Airway/Ventilator Management Flashcards
Indications for Airway Management
Can not ventilate/oxygenate
Respiratory failure
Expected clinical course
Critical ABG Values
CRITICAL VALUES: pH <7.2, CO2 >55, PaO2 <60
Difficult Intubation Predictors:LEMON
Look
Evaluate 3-3-2
3 fingers in mouth
3 fingers between jaw and hyoid
2 fingers between hyoid and thyroid
Mallampati (I-IV)
Obstructions
Neck Mobility
Mallampati (Airway Grading)
- Mallampati I - Soft palate, uvula, anterior/posterior tonsillar pillars visible Tall, thin neck No difficulty
- Mallampati II - Tonsillar Pillars hidden by tongue
No difficulty - Mallampati III - Only the base of the uvula can be seen
Moderate difficulty - Mallampati IV - Uvula cannot be seen
Short, fat or muscular neck (difficult airway)
Difficult Intubation Predictors: HEAVEN
- Hypoxemia-O2 saturation less than 93% at the time of initial laryngoscopy
- Extremes of size-Patient less than or equal to 8 years of age or clinical obesity
- Anatomic challenges-Trauma, mass, swelling, foreign body, or other structural abnormality limiting view
- Vomit/blood/fluid-Clinically significant fluid in the pharynx or hypopharynx
- Exsanguination/anemia-Suspected anemia that could potentially accelerate the rate of decompensation during RSI apneic period
- Neck mobility issues
How do you preform ramping for airway management?
Ear to sternal notch positioning
* Improved upper airway patency
* Decreased work of breathing
* Prolonged safe apnea period
What is External Laryngeal Manipulation (ELM)?
Provider performing laryngoscopy brings cords into view, then the airway assistant maintains positioning
Current standard of practice if airway manipulation is needed
Fun fact: Overtook the Sellick’s Maneuver: BURP: Backward, Upward, Rightward Pressure
ETT Cuff Pressure
Between 20-30 mmHg
25 mmHg is standard
7 P’s for RSI
- Preparation Make sure equipment is serviceable
- Preoxygenate 3-5 minutes, passive oxygenation via NC 10-15+ LPM
- Pretreatment LOAD medications if required
- Paralysis with induction Induction agent, paralytic, and pain control
- Protect and position Ear to sternal notch, ramping, pad behind shoulders for pediatrics
- Placement with proof Visual confirmation, capnography, chest x-ray
- Post intubation management Maintain sedation and pain control, oxygenation, etc
LOAD (RSI Pretreatment)
- Lidocaine blunts the cough reflex preventing ICP increase
- Opiates blunts the pain response
- Atropine for infants prevents reflexive bradycardia in infants <1 y/o
- Defasiculating Dose 1/10 dose of Rocuronium or Vecuronium
- Lidcocaine,Atrpopine and Defasicualing dose are old medicine and have been disproven for pretreatment before RSI
- USE Push dose presures epi/Neoepi
What is Tidal Volume (Vt)? What is the normal ventilator setting ?
- How much air the patient breathes in a normal breath
- 4-8 cc/kg IBW (ideal body weight)
Note: Excessive tidal volume can cause Ventilator-Induced Lung Injury (VILI)
Inspiratory Reserve Volume (IRV)
The amount of air that can be forcefully inhaled in addition to a normal tidal volume breath
Expiratory Reserve Volume (ERV)
The amount of air that can be forcefully exhaled after a normal tidal volume breath
Vital Capacity (VC)
Tidal Volume + Inspiratory Reserve Volume + Expiratory Reserve Volume
Residual Volume (RV)
The amount of air left in the respiratory tract following forceful exhalation
Total Lung Capacity (TLC)
Inspiratory Reserve Volume + Tidal Volume + Expiratory Reserve Volume + Residual Volume
Dead Space
The surfaces of the airway that are not involved in gaseous exchange
Gas exchange ONLY occurs in the alveoli
Dead Space Formula = 2ml/kg
Chemoreceptors: Central Vs Peripheral
Central
Located in the medulla/pons
Response is driven by CO2 and H+ levels in cerebral spinal fluid (CSF) This is a slowly responding system
Peripheral
Located in the aortic arch/carotid bodies
Response is driven by O2, CO2, H+
Your body’s “pulse ox
Abnormal Respiratory Patterns: Apneustic
Deep, gasping inspiration with a pause at full inspiration followed by a brief, insufficient release
Associated with decerebrate posturing
Abnormal Respiratory Patterns:Ataxic
Complete irregularity of breathing, with irregular pauses and increasing periods of apnea
Caused by damage to the medulla secondary to trauma or stroke
Very poor prognosis
Abnormal Respiratory Patterns: Biot’s
Groups of quick, shallow inspirations followed by regular or irregular periods of apnea
Caused by damage to the medulla by stroke (CVA) or trauma, or pressure on the medulla secondary to brainstem herniation
Abnormal Respiratory Patterns: Cheyne-Stokes
Progressively deeper and sometimes faster breathing, followed by a gradual decrease that results in atemporary apnea
Associated with decorticate posturing (Cushing’s ∆, brainstem herniation)
Abnormal Respiratory Patterns: Kussmaul’s
Respirations gradually become deep, labored and gasping
Associated with DKA
Gold Standard for oxygenation
Pulse oximetry (SpO2)
Gold Standard for ventilation
Waveform capnography (ETCO2)
What is the #1 cause of iatrogenic death in the U.S.?
