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Airway ManagementPart 1
EMS Professions
Temple College
Topics for Discussion
Airway Maintenance Objectives Airway Anatomy & Physiology Review Causes of Respiratory Difficulty & Distress Assessing Respiratory Function Methods of Airway Management Methods of Ventilatory Management Common Out-of-Hospital Equipment Utilized Advanced Methods of Airway Management and
Ventilation Risks to the Paramedic
Objectives of Airway Management & Ventilation
Primary Objective: Ensure optimal ventilation
Deliver oxygen to bloodEliminate carbon dioxide (C02) from body
Definitions What is airway management? How does it differ from spontaneous,
manual or assisted ventilations?
Objectives of Airway Management & Ventilation
Why is this so important? Brain death occurs rapidly; other tissue
follows EMS providers can reduce additional
injury/disease by good airway, ventilation techniques
EMS providers often neglect BLS airway, ventilation skills
Airway Anatomy Review
Upper Airway AnatomyLower Airway AnatomyLung Capacities/VolumesPediatric Airway Differences
Anatomy of the Upper Airway
Upper Airway Anatomy
Functions: warm, filter, humidify airNasal cavity and nasopharynx
Formed by union of facial bones Nasal floor towards ear not eye Lined with mucous membranes, cilia Tissues are delicate, vascular Adenoids
Lymph tissue - filters bacteriaCommonly infected
Upper Airway Anatomy
Oral cavity and oropharynx Teeth Tongue
Attached at mandible, hyoid boneMost common airway obstruction cause
PalateRoof of mouthSeparates oropharynx and nasopharynxAnterior= hard palate; Posterior= soft palate
Upper Airway Anatomy
Oral cavity and oropharynx Tonsils
Lymph tissue - filters bacteriaCommonly infected
EpiglottisLeaf-like structureCloses during swallowingPrevents aspiration
Vallecula“Pocket” formed by base of tongue, epiglottis
Upper Airway Anatomy
Upper Airway Anatomy
Sinuses cavities formed by
cranial bones act as tributaries
for fluid to, from eustachian tubes, tear ducts
trap bacteria, commonly infected
Upper Airway Anatomy
Larynx Attached to hyoid bone
Horseshoe shaped boneSupports trachea
Thyroid cartilageLargest laryngeal cartilageShield-shapedCartilage anteriorly, smooth muscle posteriorly“Adam’s Apple”Glottic opening directly behind
Upper Airway Anatomy
Larynx Glottic opening
Adult airway’s narrowest pointDependent on muscle toneContains vocal bands
Arytenoid cartilagePosterior attachment of vocal bands
Upper Airway Anatomy
Larynx Cricoid ring
First tracheal ringCompletely cartilaginousCompression (Sellick maneuver) occludes
esophagus
Cricothyroid membraneMembrane between cricoid, thyroid cartilagesSite for surgical, needle airway placement
Upper Airway Anatomy
Larynx and Trachea Associated Structures
Thyroid gland• below cricoid cartilage• lies across trachea, up both sides
Carotid arteries• branch across, lie closely alongside trachea
Jugular veins• branch across and lie close to trachea
Upper Airway Anatomy
Upper Airway Anatomy
Pediatric vs Adult Upper Airway Larger tongue in comparison to size of
mouth Floppy epiglottis Delicate teeth, gums More superior larynx Funnel shaped larynx due to undeveloped
cricoid cartilage Narrowest point at cricoid ring before ~8
years old
Upper Airway Anatomy
From: CPEM, TRIPP, 1998
Upper Airway Anatomy
Glottic Opening
Lower Airway Anatomy
Function Exchange O2 , CO2 with blood
Location From glottic opening to alveolar-
capillary membrane
Lower Airway Anatomy
Trachea Bifurcates (divides) at carina Right, left mainstem bronchi Right mainstem bronchus shorter,
straighter Lined with mucous cells, beta-2
receptors
Lower Airway Anatomy
Bronchi Branch into secondary, tertiary bronchi
that branch into bronchiolesBronchioles
No cartilage in walls Small smooth muscle tubes Branch into alveolar ducts that end at
alveolar sacs
Lower Airway Anatomy
Alveoli “Balloon-like” clusters Site of gas exchange Lined with surfactant
Decreases surface tension eases expansion
surfactant atelectasis (focal collapse of alveoli0
Lower Airway Anatomy
Lungs Right lung = 3 lobes; Left lung = 2 lobes Parenchymal tissue Pleura
VisceralParietalPleural space
Lower Airway Anatomy
Lower Airway Anatomy
Occlusion of bronchioles Smooth muscle
contraction (bronchospasm
