Respiratory Flashcards
review: Volume
amount of substance that occupies an enclosed area
- With gas -> we measure this in mL
review: Pressure
physical force exerted on an object/surface
- With Gas -> we measure this in cmH20
review: Compliance
an objects ability to undergo elastic deformation
Principles of oxygen delivery (4)
1) _______ is a ______
- (1)
2) ordered in ____/min or _____%
3) primary indication (1)
4) goal of therapy: (2)
1) Oxygen is a drug
- Both detrimental and beneficial effects
2) Ordered in liters per minute (L/min) flow or O2 percentage (FiO2)
3) Primary indication is hypoxemia
4) Goal of therapy:
Pao2 greater than 60 mm Hg
Sao2 greater than 90%
explain the Oxy-Hemoglobin dissociation curve
a graph that shows how oxygen binds to hemoglobin in the blood. It’s a vital tool for understanding how blood transports oxygen throughout the body
Oxygen Therapy: Methods of oxygen delivery (3)
1) _____ ______ systems:
- ____ L/min flow
2) _______ systems:
- (3) types
3) _______ systems: air/O2 blending system
- (3) types
1) Low-flow systems:
≤8 L/min flow (nasal cannula)
2) Reservoir systems:
- Simple face mask
- Partial rebreathing mask
- Non->rebreathing mask
3) High-flow systems – air/o2 blending system
- Air entrainment mask
- BiPap
- High Flow nasal cannula
Oxygen Therapy: Complications (3)
1) ?
- more than _____% FiO2 for more than ____ hours
2) ______ retention
- whos at risk?
3) _________ _________
- washes out the ________
- ____ replaces ______ in the alveoli
- ______ shrink and collapse
1) Oxygen toxicity:
More than 50% Fio2 for more than 24 hours
2) Carbon dioxide retention:
Patients with chronic obstructive pulmonary disease at risk
3) Absorption atelectasis:
Washes out the nitrogen
Oxygen replaces nitrogen in the alveoli
Alveoli shrink and collapse
tip:
CO2 Narcosis- High CO2 exists, the goal for breathing is to obtain oxygen.
Atmosphere is 70% nitro, which doesn’t enter the blood stream -> O2 does, and it can collapse alveoli if too much diffuses through the alveolar membrane and out of the air filled chambers.
Artificial Airways –(Avoiding Intubation) pharyngeal
what are the 2 types and indication?
how is it measured?
Pharyngeal airways:
1) Prevent tongue from obstructing upper airway
- Oropharyngeal airway
- Nasopharyngeal airway
2) Measure from lip to earlobe
tip:
- Seen in the ER, OR, PACU
- Requires intact respiratory center, ie. taking their own breaths.
INVASIVE MECHANICAL VENTILATION:
1) Indication: ?
- via _____ _______ ventilation
- ________ protection
2) types: (2)
3) ETT tubes: (2)
1) Facilitate transport of oxygen and carbon dioxide between atmosphere and alveoli
- Via Positive pressure ventilation
2) Airway protection
3) Types of ventilators
- Positive pressure
- Negative pressure (“Iron Lung”)
4) ETT Tubes:
- Oral ETT
- Nasal ETT
Endotracheal Tubes parts (6)
- Cuff provides seal
- Eventually erodes tracheal tissue
- Top attaches to the vent and ambubag (Ambubag should be readily available)
- ID the Cuff and the pilot balloon
- Vent tube and ETT suction (at tip)
- ETT with subglottal suction
INTUBATION
1) procedure: (4)
2) monitoring: (3)
1) Procedure
- Positioning
- Preoxygenation and ventilation (NRB or Ambubag)
——Suction on Standby
- IV Access to blunt gag reflex/sedate patient
—–Also will need steroids, Abx, IV fluid, pressors, continuous sedation, etc.
- Limit attempt to 30 seconds
Monitoring:
- Auscultation of breath sounds
- Disposable end-tidal CO2 detector
- Chest radiograph
tip:
Glide scopes are newer and better. - Artificial apppliances should be removed.
Airway Maintenance intubation
1) always secure _____ ______ with commercial tube holders
- allows for _______ of sites, tape can come lose and obstruct the ____ artery
- what does it do?
2) (1)
3) ____ mgmt
- _________ inflation/pressure
4) ________ - maintain proper technique
- keep the ______ patent
- avoid ________
- techniques changes based on: _______ vs. _________ suction systems
1) Always secure ETT tubes with commercial tube holders
- Alllows for rotation of sites, tape can come lose and obstruct the carotid artery,
-They keep the tube in place.
2) Humidification
3) Cuff management
- Cuff inflation/Cuff Pressure
4) Suctioning - maintain proper technique
- Keeping the airway patent
- Avoiding Complications
- Technique changes based on: Open (trach) versus closed (ETT/vent) suction systems
Suctioning Complications (4)
Hypoxemia
Bradycardia secondary to vagal nerve stimulation
Pain
Trauma
Airway trauma
Occurs when ett is too far and hits the carina, causing bleeding
Indications for Suctioning:
how often?
