Conventional Vent Flashcards
What is the goal when you first meet the baby at delivery?
Get the lung inflated
Oxygen is a ___________ gas.
It produces lots of _____ _______.
Poisonous
Free radicals
__% of CO goes to the lungs in fetus
When stressed can be ___%
7%
1%
The goal during transition is to have ___% of blood from right heart go to the lungs
100%
The lung inflates by ___ times in the DR that as in utero
4 x’s
There is an ___ -fold increase in pulmonary blood flow in the DR
8
In the DR, PVR immediately plummets by?
1/2
T/F: establishment of oxygenation and ventilation is independent of FiO2 used to establish the initial lung inflation.
True
O2 may delay baby’s first breath by ____ seconds.
24
NPR: use ___% O2 w/term
Use ___-___% w/preterm
Must rely on _____ ______ to determine O2 need.
21%/RA
21-30%
Pulse oximetry
NRP: O2 sats should be:
By 1 minute
by 5 minutes
by 10 minutes
60-65%
80-85%
85-95%
A study done of < 32 wkrs on RA vs 100% FiO2 showed which was better?
Neither, somewhere in the middle, follow institution guidelines
What pH is indication of Acute Respiratory failure?
PaO2?
What would you do?
pH 7.2 and falling
Inability to maintain > 50 w/O2
Give some PPV through CPAP or ETT & Surfactant admin
A PaO2 correlates w/SpO2’s around ___%
85%
Is Apnea a sign of Respiratory Distress?
No
Respiratory Failure
Respiratory Failure is defined by what?
Blood gases (pH too low, PaCO2 too high)
Respiratory Distress is a ________ ________.
Physical Finding:
Increased WOB, tachypnea, retractions, cyanosis
Try only provide ventilation for RDS/Resp Failure?
Respiratory Failure
Reasons for Apnea?
What will you see?
CNS injury
Apnea of Prematurity
**(2 most common)
High CO2, but oxygenate pretty well (b/c have inflated lung)
HMD/Alveolar Dz/Pneumonia babies do what?
So their problem is ____ not ___
Shunt blood b/c lung is collapsed
O2, not CO2
Most important concept to understand is:
The Massive Residual Volume of a babies lungs.
They have a large residual capacity.
What is the typical Vt set on vent?
5 cc/kg
What is the residual capacity of an infant?
25 cc/kg
If there’s an obstruction, baby can get air ___ but can’t get air ____.
Will result in a ___ level of _____.
in
out
high, CO2
Lawyers have decided a preemie <1500 gms is at risk of ROP if PaO2 is >___.
> ____ is a medical, legal emergency
> 80
> 100
BOOST and support trials concluded that targeted Sats
< 90
What happened in the ‘60’s when babies w/HMD were grunting (no surfactant then) and subsequently intubated?
We took away their FRC
Grunting is a babies way of maintaining?
FRC
What are the 6 hazards of mechanical ventilation?
- Airway trauma
- Infection
- Pneumothorax
- PIE
- Impaired venous return
- IVH? (CPAP-inhibits venous return)
- Chronic Lung disease
The ETT is always smaller than?
So, if it is smaller, it has more________.
the trachea
Resistance
ETT’s _____ the lining of the trachea, even if just in/out for Surfactant
injure
In 1971, _____ was discovered, creating Neonatal ICU
CPAP
Name the 2 forms of oxygen toxicity
- O2 itself applied physically to the lung
~40% tolerated well
>70% is toxic to the lung - PaO2 (blood oxygen) is toxic to the organs inside (i.e. ROP)
The CORRECT PaO2 is _________
unknown
PaO2 measures?
The pressure in the dissolved plasma next to the RBC’s
O2 sat monitor is much more ________ measurement of O2 content than PaO2
exact
NIRS monitoring measures deep ______ saturation monitoring.
Why is this helpful?
Venous
To know the balance at oxygenation the end of the circulatory cycle (balance of checking account)
FRC is _____ compared to Vt
Huge
You have an FRC to allow for?
