Dr majidinejad
We describe basic airway skills, including
opening the airway, O2 therapy, BMV, and
extraglottic airway (EGA) devices
 Upper
airway obstruction most commonly
occurs when patients are unconscious or
sedated
 In these situations, tongue moves posteriorly into the upper airway when the
patient is in supine position

but research in patients with obstructive
sleep apnea using CPAP supports the concept
that the airway collapses like a fexible tube
 It
is widely accepted that the jaw-thrust-only
(without head tilt) maneuver should be
performed in patients with suspected
cervical spine injury, but there is no
evidence that it is safer than the headtilt/chin-lift maneuver
 Importantly,
the addition of CPAP may
relieve airway obstruction when simple
manual positioning maneuvers fail.
 most
common description of this maneuver is
head tilt, jaw thrust, and mouth
opening.
 Other authors describe the triple maneuver
differently—as a combination of upper
cervical extension (head tilt), lower cervical
felxion, and jaw protrusion (jaw lift)
best way to position a patient’s head and
neck for opening the upper airway is
“sniffng position
 In normal-sized supine adults, this is
accomplished by elevating the head about 10
cm while tilting the head back

 Morbidly
obese patients require much more
head elevation to achieve the proper sniffng
position
 In
young children, this position is often
achieved without lifting the head because
the occiput of a child is relatively large
Intervention is required when the patient is
not moving air or has altered mental status.
 Some patients with upper airway obstruction
can be ventilated and oxygenated with
aggressive high-pressure BMV, so always try
this if standard BMV fails

 Heimlich
maneuver is most effective when a
solid food bolus is obstructing the larynx
 If a choking patient loses consciousness,
use chest compressions in an attempt to
expel the obstructing agent
 After 30 seconds of chest compressions,
remove the obstructing object if you see it,
attempt 2 breaths
It is important to realize that more than one
technique is often required to clear
obstruction
 Finger sweep of the patient’s mouth only if
a solid object is seen
 It is recommended that suction be
performed on newborns rather than giving
them back blows or abdominal thrusts

 in
cases in which obstructive foreign
bodies cannot be removed under direct
visualization and aggressive ppv has
failed, practitioners can try to push a
subglottic foreign body beyond the carina.
A
large-bore dental-type suction tip is the
most effective in clearing vomitus from the
upper airway because it is less likely to
become obstructed by particulate matter
A
large-bore dental-type tip device, such as
the HI-D Big Stick suction tip, should be
readily available at the bedside during all
emergency airway management

Interposition of a suction trap close to the
suction device prevents clogging of the
tubing with particulate debris
A trap that fits directly onto a tracheal tube
has been described, and use of this device
allows effective suctioning during intubation
 Do
not exceed 15 seconds for suctioning
intervals and administer supplemental O2
before and after suctioning
 When feasible, perform suctioning under
direct vision or with the aid of the
laryngoscope
 Patients
who are unresponsive or apneic are
usually easier to ventilate with a bag-mask
device when an oropharyngeal airway is in
place.
 In the ED, patients who tolerate an
oropharyngeal airway should probably be
intubated
 Some
clinicians use a nasopharyngeal airway
to dilate the nasal passages for 20 to 30
minutes before nasotracheal intubation
 The
nasal airway is better tolerated by
semiconscious patients and is less likely to
induce vomiting in those with an intact gag
refex
 Resuscitate
all patients in cardiac or
respiratory arrest with 100% O2.
 indication for supplemental O2 defned as a
PaO2 lower than 60 mm Hg or (SaO2) less
than 90%.
 memory loss at (PaO2) of 45 mm Hg, and
loss of consciousness occurs at a PaO2 of
30 mm Hg.
 Chronically hypoxemic patients can adapt
and function with a PaO2 of 50 mm Hg or
lower
 tissue
hypoxia
 Shock state
 Respiratory distress without documented
arterial hypoxemia
 acute MI
 Administer 100% O2 to patients with
carbon monoxide poisoning

Use caution when administering
supplemental O2 to hypoxic patients with
(PaCO2) higher than 40 mm Hg, but do not
withhold it
 fear
of oxygen toxicity should not prevent
use of O2 when there is an indication but
should encourage to use minimum
concentration of O2 necessary to an spO2
≥94%( therapeutic goals)
 High-flow
delivery systems provide an FIO2
that is relatively constant despite changes
in the patient’s respiratory pattern
 The
Venturi mask is the high-flow delivery
device that is most widely available
 minimizing
changes in FIO2 as the
patient’s respiratory pattern changes