(6)
what do you want to assess?
Q8 hours or PRN
- for episodes of hypoxemia
- Course crackle over the trachea
- Elevated peak inspiratory pressure
- Decreased tidal volume
- Visible secretions
- Suspected aspiration
Assess the strength of cough
Contraindications of Suctioning: (6)
Mostly relative:
- Hypoxia
- Tissue trauma to tracheal mucosa
- Severe hypertension
- Elevated intracranial pressure
- Pulmonary bleeding
- Cardiac Dysrhythmias
Suctioning protocols (4)
1) Hyperoxygenation
Vents often have ‘suction’ buttons which provide 100% FiO2 for 15-30 seconds
2) Proper cuff inflation
3) Catheter external diameter size
4) No greater than 120 mm Hg suction
SUCTIONING: evidence states to avoid what?
Instillation of normal saline may contribute to hypoxemia and lower airway colonization
Sputum Samples: (2)
Nurses are responsible for obtaining sputum samples
Containers that connect to suction allow for direct aspiration of endotracheal colonization
ORAL CARE: (5)
1) Chlorhexidine or peroxide based cleansers are preferred
(Above toothbrush/tooth paste or saline based products)
2) Should be done every 3 hours and as needed
3) Oral secretions should be removed with Yankauer suction catheter or suction swab
4) Significantly reduces VAP (Ventilator associated pneumonia) and subsequent ‘ventilator days’
5) Other benefits include increased comfort and decreased nausea
Endotracheal Tubes (Other complications) (7)
Tube obstruction
Tube displacement
Sinusitis and nasal injury
Tracheoesophageal fistula
Mucosal lesions
- Move tube laterally each day
Laryngeal or tracheal stenosis
Cricoid abscess
Tracheostomy Tubes indications
- preferred for _______
- if patient intubated with ETT for more than ____ to ____ days (can be adjusted)
- what type of obstruction or trauma?
- __________ diseases (3)
Preferred for long-term intubation
If patient intubated with ETT for more than 7 to 10 days
- Can be stretched
Upper airway obstruction or trauma
Neuromuscular diseases
- ALS, MS, Myasthenia Gravis
Tracheostomy Tubes (cuff?)
Cuff only needs to be inflated when hooked to vent.
Communication on a ventilator (4)
Verbal
Nonverbal
Paper or tablet writing boards
Passy-Muir valve
tip:
RASS of negative 3.
-ALS guy with the tablet writing his wishes.
Positive Pressure Ventilation (3 types)
Pressure
Flow rate
Volume
Normal I:E ratio 1:2 or 3.
We breath via negative pressure. Our diaphragm moves down, our intercostals expand out and air is sucked into our lungs.
Invasive Mechanical Ventilation SETTING: what is it and numbers
1) _________ ________
- ____ to ____ (depending on patient condition)
2) _______ _______
- dependent on _____ _____ _____
3) ______ concentration (FiO2)
- _____ to ____%
4) ________ _______ ________
- ideally limit to ______
- >40cm may be seen with _______ (risking barotrauma)
5) _______ ____-_______ _______
- used to ________ ________ on ventilator
- to keep ______ open to decrease ______
- can cause ______ and _______
- ___cmH20 = standard ventilation initiation, maintains normal ______ volume
6) ________ ________
- adjusts for resistance of non-flexible tubing, supports tried diaphragm
- __ to __ cmH20
Ventilator settings:
1) Respiratory rate
(12-20 (depending on patient condition)
2) Tidal volume (Vt) -
- Dependent on IDEAL BODY WEIGHT
3) Oxygen concentration (Fio2) –
21-100%
4) Peak Inspiratory Pressure- (High P or PinsP)
- Ideally limit to 30cmH20,
- >40cm may be seen with ARDS (Risking barotrauma)
5) Positive end-expiratory pressure (PEEP)
- Used to improve oxygenation on ventilator
- To keep alveoli open to decrease shunt
- Can cause hypotension and pneumothorax
- 5cmH20= standard vent initiation, maintains normal residual volume
6) Pressure support (PS)
- Adjusts for resistance of non-flexible tubing, supports tired diaphragm
5-20cm H2O
tip:
Vt is based on body size.
-FiO2 typically by intervals of 5%.
-PEEP is the residual pressure left after
-High peep will compress the pulm vascularture and reduce left heart preload.
PS- assists for breaths through a narrower lumen.
Invasive Mechanical Ventilation MODES (4)
Volume Ventilation Modes
- Assist Control/CMV
- Synchronized Intermittent Mandatory Ventilation (SIMV)
Pressure Ventilation Modes
- Pressure Controlled Mode (PCV)
- Pressure ventilation mode (PSV)
Volume Ventilation Modes (2 types)
1) Ventilator modes (frequently used clinically)
- Assist-control (A/C) (also referred to as CMV
- Controlled mandatory volume)
2) Synchronized Intermittent mandatory ventilation (SIMV)
tip:
AC or CMV (Controlled mandatory volume)
volume mode 1: Assist Control (AC)/CMV
1) ______-_____ mode
2) ______ _______ is set
- if patient breathes _____ the ventilator will trigger to deliver _______ tidal volume
3) used when patient is ______ _____ or during _________
4) complications: (2)
1) Volume-control mode
2) Controlled rate is selected
- If patient breathes faster the ventilator will trigger to deliver full tidal volume (full-volume breath)
3) Used when patient is first intubated or during anesthesia (ie. During surgery)
4) Complications:
Air trapping, hyperventilation
tip:
Exhale loads of CO2. But hypoxia is less of a concern.
