Initial Settings Flashcards
what are the goals for choosing a type of ventilator and mode
airway mgmt
ventilation
oxygenation disturbance
non-invasive accomplished in 3 ways
NPV
CPAP
NPPV
where is negative pressure ventilators most often used
used in home and for long term
where does negative pressure ventilation pressure go
across chest wall
what must be stable in patients who use negative pressure ventilation
compliance and resistance , airway protection, ability to swallow
why is negative pressure ventilation not good for acute exacerbation of COPD
they can have changes with compliance and resistance
is negative pressure ventilation good for obstructive sleep apnea
no
what are some negative pressure ventilation disadvantages
pt access difficult may cause tank shock no spontaneous breathing no control hot and noisy
where do set the rate for negative pressure ventilaiton
set 5-10 below patients rate
where do you increase negative pressure till
till patient can’t talk
why is it good that a patient can’t talk when ventilating with negative pressure
means there is enough flow to the patient
what is the max pressure that can be achieved with negative pressure ventilaiton
35
what do you use to measure volume with negative pressure ventilation
spirometer
how do you increase volume with negative pressure ventialton
increase pressure or I time
what are some hazards of an iron lung
abdominal pooling
large and in the way for nursing
what is a benefit to using a chest curaiss
eliminates abdominal pooling
why are chest cuirasses difficult to use
difficult to maintain a seal
where does a chest cuirass apply pressure
applies negative pressure to thorax
what are the indications for NIV/NPPV
pts with acute on chronic respiratory failure who require short term ventilation
terminally ill pts
pts who tolerate nasal/mask long term
pts with acute resp failure
when is bipap mostly used
patients with CHF
when do you not use NPPV/NIV
severe acidosis
shock bp <90 mmhg
uncontrolled arrhythmias
upper airway obstruction/trauma
NPPV for chronic RF
chest wall deformities
neuromuscular disorders
central alveolar hypoventilation
COPD
what does NPPV cause
gastric distention, skin pressure sores, facial pain, dry nose, eye irritation, poor sleep, and discomfort
what is the overall goal of ventilation
support the minute ventilation in order to meet the oxygen need
what is full ventilatory support
all work is coming from the machine, even if pt is doing something it isn’t good enough to not be in FVS
what is partial ventilatory support
weaning, lower amount that machine does
what mode ventilates pts with disease more - pressure or volume
pressure
when is volume mood good for
iatrogenic hyperventilation in control head injuries
why do you want alveolar hyperventilation in control head injuries
guaranteed a minute ventilation
how does pressure mode help improve distribution of ventiliation
descending flow pattern
which mode of ventilation has more control over minute ventilation - pressure or volume
volume
lower compliance or higher resistance results in higher what pressures
peak and plateau pressures
when is peak pressure higher with what type of flow
constant flow
when is peak pressure lower with what type of flow
descending flow
what do high volumes do to peak/plat pressures
make them high
what is the goal of volume ventilation
goal of a minute ventilation that matches the patients metabolic needs
how do you find tidal volume with F and MV
MV=F x VT
how do you determine total cycle time
TCT = 60/F
how do you calculate flow from VT and I Time
flow = vt/ti (l/sec)
how do you estimate body surface area
by the dubois BSA chart
what can calculate vt and f
radford nomogram
where should you keep platue pressure at to prevent alveolar overdistension
<30 cmh2o
what is tubing compliance usually
3-4 ml/cmh2o
how do you calculate delivered VT
tubing factor x peak pressure = what is lost in tubing and then subtract out peep
how much deadspace does an HME add
20-90mL
how much deadspace is there b/w the wye and endotracheal tube
75 mL
what does driving force equal
pressure gradient
in normal lungs what selection do you make for rates/vt
large VT, and slow frequency with flow to meet demand
in lungs with COPD what selection do you make for rates/vt
high compliance and raw - moderate VT and low frequency and high flow to meet demand
in lungs with restrictive disease what selection do you make for rates/vt
smaller VT, high frequency, and slower flow
flow and flow patterns have what relationship with i time
inverse relationship
what happens if you have high flow
high flow shortens I time and increase PAP
what happens if you have slower flow
slower flow increases I time and decreases PAP but may lead to air trapping and shorter E time
what are the 3 types of flow patterns
constant
sine
descending
what is sine
it gives better distribution than constant, PAW and PEAK equal to constant peak higher when raw is high
descending
occurs naturally in pressure ventilation, peak press is lower, paw is higher, vd is lower, oxygenation is better
which is more important high paw or pip
high paw
what happens to MAP with descending flow
it increases
what happens to MAP with ascending flow
decreases
what happens to PIP with ascending flow
increases
what happens to PIP with descending flow
decreases
what does descending flow improve
gas distribution and arterial oxygenation
what are the goals of PSV
increase VT
decrease RR
decrease WOB associated with artificial airway
what muscle is an indicator of adequate PSV
sternocleidomastoid muscle
what should you set PSV with lung dx
8-14
what should you set psv without lung dx
about 5
