1
Q
What is ventilation ?
A
the movement of gases in and out of the alveoli
- Intake issue: oversedation, stroke, obstruction, sleep apnea
2
Q
What is diffusion ?
A
movement of O2/CO2 molecules from higher to lower pressure
- Exchange issues: pulmonary edema, pneumonia, ARDS (lungs become stiff and fibrotic)
3
Q
What is perfusion ?
A
movement of oxygenated blood to the tissues
- Cardiac issue: MI, shock or CHF
- heart isn’t contracting like it should
4
Q
What controls the respiratory drive ?
A
the medulla and pons
5
Q
What is the difference between a COPD pt and a normal pt’s respiratory drive ?
A
- COPD: decreased O2 level stimulates the pt to breath
- Normal Pt: elevated CO2 level stimulates the pt to breath
6
Q
Why does a COPD pt not react to elevated CO2 ?
A
their body is already used to elevated CO2 levels
- decreased O2 is what drives them instead
7
Q
What is compliance ?
A
distensibility or elasticity
- do they open easily or are they stiff and take tons of effort to open lungs
8
Q
What does increased compliance mean ?
A
the lungs easily open up but don’t recoil back to normal (causes air trapping)
- COPD
9
Q
What does decreased compliance mean ?
A
hard to open up due to being stiff
- ARDS
10
Q
What are some causes of airway narrowing ?
A
- asthma
- bronchial spasms
- mucus build up
- ET tube placement
11
Q
What are some S&S of respiratory distress ?
A
- increased RR
- accessory muscle use
- SOB
- confusion
- anxiety
- tripod position
- decreased SpO2
Late signs: - cyanosis
- nasal flaring
- decreased RR
12
Q
What causes crackles ?
A
fluid in the airways or the snapping open of collapsed airways
- during inspiration
- produced in the smaller airways
- pt can cough and clear these sounds
13
Q
What causes rhonchi ?
A
an obstruction in the airway caused by secretions like mucus, fluid, etc.
- heard during expiration
- in larger airways like main bronchus
14
Q
What causes wheezes ?
A
narrowing of airways of bronchioles cause by obstruction
15
Q
What causes stridor ?
A
narrowing of the upper respiratory tract like trachea & larynx
- Ex.) allergic reaction (laryngeal edema)
16
Q
What causes Biot/Ataxic breathing patterns ?
A
neurological issues like brainstem problems
17
Q
What are Cheyne-Stokes breaths ?
A
varying periods of increasing depth interspersed with apnea
18
Q
What are Kussmaul’s breaths ?
A
rapid, deep, and labored
19
Q
What is Biot breathing ?
A
irregularly interspersed periods of apnea in a disorganized sequence of breaths
20
Q
What is Ataxic breathing ?
A
significant disorganization with irregular and varying depths of respiration
21
Q
What are the normal values in ABGs ?
A
- pH: 7.35-7.45
- PaCO2: 35-45
- HCO3: 22-26
- PaO2: 80-100
- SaO2: 92-100%
22
Q
What ABG values represent ventilation ?
A
- pH
- PaCO2
- HCO3
- Base Excess: -2 to +2
23
Q
What ABG values represent oxygenation ?
A
- PaO2
- SaO2
24
Q
What PaO2 levels would you intubate and need a NC/nonrebreather ?
A
- intubation: 60 or below
- NC or partial nonrebreather: 60-80
25
What is Refractory Hypoxemia ?
when supplemental O2 doesn't improve O2 levels
26
What does the oxyhemoglobin dissociation curve describe ?
a graph that shows how easily Hgb picks up O2 in the lungs and lets it go in the tissue
- When O2 are high the Hgb grabs O2 easily and with low O2 the Hgb releases O2 where it's needed
27
What do shifts to the left mean on the oxyhemoglobin dissociation curve ?
keeps the O2 bound to the Hgb when tissues don't need as much
- the Hgb doesn't release O2 as easily (holds on tight)
- Ex.) hypothermic, many PRBCs, alkalosis
28
What do shifts to the right mean on the oxyhemoglobin dissociation curve ?
Hgb lets go of O2 easily which makes it easier to deliver O2 to the tissues that need it
- Ex.) acidosis, hyperthermia, anemia, low CO
29
What is the difference between PaO2 and SaO2 ?
- PaO2: oxygen dissolved in plasma
- SaO2: oxygen bound to the hemoglobin
- for small changes in SaO2 you have big changes in PaO2
30
How far is the ET tube placed ?
3-4 cm above the carina (where trachea splits into Lt and Rt)
- may go into the Rt stem so you'll need to pull it back
31
What are the steps in the Rapid Sequence Intubation (RSI) ?
