1.
You just started your patient on a CPAP weaning trial, what's the minimum amount of time you should wait before drawing an ABG?
Correct Answer
B. 15 min
Explanation
The minimum amount of time you should wait before drawing an ABG after starting a CPAP weaning trial is 15 minutes. This is because it takes some time for the patient's oxygen and carbon dioxide levels to stabilize after initiating CPAP therapy. Waiting for at least 15 minutes allows for these levels to reach a steady state, providing a more accurate assessment of the patient's respiratory status.
2.
Patient's IBW is 78 kg. His exhaled tidal volume is 500 mL (close to 7 ml/kg) at RR of 14 breaths/min. And there is a measured mechanical deadspace of 30 mL in the tubing and HME. Calculate the Alveolar Volume.
Correct Answer
B. 298 mL
Explanation
2.2 lb = 1 kg
3.
Patient's IBW is 52 kg. Her exhaled tidal volume is 350 (close to 7 ml/kg) with a RR of 10. This creates a MV of 3.5 LPM. Measured mechanical deadspace for the tubing and HME is 30 mL. Calculate Alveolar Ventilation.
Correct Answer
A. 2.06 LPM
Explanation
2.2 lb = 1 kg
MV information is not important to this equation.
4.
Patient's IBW is 132 lbs. Exhaled tidal volume is 420 mL (7ml/kg). MV is 5.0 LPM. Mechanical deadspace volume from the extra tubing and HME is ~40 mL. Calculate Alveolar Volume.
Correct Answer
A. 248 mL
Explanation
The alveolar volume can be calculated by subtracting the mechanical deadspace volume from the exhaled tidal volume. In this case, the mechanical deadspace volume is given as 40 mL and the exhaled tidal volume is given as 420 mL. Therefore, the alveolar volume would be 420 mL - 40 mL = 380 mL. However, since the question asks for the alveolar volume in mL per kg, we need to divide the alveolar volume by the patient's weight in kg. Since the patient's IBW is given as 132 lbs, we need to convert it to kg by dividing it by 2.2 (1 kg = 2.2 lbs). Therefore, the alveolar volume would be 380 mL / (132 lbs / 2.2 lbs/kg) = 380 mL / 60 kg = 6.33 mL/kg. Therefore, none of the given answer choices are correct.
5.
What are some possible causes for an increase in PIP?
Correct Answer(s)
A. Bronchospasm
B. Secretions
D. Tube Obstruction
E. Decreased compliance
Explanation
Decreased compliance increases PIP!!! Not an increase in compliance because that would decrease PIP.
Emphysema does not increase PIP because emphysema is a disease which increases CL.
6.
Which of the following is true
Correct Answer(s)
B. This is an airway resistance (RAW) issue
D. Only PIP is increasing while Pplat stayed the same
F. Pta = PIP - Pplat
Explanation
Pta = PIP - Pplat
Thus, you can see that PIP is increasing, and Pta is increasing as well!
This means the difference btwn PIP and Pplat is increasing.
Thus, PIP is increasing but Pplat is staying the same.
That means this is a RAW issue.
Also, it is not a CL dynamic nor static issue because these values stayed the exact same in the table. Also, if it were a CL issue, then PIP and Plat must increase together.
7.
Which of the following is/are true?
Correct Answer(s)
A. This is a compliance (CL) issue
D. PIP and Pplat are increasing together at the same interval
Explanation
Pta = PIP - Pplat
Since Pta is staying the same, you can tell that PIP and Pplat are increasing at the same interval. You can also see that because the PIP increases by 5 and so does Pplat.
8.
Which of the following is/are true?
Correct Answer(s)
B. This is an airway resistance (RAW) issue
C. Only PIP is increasing while Pplat stayed the same
Explanation
The given answer states that this is an airway resistance (RAW) issue. This means that there is a problem with the resistance in the patient's airway, which is causing an increase in the peak inspiratory pressure (PIP). However, the plateau pressure (Pplat) remains the same. This suggests that the problem is specifically related to airway resistance, rather than a general increase in pressure throughout the respiratory cycle.
9.
Which of the following is/are true?
Correct Answer(s)
A. Compliance in improving
D. PIP and Pplat are decreasing together at the same interval
Explanation
The answer states that compliance is improving, which means that the lungs are becoming more elastic and easier to inflate. It also states that both PIP and Pplat (peak inspiratory pressure and plateau pressure) are decreasing together at the same interval. This indicates that the airway resistance is decreasing and the lungs are able to expand with less pressure. Overall, the answer suggests that the respiratory system is functioning better and becoming more efficient.
