destruction of lung tissue, leading to a loss of elastic recoil, which allows the lungs to expand to abnormally large volumes, causing air trapping and resulting in lung hyperinflation
Identify and Explain Numbers 1-4 on the image
- PEFR. Peak Expiratory Flow Rate: The most/ how much volume exhaled over the shortest time.
- Total Lung Capacity (TLC): The maximum amount of air that can be inhaled
- Residual Volume (RV): How much air is left in the lungs after expiration.
- Forced Vital Capacity (FVC): Total Expired Air. =TLC-RV
How does residual volume compare to normal lungs in patients with restrictive lung disease(s)?
The Residual Volume decreases. As less air comes in, there is less total air left in the lungs after expiration.
How does inspiratory flow compare to normal lungs in patients with restrictive lung disease(s)?
Inspiratory flow decreases. Difficult time getting air in, so less volume over time entering lungs
How does total lung compliance compare to normal lungs in patients with restrictive lung disease(s)?
Decreased. You have decreased compliance so less total air can enter on inspiration.
How does Peak Expiratory Flow Rate (PEFR) compare to normal lungs in patients with restrictive lung disease(s)?
Decrease. If you have less volume coming in, you will have less volume coming out. Flow is Volume over time.
How does Forced Vital Capacity (FVC) compare to normal lungs in patients with obstructive lung disease?
FVC will decrease. Patients can’t exhale as much volume to do diseased/obstructed airways
How does Forced Vital Capacity (FVC) compare to normal lungs in patients with restrictive lung disease?
FVC will also be decreased in restrictive lung disease patients because less air can be inhaled, meaning less will be exhaled compared to normal lungs.
Why is there coving on obstructive lung disease flow volume loops but not in restrictive?
Restrictive lung disease has no problem exhaling; the problem is an inspiration. Obstructive has difficulty exhaling, making the curve cove inward.
What is the equation for lung compliance?
Volume / Pressure
Delta V over Delta P
What is lung compliance?
The ability of the lung to expand
What lung pressure are we talking about when discussing lung compliance?
The distending pressure AKA Transmural Pressure
Compliance is the opposite of?
Surface Tension and Elasticity
equation from Fahrenheit to Celsius
C= 5/9(F-32)
Equation from Celsius to Fahrenheit
F=9/5C + 32