Mucus plugs Inflammatory
edema Foreign bodies
Lung Volumes/Capacities
Typical adult male total lung capacity = 6 liters
Tidal Volume (VT) Gas volume inhaled or exhaled during
single ventilatory cycle Usually 5-7 cc/kg (typically 500 cc)
Lung Volumes/Capacities
Dead Space Air (VD) Air unavailable for gas exchange
Lung Volumes/Capacities
Dead Space Air (VD) Anatomic dead space (~150cc)
TracheaBronchi
Physiologic dead spaceShunting
Pathological dead spaceFormed by factors like disease or obstructionExamples: COPD
Lung Volumes/Capacities
Alveolar Air (alveolar volume) [VA] Air reaching alveoli for gas exchange Usually 350 cc
Lung Volumes/Capacities
Minute Volume [Vmin](minute ventilation) Amount of gas moved in, out of respiratory
tract per minute Tidal volume X RR
Alveolar Minute Volume Amount of gas moved in, out of alveoli per
minute (tidal volume - dead space volume) X RR
Lung Volumes/Capacities
Functional Reserve Capacity (FRC) After optimal inspiration, amount of air
that can be forced from lungs in single exhalation
Lung Volumes/Capacities
Inspiratory Reserve Volume (IRV) Amount of gas that can be inspired in
addition to tidal volumeExpiratory Reserve Volume (ERV)
Amount of gas that can be expired after passive (relaxed) expiration
Lung Volumes/Capacities
Ventilation
Movement of air in, out of lungsControl via:
Respiratory center in medulla Apneustic, pneumotaxic centers in pons
Ventilation Inspiration
Stimulus from respiratory center of brain (medulla) Transmitted via phrenic nerve to diaphragm, spinal
cord/intercostal nerves to intercostal muscles Diaphragm contracts, flattens Intercostal muscles contract; ribs move up and out Air spaces in lungs stretch, increase in size intrapulmonic pressure (pressure gradient) Air flows into airways, alveoli inflate until pressure
equalizes
Ventilation
Expiration Stretch receptors in lungs signal respiratory
center via vagus nerve to inhibit inspiration (Hering-Breuer reflex)
Natural elasticity of lungs pulls diaphragm, chest wall to resting position
Pulmonary air spaces decrease in size Intrapulmonary pressure rises Air flows out until pressure equalizes
Ventilation
Ventilation
Ventilation
Respiratory Drive Chemoreceptors in medulla Stimulated PaCO2 or pH
PaCO2 is normal neuroregulatory control of ventilations
Hypoxic Drive Chemoreceptors in aortic arch, carotid bodies Stimulated by PaO2
Back-up regulatory control
Ventilation
Other stimulants or depressants Body temp: fever; hypothermia Drugs/meds: increase or decrease Pain: increases, but occasionally
decreases Emotion: increases Acidosis: increases Sleep: decreases
Gas Measurements
Total Pressure Combined pressure of all atmospheric
gases 760 mm Hg (torr) at sea level
Partial Pressure Pressure exerted by each gas in a
mixture
Gas Measurements
Partial Pressures Atmospheric
Nitrogen 597.0 torr (78.62%); Oxygen 159.0 torr (20.84%); Carbon Dioxide 0.3 torr (0.04%); Water 3.7 torr (0.5%)
Alveolar Nitrogen 569.0 torr (74.9%); Oxygen 104.0
torr (13.7%); CO2 40.0 torr (5.2%); Water 47.0 torr (6.2%)
Respiration
Ventilation vs. RespirationExchange of gases between living
organism, environmentExternal Respiration
Exchange between lungs, blood cellsInternal Respiration
Exchange between blood cells, tissues
Respiration
How are O2, CO2 transported? Diffusion
Movement of gases along a concentration gradient
Gases dissolve in water, pass through alveolar membrane from areas of higher concentration to areas of lower concentration
FiO2
% oxygen in inspired air expressed as a decimal FiO2 of room air = 0.21
Respiration
Blood Oxygen Content dissolved O2 crosses capillary membrane,
binds to Hgb of RBC Transport = O2 bound to hemoglobin
(97%) or dissolved in plasma O2 Saturation
% of hemoglobin saturated with oxygen (usually carries >96% of total)
O2 content divided by O2 carrying capacity
Respiration
Oxygen saturation affected by: Low Hgb (anemia, hemorrhage) Inadequate oxygen availability at alveoli Poor diffusion across pulmonary membrane
(pneumonia, pulmonary edema, COPD) Ventilation/Perfusion (V/Q) mismatch
Blood moves past collapsed alveoli (shunting)Alveoli intact but blood flow impaired
Respiration
Blood Carbon Dioxide Content Byproduct of work (cellular respiration) Transported as bicarbonate (HCO3