10.
Which of the following is true?
Correct Answer
D. This is because PEEP is increasing
Explanation
The correct answer is "This is because PEEP is increasing." When positive end-expiratory pressure (PEEP) is increased, it can lead to a decrease in lung compliance. PEEP is the pressure maintained in the lungs at the end of expiration, which helps to keep the airways open and improve oxygenation. However, excessive PEEP can cause overdistension of the alveoli and reduce lung compliance, making it harder for the lungs to expand and causing a decrease in compliance. This can be seen by an increase in airway pressure during inspiration (PIP) while plateau pressure (Pplat) remains the same.
11.
Patient is in PC-CMV with PIP of 25 and RR of 12. What happens if there's an increase in RAW or decrease in compliance?
Correct Answer
A. Volumes decrease
Explanation
In pressure control, PIP and RR are set; whereas, tidal volume varies.
So PIP cannot increase/decrease. And neither can RR.
Volume will DECREASE because increased RAW and/or decreased CL causes higher PIPs... cutting the breath off earlier and causing a loss in VT.
12.
Check all of the correct cuff pressures.
Correct Answer(s)
B. 20-25 mmHg
C. 27-34 cmH2O
Explanation
Mercury values are smaller than water values.
13.
Minimal Leak Technique occurs when you listen over the suprasternal notch or lateral neck, and inflate the cuff just until no leak is heard at end inspiration.
Correct Answer
B. False
Explanation
That is Minimal Occlusion technique.
The MLT has an extra step --> then a small amount of air is removed until leak can just be heard at end-inspiration
14.
Patient is 5'10" with an IBW of 73 kg. He is in AC-VC with 500 mL tidal volume and a RR of 14 on FiO2 of 40%.The following ABG comes back: pH 7.33, PaCO2 50, PaO2 55, HCO3 of 22. What would you change on the vent if you want a desired PaCO2 of 40 and a desired PaO2 of 70?
Correct Answer
A. Increase RR to 18. Increase FiO2 to 50%
Explanation
You don't want to increase VT because 500 mL is already at his 7mL/kg of IBW. You want to increase RR instead.
(desired MV)(desired CO2) = (actual MV)(actual CO2)
(desired FiO2)/(actual FiO2) = (desired PaO2)(actual PaO2)
15.
You are in PC-CMV with a PIP of 23 and RR of 12 with FiO2 of 50%. You draw the following ABG: pH 7.32, PaCO2 50, PaO2 70, HCO3 of 24. What vent settings would you change if you want a PaO2 of 80 and PaCO2 of 40 WITHOUT changing the RR (want to leave RR at 12).
Correct Answer
A. Increase PIP to 29. Increase FiO2 to 57%
Explanation
(actual PIP)(actual CO2) = (desired CO2)(desired PIP)
(desired FiO2)(desired PaO2) = (actual FiO2)(desired FiO2)
16.
Pt is on AC-VC and there's an increase in RAW. Select all that is true.
Correct Answer
A. PIP increases
Explanation
If you are in VC... you have a set Volume and RR.
Thus, the only thing that can change is PIP.
Increasing RAW will increase PIP.
17.
If someone is in VC and Pplat increases, what has happened to the compliance?
Correct Answer
A. Decreased
Explanation
Decreased compliance = stiffer lungs
therefore, higher pressures
18.
Select all that is true
Correct Answer(s)
A. Normal RAW = 0.5-2.4 cmH2O/L/sec
E. Normal Static Compliance = 70-100 mL/cmH2O
F. Normal Dynamic Compliance = 40-70 mL/H2O
Explanation
The correct answer is "Normal RAW = 0.5-2.4 cmH2O/L/sec, Normal Static Compliance = 70-100 mL/cmH2O, Normal Dynamic Compliance = 40-70 mL/H2O." This is because the given ranges for RAW, static compliance, and dynamic compliance fall within the normal values for these parameters. RAW refers to airway resistance, which is the pressure difference between the airway opening and the alveoli divided by the flow rate. Normal RAW values are typically between 0.5-2.4 cmH2O/L/sec. Static compliance refers to the ability of the lungs to expand and is typically between 70-100 mL/cmH2O. Dynamic compliance refers to the compliance of the lungs during airflow and is typically between 40-70 mL/H2O.
