Spontaneous Breathing Flashcards
What is ventilation?
Ventilation is movement of Air in and out of the lungs
What is the main porpose of Ventilation?
The main porpose of Ventilation is to bring O2 for gas Exchange into the Lungs and allow CO2 Exhalation.
What is Respiration?
Movement of gas molecules across of membrane
How many types of respiration exist, and the different between them?
- External Respiration: It happens in the Lungs,**O2 moves from the alveoli into the blood stream, and CO2 moves from Blood stream into the alveoli.
- Internal Respiration: It happens in the cells, CO2 moves from the cells into the blood, and oxygen moves from the blood into the cells
Normal Inspiration consist of:
Inspiration occurs when inspiratory muscles contract.
- Diaphragm decends, size of the thorax enlarges vertical
- External Intercostal muscles contracts and rise the ribs slightly, thorax cincurference increases.
What we called work of breathing?
We called WOB at the muscles activity required to bring air into the Lungs.
Does Normal Exhalation require any muscles activity? Why.
No, because is a passive activity (Not WOB), does not riquire any muscle effort (muscles relax).
What is the relation between Gas Flow and Pressure gradient?
Pressure Gradient is necesary for Air to Flow through the Airway, pressure at one ends must be higher than the other ends. ( Air always moves from hight pressure to low pressure)
PTA stand for?
Transairway Pressure
(PTA = PIP-PPLAT)
PAW stand for?
Airway Pressure
PA stand for?
Alveolar pressure
TRUE or FALSE
Gas Flow into the Lungs when pressure in the alveoli is lower than the pressure at the mouth and nose?
TRUE
When pressure in the Alveoli and mouth are the same, Gas will do what?
- Flow out of the Alveoli
- Flow into the Lungs
- No flow will occur
- None of the above
No Flow will occur, because there is not pressure gradient
The formula use to identify the difference between Resintance and Compliance is call?
Transaiway Pressure (PTA)
PTA= PIP- PPLAT
On Spontaneous Breathing During Inspiration, Intrapulmonary pressure will be Positive or Negative?
Negative, (during inspiration Intrapulmonary Pressure decreases but increases in volume, alowing air to move into the Lung from the atmosphere)
- Ribs moves up
- Diaphragm flattens
- Volume chest increases

On Spontaneous Breathing, Intrapulmonary Pressure exhalation will be Positive or Negative?
Positive

It’s true that intrapleural pressure is negative only on Inspiration?
yes, but only on Spontaneous Breathing, (Intrapleural Pressure in negative during Inspiration and Expiration, the only difference is that during expiration is less negative than Inspiration)

Lung Compliance (CL) is?
How well the Lungs stretch, the easy the Lung stretches, higher the compliance will be.
(V/P)
Airway Resistant (RAW) is?
Basically refer to the fiction of the tissues and organs to the air flow during breating. (afecting primarily exhalation)
(RAW: PTA /Flow)
(PTA = PIP-PPLAT)
Matematically how we get Lung Compliance?
V/P, (Volume divided by Pressure)
What is the total Compliance for Spontaneous Breathing? and the Range?
The Total Compliance is about 100mL/cm H2O and the range is between 50 - 170 mL/cm H2O
For Intubated and mecanically ventilated patients, compliance varies from?
35- 50 mL/cm H2O
Static Compliance is refered when?
When compliance is measured under conditions of no gas flow.
What is Dynimic Compliance?
Is the combination of Lung Compliance and Air way resistant.
C<span>D</span> = Lung compliance and RWA
CD = VT/ PIP-PEEP
When we measured compliance where there is no gas flow at all this is call?
Static Compliance, ( Static Compliance is very importat because it tell uss how compiance the lungs are)
Transairway Pressure helps us to diferenciate between:
RWAand Lung Compliance
What is Mechanical Ventilation?
Is the artificial inflation of lungs by an external, mechanical device.
How Mechanical Ventilation operates?
It operates by creating negative or positive pressure.
Advantages of Negative Pressure Ventilation (NPV)
- Upper Arway can be maintained without the use of endotracheal or tracheostomy tube.
- Patient can talk.
- Fewer physiological disadvantages than positive pressure.
Negative Pressure Ventilation (NPV) Disadvantages
- Decrease accessibility to the patient.
- Abdominal pooling.
- Decrease venous return, cardiact output, systemic blood pressure (hypotention) tank shock.
NPV have primarily been replaced by :
Positive Pressure Ventilators that use mask, nasal device, endotracheal or tracheostomy tube.
Is a device that puches air into the patient’s lungs through an endotracheal tube mask?
Positive pressure Ventilation (PPV)

PPV Graphic, iniciation and ends
- Here On Inhalation, Intrapulmonary pressure starts at 0 base line and ends up on the positive side
- On Inhalation, Intrapleural Pressure starts on the negative side but it ends up on the possitive side
- Now on Exhalation, Intrapulmonary Pressure starts on the positive side and ends up on zero base line.
- So does Intrapleural pressure but this one ends up on the negative side

Identify Spontaneous Inhalation and Exhalation Graphics
- Here on Inhalation Intrapulmonary Pressure starts on zero base line,making an slightly negative curve finishing on zero base line.
- Also on inhalation, Intrapleural Pressure starts on the negative side, increasing during inhalation finishing even more negative.
- Now on Exhalation, Intrapulmonary Pressure, starts on zero base line making slightly positive curve, finishing on zero base lane.
- On exhalation Intrapleural Pressure, starts on negative side, decresng slightly during exhalation to ends up less negative.

