Mechanical Ventilation Flashcards
what are some reasons why a patient would need a mechanical vent?
- oxygenate the blood for the pt with poor ventilation
- control respirations during surgery (sedated, paralyzed)
- rest resp muscles
name indications for using mech vent
decr PaO2 incr PaCO2 peristent acidosis treat resp failure compromised airway
what are the 2 major types of ventillators
negative
positive
is negative pressure still used
no- almost never
what are the different types of positive pressure ventilators?
volume cycled pressure cycled flow cycled time cycled non-invasive (mask)
what are the different modes of the vent?
AC (Assist Control) IMV(Intermittent Mandatory Vent) SIMV (Synchronized Int Mand Vent) CPAP (Constant Positive Airway Pressure) PS (pressure support) PEEP (Positive End Expiratory Pressure)
what is assist control mode?
we control everything
what is CPAP mode
patient controls their own breath and we support them
Name the MD orders r/t the Vent?
Mode- AC/ CPAP RR TV FiO2 PEEP
what is tidal volume
volume in ml that is inhaled in a single breath
what is a normal tidal volume
400-500 mL
what is the RR usually set to
12-14 bpm
what is FiO2
the %age of oxygen that is delivered through the machine
what is the normal FiO2 that is ordered
30-100
what is the goal of PEEP
to keep alveolar inflated and help exchange of gases
what is a healthy persons natural PEEP
3
what will a vents PEEP be set to
5-15
what is the absolute highest PEEP you can set PEEP to
20
how does a negative pressure ventillator work?
exerts negative pressure on the external chest
what is the modern negative ventillator called
chest cuirass
what is the old negative ventillator called
iron lung
how does a positive pressure ventillator work
exerts positive pressure on the airway- pushes air in and forces alveoli to expand during inspiration
through the use of positive pressure ventillators, does expiration occur passively or actively?
passively
what is required for the use of a positive pressure ventillator?
advanced airway- ETT, trach
how are positive pressured ventillators classified?
by the method of ending the inspiratory phase of respiration
name the different positive pressured ventillators
volume cycled
pressured cycled
high frequency cycled
non-invasive positive positive pressure ventilation (mask)
how do volume cycled vents work?
breath ends when set volume has been delivered
how do pressure cycled vents work?
breath ends when set amt of pressure has been delivered
how do high freq cycled vents work?
delivers set # of breaths per minute
what is the most common positive pressure ventillator
volume cycled
what are the major limitations of the pressure cycled vent?
- vol delivered is varied
- vol delivered depends on pts airway resistance and compliance
- alterations in tv can compromise ventilation
t/f- high freq oscillatory vent is considred last option vent
true
how many breaths does the high freq oscillatory vent deliver?
180-900 bpm
does the high freq oscillatory vent deliver a high or low tv and why?
very low- protect lungs from pressure injury
does the high freq oscillatory vent deliver high or low airway pressure and how much?
high- 40 mL
for what conditions is the high freq oscillatory vent used for
atelectasis
ARDS
What are some indications for Non-invasive Positive pressure ventilation
resp failure
pulmonary edema
chf
sleep related disorder
name the different non-invasive positve pressure vents
continuous positive airway pressure (CPAP)
bi-level positive airway pressure (bi-pap)
during CPAP, what kind of support do you get?
pressure support during inhalation, peep support, and exhalation support
during bi-pap, what kind of support do you get?
inspiration and exhalation support
how does AC mode work?
full ventilatory support
preset tv and RR
every breath (machine or pt) will receive a preset vol
IN AC mode, what happens if the pt initiates their own breath?
the machine will deliver the preset volume and assist the breath
how does IMV mode work?
- combo of machine and pt breathing
- machine breaths @ preset time and vol
- spontaneous breaths not assisted- neither by time nor vol- pt must use own muscles
what is a disadvantage of using IMV mode?
pt often expends energy fighting the machine
how does SIMV mode work?