19.
Select all that is true about RED DOT A...
Correct Answer(s)
A. This is the lower inflection point
C. This is the point at which a large # of alveoli are recruited
E. PEEP can be set a little above this point
G. This is important for ARDS
Explanation
RED DOT A = lower infection point
- you can set PEEP a little bit above this point --> so a large # of alveoli are recruited.
- this is important for ARDS bc with ARDS pts you have extreme difficulty oxygenating... so you can set PEEP a little above this point.
The rest of the answers are true for RED DOT B! That is the upper inflection point.
- you can set the PIP a little below this point
- going above causes overdistention of the alveoli
20.
Check all the causes of Metabolic acidosis
Correct Answer(s)
B. Aspirin (and other drug ingestion)
E. DKA
G. Lactic Acid
J. Diarrhea
K. Pancreatitis
M. Renal Failure
Explanation
The rest of the answers are causes of Metabolic ALKALOSIS, not acidosis.
A way to remember the Acidosis causes is:
- all words that in "acid" (ie diabeteic ketoacidosis, lactic acid)
- Pam's Kidding About Diarrhea
- Pam = pancreatitis
- Kidding = kidneys = renal failure
- About = Aspirin
- Diarrhea
Ways to remember alkalotic causes:
- all the "Hypos" (kalemia, chloremia, volemia --> diuretics) bc you are "losing" everything until you reach the bare "basics" (base = alkalosis)
- conditions where you get rid of body acid (ie vomiting, NG sxning)
- increase bicarb (NaHCO3 infusion/ingesting)
21.
Your pt is still respiratory acidotic despite increasing their alveolar ventilation. What could they potentially have?
Correct Answer
A. Pulmonary embolism
Explanation
Respiratory Acidosis = not blowing off CO2
But you increase alveolar ventilation...
So this means you have a DEADSPACE issue (ventilation without perfusion).
The only one which causes a decrease in perfusion is a PE!
LOW PEEP does NOT decrease venous return... HIGH PEEP does!***
22.
PEEP is for ventilation
Correct Answer
B. False
Explanation
It's for oxygenation!
23.
At what conditions would you increase PEEP instead of increasing FiO2?
Correct Answer(s)
A. FiO2 >= 60%
B. P/F ratio < 300
E. Refractory Hypoxemia
Explanation
When the FiO2 is already at or above 60%, increasing the FiO2 further would not be effective in improving oxygenation. In this case, increasing PEEP (positive end-expiratory pressure) would be a better option to improve oxygenation. Additionally, if the P/F ratio is less than 300 or if the patient is experiencing refractory hypoxemia (oxygenation cannot be improved despite other interventions), increasing PEEP would be preferred over increasing FiO2.
24.
What are some contrindications for APRV?
Correct Answer(s)
A. COPD
B. Guillan Barre
C. Myasthenia gravis
F. Someone who needs heavy sedation
G. Cerebral edema w/increased ICP
Explanation
The rest of the answers are INDICATIONS for using APRV.
You don't want to use APRV on someone with a neuromuscular disease (GB, MG), or someone who needs heavy sedation (cerebral edema with increased ICP), or someone who air traps (COPD)
The rest are good answers for indications for APRV (post surgery atelectasis and difficulty oxygenating). And you need mild sedation on APRV
25.
Check all that are the Acute Phase of ARDS:
Correct Answer(s)
A. Inflammation
B. Hypoxemia
D. Alveolar filling
Explanation
The acute phase of ARDS is characterized by inflammation, alveolar filling, and hypoxemia. Inflammation refers to the immune response that occurs in the lungs, leading to damage and fluid accumulation. Alveolar filling refers to the filling of the alveoli with fluid, impairing gas exchange. Hypoxemia is a condition where there is low oxygen levels in the blood, which is a common feature of ARDS. These three symptoms are commonly observed during the acute phase of ARDS. The other options, such as fibrosing alveolitis, decreased CL (compliance), and pulmonary fibrosis, may occur in later stages or as a consequence of the acute phase.
26.
Check all that are the SubAcute Phase of ARDS:
Correct Answer(s)
C. Fibrosing alveolitis
F. Decreased CL
Explanation
The SubAcute Phase of ARDS is characterized by fibrosing alveolitis and decreased CL. Fibrosing alveolitis refers to the inflammation and scarring of the alveoli, leading to impaired gas exchange. Decreased CL, or decreased lung compliance, indicates stiffening of the lungs, making it difficult for them to expand and contract properly. These two factors contribute to the impaired lung function seen in the subacute phase of ARDS.
