Positive End-expiratory Pressure Peep Quiz

PEEP (Positive End-Expiratory Pressure) is a mechanical ventilation technique that helps maintain lung volume during expiration. In a tension pneumothorax, air accumulates in the pleural space, causing lung collapse and increased pressure in the chest cavity. Applying PEEP in this condition can exacerbate the tension pneumothorax by further trapping air in the pleural space, leading to increased lung collapse and compromised cardiac output. Therefore, using PEEP is contraindicated in cases of tension pneumothorax.

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.

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.

Decreased compliance = stiffer lungs
therefore, higher pressures

→ Bc you are in the Flow-Time graph and it's rectangular waveforms

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.

the expiratory flow doesn't return to baseline

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.

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.

2.2 lb = 1 kg

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.

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)

Etime = 2.25 - 0.75

It's for oxygenation!

Bc you have air trapping... you will have some permissive hypercapnea and that's ok

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.

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.

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.

Mercury values are smaller than water values.

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.

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.

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.

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.

→ Bc this is Pressure-Time graph and its Rectangular Waveform.

The rest is true of Pressure Control

This is an assisted breath; NOT spontaneous.
So much be in PC-CMV or AV-VC mode.

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.

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.

(actual PIP)(actual CO2) = (desired CO2)(desired PIP)
(desired FiO2)(desired PaO2) = (actual FiO2)(desired FiO2)

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.

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

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.

Dyanmic CL = VT / (PIP-PEEP)
= 500 / (28-0)
=

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.

→ Bc this is Pressure-Time graph and its Exponential Rise.

This is a picture of overdistension. you need to decrease PIP

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.

2.2 lb = 1 kg

MV information is not important to this equation.

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

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!***

This is a picture of decreased CL.
Emphysema & increased surfactant causes INCREASED COMPLIANCE (picture on the LEFT).
COPD is a RAW issue. not CL

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.

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

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)

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)

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

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.

→ 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)

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.