- machine delivers preset tv and RR
- pt can initiate their own breath
- pt breath still not assisted
- pt breath causes machine to sense and will not initiate a machine breathe in opposition of the pts breath
what is a disadvantage of the SIMV mode
still does not assist the pt with their own initiated breath
what is an advantage of SIMV mode?
decreases the need for the pt to fight the machine
is the iMV mode used often
no- never
is the SIMV mode used often
no- almost never
how does pressure support ventilation work?
machine applies a pressure to the airway throughout the patient triggered breath
what are the advantages of using PSV
decr the resistance in the ETT and machine tubing
decr the work of breathing for the patient
PS is reduced as pts strength increases
what is PEEP
positive pressure maintained by the ventilator at the end of expiration
what are some advantages of PEEP
increases functional residual capacity
opens collapsed alveoli
improves oxygenation and allows for a lower FiO2
how does CPAP work?
positive pressure applied throughout the resp cycle to a spontaneously breathing patient
what are some of the advantages of CPAP
promotes alveolar and airway stability
what are some requirements that must be in place when using CPAP?
no timed cycle
no assist
pt must have own RR
how is CPAP admin?
ETT, trach, mask
when can CPAP not be used and why?
if a pt is apneic bc they do not have a regular breathing pattern
assessment of the patient on a vent
systematic assessment of all body systems focused resp assessment oxygen status comfort coping and emotional needs communication
name the components of a focused respiratory assessment
capillary refill abg O2 Sat perfusion status neuro status bil breath sounds
initial vent settings
TV- 6-12 ml/kg FiO2- 100---> reduce quickly as pt O2 sat increases RR- 12-16 BPM Mode- AC---> CPAP, PSV PEEP- 5-15 cm H2O
what are some problems a/s with use of the vent?
alterations in cardiac function
barotrauma
pulmonary function
sepsis
how does PEEP affect the body?
it makes the blood returning to the right atrium work harder and decreases the CO
what is barotrauma
localized trauma to the alveoli
what can barotrauma result in?
bleeding
what can cause barotrauma
pressure and TV too high
invasive air being pushed in
sepsis starts _______ and spreads________
locally, systemically
what interventions enhance gas exchange?
monitor abg's monitor for indicators of hypoxia follow trends auscultate lung sounds frequently judicious use of analgesics monitor fluid balance- I/O's interdisciplinary approach
what interventions promote effective airway clearance
assess lung sounds q 2-4 h suctioning cpt position changes promote early mobility humidification- warm and wet meds
what meds promote effective airway clearance
bronchodilators
abx
nebulizers
how often must tubes and vents be checked?
at least every shift
cuff should be managed and assess for what?
secretions seal proper inflation not too low not too hard
what else should be checked on the trach and ETT?
the suction port and subglottic secretions
HOW DO YOU PREVENT VAP???!!!
daily interruption of sedation assess daily readiness to extubate dvt and pud prophylaxis daily oral care w/ chlorhexidine oral care with peroxide q 2-4 hrs hob above 30 HAND WASHING
the process of weaning is _______
gradual
def weaning
process of gradual withdrawal from dependance upon ventilator
successful weaning is a _________ process
collaborative
what is the criteria for weaning
stable mental status
good and consistent resp assessment
no use of vasopressors
no need for blood
how are pts prepped for weaning
hob elevated not sedated o2 sat is good TV good positioning airway is cleared RR good and regular
what method is used for weaning
CPAP trial
def extubation
the discontinuation of an artificial airway
name indications of extubation of original placement
obstruction protection of the airway suctioning ventilatory failure hypoxemia
list the guidelines for extubation r/t adequate pulmonary mechanical function
RR < 25 BPM spontaneous TV < 5 ml/kg Inspiratory force of at least -20 cm H2O vital capacity at least 10 ml/kg ABG: PaO2 >60 mm Hg w/ FiO2 < 0.5 PaCO2 in the normal range for that pt pH > 7.35
def chronic ventilation
when long term ventilation is necessary to sustain life
name some conditions in which chronic ventilation may be needed
stroke
SCI
neuromucular disorders
chronic illnesses that require repeated tx in ICU
def terminal wean
when all life sustaining support is turned off
do you need a md order for a terminal wean
yes
what else do you need for a terminal wean
patient wish
living will
proxy
what is Pulmonary Rehab
a broad program that helps improve the well being of ppl who have chronic breathing problems
who does the PR Program benefit?
ppl who have: COPD Sarcoidosis Idiopathic Pulmonary Fibrosis Cystic Fibrosis
Need Lung Surgery- Before and After
what interventions does the PR program do?
exercise training nutrition counseling education on ling disease or ur disease and how to mng energy conserving techniques breathing strategies psychological couseling/group support