VAP-Ventilator acquired pneumonia
Hypoxic Respiratory Failure
Inability to diffuse O2 -ARDS, Pneumonia, CHF
Lab Value ABG low pO2 < 60 mmHg
Treatment– ↑ O2 concentration (FiO2) and PEEP
Hypercarbic Respiratory Failure
Inability to remove CO2-Damage to pons or upper medulla
Stroke & trauma
Lab Value respiratory acidosis EtCO2 > 45 mmHg
Treatment- ↑ tidal volume (Pplat), then ↑ rate
Double Minute Volume (Ve), normal 4-8 L/min
What is the normal ventilator setting for Rate (F)?
12-20/min
How many times a minute the patient is breathing (respiratory rate)
What is Minute Volume (Ve)? What is minute volume?
How much air is breathed by the patient in one minute.
Rate x Tital volume = Ve
Normal Ve is 4-8 L/min
Inspiratory: Expiratory Ratio (I:E)
1:2
The ratio of inspiration vs. expiration
Fraction of Inspired Oxygen (FIO2)
0.21 to 1.0
Allows for very precise delivery of oxygen concentrations
21% - 100% O2 concentration
Measuring oxygen with liters per minute (lpm) is much less accurate
Positive End Expiratory Pressure (PEEP)
0-20 cm H2O
PEEP is what keeps the alveoli open so that oxygen can diffuse
Adequate PEEP, increased FRC, and driving pressure helps prevent atelectasis (alveolar collapse), by reopening and stabilizing collapsed or unstable alveoli
Ventilator Delivery Methods and Explain
* Volume mode- A preset tidal volume is delivered
Once tidal volume is delivered the exhalation begins
Volumes are consistent breath to breathe
Pressures are continuously monitored
* Pressure Control-A preset inspiratory pressure is delivered
Once pressure is achieved the exhalation begins
Volumes are dynamic from breath to breath
Volumes need to be continuously monitored
Peak Inspiratory Pressure (PIP)
Amount if resistance to overcome the ventilator circuit, any appliances, the ETT, and the main
airways
<35 cmH2O
Plateau Pressure (Pplat)
This is a measurement of the pressure applied
during positive pressure ventilations to the small
airways and alveoli
Represents the static end inspiratory recoil pressure of the respiratory system, lung and chest
wall respectively
Measured during an inspiratory pause (i-hold) while on mechanical ventilation
<30 cmH20
Ventilator Modes: Controlled Mandatory Ventilation (CMV)
All breaths are triggered, limited, and cycled by the ventilator
Patient has NO ability to initiate their own breaths
Ventilator Modes: Assist-Control Ventilation (AC)
Ventilator supports every breath, whether it’s initiated by the patient or the ventilator Full tidal volume (Vt) regardless of respiratory effort or drive
Note: Preferred mode for patients with respiratory distress, Mode can leads to “breath stacking” or “auto-PEEP” Risk of Ventilator-Induced Lung Injury (VILI)
Ventilator Modes: Synchronized Intermittent Mandatory Ventilation (SIMV)
Assisted mechanical ventilation synchronized with the patient’s breathing,The ventilator senses the patient taking a breath, then delivers a breath.If the patient fails to take a breath the ventilator will provide a mechanical breath
Note:Preferred for patients with an intact respiratory drive
Ventilator Modes: Pressure Support Ventilation (PSV)
Pressure support makes it easier for the patient to overcome the resistance of the ET tube and is
often used during weaning because it reduces the work of breathing
“Supports” or provides pressure during inspiration to decrease patient’s overall work of
breathing
Patient determines tidal volumes, rate (minute volume)
Note:Requires consistent ventilatory effort by the patient
Continuous Positive Airway Pressure (CPAP)
The use of continuous positive pressure to maintain a continuous level of PEEP
CPAP uses mild air pressure to keep an airway open
Bi-Level Continuous Positive Airway Pressure (BPAP)
Uses alternating levels of PEEP to maintain oxygenation through pressure support during
inhalation and exhalation, commonly used in pneumonia, COPD, asthma
The term BiPAP
TM refers to a specific manufacturer, not a vent setting
Ventilator Alarms-DOPES
Dislodged low pressure alarm
Obstructed high pressure alarm
Pneumothorax high pressure alarm
Equipment machine failure, dead batteries, etc.
Stacked breaths high pressure alarm
Ventilator Alarms-DOPES
Ventilator Alarms-Low Pressure
Patient disconnection from machine (most common cause)
Chest tube leaks
Circuit leaks
Airway leaks
Note- Start from the ventilator and go to the patient.
Ventilator Alarms-High Pressure
Kinked line (most common cause)
Coughing
Secretions or mucus in the airway
Patient biting the tube
Reduced lung compliance (Pneumothorax, ARDS)
Increased airway resistance
Note- Start from the patient then got to the ventilator.
Ventilator Dyssynchrony
Caused by:
Respiratory demands not being met
Inadequate pain control
Inadequate sedation
Effects on the patient: Increased RR,O2 demand, BP,HR and ICP
Treatment:Administer analgesia and sedation and adjusted Settings as needed
Ventilator Dyssynchrony
Caused by:
Respiratory demands not being met
Inadequate pain control
Inadequate sedation
Effects on the patient: Increased RR,O2 demand, BP,HR and ICP
Treatment: Administer analgesia and sedation and adjusted Settings as needed
V/Q Ratio
Ratio of alveolar ventilation and blood travelling through the capillaries
V/Q Formula = alveolar ventilation/cardiac output
Normal V/Q = (4 L/min)/(5 L/min)
V/Q = 0.8
How do you find a V/Q mismatch
V/Q Scanning
A nuclear medicine study used to evaluate the circulation of air and blood within a patient’s lungs
The ventilation portion evaluates the ability of air to reach all parts of the lungs
The perfusion portion evaluates how well blood circulates throughout all parts of the lungs
Used to help determine presence of a pulmonary embolism
Other diagnostics include Well’s criteria, CT Pulmonary Angiogram (CTPA)