-Air trapping- The next breath occurs before the previous breath was totally expired.
volume mode 2: Synchronized Intermittent Mandatory Ventilation Mode (SIMV)
1) _____ and _____ ______ are preset
2) if patient wants to breathe ______ rate, but the ___ is varied and dependent on patient’s ________ effort
3) adding _______ ______ during spontaneous breaths can minimize risk of ______ ______
4) has been used as a method of ________
- by _______ the amount of _______ breaths
1) Rate and tidal volume are preset
2) If patient wants to breathe above rate, but the tidal volume is varied and dependent on patient’s spontaneous effort.
3) Adding pressure support during spontaneous breaths can minimize risk of increased work
4) Has been used as a method of weaning
- By decreasing the amount of mandatory breaths
Pressure Ventilation Modes (2)
Pressure-Controlled Ventilation Mode (PCV)
- Prevents elevated pressure in the lungs (Ideal is below 40 cmH2O)
Pressure Support Ventilation (PSV)
Principles of Pressure Modes (3)
Pressure will be set to allow oxygen to be delivered during inspiration.
Lung compliance will influence tidal volume
Weaning occurs by reducing the amount of pressure.
Pressure Mode 1: Pressure controlled ventilation (PCV)
- used to control _____ ______ in patients at risk of ___________, such as with ARDS and pulmonary fibrosis
- ________ is the goal (as opposed to volume with the previous 2 modes)
- also can extend __________ time to match _______ time in order to maintain _________ expansion
– normal I:E ratio is _____ or ______
– PCV can expand it from _____ to ______ (keeps alveoli open longer)
_______ changes with lung compliance
Used to control plateau pressures in patients at risk for barotrauma, such as with ARDS or Pulmonary Fibrosis
Pressure is the goal (As opposed to volume with the previous 2 modes)
IE
If pressure goal is 25cm H20
RR
VT- ???
Also can extends inspiratory time to match expiratory time in order to maintain alveolar expansion
- Normal inspiratory:expiratory ratio is 1:2 or 1:3
- PCV can expand it from 1:1 to 4:1 (Keeps alveoli open longer)
VT (Volume) will change with lung compliance
tip:
These patients almost always require sedation.
–We also don’t want patients at risk for baro trauma coughing, so sedation helps.
Baro- comes from the Greek word “Baros” which means pressure.
Pressure Mode 2: Pressure Support ventilation
1) ____ controlled breaths - _______ triggers breaths
2) applied for each ________ breath
3) _____ minimum ventilation -> relies on _______ ______
4) more ________ for some patients
Pressure support:
1) no controlled breaths - patient triggers breaths
2) applied for each triggered breath
3) no minimum ventilation -> relies of respiratory drive
4) more comfortable for some patients
Apart from changing the Mode to match the problem…
1) what settings can be changed? (4)
2) what settings are set by the patient (3)
1) Remember that settings can be changed:
a) FiO2 – Gives more O2
b) PEEP – Keeps alveoli open longer, opens collapsed ones, improves aeration
c) RR – Can be augmented to improve gas exchange
d) Pressure Support – Mostly used in weaning trials to overcome diaphragmatic weakness
2) Remember that some settings are set by the patients demands:
a) Vt – largely based upon ideal body weight and left alone
b) Peak inspiratory pressure (PinsP) – set at levels that would prevent trauma
c) RR – Can be augmented to improve gas exchange
NONINVASIVE Bilevel Positive-Pressure Ventilation Mode (BiPAP) (3)
used in patients with?
1) With airtight mask patient receives two different pressure support levels
- Inspiratory pressure support (IPAP) ie. 12 cmH20
- Expiratory pressure support (EPAP), same as CPAP or PEEP
Ie. 5cmH20.
Used in patients with worsening hypoventilation and hypercapnia to prevent intubation
Noninvasive Mechanical Ventilation
define: (1)
advantages (3)
disadvantage (4)
Define:
- Noninvasive (not intubated) method to administer positive-pressure ventilation
Advantages:
- Decreased frequency of HAP
- Increased comfort
- No sedation required
Disadvantages:
- Significant drying of oral mucosa
- Requires intact respiratory center
- Pt. must initiate breath
- Uncomfortable
Noninvasive Mechanical Ventilation: contraindications (6)
- Hemodynamic instability
- Dysrhythmias
- Apnea
- Uncooperativeness / Intolerance of mask
- Recent upper airway or esophageal surgery
- Inability to maintain patent airway, clear secretions, or properly fit mask
Other Non-Invasive Modes: CPAP (2)
1) CPAP (continuous positive airway pressure)
- Assist spontaneous breathing to improve oxygenation by increasing end-expiratory pressure
- One level of pressure support, often used with OSA
Ventilator Alarms: high or low alarm?