What is base line Pressure?
Is the pressure in the airway when the patient is not breathing, usually is zero.
What is PIP
Peak inspiratory pressure (PIP) is the highest level of pressure applied to the lungs during inhalation.

What is Plateau Pressure?
Is the amount of pressure require to stretch the alveoli
If Plateau pressure represent Lung Compiance then, What represent PIP?
PIP represent Lung Compliance and Airway Resistant.
What ventilator device allows spontaneous breathing.
CPAP
PEEP vs CPAP
- PEEP increase atmosphere pressure on exhalation preventing normal exhalation
- CPAP is an spontaneous breathing device that increase pressure on inspiration
What is Peak Pressure?
- Is the hieght pressure recored at the end of inspiration (PIP)
- It is the sum of two pressures (pressure requires to force gas through the resistance of airways, and pressure require to fill alveoli)
When Plateau Pressure is measured?
It’s measured after breath has been delivered and before exhalation begins.
The diference between Plateau and PIP pressure is?
Transairway pressure
PTA = PIP-PPLAT
What is Auto PEEP (Intrinsic PEEP, occult PEEP)
Is air trapping, it happen when the patient does not have enough time to exhale because of breathing too fast.

How we fix Auto PEEP?
- Increasing Expiratory Time
- Decreasing RR (but this will affect VE)
- ↑ Flow
- ↓ Inspiratory Time
How we get Dynamic Compliance? (matematically)
CD= VT/(PIP-PEEP)
VT 500ml, PIP 30cm H2O, PPLAT 25 cm H2O, PEEP 5 cm HO.
CD = 500/(30-5)
CD = 500/25
CD = 20ml
How we get Static Compliance (matematically)
CS=VT/PPLAT-PEEP
VT500, PIP 30cm H20, PPLAT 25 cm H2O, PEEP 5 cm H2O.
CS = 500ml/ (25 cmH2O - 5 cm H2O)
CS = 500ml/ 20cmH2O
CS = 25ml
How we fix Ventilatory failure (Hypoventilation) in a ventilator?
By:
- Increasing Vt
- Increasing RR
How we fix Hypoxemia in a ventilator?
By:
- Increasing Airway Pressure ↑PEEP (pressure makes lung bigger creating more suface for gas Exchange)
- ↑FiO2 Giving more Oxygen
How we fix Hyperventilation on a patient that is on a Ventilator?
By:
- Decresing Tidal Volume (Vt)
- Decreasing RR
Disadvantages of Positive PressureVentilation:
Multi-System Effects:
- Renal System
- GIS
- Hepatic System
- Cardiovascular System
- Neurological Sysem
- Respiratory System
Most important factor is decreased Cardiac Output
What will happen to a patient when Plateau Pressure is over 30 cm H2O?
Increase patient’s risk for Ventilator induced Lung Injury
What pressure is necesary for gas flow to get inito the Lungs?
Transairway pressure
(PTA= PIP - P<span>PLAT</span>)
We get Transairway Pressure By substructing Airway Pressure from Alveolar Pressure (PA)
Transairway Pressure more than 10 cm H2O means?
Airway Resistant
How we get Airway Resistant?
RWA = PTA/Flow
(PTA = PIP-PLAT)
Normal Values:
- Normal: 0.6 - 2.4 cm H2O.(Spontaneous)
- Intubated: >6 cm H2O
Are these condictions asociated with PIP or Plateau pressure
- Bronchospasm
- Retained secretions
- Mucous plug
- ETT tip occlusion
PIP pressure, because they are Airway Issues
(Airway resistance)
Are these condictions related to PIP or Plateau pressure and why?
- Pneumothorax
- Pulmonary edema
- ARDS
- Pneumonia.
Plateau Pressure, because all these issues compliance is there problem.
What has to happen for gas to Flow in the Lungs?
Pressure in the alveoli must be lower than the pressure in the mouth and nose (Pressure Gradient)
Exhalation is a passive process but, what happen when a patient starts using accesory muscles to exhale?
Most likely the patient have an obstructive problem. When this happened, airways narrowed producing air trapping.
What will affect inspiration, Decreased Lung Compliance or Airway Resistance?
Decrease Lung Compliance.
What will affect expiration, Lung compliance or Airway Resistance?
Airway Resistance.
How NPV Graph look like?

This is call?

Chest Cuirass
This is?

Iron Lung.
It’s a negative chamber.
What is PIP?
It’s the heights pressure in the lung during inspiration

Obstructive Diseases affects the Airway Or Lungs?
The Airway, because ↑ resistance to gas flow
Restrictive Diseases affects Airway or Lungs?
The lungs, Because restriction will make lung difficult to expand normally.