1. preparation
2. preoxygenation
3. pretreatment
4. paralysis
5. positioning
6. placement of ETT
7. postintubation management
32
What occurs in the preparation stage of RSI ?
gather all the equipment needed
- call RT
- get ambu bag
- get ventilator and ventilator box
33
What occurs in the preoxygenation stage of RSI ?
preoxygenate pt with non rebreather mask or ambu bag with 100% O2
- minimum 3-5 mins
34
What occurs in the pretreatment stage of RSI ?
give the patient the necessary meds to decrease the physiological response to intubation
- give pain meds 1st (Fentanyl)
- give sedative 2nd (versed)
35
What occurs in the paralysis stage of RSI ?
give paralytic to paralyze muscles and control spontaneous breathing with pt's on mechanical ventilation
- most end up in -ium
- Ex.) Cisatracurium
36
What occurs in the positioning stage of RSI ?
put pt in the snuff position
- neck flexed with nose pointed up to open the airway and the head back
37
What occurs in the placement of ETT stage of RSI ?
the placement of ETT tube is 3-4 cm above the carina
- each attempt limited to 30 secs to prevent hypoxemia
- initial verification with end-tidal CO2 and confirm placement with: chest-x-ray
- Assess: BILATERAL chest rise and fall, auscultation for lungs sounds BILATERALLY
38
What occurs in the postintubation management stage of RSI ?
- ensure chest x-ray
- pt order for sedative drip (propofo)
- make sure restraints applied
- OG tube inserted to decompress stomach to avoid aspiration
- mark level of insertion and secure to pts face
39
What does respiratory rate indicate ?
the number of breaths ventilator delivers in a minute
- 6 to 20 breaths/min
- controls CO2 levels
- determined by WOB, PCO2, an pH
- increased RR means increased WOB
40
What does tidal volume indicate ?
volume of gas delivered to the patient during each ventilator breath
- 6 to 10 mL/kg per pt's ideal body weight or 4-8 mL/kg in ARDS
- how big of breath pt is taking
- calculate using pt's weight
41
Why do we want a ARDS pt to have a smaller tidal volume ?
if the tidal volume is high it can cause the lungs/alveoli to pop due to stiffness of lungs
- 4 to 8 mL/Kg is goal
42
What does fraction of inspired oxygen (FiO2) indicate ?
O2 concentration delivered to patient
- 0.21 to 1.00 (21%-100%)
- adjusted to maintain PaO2>60
- anything over 50% is considered high
- controls PaO2
- can change dial to increase or decrease O2 level
43
What does positive end-expiratory pressure (PEEP) indicate ?
positive pressure applied at end of expiration of ventilator breaths
- 5 to 20 cm H20
- helps to hold airways open and improve gas exchange during expiration
- high end of normal/cut off is 10-12
- also helps PaO2
- can decrease CVP and CO and increase ICP
44
Why may someone be using PEEP ?
used when the pt is exhaling air trapped in the alveoli at the end of expiration which can help improve gas exchange
45
What does pressure support (PS) indicate ?
positive pressure used in conjugation with patient's current inspiratory efforts
- 5 to 10 cm H20
- spontaneous inspiration (pt triggered breaths)
- can be used to wean pt off ventilator or combo with other modes
46
What does I:E ratio indicate ?
ration of duration of inspiration to duration of expiration
- 1:2
- expiratory phase tends to be 2x long as inspiratory
47
What does pressure limit (PL) indicate ?
regulates the maximal pressure the ventilator can generate to deliver tV
- when limit is reached the ventilator terminates breath and spills undelivered volume into the atmosphere
- 10 to 20 cm H2O above PIP
48
Why may a patient have a pressure limit ?
if their lungs are really stiff because they are at risk for their lungs popping
49
What 2 values control CO2 levels ?
RR and tV
50
What 2 values control PaO2 levels ?
FiO2 & PEEP
51
What is Ppeak ?
the highest amount of pressure needed to open up the lungs during inspiration
- indicates how compliant the lungs are
- >30 means lungs aren't very compliant and are hard to open up
52
How do you calculate minute ventilation (Mve) ?
tV X pt's RR
53
What is volume mode on a ventilator mean ?
always sets the tidal volume
- for each breath they will get volume of 450 regardless of the pressure
- doesn't care about pressure so it can pop lungs
54
What is pressure mode on a ventilator mean ?
always sets pressure limits
- pays attention to the force needed to open lungs and once you hit limit the vent stops giving the breath
- you can measure tidal volume but NOT control it
55
What is the Volume Assist/Control ventilator (V-A/C) ?
has preset RR and tV
- all breaths regardless if vent or patient initiated with receive preset tV
- works well for pt's with normal respiratory drive but too weak to perform the WOB
- will CONTROL ALL BREATHS and force tidal volume
56
What pt's would and wouldn't do well for V-A/C mode ?