- Low exhaled volume
- Low inspiratory pressure
- Low exhaled minute volume
- Low PEEP/CPAP pressure
- High respiratory rate
- High pressure limit
- Low pressure oxygen inlet
- I:E ratio and temperature
- coughing
- mucous plug
- cuff leak
- anxiety
- pneumothorax
Troubleshooting ventilator alarms: if you can not find the problem, take patient off ventilator and manually bag the patient
- Low exhaled volume (low)
- Low inspiratory pressure (low)
- Low exhaled minute volume (low)
- Low PEEP/CPAP pressure (low)
- High respiratory rate (high)
- High pressure limit (high)
- Low pressure oxygen inlet (low)
- I:E ratio and temperature
- coughing (high)
- mucous plug (high)
- cuff leak (low)
- anxiety (high)
- pneumothorax (high)
key: obstructions = high
Care of the Intubated Patient
1) _________ assessment
- (1)
2) _____ _____ _____ assessment
3) _____ care
4) _____ changes
5) _______ _____ _____ at bedside for emergencies
6) monitor for _____ ____ ____
7) ______ patient and family about function of mechanical ventilation
Nursing management:
1) Pulmonary assessment
ANTERIOR AND POSTERIOR
2) Arterial blood gas assessment
3) Oral Care
4) Position changes
5) Manual rebreather mask at bedside for emergencies
6) Monitor for respiratory muscle fatigue
7) Educate patient (if appropriate, ie. Prior to surgery) and family about function of mechanical ventilation
Weaning (4)
- Intubation
- Positive pressure/ventilator therapy
- Weaning from ventilator support
- Extubation
weaning: Nursing Assessment
1) monitor for ______ ________ ________ (6)
2) _______ patient and family about function of mechanical ventilation
3) _______ at the bedside
1) Monitor for respiratory muscle fatigue
- Intercostal retractions
- Bradypnea
- Diaphoresis
- Tachycardia
- Change in mental status- tripoding/anxious to somnolent
- Lack of airflow
- Educate patient (if appropriate, ie. Prior to surgery) and family about function of mechanical ventilation
- Bag/Valve mask at the Bedside:
weaning: Readiness Criteria (10)
1) Cause of Respiratory failure has improved
2) Hemodynamically stable
- NSR or Tachycardia less than 140
- No shock states requiring vasopressor management
- No active ischemia or pulmonary edema
3) SaO2 >90% on FiO2: 40% or less, PEEP 5 cm
4) Chest x-ray reviewed for correctable factors and treated
5) Metabolic indicators (serum pH, major electrolytes) within normal limits
6) HCT>25%, Hgb >8 (7 is the newer trend)
7) Core temp 36-39 degree
8) Adequate management of pain/anxiety/agitation
9) No residual neuromuscular blockade
10) ABG values normalized or at patient’s baseline
They look good!*
weaning: Contraindications (6)
1) Cardiovascular instability
2) Open abdomen –OR- plans to return to Operating Room within 24 hours
3) Ongoing therapeutic hypothermia
4) Glasgow coma scale of less than 8
5) Any acute brain injury with invasive intracranial pressure monitoring
6) Patients who aren’t doing well…
- PaO2/FiO2 ratio less than 150
- still requiring high PEEP
- High FiO2,
- Minute Volume >15L per minute,
- RSBI (Rapid Shallow breathing index) over 105 (tachypnea with low minute volume)
- (RSBI is very technical- not necessary to memorize, but should make logical sense)
tip:
Respriations/ml/Breaht (ie. 25/.25 = 100 breaths/min/L)
PaO2/FiO2 Ratio
normal paO2
normal FiO2
pao2/fio2 ratio
PaO2/FiO2 ratio-
Normal: PaO2 ~100mmHg
Normal: FiO2 ~.21
PaO2/FiO2 ration: 100/.21 = 476
Poor ratio example:
PaO2 – 75
FiO2 - .50
Ratio – 75/.5 = 150.
SBT (Spontaneous Breathing Trials) – Techniques used:
*Pressure Support Ventilation- Gives the patients extra pressure to theoretically overcome the resistance of the ETT lumen
Weaning process: SBT (Spontaneous Breathing Trials)
1) if patient meets the discussed criteria -> transfer to ____
- start with _____ _____ support (this demands effort from the patient )
- observe for ____ to _____ minutes for s/sx of early failure (3)
- if patient fails tolerance criteria, _______ support as needed to achieve “rest” settings (goal: RR?)
- If the patient meets the discussed criteria…
- Transfer to PSV (Pressure support ventilation)
- Start with low-pressure support (This demands effort from the patient)
- Observe for 30 - 120 minutes for signs and symptoms of early failure:
- Tachypnea
- Low TV for patient size
- Tachycardia
If patient fails tolerance criteria, increase support as needed to achieve ‘rest’ settings. (Goal RR <20)
Failure to Wean (10)
Tolerance Criteria: if patient displays any of the following, return to rest settings.