Oxygen exchange
CO2 diffuses ____ x’s faster than O2
22 x’s
O2 is _____ to diffuse.
Slow
Even during exhalation you use _____ to absorb oxygen.
FRC
FRC is a huge volume = ____cc/kg
25 cc/kg
Residual volume in adults is synonymous w/?
FRC
Oxygen =
FRC
Oxygenation is determined by ________, which is determined by _______, which is determined by ________.
FRC (residual volume)
MAP
PEEP
PEEP and _______ are synonyms
Oxygenation
CPAP and PEEP are physiologically ?
FRC
Blood is _____ color in the pulmonary artery and if the Alveoli is open, blood comes out _____ color.
If the Alveoli is collapsed, blood comes out _____
Blue
Pink
Blue
HMD= loss of?
FRC, you can not oxygenate
Too much FRC=
Overinflation
W/over-inflation you have what 2 things?
- Decreased Vt
- Decreased Venous Return
(can’t exhale, so increased CO2, can’t get blood back to chest so venous return goes down)
Surfactant deficiency is primarily a loss of?
FRC
With increased PEEP, you have a dramatic ________ in PaO2.
Increase
If you get too much PEEP, you will lose ____ which will increase ______
Vt
PaCO2
If a baby can maintain own FRC w/CPAP _____ them alone.
Leave
If a baby has increased need for ____ and are on CPAP, give them __________.
O2
Surfactant
There’s a relationship between _____ of Surfactant and lung _____.
Injury, so give Surfactant early if you need to give it.
W/CPAP and Surfactant use, try to avoid:
__________ & ____ _________
Atelectasis
Over-Distension
________ IS ventilation.
What determines this?
PaCO2
Alveolar Minute Ventilation (Inspired vol-phys. dead space x Rate/minute)
Alveolar Minute Ventilation =
Inspired Volume - Dead Space x Rate/Minute.
T/F: Alveolar MV is the same as MV reported on vent.
False.
Alveolar Minute Ventilation is what determines ______
CO2
Ventilation (PaCO2) depends on what 2 factors?
Tidal volume x Rate
A low PaCO2 <35 is a/w ___, why?
A PaCO2 <20 is a/w____, why?
CLD - maybe r/t overventilation
PVL-maybe r/t barotrauma or CO2 causing clamp down of blood flow to brain
There’s increase incidence of IVH if CO2’s over ____ in first few days of life.
70
What are the 3 things you need to know about the ventilator you are using?
- How breath is initiated (ie. pt triggered, time-cycled, etc)
- How gas flow is controlled (what the target is-via pressure or volume?)
- How the breath is terminated (change in flow-pressure or volume)
What does SIMV stand for?
Synchronized Intermittent Mandatory Ventilation
What does SIMV mean?
You pick a # of breaths to assist every minute (baby can still breathe over)
With PSV and A/C assist mode, how many pt breaths trigger the vent?
Every breath
The Mode defines the _________ sequence.
Breathing
Name the 3 types of Modes
- CMV-continuous mandatory ventilation (every breath is supported)
- IMV-Intermittent Mandatory ventilation (some breaths supported)
- CSV- Continuous Spontaneous Ventilation
Do time-cycled ventilators care what the baby is doing?
No, just gives a breath
Name the 3 modes of Patient Triggered ventilation
- SIMV
- PSV
- AC (SIPPV)
What do you get w/SIMV?
Fixed number of breaths supported
Uneven Minute Ventilation (Vt), high WOB
What do you get w/A/C?
Every breath is supported
Lack of control over rate (baby controls rate-or water in circuit can trigger)
Less intuitive, less familiar weaning strategy
What do you get w/PSV?
Stand-alone mode or in combination w/SIMV
Similar to A/C (every breath supported), has back-up IMV rate
Synchronizes end of breath, not just start
With PSV, baby controls ___ & ___.