- Work well: pt’s with healthy lungs/respiratory drive (going to surgery and not worried about popping) but can’t do the WOB due to weakness (anesthesia effects)
- Won't work: COPD (don't want to force and air easily comes in but not out) and stiff lungs like ARDS pt's (easily causes pneumonia)
57
What are the 2 volume ventilation modes ?
- Volume Assist/Control (V-A/C)
- Volume Intermittent Mandatory Ventilation (V-IMV)
58
What settings are used in V-A/C ?
- tV
- RR
- PEEP
- FiO2
59
What is the Volume Intermittent Mandatory Ventilation (V-IMV) ?
has preset RR and preset tV for ventilator-initiated breaths only
- tV of patient/spontaneous breaths is patient dependent
- pt can do spontaneous breaths in between ventilator set RR
- works for patient with spontaneous breaths but aids in those you don't
- provides pressure support for spontaneous breaths
60
What type of patient is V-IMV/SIMV good for ?
- pt who gets intubated and then extubated and status keeps changing
- wanting to wean pt off ventilator
61
What does positive pressure mean ?
way of helping patient breathe by pushing air into the lungs
62
What ventilator settings are used in V-IMV ?
- tV
- RR
- PEEP
- FiO2
- P.S (for spontaneous breaths)
63
What are the pressure ventilator types ?
CPAP, pressure support, BiPAP, & P-A/C
64
What is Continuous Positive Airway Pressure (CPAP) ?
(+) pressure applied during spontaneous expiration
- spontaneous expiration breathing mode where the patient controls the rate, inspiratory flow and tidal volume
- patient breaths on their own so no ventilator breaths
65
What settings are used with CPAP ?
PEEP &FiO2
66
What patients may benefit from CPAP ?
ARDS
- causes stiff lungs and hard to open lungs up
- keeping PEEP makes it easier for next breath to go in and aids in PaO2 increase
67
What patients would we not use pressure support/CPAP/BiPAP ?
if they can't breath using a only a mask
- stroke: can't keep RR up
- nausea: will aspirate
- patients with tons of secretions: aspiration risk
68
What settings are used in pressure support ?
FiO2 & P.S
69
What is bi-level positive airway pressure (BiPAP) ?
works during inspiration and expiration
- helps push air into the lungs and decrease WOB during inspiration
- keeps airways open and prevents collapse and improves oxygenation during expiration
- uses PEEP, FiO2 & P.S
70
What is pressure assist control (P-A/C) ?
has pressure limit set during BOTH mandatory and spontaneous inspiration
- Set RR and pressure limit @ 10-20 cm H20
- protective mode since doesn't let you overinflate the lungs
- controls ALL BREATHS even pt controlled ones
- once limit hits it stops
- pays attention to compliance
71
Which patient population would work will with P-A/C ?
ARDS, cystic fibrosis, COVID, bad pneumonia
72
What settings are used in P-A/C ?
- RR
- PEEP
- FiO2
- P.L
73
What are hydrid ventilator modes ?
uses both pressure and volume control
- very common in ICU pt's
- will deliver tV at the lowest possible pressure possible
- once pressure limit exceeds the alarm will go off
74
What settings are used in hybrid modes ?
- tV
- RR
- PEEP
- FiO2
- P.L
75
What are some reasons for low volume/low pressure alarms ?
low exhaled volume or leak in system
- cuff leak
- tube disconnection
- patient disconnection
- tube of out position
- low inspiratory pressure
76
What are some reasons for high pressure alarms ?
- secretions in airway
- mucous plug
- kinks in ET tubing
- biting ET tube
- coughing/gagging
- dyssynchrony
- anxiety, fear, pain
- increased airway resistance/decreased lung compliance
77
How do you remove a mucous plug from a ETT ?
manually ambu bag the pt to break up the plug and suction
78
What are examples of complications caused by positive pressure ventilation ?
- tension pneumonia
- pneumothorax
- ventilator associated pneumonia
- atelectasis
79
What causes ventilator associated pneumonia ?
oral secretions sliding down to the upper airway and pile/sit upon the cuff and then the secretions slide down the cuff and get into the lungs
80
What are some S&S of displacement of ETT and prevention ?
- S&S of respiratory distress
- want to see bilateral chest rise and fall
- prevention: securement device
81
How do we prevent unplanned extubation ?
- prevention: ensure pt is restrained, adequately sedated, on plenty of analgesics
- have ambu bag with face mask (if on ventilator) nearby in case of self-extubation
- if tolerate well may not need restraints
82
How do we prevent tracheal injuries ?
no oral intubation for more then 2 weeks
- if needed for longer we will move onto trach
- cuff on ET tube causes the injury
- Peds: can go months before consider trach
83
What causes barotrauma ?
excessive pressure within the alveoli
- too much PEEP
- need to weigh the risks/benefits of high PEEP
84
What causes volutrauma ?
excessive volume in the alveoli
- too large tV
85
What are some S&S of volutrauma ?