Sustained RR > 35 breaths/per minute
SaO2 <90%
Tidal volume of 5 ml/kg or less
Sustained minute ventilation greater than 200 ml/kg/min
Evidence of respiratory or hemodynamic distress
- Labored breathing
- Increased anxiety diaphoresis or both
- Sustained HR > 20% higher or lower than baseline
- Systolic BP exceeding 18- mmHg or less than 90 mm Hg
Mental status alert and cooperative
Good cough and gag reflex and able to protect airway and clear secretions
NG tube/OGT feedings should be on hold for several hours prior to extubation
For long-term ventilated patient, success is defined as maintaining spontaneous ventilation for 24 hours.
EXTUBATION Preparation
Preparation for extubation begins on the day of intubation!
Extubation/Decannulation (15)
2 RN’s should be at bedside, along with the intensivist/MD in some cases
Instruct patient about the procedure
Hyperoxygenate with 100% FiO2
Suction trachea (then oral airway)
Deflate cuff
tell patient to breathe around ETT
Remove ETT
Administer oxygen – Nasal Cannula to Non-Rebreather
Monitor vital signs
Suction airway as needed
Monitor for respiratory distress
Observe for signs of airway occlusion
Encourage voice rest for 4 to 8 hours
Monitor ability to swallow and talk
At this time is is appropriate to:
Remove Foley catheter
Remove wrist restraints
Address removal of central line
Address removal of arterial monitoring catheters
NGT may or may not stay in – OGT must be removed with ETT
Keeping the patient off the ventilator (4)
Ensure oxygenation is adequate
- Hi Flow O2
- BiPap or CPAP
Secretion management via coughing, deep breathing and suctioning
Bronchodilators as needed
Sitting upright and mobilize if no contraindications
Post extubation Stridor
occurs in less than ___% of ventilated ICU patients
_____ _____ _____ ___ whistling
occurs more often in ______, ______, ______, _______
tx with _____ or ______
consider _________ if airway occlusion is imminent
Occurs in less than 10% of ventilated ICU patients
High pitched upper airway whistling
Occurs more often in older patients (80+), asthmatics, following aspiration and prolonged intubation (6+ Days)
Tx with steroids IV or nebulized epinephrine
Consider reintubation if airway occlusion is imminent
Self Extubation (4)
Case by case scenario
Oxygenate the patient with bag valve mask
Assess stability
Young patients who are weaned from sedation typically do better than geriatric counterparts
Assess for tracheal/vocal chord trauma
Overcoming barriers to ventilator weaning in the elderly (5)
- Sleep deprivation
- Imbalance of nutrition less than body requirements and risk for fluid volume imbalance
- Acute pain, anxiety and acute confusion
- Risk for constipation and diarrhea
- Risk for activity intolerance and impaired med mobility or - - impaired physical mobility
Acute Respiratory Failure - ARF (3)
What?
Pao2? Paco2? Ph?
- what’s depleted, retained?
____ assumed normal
Sudden and life-threatening deterioration in pulmonary gas exchange
Inadequate oxygenation with PaO2 <50mmHg. PaCO2>50 mmHg and pH<7.35
- O2 depletion, CO2 retention
Baseline ABGs are assumed normal
Acute Respiratory Failure: etiology (4)
Intrinsic Lung/Airway Disease
- Large Airway Obstruction
- Bronchial Diseases
- Parenchymal Diseases
- Cardiovascular Disease
Acute Respiratory Failure: Extrapulmonary Disorders (4)
- Disease of the Pleura and the Chest Wall
- Disorders of the Respiratory Muscles and Neuromuscular Junction
- Disorder of the Peripheral Nerves and Spinal Cord
- Disorder of the CNS
Acute Respiratory Failure: classified or combined with
1) classified as acute hypoxemic respiratory failure - needs ___, presents with:
(2)
2) classified as acute hypercapnic respiratory failure - needs to expel ______, presents:
(2)
3) combined acute hypoxemic and hypercapnic respiratory failure:
(1)
Classified as Acute Hypoxemic Respiratory Failure - Needs O2, presents with:
- Low PaO2
- Low PaCO2
Classified as Acute Hypercapnic Respiratory Failure – Needs to expel CO2, presents with:
- Marked elevation of carbon dioxide
- Preserved PaO2 levels
Combined Acute Hypoxemic and Hypercapnic respiratory failure
- Low PaO2, High PaCO2
Acute Respiratory Failure: Need of intubation(7)
- Dyspnea
- Depressed mental status or coma
- Severe respiratory distress
- Extremely low or agonal respiratory rate
- Obvious respiratory muscle fatigue
- Peripheral cyanosis
- Impending cardiopulmonary arrest
tip:
Lasicx, steroids, albuterol
Acute Respiratory Failure: Presentation (12)
Dyspnea
Cyanosis
Restlessness
Confusion
Anxiety
Delirium
Tachypnea
Tachycardia
Hypertension
Cardiac dysrhythmias
Tremor
Somnolence
Acute Respiratory Failure: diagnosis (3)
1) Uses arterial blood gas (ABG) analysis
- Pao2 less than 60 mm Hg (central cyanosis)
- Paco2 greater than 45 mm Hg (headache and dyspnea)
Confusion Somnolence
- In patients with chronically elevated Paco2 levels, the pH is considered (pH < 7.35)
Acute Respiratory Failure – Med mgmt
1) oxygenation (4)
- oxygen therapy is given to correct ______
- main o2 saturations at more than ______
- meets needs of?