27.
Check all that are the Chronic Phase of ARDS:
Correct Answer
F. Pulmonary fibrosis
Explanation
The correct answer is pulmonary fibrosis. Pulmonary fibrosis is a characteristic feature of the chronic phase of ARDS. It refers to the scarring and thickening of lung tissue, which can impair lung function and lead to respiratory difficulties. Inflammation, alveolar filling, hypoxemia, decreased CL (compliance), and fibrosing alveolitis are all associated with the acute phase of ARDS, rather than the chronic phase.
28.
Check all the things that help with ARDS:
Correct Answer(s)
A. Albuterol
B. Proning
C. High PEEP
G. Low VT
H. High RR
Explanation
Albuterol is a bronchodilator that can help improve airflow and oxygenation in patients with ARDS. Proning refers to positioning the patient face down, which can help improve oxygenation by redistributing lung perfusion. High PEEP (positive end-expiratory pressure) helps keep the alveoli open during expiration, improving oxygenation. Low VT (tidal volume) is recommended to prevent lung injury in ARDS patients. High RR (respiratory rate) can help maintain adequate ventilation. Therefore, Albuterol, Proning, High PEEP, Low VT, and High RR are all helpful in managing ARDS.
29.
Which are the two most common pressure scalars?
Correct Answer(s)
A. Rectangular
B. Exponential rise
Explanation
Rectangular and exponential rise are the two most common PRESSURE scalar waveforms.
Whereas rectangular and descending ramp are the two most common FLOW scalar waveforms.
30.
How long is the inspiratory time and expiratory time?
Correct Answer
B. Itime = 0.75... Etime = 1.5 sec
Explanation
Etime = 2.25 - 0.75
31.
Calculate Static CL and RAW
Correct Answer(s)
B. RAW = ~0.16
D. CL static = 36
Explanation
RAW = PIP-Plat / Flow
= (22-16)/38
RAW = 0.16
CL static = VT / (Plat - PEEP)
= 400 / (16-5)
= 36
32.
Which of the following is true of this picture?
Correct Answer(s)
A. It is in PC
D. You need to increase the sensitivity
E. There is a PEEP ~ 10 cmH2O
Explanation
The trigger is NOT sensitive enough! Patient is trying to trigger the breath, but the vent is not following through with a breath.
Increase sensitivity = more sensitive so pt can have a easier time trigger the vent.
You can tell this is in PC because the Pressure-Time Scalar has exponential rise waveforms.
And the Flow-Time Scalar has Descending Ramps!
The PIP is NOT 50 cmH2O. It is ~25 cmH2O.
Whereas the Peak FLOW is ~50 LPM
33.
What does this picture show?
Correct Answer(s)
A. The rise-time is too fast
C. Too much turbulence through the ETT
D. Pressure spike is called an overshoot
F. Fix this by increasing the rise time
Explanation
The rise-time is too fast --> causing a blast of air into the ETT --> too turbulant --> causing a pressure spike called an overshoot
Fix this by INCREASING rise time (to make it slower)
34.
Calculate Dynamic Compliance
Correct Answer
A. 18 mL/cmH2O
Explanation
Dyanmic CL = VT / (PIP-PEEP)
= 500 / (28-0)
=
35.
What should you do to fix this?
Correct Answer
A. This is an obstruction... Give a bronchodilator
Explanation
The correct answer suggests that the given situation is an obstruction, which means there is a blockage in the airways. To fix this, the recommended action is to give a bronchodilator. Bronchodilators help to relax and open up the airways, making it easier for the person to breathe.
36.
What ventilator mode are you most likely in?
Correct Answer
C. CPAP
Explanation
This is a spontaneous breath, so it must be in CPAP mode.
AC-VC and PC-CVM do not allow for spontaneous breaths; only assisted breaths.
37.
What ventilator mode are you most likely in?
Correct Answer
A. PC-CMV or AC-VC
Explanation
This is an assisted breath; NOT spontaneous.
So much be in PC-CMV or AV-VC mode.
38.
What mode are you in?
Correct Answer
A. Volume Control
Explanation
→ Bc you are in the Flow-Time graph and it's rectangular waveforms
39.
What mode are you in?
Correct Answer(s)
B. Pressure Control
C. Volume Control with Auto-Flow
Explanation
→ Bc this is Flow-Time graph and its Descending ramp.