- high PIP and mean airway pressures
- decreased lung sounds (on the side effected)
- tracheal shift
- hypoxemia
- tachycardia
- hypotension
86
What can volutrauma cause ?
alveoli to burst:
- subcutaneous emphysema
- pneumothorax
- tension pneumothorax
- pneumopericardium (air in pericardial sac)
87
What causes oxygen toxicity ?
prolonged exposure to high concentrations of oxygen
- can lead to decreased compliance
88
What are some S&S of oxygen toxicity ?
- substernal chest pain present with deep breathing
- dry cough
- pleuritic pain
89
What puts you at risk for oxygen toxicity ?
>50% FiO2 for 24 hrs
- goal is to keep FiO2 <50
90
What are some interventions to decrease risk of ventilator associated pneumonia (VAP) and why ?
- HOB 30-45 degrees: avoids aspiration
- subglottic suctioning: q6 hrs to get rid of secretions that piled up
- prophylaxis DVT & peptic ulcer: heparin & protonix
- spontaneous awakening trial (SAT): evaluates need for mechanical ventilation
- spontaneous breathing trial
- q2hrs oral hygiene: with CHG brush
- reposition ETT (Lt/Rt) daily or q4hrs
91
What is a spontaneous awakening trial (SAT) ?
"sedation vacation"
- daily interruption of sedation to evaluate the patient's need for continues sedation and mechanical ventilation
- if pt can tolerate >4 hrs then it can be discontinued
92
What are some contraindications to a spontaneous awakening trial (SAT) ?
- hemodynamic instability
- increased ICP
- ongoing agitation
- seizures
- alcohol withdrawal
- use of neuromuscular blocking agents
93
How is dysphagia caused by mechanical ventilation ?
the swallowing reflex atrophies due to decrease usage
- can't have anything to drink/eat after being extubated because of this atrophy which poses an aspiration risk
94
What cardiovascular complications occur due to mechanical ventilation ?
- CO & CVP decrease due to an increase in intrathoracic pressure which puts pressure on the vessels which decreases the venous return to the Rt side of heart
- decreased CO due to impairment in venous return which decreases preload (CVP)
95
What gastrointestinal complications occur due to mechanical ventilation ?
stressful to be on a ventilator so:
- can cause stress ulcers: use pantoprazole for prophylaxis
- increased nutritional needs (within 24 hrs of being intubated)
- high protein, calorie, and fat supplementation
96
What assessments are used for sedatives, analgesics, and paralytics ?
- Sedation: RASS
- Analgesics: CPOT
- Paralytic: TOF
97
What are examples of sedatives ?
- Propofol/Diprivan: drops BP
- Lorazepam/Ativan: excreted soly thru kidneys
- Midazolam/Versed:
- Dexmedetomidine/Precedex: can induce severe bradycardia
98
What are examples of analgesics ?
fentanyl & morphine
99
What are examples of paralytics ?
- Cisatracurium/Nimbex
- Vecuronium
100
What are the goal ranges for RASS, CPOT, and TOF ?
- RASS: -2 to +1 (will titrate to this)
- CPOT: < 3
- TOF: 2 out of 4
101
What is train of four (TOF) ?
Deliver 4 mild shocks are delivered in a row to the ulnar nerve to test the level of paralysis
- if paralyzed we want thumb twitch 2 out of 4 times
- normal is 4/4 twitches
- before start infusion of paralytic need to establish baseline (# of electric shock (mV) to see strength of shock needed to get reaction w/o sedative)
102
What criteria must be met for sedation to be turned off and awakening trial can begin ?
- underlying cause of respiratory failure resolving (if due to pneumonia then improvement in WBCs)
- hemodynamically stable
- Hgb> 8
- PEEP <5-8
- SaO2 > 90% & FiO2 <40%
- minute ventilation (mVe): < 15 L/min
103
When can you start a spontaneous breathing trial ?
- if patient passes the spontaneous awakening trial
- lasts 30-120 mins
- use modes that don't control RR
- pressure support, CPAP, or BiPAP
104
What occurs in a spontaneous breathing trial ?
patient is still intubated but they have to do their own breathing thru the ET tubs
- if they pass you can extubate them to a NC
105
What criteria must be met for a successful spontaneous breathing trial ?
- RR <35
- HR<120
- SBP >90 <180
- SaO2 >90% & FiO2 <40%
- tV > 4 mL/kg
- CO2 does not increase by more than 10
- no agitation, diaphoresis, or increased WOB
106
What does a (+) response look like with TOF ?
thumb twitches and adducts across the palm
- the thumb moves medially across the palm
- goal is to give the lowest dose possible of the paralytic to avoid prolonged weakness after eventual discontinuation of med