- avoid ______ _______
2) ventulation: (5)
- what 2 types?
- initiate vent settings individualized for: (3), start on which mode?
3) acidosis (1)
- what is corrected and with what? (2)
what is not recommended even with pH less than 7.1
1) Oxygenation
- Oxygen therapy is given to correct hypoxemia
- Maintain oxygen saturation at more than 90%
- Meet needs of tissues
- Avoid oxygen toxicity
2) Ventilation
- Noninvasive ventilation
- Invasive mechanical ventilation
- Initial ventilator settings individualized for:
—–Underlying condition, patient size, and severity of respiratory failure
——Usually started on volume ventilation in the assist-control mode
3) Acidosis
- Respiratory acidosis is often corrected with effective oxygenation and ventilation
Sodium bicarbonate not recommended even with pH less than 7.1
Acute Respiratory Failure - PHARMACOLOGICS (6)
Bronchodilators: open airways (Albuterol)
- Anticholinergic agents: Ipratropium Bromide
Steroids: Reduce airway inflammation
Antibiotics: Usually empiric, broad spectrum
Sedatives: comfort, decrease work of breathing
Analgesics: pain control
Neuromuscular blockade: paralysis
- Facilitate optimal ventilation
- Decrease oxygen consumption
Acute Respiratory Failure - Nutrition (3)
- Avoid both malnutrition and overfeeding
- Enteral route is preferred
——Parenteral route = Infection risk - Initiate nutrition before day 3 on ventilator if well nourished and within 24 hours on ventilator if malnourished
Acute Respiratory Failure: complications (8)
Ischemic-anoxic encephalopathy
Cardiac dysrhythmias
Venous thromboembolism***
Gastrointestinal bleeding***
Artificial airway complications
Mechanical ventilation complications
Enteral and parenteral nutrition complications
- Keep feeding running to maintain patency
Peripheral arterial cannulation complications
tip:
GIB-
Acute Respiratory Failure- Nursing Mgmt (positioning - 4)
1) Positioning
- Position patient to best match V/Q. (Ventilation/Perfusion)
- Place least affected area of lung in a dependent position
——-Good lung down, bad lung up promotes drainage - Position at least every 2 hours
- Sitting up in chair -> early mobilization
TIP;
-Early mobility is KEY
Acute Respiratory Failure- Secretion mgmt (promote clearance by (5))
Promoting secretion clearance
- Systemic hydration
- Humidifying supplemental oxygen
- Suctioning
- Elevate the head of bed 30 to 45 degrees
- When extubated: deep breathing and use of incentive spirometer; coughing if secretions are present
Acute Respiratory Distress Syndrome – ARDS(SIRS of the Lungs)
________ injury d/t secondary effects (septic shock)
pulmonary manifestation of ______ _______ _____ - result of ?
characterized by (4)
- Pulmonary injury due to secondary effects–> ie. Septic Shock
- Pulmonary manifestation of multiple organ dysfunction syndrome-result of release of cellular and biochemical mediators
Characterized by:
**Diffuse pulmonary infiltrates on chest x-ray and hypoxemia
**Lung fibrosis unlike other disease
**alterations of lung epithelium and vascular tissue
**Increased pulmonary edema and impaired gas exchange.
TIP:
Cytokines and inflammatory changes secondary to infection cause pulmonary capillary pearmibilibity
Statistics Related to ARDS (mortality rate?, greatest risk for development (4))
Mortality rate of 40%+
Greatest risk for development:
- Sepsis
- Age older than 65 years
- Severe acute illness
- Preexisting chronic disorder
Diagnosis of ARDS requires 4 criteria
1) Acute onset
2) Bilateral infiltrates (on CXR)
3) PAOP of <18mmHg
–OR- no indication of left heart failure
4) PaO2/FiO2 Ratio of:
200-300 = Mild ARDS
100-200 – Moderate ARDS
<100 – Severe ARDS
Physiological Effects of ARDS (7)
1) Impaired ________ & _________
2) Resulting __________ ___________
3) Pulmonary __________ + Reduced _________ ________
4) Decreased ________ _________ and increase _________ __________
5) ________ _________ alveoli
6) ____________ collapse
7) ____________-constriction
1) Impaired Ventilation and Oxygenation
2) Resulting Pulmonary vasoconstriction
3) Pulmonary hypertension + Reduced blood flow
4) Decreased lung compliance and increase airway resistance
5) Fluid-filled alveoli
6) Alveolar collapse
7) Broncho-constriction
Multiple things limiting gas exchange
tip:
More pressure to get the same volume in the lungs.