→ This is also the Flow-Time graph for Volume control with auto-flow (which is basically pressure control)
40.
What mode are you in?
Correct Answer
B. Pressure Control
Explanation
→ Bc this is Pressure-Time graph and its Rectangular Waveform.
41.
What mode are you in?
Correct Answer
A. Volume Control
Explanation
→ Bc this is Pressure-Time graph and its Exponential Rise.
42.
Which is true about Volume Control?
Correct Answer(s)
A. Constant flow with rectangular waveforms
C. Pressure waveform is exponential rise (varying with lung characteristics)
Explanation
The rest is true of Pressure Control
43.
What kinds of disease explain the picture on the RIGHT side.
Correct Answer(s)
A. ARDS
C. CHF
D. Atelectasis
E. Decreased surfactant
Explanation
This is a picture of decreased CL.
Emphysema & increased surfactant causes INCREASED COMPLIANCE (picture on the LEFT).
COPD is a RAW issue. not CL
44.
Which of the following is/are true?
Correct Answer(s)
A. Volume control
C. There is some air trapping
Explanation
Inspiration is on top (positive). Expiration is on bottom (negative).
So you see the inspiration side is a rectangular waveform. And this is a FLOW-volume loop.
So you know this is VC.
You CANNOT tell if there is PEEP! Because you are in the FLOW loop... you have no idea what the PIP/Plat/PEEP are!!
The same is true about "overdistension." You cannot tell with a Flow loop.
This is not normal. You can see that on the expiration side (bottom), it does not return to zero. Therefore, you have air trapping.
45.
What mode are you in?
Correct Answer
B. Pressure control
Explanation
Inspiration is on top (positive). Expiration is on bottom (negative).
So you see the inspiration side is a DESCENDING waveform. And this is a FLOW-volume loop.
So you know this is Presssure ctrl.
46.
Select all that is true regarding this Flow-Time graph.
Correct Answer(s)
A. The Flow Cycle % is 20%
C. This flow cycle is best for restrictive disease / difficult to oxygenate
F. This could be in VC with auto-flow ON mode
G. This could be in PC mode
H. This allows for longer inspiration
Explanation
Descending ramp in FLOW-volume loop.
Flow Cycle % = end of inspiration/peak of inspiration
Since the flow cycle is a relatively small percentage... it is for RESTRICTIVE or those DIFFICULT TO OXYGENATE... allowing for LONGER inspiration
47.
Which is true about initial settings for APRV?
Correct Answer(s)
A. Set P-low = 0
C. Set T-low = 0.8... then adjust to 50% of the expiratory flow in the Flow-Time scalar.
G. I time is longer than E time
J. Set P high = Plat
L. You need to make sure MAP < 30
Explanation
You don't record VT! You record the MV and the Pplat.
While PIP should technically be less than 30... you want to set P high to Pplat.
48.
Which are hallmarks of ARDS
Correct Answer(s)
A. Hypoxemia
B. Decreased lung compliance
D. Reduced lung volume
Explanation
ARDS, or Acute Respiratory Distress Syndrome, is a condition characterized by inflammation and fluid accumulation in the lungs, leading to severe respiratory failure. The hallmarks of ARDS include hypoxemia, which is a low level of oxygen in the blood due to impaired gas exchange in the lungs. Additionally, ARDS is associated with reduced lung volume, as the accumulation of fluid and inflammation causes the lungs to become stiff and lose their ability to expand fully. This results in decreased lung compliance, meaning the lungs are less able to stretch and expand during breathing.
49.
Permissive hypercapnea is allowed in ARDS
Correct Answer
A. True
Explanation
Bc you have air trapping... you will have some permissive hypercapnea and that's ok
50.
Regarding the last question (the Flow-Volume Loop is pictured here)... What would you do to fix the air trapping that is occurring?
Correct Answer(s)
A. Increase the E time
C. Albuterol
D. Decrease the RR
E. Increase extrinsic PEEP
Explanation
Albuterol can be a good answer! It can be yes or no.
If it is air trapping due to something like COPD or asthma... then albuterol will help.
If it is air trapping bc your RR is too high, then it will not help!
Sometimes when you are air trapping (high PEEPi = intrinsic PEEP), you can help release that air by increase the extrinsic PEEP. This sounds really counter-intuitive and silly... but sometimes it does work. Especially if you are air trapping bc the alveoli aren't staying open/collapsing.