What are 2 kinds of PSV?
Rate, IT
Pressure support alone or with Volume Guarantee
Adults say SIMV is very comfortable/uncomfortable. Do many providers use just SIMV?
Uncomfortable
No-used in combo w/PSV (the breaths that are not SIMV breaths)/VG, etc
Volume is dependent on what?
The compliance of the lung
Compliance is the change in ______ over the change in _______
volume
pressure
Pressure just tells you how ______ you’re pushing, it doesn’t tell you how much _____ you are giving
hard
gas
What is the problem w/volume ventilation?
What can cause problems?
What can you do to avoid problems?
The volume has to be totally, evenly distributed
Plugs in the lungs
Set a pressure limit so that the volume doesn’t go over a pressure that’s safe
PIP won’t hurt them unless…?
It generates too much Vt
The lung is destroyed by _______ not pressure.
Stretch (volutrauma)
What is the other type of trauma that is where the lung is collapsed (not enough PEEP) where it keeps opening and letting it collapse?
Atelecto-trauma
Most studies show fewer ______ days when _________ is targeted.
vent
Volume
An animal study showed that as few as ____ large breaths will give BPD
6
Use just enough pressure to see?
Chest rise
FRC is ____ whereas Vt is ____. Therefore, use ____ of PEEP and little _____.
Large, small
Lots, PIP
Adjust pressure/volume to deliver ____ cc/kg
4-7 cc/kg
Avoid these 2 things w/ventilation
- Hyperinflation
2. Underinflation
Hypocarbia is bad for: (2 things)
Lungs
Brain
Select ventilator Mode based on?
Whether baby is breathing or not breathing
With PSV, baby controls their own what?
IT
What is IT?
The time it takes to get the air in and the time it is held in (before coming out)
The stiffer the lung the more/less time it will take to get the air everywhere it needs to go?
Less
remember the example of ventilating the rock
All ventilators except which one use passive exhalation?
HFV
What is the typical IT?
0.3-0.4 sec
Time Constant is a marker of what?
how Stiff the lung is
___ time constants is the amount of time it will take to get 99% of the gas out of your lung.
5
What is the time constant for a healthy baby?
= about 0.12 seconds
A baby w/HMD will have a very ______ time constant.
Short
What is the equation for Time Constant?
Resistance (30 cm H2O/L/sec) x Compliance (L/cm H2O) = Time Constant
or Change in pressure over change in volume
VG results in what?
9 things
- Same/lower PIP
- More stable Vt
- Less hypocapnia
- Faster recovery from forced exhalation episodes
- Works better with A/C than SIMV (baby controls IT)
- Faster recovery from suctioning
- Pro-inflammatory cytokines decreased @ 5 mL/kg
- Faster weaning from mech ventilation
- Higher Vt needed w/advanced post-natal age
1% FiO2 increase will increase PaO2 by ___mmHg.
If the lung is ________ and ____ is adequate
6 (without pulmonary shunt)
Inflated, FRC
T/F: it’s easy to change PaO2 without a collapsed lung
True
Does FiO2 affect CO2?
No
Does FiO2 affect pH?
No
CPAP/PEEP increase will increase ______ dramatically. It’s the most important volume to maintain.
PaO2
CPAP/PEEP may make ______ higher and give you a metabolic _________ with increased/decreased venous return
CO2
Acidosis
Decreased
What is the most important parameter for PaCO2 that may recruit and improve PaO2 some as well?
Vt/PIP
Rate increase will ________ PaCO2.
If the baby is controlled by ventilator-direct correlation. If spontaneous breathing may have ___ effect.
Decrease
No
IT may increase _____ by having more FRC ________, no _____ effect. Beware ____ trauma
PaO2
Longer
PaCO2
Volutrauma
True/False: It’s not unusual w/CPAP to have a little respiratory and metabolic acidosis
True
A 10 increase in CO2 leads to ____ decrease in pH
0.1
