Airway (Crash Course)

cellular respiration
cellular processes that convert energy from nutrients into ATP, and then release waste products

Exhalation
passive part of breathing

external respiration
o2 exchange between the lungs and circulatory system

hypoxia
oxygen deficiency

Inhalation
Active part of breathing

internal respiration
o2 exchange between blood and cells of the body

minute volume
volume of gas inhaled or exhaled per minute (respiratory rate x tidal volume)

oxygenation
Delivery of oxygen to the blood

ventilation
The physical act of moving air into and out of the lungs

Upper airway structures
nose and mouth, nasopharynx, oropharynx, epiglottis, larynx

lower airway structures
larynx, trachea, L and R mainstem bronchi, bronchioles, alveoli

early s/s of hypoxia
restlessness, anxious, irritable, tachycardia and tachypnea

late s/s of hypoxia
decreased LOC, severe dyspnea, cyanosis, bradycardia

CO2 drive
primary system for monitoring breathing status
monitors CO2 levels in blood and cerebrospinal fluid
chemoreceptors in brainstem detect increased CO2 and rapidly trigger increased respiratory rate

Hypoxic drive
backup system to CO2 drive
monitors o2 levels in pts
may be present in end-stage COPD pts
prolonged exposure to high concentration o2 in hypoxic drive pts can cause respiratory depression

respiratory acidosis
low pH, high CO2

respiratory alkalosis
high pH, low CO2

metabolic acidosis
low pH, low HCO3

metabolic alkalosis
high pH, high HCO3

ventilation-perfusion mismatch
occurs when lungs receive o2, but not adequate blood flow or when the lungs receive blood flow, but inadequate o2.

manual airway techniques
headtilt chin lift(preferred)
jaw thrust(spinal injury)

rigid suction catheter
also known as a 'tonsil tip' or Yankauer, best suited for suctioning the oral airway

french suction catheter
flexible catheter also called a whistle tip, used to suction nose, stoma, or inside advanced airway

basic adjuncts
OPA, NPA

extraglottic, retroglottic and supraglottic airway devices
LMA, i-gel supraglottic LMA, pharyngeal tracheal lumen airway, esophageal tracheal combitube, king LT, supraglottic airway laryngopharyngeal tube

endotracheal intubation advantages
isolates the trachea
eliminates gastric distention from ventilation
no mask seal needed
improved suctioning ability
route for medication admin.( narcan, epi, atropine, lidocaine)

endotracheal intubation disadvantages
extensive training required
direct visualization of vocal cords required
takes longer than other advanced airwas
has many serious complications
not been shown to increase survival rates

verification of proper ETT placement
direct visualization of cords
auscultation of epigastrium and bilateral lung fields
continuous waveform capnography
pulse ox
esophageal detector device
ETT introducer

Surgical Cricothyrotomy
only indicated in acute, life threatening situations when use of less invasive airway techniques are ineffective

RSI indications
respiratory failure, inability to protect airway, combative pt, persistent hypoxia

RSI contraindications
respiratory and cardiac arrest, anticipated difficult airway, short transport time, ability to manage airway w/less invasive measures, neuromuscular disease, e.g., ALS, muscular dystrophy

predictors of difficult advanced airway insertion
mouth does not fully open
hypersecretions
obesity
pulmonary edema
airway burns
facial trauma

Mallampati score class 1
entire tonsil clear

Mallampati score class 2
upper half of tonsil visible

Mallampati score class 3
soft and hard palate visible

Mallampati score class 4
only hard palate visible

mnemonic for difficult airway
look externally
evaluate 3-3-2 rule
mallampati score
obstruction
neck mobility
saturations

indications for supplemental oxygen
dyspnea
hypoxia
pulse ox below 94%
altered or decreased LOC
respiratory or cardiac arrest
hypoperfusion(shock)

supplemental oxygen devices
nasal cannula
NRB
small volume nebulizer

o2 cylinder D
about 350-liter capacity

o2 cylinder E
about 625-liter capacity

o2 cylinger M
about 3,000-liter capacity

full cylinder pressure
2,000 PSI

safe residual pressure
200 psi

pin-indexing system
safety feature that prevents an o2 regulator from being connected to a tank w/any other compressed gas

calculating duration of an o2 tank
(cylinder PSI-safe residual pressure) x tank constant/ remaining flow rate(lpm) =min.

D cylinder tank constant

0.16

E cylinder tank constant

0.28

M cylinder tank constant

1.56

initiate PPV for pts w/any signs of inadequate breathing like:
excessive bradypneic
shallow breathing
altered or decreased LOC
dyspnea
retractions
accessory muscle use
cyanosis
paradoxical motion
sucking chest wound

complications of PPV
increased intrathoracic pressure and reduced cardiac output
gastric distention and increased risk of vomiting

agonal respirations
slow, shallow, infrequent reaths; indicates brain anoxia

Biot's respirations
irregular pattern of rate and depth and periodic apnea; indicated increased ICP

Central neurologic hyperventilation
deep, rapid respirations; indicates increased ICP

Cheyne-Stokes respiration
progessively deeper and faster breaths, changing to slower and shallow breaths; indicates brain injury

Kussmaul respirations
deep, gasping breaths; indicates possible DKA

Rales(crackles)
fine, bubbling sound on inspiration; indicates fluid in lower airways

Rhonchi
course sounds on inspiration; indicates inflammation or mucus in lower airways

Wheezes
high-pitched sound on inspiration or expiration; indicates bronchoconstriction

Snoring
indicates partial airway obstruction from the tongue

Stridor
high pitched sound indicating significant upper airway obstruction

Gurgling
indicates fluid in the upper airway

normal CO2 and ETCO2 values
35-45mmHg

high ETCO2
possible hypoventilation

low ETCO2
possible hyperventilation

ETCO2 drops to 0
possible for esophageal intubation or displaced tube

sharp drop in ETCO2
possible pulmonary embolism, cardiac arrest, hypotension, hyperventilation

indications of CPAP
alert & spontaneously breathing pts
12yrs of age
significant respiratory distress (sleep apnea, COPD, pulmonary edema, CHF, pneumonia)

Contraindiations of CPAP
apnea
pts unable ot follow verbal commands
suspected pneumothorax
chest trauma
tracheostomy
vomiting
GI bleeding
hypotension

care for a trach tube/stoma
bvm
infant bvm
require frequent suctioning

BLS care for foreign body obstruction
conscious pts=abd thrusts
unconscious pts=chest compressions
conscious pts= back blows and chest thrusts

ALS care for foreign body obstruction
attempt to remove w/laryngoscope & Magill forceps
attempt ETT insertion to try passing tube through obstruction or forcing it into right mainstem

care for respiratory burns
consider rapid intubation due to swelling