Acute Resp Distress Direct injury (6)
Aspiration
Post Drowning
Infectious pneumonia
Lung contusions with trauma
Inhalation injury
Neurogenic pulmonary edema
Acute Resp Distress Indirect injury (9)
Sepsis
Burns
Trauma
Blood transfusion
Drug or alcohol overdose
Acute pancreatitis
Multiple fractures
Venous air embolism
Amniotic fluid embolism
ARDS exists in how many stages
3 stages
STAGE 1 – Early Exudative Stage (4)
First 7-10days result in diffuse alveolar damage (DAD)
Mediator-induced disruption of vascular bed
Increased interstitial and alveolar edema
- Increasingly permeable to proteins (much like vascular bed during septic shock)
Acute inflammation of the lung parenchyma
STAGE 2 – Fibroproliferative stage (4)
After the first week ->
Pulmonary Edema resolves
Cellular changes occur
Collagen and myofibroblasts cells used for healing, resulting in scar tissue
STAGE 3 – Fibrotic stage (4)
Fibrosis and Scarring of the lung fields
Decreases in PaO2, Increases in PaCO2
Multiorgan involvement, SIRS
Progressive lung fibrosis:
- Ventilation management difficulties
- Increased airway pressures
- Pneumothoraces
Physical Examination During ARDS (5)
Hemodynamically unstable -> Hypotension, tachycardia
Temp dysregulation -> Hyperthermia or hypothermia
Hypoxemia -> Tachypnea, dyspnea
Restlessness and agitation
- Lethargy ominous sign
Crackles
Arterial Gas Analysis VALI (3)
1) ______ ________
low PaO2 despite high FiO2 delivery
2) early - _______ _______
respiratory __________
3) __________ develops later
respiratory ___________
Refractory hypoxemia
- Low PaO2 despite high FiO2 delivery
Early—decreased PaCO2
- Respiratory alkalosis
Hypercapnia develops later.
- Respiratory acidosis
Development of Intrapulmonary Shunting:
Perfusion without ventilation is _____
ventilation without perfusion is______
combination of both in _____
- more than _____% ________ (no ventilation but blood flow also sucks)
P/F ratio:
- normal >300
- 200 = __-__% IPS
- 100 = >____ % IPS
Perfusion without ventilation (shunt)
Ventilation without perfusion (dead space)
Combination of both in ARDS
- ARDS more than 15% shunting (no ventilation but blood flow also sucks)
PaO2: FiO2 ratio
Normal > 300
200 associated with 15% to 20% intrapulmonary shunt
100 associated with more than 20% intrapulmonary shunt
tip:
Vasoconstriction will also lead to Dead space, meaning we ventilate areas where blood flow is nonexistent.
VALI: Ventilator Associated Lung Injury (2)
Also referred to as Barotrauma (Injury secondary to pressure)
Occurs due to low compliance of the lungs secondary to fibrosis
Ventilation Strategies to prevent VALI (6)
Permissive hypercapnia
- more concerned with oxygenation than CO2 retention
Pressure-controlled ventilation
- Lower Volume and Less trauma to the lungs, accommodates for reduced compliance
Inverse-ratio ventilation
- Longer inspiratory phase
Limit plateau pressures
Increase PEEP
- Keeps alveoli open
Novel vent modes
Treatment of ARDS (5 P’s)
5 P’s of ARDS therapy
1) Peeing
Diuresis to keep lungs less full of fluid
2) Positioning (Proning)
Allow consolidated areas to drain
3) Protective lung strategies
Expanded I:E ratio, PCV
4) Perfusion
Vasopressors for hemodynamic instability
5) Prednisone (Steroids)
Reduce/limit inflammation
Pharmacological Therapy (5)
1) Antibiotics, if indicated
Huge risk of Nosocomial infections
2) Bronchodilators and mucolytics
Albuterol, Xopenex
3) IV corticosteroids
Always taper off
4) Nitric oxide gas via mechanical ventilator
5) Sedation + Paralytics
Facilitates mechanical ventilation, decreases O2 demands
tip:
Adrenal insufficiency
Nutritional Support ards (4)
Enteral feeding benefits
Balanced caloric, protein, carbohydrate, and fat intake
- Ordered by Registered Dietician
Usually require 35 to 45 kcal/kg/d
- Most people require half of that to maintain weight
Theoretically - High carbohydrates avoided to prevent excess carbon dioxide production
Complications of ARDS (5)
Sepsis/SIRS
Barotrauma
- Pneumothorax
- Pneumomediastinum
VAP**
Immobility
DVT/PE
tip:
Pneumediatinum-
Mechanical Ventilation for ARDS: (what type of strategies?, includes (5))
RECAP
Lung protective ventilation strategies
- Limits ventilator-associated lung injury (VALI)
Includes:
- Low tidal volumes
- PEEP (Typically higher than 5)
- Limit plateau pressures to 30 cm H2O
- Pressure Controlled Ventilation
- Extended I:E ratioes
Acute Lung Injury/ARDS oxygen therapy (lowest level possible to maintain ______ greater than ____%)
fiO2 preferably less than ____%
PEEP: (4)
Lowest level possible to maintain saturation greater than 90%
Fio2 preferably less than 50%
Positive end-expiratory pressure (PEEP):
- Purpose is to open alveoli and decrease Fio2 levels
- Generally PEEP = 10 to 15 cm H2O
- If PEEP is too high, it overdistends alveoli
- If PEEP is too low, alveoli collapse during expiration
Positioning for vented patients (3)
1) Frequent position changes
Continuous lateral rotation
2) HOB elevated to prevent Vent Associated Pneumonia (VAP)
3) Prone positioning
May improve gas exchange
PRONING
description (2)
positioning (p/f ratio, criteria (2), problems (3), limitation (1))
Description
1) Match ventilation and perfusion through redistribution of oxygen and blood flow
2) Typically 12 hours on, 12 off
Prone positioning
1) Acute respiratory distress syndrome
——P/F ratio <150
2) Criteria
——Hemodynamic stability (?)