The mask is continuously flushed by the
high flow of gas, which prevents the
accumulation of exhaled gas in the mask
inspiratory flow rate for a resting adult
is about 30 L/min, a rate matched by the
total gas flow provided by the Venturi mask
at all settings
 A patient in respiratory distress may have
an inspiratory flow rate of 50 to 100
L/min.
 If inspiratory flow rate exceeds the total
gas flow delivered by the mask, additional
air will be entrained around the mask, and
FIO2 will decrease

 Low-flow
delivery devices provide gas flow
that is less than the patient’s inspiratory flow
rate. The difference between the patient’s
inspiratory flow and the flow delivered by
the device is met by a variable amount of
room air being drawn into the system

in simple mask complex interplay between
mask volume, tidal volume, respiratory
rate, and O2 flow determines the FIO2
delivered to the patient
A
partial rebreathing mask incorporates a
bag-type reservoir to increase the amount of
O2 available during inspiration thereby
requiring less outside air to be entrained

Nonrebreathing masks are similar to partial
rebreathing masks but have a series of oneway valves
 One
valve lies between the mask and the
reservoir and prevents exhaled gas from
entering the reservoir

Two valves in the side of the mask permit
exhalation while preventing the entry of
outside air
Many clinicians have the misconception
that a non-rebreathing mask can provide an
FIO2 near 100%.
 In practice, a non-rebreathing mask usually
delivers an FIO2 of about 70%


Highflow systems should generally be used
for patients who need precise control of
FIO2, such as COPD patients with chronic
respiratory acidosis
 An
oxygen flow rate of 1 to 3 L/min by nasal
cannula will result in an FIO2 of 23% to 35%.
Patients with signifcant hypoxemia, endorgan dysfunction, or respiratory distress
require a higher FIO2 delivery system
 An
initial FIO2 of 24% to 28% delivered by
Venturi mask is indicated for patients with
hypoxemia and chronic respiratory acidosis

Equilibration of SaO2 after changes in
supplemental O2 occurs within 5 min
 FIO2
should be titrated to achieve
therapeutic goals while minimizing the risk
for complications
 An SaO2 of 90% to 95% (PaO2 ≈ 60 to 80
mm Hg) is an appropriate target
 In
patients with COPD-associated
hypercapnia, an SaO2 of 90% (PaO2 ≈ 60
mm Hg) should be the goal of O2 therapy
 Preoxygenation
is usually accomplished by
providing the maximal FIO2 with a
nonrebreather mask for 3 to 5 min before
intubation
 Alternatively,
eight vital capacity breaths
from a maximal FIO2 system, such as a
nonrebreather mask or a bag-valve-mask
device, is acceptable when there is no
time for standard preoxygenation
 The
purpose of preoxygenation is not
just to maximize oxygen saturation but to
wash out nitrogen from the patient’s lungs
and replace it with oxygen
 Morbidly
obese patients are best
preoxygenated in a 25-degree head-up
position
 Sometimes
patients who need
preoxygenation the most are uncooperative
 These patients may beneft from delayedsequence intubation—careful to allow
oxygenation with a face mask or NPPV for 2
to 3 min before administering a paralytic
agent.
 Ketamine (1 to 1.5 mg/kg by slow intravenous push) has been suggested for this
technique
 Another
method to delay desaturation during
RSI is nasopharyngeal oxygen insuffation
during apnea
Using a standard nasal cannula with a
nasopharyngeal airway is simpler and
would probably provide the same beneft
 Also, it is important to keep the upper
airway open by using a jaw thrust or artifcial
airway for this technique to be most
benefcial

 high-flow
nasal oxygen is a relatively new
concept that may have some utility for
optimizing oxygenation in critically ill
children and adults
 Many
authors note that BMV is relatively
contraindicated in patients with a full
stomach, those in cardiac arrest, and those
undergoing RSI

goal is to achieve adequate gas exchange
while keeping peak airway pressure low

the best method of BMV is to provide a tidal
volume of about 500 mL delivered over a
period of 1 to 1.5 seconds
Generally, wellfitting intact dentures should
be left in place to help ensure a better seal
with the mask
 it is important to remember to use
oropharyngeal or nasopharyngeal airways (or
both) whenever face mask ventilation is
diffcult

 All
bag-mask devices should be attached to a
supplemental O2 source (with a flow rate
of 15 L/min) to avoid hypoxia

A 2500-mL bag reservoir and a demand
valve are preferred for O2 supplementation
during BMV

A recent study showed that most patients
with diffcult BMV became easier to
ventilate after paralytic agents were
administered and none were more diffcult to
ventilate after paralytics

Applying Sellick’s maneuver during BMV
may further decrease the risk for gastric
infation and is still recommended by most
airway experts.