- ion) 20-30% bound to hemoglobin Pressure gradient causes CO2 diffusion
into alveoli from blood Increased level = hypercarbia
Respiration
Alveoli PO2 100 & PCO2 40
PO2 40 & PCO2 46 - Pulmonary circulation - PO2 100 & PCO2 40
Heart
PO2 40 & PCO2 46 - Systemic circulation - PO2 100 & PCO2 40
Tissue cell PO2 <40 & PCO2 >46
Inspired Air: PO2 160 & PCO2 0.3
OxygenatedDeoxygenated
Diagnostic Testing
Pulse OximetryPeak Expiratory Flow TestingPulmonary Function TestingEnd-Tidal CO2 MonitoringLaboratory Testing of Blood
Arterial Venous
Causes of Hypoxemia
Lower partial pressure of atmospheric O2
Inadequate hemoglobin level in bloodHemoglobin bound by other gas (CO) pulmonary alveolar membrane distanceReduced surface area for gas exchangeDecreased mechanical effort
Causes of Airway/Ventilatory Compromise
Airway Obstruction Tongue Foreign body obstruction Anaphylaxis/angioedema Upper airway burn Maxillofacial/laryngeal/trachebronchial
trauma Epiglottitis Croup
Obstruction
Tongue Most common cause Snoring respirations Corrected by positioning
Foreign Body
Partial or FullSymptoms include
Choking Gagging Stridor Dyspnea Aphonia Dysphonia
Laryngeal Spasm
Spasmatic closure of vocal cordsFrequently caused by
Overly aggressive technique during intubation
Immediately upon extubation
Laryngeal Edema
Causes Angioedema Anaphylaxis Upper airway burns Epiglottitis Croup Trauma
Aspiration
Significantly increases mortality Obstructs Airway Destroys bronchial tissue Introduces pathogens Decreases ability to ventilate Frequently occult
Obstructive Airway Disease
Obstructive airway disease Asthma Emphysema Chronic Bronchitis
Gas Exchange Surface
Pulmonary edema Left-sided heart failure Toxic inhalation Near drowning
PneumoniaPulmonary embolism
Blood clots Amniotic fluid Fat embolism
Causes of Airway/Ventilatory Compromise
Thoracic Bellows Chest trauma
Fib fracturesFlail chestPneumothoraxHemothoraxSucking chest woundDiaphragmatic hernia
Causes of Airway/Ventilatory Compromise
Thoracic Bellows Pleural effusion Spinal cord trauma Morbid obesity (Pickwickian Syndrome) Neurological/neuromuscular disease
PoliomyelitisMyasthenia gravisMuscular dystrophyGullian-Barre syndrome
Causes of Airway/Ventilatory Compromise
Control System Head trauma Cerebrovascular accident Depressant drug toxicity
NarcoticsSedative-HypnoticsEthanol
Assessment of Airway/Ventilatory Compromise
Respiratory Distress/Dyspnea = Possible Life Threat
Assess/Manage SimultaneouslyPriorities
Airway Breathing Circulation Disability
Assessment of Airway/Ventilatory Compromise
Airway Listen to patient talk/breathe Noisy breathing = Obstructed breathing But, all obstructed breathing is not noisy Adventitious sounds
Snoring = TongueStridor = “Tight” Upper Airway
Assessment of Airway/Ventilatory Compromise
Breathing Look
Symmetry of Chest ExpansionSigns of Increased EffortSkin Color
ListenMouth and NoseLung Fields
FeelMouth and NoseSymmetry of Expansion
Assessment of Airway/Ventilatory Compromise
Breathing Tachypnea Bradypnea Signs of distress
Nasal flaringTracheal tuggingRetractionsAccessory muscle useTripod positioning
Cyanosis
Assessment of Airway/Ventilatory Compromise
Circulation Don’t let respiratory failure distract
you!!! Tachycardia = Early hypoxia in adults Bradycardia = Early hypoxia in infants,
children; Late hypoxia in adults
Assessment of Airway/Ventilatory Compromise
Disability Restlessness, anxiety, combativeness =
hypoxia until proven otherwise Drowsiness, lethargy = hypercarbia
until proven otherwise When the fighting stops, a patient isn’t
always getting better
Assessment of Airway/Ventilatory Compromise
Focused Exam Respiratory Patterns
Cheyne-Stokes = diffuse cerebral cortex injury
Kussmaul = acidosisBiot’s (cluster) = increased ICP; pons, upper
medulla injuryCentral Neurogenic Hyperventilation =
increased ICP; mid-brain injuryAgonal = brain anoxia
Assessment of Airway/Ventilatory Compromise
Focused Exam Neck
Trachea mid-line?Jugular vein distension?Subcutaneous emphysema?Accessory muscle use?/hypertrophy?
Assessment of Airway/Ventilatory Compromise
Focused Exam Chest
Barrel chest?Deformity, discoloration, asymmetry?Flail segment, paradoxical movement?Adventitious breath sounds?Third heart sound?Subcutaneous emphysema?Fremitus?Dullness, hyperresonance to percussion?