——Absence of abdominal surgery or spinal cord injury
3) PROBLEMS:
Pressure injuries, Airway occlusion, tube and line dislodgment
4) Limitations:
Mechanics of turning
Prone positioning Nursing management (6)
- Eye care/Oral care prior to prone
- Tubes and drains secure
- Intubation cart on standby
- Foley secured at foot of bed
- May need additional sedation
- Patient and family education
ABG Interpretation normal ranges PaO2, PaCO2, pH, HCO3
NORMAL RANGES
PaO2: 80-100 mmHg
PaCo2: 35-45 mmHg
pH: 7.35-7.45
HCO3: 22-26 mEq/L
Hypoxemia (1)
can improve PaO2 with: 4)
Hypoxemia-
PaO2 of less than 80mmHg.
Can Improve PaO2 with:
- More FiO2
—–Use as little as possible
- Higher PEEP
—–Risk of low BP and Barotrauma
- Longer I:E times
——Difficult for patients to tolerate
- Higher Volume/pressure (To a point)
——Increases Barotrauma risk
Arterial Blood Gases and Acid-Base Balance
Lungs are pivotal in acid-base balance
Hydrogen ions (H+) are formed from acids
pH is measure of the body’s hydrogen ion concentration and is inversely related
- Increase in hydrogen leads to decrease in pH
- Decrease in hydrogen leads to increase in pH
Normal arterial pH is 7.35 to 7.45
Small changes in pH lead to big physiological changes and even death
CO2 + H20 = H2CO3 = HCO3- + H+
Normal Arterial Blood Gas Values (Vary by Age)
pH: 7.35 to 7.45
- “Normal” decrease with age (7.26-7.43 for those >90)
PaCO2: 35 to 45 mm Hg
PaO2: 80 to 100 mm Hg
- Most oxygen is carried on the Hgb molecule as oxyhemoglobin so PaO2 is only one indicator of effective respirations
HCO3: 22-26mmHg
Balancing act…Sources of Acids
Glucose metabolism
Fat and protein metabolism
Anaerobic metabolism
Cell destruction
Balancing act…Sources of Bases (HCO3)
Breakdown of carbonic acid
Absorption of bicarb by intestines and reabsorption by kidneys
Intra cellular movement
Pancreatic production of bicarb
How to keep that balance
Buffers
Respiratory Mechanisms:
- Sensitive to CO2 levels
- Hyperventilation: “Blow it off” to bring pH up
- Hypoventilation: Retain CO2 to bring pH down
- Rapid response
Renal Mechanisms
- Slower to take effect
- Absorption or excretion of HCO3
- Formation of acids
- Formation of ammonium -> loss of hydrogen and drop in pH
Acidosis v. Alkalosis
Acidosis:
(a) Types:
Metabolic
Respiratory
Combined
(b) Manifestations:
- CNS depression
- Decrease in muscle tone
- Increased respiratory rate/depth
- Myocardial irritability
Alkalosis:
(a) Types:
Metabolic
Respiratory
Combined
(b)Manifestations:
- CNS excitement/seizures
- Tetany, cramps, twitches but weakness
- Myocardial irritability
How To Evaluate ABG’s
1) Evaluate the pH
2) Evaluate the PaCO2 (respiratory) and HCO3 (metabolic)
- Remember that the system will not overcompensate so the pH will represent the primary cause of the imbalance
Example: pH = 7.21 (acidosis)
PaCO2 = 60mm (higher, increased acid)
HCO3 = 26mEqL (normal)
What am I ???
3) Determine degree of compensation
For example, if there is a problem with the respiratory system, the renal system will try and move the HCO3 in the opposite direction in an attempt to bring the pH back into the normal range. Compensation can be partial or complete
Example: pH = 7.3 (acidosis)
PaCo2 = 60mm (high, increased acid)
HCO3 = 30mEqL (high, increased alkali)
What am I?
tip: ROME