It should be noted that the routine use of
cricoid pressure during BMV of patients in
cardiac arrest is not recommended in the
2010 American Heart Association Guideline
 It
is recommended that cricoid pressure be
released immediately if there is any diffculty
ventilating with a face mask in an emergency
setting

EGAs can be divided into two groups, LMAs
and retroglottic devices
 intubating
LMA (ILMA) or a nonintubating
LMA can be inserted in less than 30 seconds
and provide effective ventilation in more
than 98% of patients
failure to ventilate and oxygenate with the
LMA occurs in about 6% of cases
 Another 6% of patients with diffcult
airways suffer episodes of hypoxia during
attempts to intubate through the LMA.
 There is evidence that ILMA performs
better in cannot-intubate/cannot-ventilate
situation.
 Failure to ventilate with the ILMA occurs
in only about 2% of cases, and hypoxia after
ILMA placement is very rare


almost all patients can be adequately
ventilated with the ILMA and 94% to 99% can
be intubated through the device
 When
brisk bleeding above the glottis makes
ventilation and intubation difficult, ILMA can
prevent aspiration of blood and facilitate
blind or fiberoptic intubation
 In
patients requiring urgent cricothyrotomy
or percutaneous needle insertion into the
trachea the ILMA can be used to counteract
anterior neck pressure
 In
this capacity, ILMA provides temporary
ventilation and stabilizes the cervical
spine during the surgical airway procedure

ILMA is relatively contraindicated in awake
patients, especially those with a full
stomach

some evidence shows that ILMA causes
posterior pressure on midportion of
cervical spine
 device
is generally considered safe in
patients with an unstable cervical spine
injury

Incorrect ILMA size is more likely to be a
problem if the device is too small

If another ILMA size is not available,
external anterior neck manipulation or
downward pressure may bring the glottis
and ILMA cuff into proper alignment

best patient position for insertion of LMA is
sniffng position, with neck flexed and
head extended
 Sometimes
adjusting the patient’s head and
neck position is easier than trying to change
the position of the LMA if cuff seal
 sniffng
position or into the chin-to-chest
position

jaw -thrust or a chin-lift maneuver
 anterior
neck pressure to help manipulate
glottis into improved contact with LMA mask
 withdraw,


advance, or rotate LMA cuff
completely remove
If unsuccessful, change the size of the
LMA. A larger LMA

aspiration of gastric contents and
hypoxia
 there
is evidence that it provides some
protection from passive regurgitation and
produces less gastric infation than BMV does

King LT has only one airway lumen and a
simplifed cuff system, so both cuffs can be
infated from a single port
 tip
of the King LT is designed to be placed in
esophagus only
 Size
3 is yellow and designed for patients 4
to 5 feet in height, size 4 is red and
designed for patients 5 to 6 feet in height,
and size 5 is purple and designed for
patients taller than 6 feet
 best
patient position for insertion is sniffng
position, but it can be placed with the
head in the neutral position if necessary
Introduce tip of device into corner of
mouth while rotating the tube 45 to 90
degrees so that the blue orientation line on
the tube is touching corner of the mouth
 As the tip passes under the base of tongue,
rotate the tube back to the midline so that
blue orientation line faces the ceiling
 Without exerting force, advance King LT
until connector is aligned with teeth

 The
Combitube not recommended in
patients shorter than 4 feet
 It is contraindicated in patients with
suspected caustic poisoning or proximal
esophageal disorders
 The

Combitube is available in two sizes
smaller 37-Fr device for patients 4 feet to 5
feet 6 inches tall and the larger 41-Fr device
for patient taller than 5 feet 6 inches

If resistance is met in the hypopharynx,
remove tube and bend it between the
balloons for several seconds to facilitate
insertion.

After insertion, fill the pharyngeal balloon
with 100 mL of air and the distal cuff with
10 to 15 mL of air

Alternatively, use a Wee-type aspirator
device on the shorter (clear) lumen to
confirm that the tip is in the esophagus
before ventilation through the longer
(blue) lumen
 If
there is confusion about location of
Combitube tip, use capnography to ensure
that correct airway tube is being ventilated
 The
Combitube must also be maintained in
the true midline position during insertion to
avoid blind pockets in supraglottic area
 Our
goal should be to avoid RSI in
patients who cannot be ventilated with a
bag-mask device and cannot be intubated
by direct or video laryngoscopy.

if RSI is our usual method of intubation,
we must be prepared to perform a surgical
airway when laryngoscopy, BMV, and backup
devices fail