Assessment of Airway/Ventilatory Compromise
Focused Exam Extremities
Edema?Nail bed color?Clubbing?
Assessment of Airway/Ventilatory Compromise
Mechanical Ventilation Increased resistance Changing compliance
Assessment of Airway/Ventilatory Compromise
Pulsus Paradoxus Systolic BP drops > 10 mm Hg
w/inspiration May detect change in pulse quality COPD, asthma, pericardial tamponade
Assessment of Airway/Ventilatory Compromise
History Onset gradual or sudden? What makes it worse, better? How long? Cough? Productive? Of what? Pain? What kind? Fever?
Assessment of Airway/Ventilatory Compromise
Past History Hypertension, AMI, diabetes Chronic cough, smoking, recurrent “colds” Allergies, acute/seasonal SOB Lower extremity trauma, recent surgery,
immobilization
Interventions Past admission? Ever admitted to ICU? Medications? Frequency of prn medication use? Ever intubated before?
BLS Airway/Ventilation Methods
Supplemental Oxygen Increased FiO2 increases available
oxygen Objective = Maximize hemoglobin
saturation
Oxygen Equipment
Oxygen source Compressed gas
Tank size• D 400L• E 660L• M 3450 L
Liquid oxygen
Oxygen Equipment
Regulators High Pressure
Cylinder to cylinder Low Pressure
Cylinder to patient
Humidifier
Delivery Devices
Nasal cannulaSimple face maskPartial rebreather maskNon-rebreather maskVenturi maskSmall volume nebulizer
Nasal Cannula
Optimal delivery 40% at 6 LPMIndication
Low FiO2
Long term therapyContraindications
Apnea Mouth breathing Need for High FiO2
Venturi Mask
Specific O2 Concentrations 24% 28% 35% 40%
Simple Face Mask
Range 40-60% at 10 LPMVolumes greater that 10 LPM does
not increase O2 deliveryIndications
Moderate FiO2
Contraindications Apnea Need for High FiO2
Non-Rebreather Mask
Range 80-95% at 15 LPMIndications
Delivery of high FiO2Contraindications
Apnea Poor respiratory effort
Partial Rebreather
Range 40 – 60%Indications
Moderate FiO2
Contraindications Apnea Need for High FiO2
BLS Airway/Ventilation Methods
Airway Maneuvers Head-tilt/Chin-lift Jaw thrust Sellick’s maneuver
Other Types Tracheostomy with tube Tracheostomy with stoma
Airway Devices Oropharyngeal airway Nasopharyngeal airway
BLS Airway/Ventilation Methods
Mouth-to-MouthMouth-to-NoseMouth-to-MaskOne-person BVMTwo-person BVMThree-person BVMFlow-restricted, gas powered ventilatorTransport ventilator
BLS Airway/Ventilation Methods
Mouth to MouthMouth to NoseMouth to Mask
BLS Airway/Ventilation Methods
One-Person BVM Difficult to master Mask seal often inadequate May result in inadequate tidal volume Gastric distention risk Ventilate only until see chest rise
BLS Airway/Ventilation Methods
Two-person BVM Most efficient method Useful in C-spine injury improved mask seal, tidal volume
Three-person BVM Less utilized Used when difficulty with mask seal Crowded
BLS Airway/Ventilation Methods
Flow-restricted, gas-powered ventilator Cardiac sphincter opens at 30 cm H2O High volume/high concentration Not recommended for children, poor
pulmonary compliance, or poor tidal volume
Oxygen delivered on inspiratory effort May cause barotrauma
BLS Airway/Ventilation Methods
Automatic transport ventilators Not like “real” ventilator Usually only controls volume, rate Useful during prolonged ventilation times Not useful in obstructed airway, increased
airway resistance Frees personnel Cannot respond to changes in airway
resistance, lung compliance
BLS Airway/Ventilation Methods
Pediatric considerations Mask seal force may obstruct airway Best if used with jaw thrust BVM sizes: neonate, infant=450 ml + Children > 8 y.o. require adult BVM Just enough volume to see chest rise Squeeze - Release - Release
BLS Airway/Ventilation Methods
Stoma patients Expose stoma Pocket mask BVM
Seal around stoma siteSeal mouth, nose if air leak is evident
BLS Airway/Ventilation Methods
Airway obstruction techniques Positioning Finger sweep with caution Suctioning Oral airway/nasal airway (tongue) Heimlich maneuver Chest thrusts Chest thrust/back blows for infants Direct laryngoscopy
BLS Airway/Ventilation Methods
Suctioning Manual or powered devices Suction catheters
RigidSoft
BLS Airway/Ventilation Methods
Gastric Distention Common when ventilating without
intubation Complications
Pressure on diaphragmResistance to BVM ventilationVomiting, aspiration
Increase BVM ventilation time
Recommended