3. Basic Airway Management and Decision Making
Dr majidinejad

4. We describe basic airway skills, including opening the airway, O2 therapy, BMV, and extraglottic airway (EGA) devices

5. Opening the Airway
Upper airway obstruction most commonly occurs when patients are unconscious or sedated
In these situations, tongue moves pos-
teriorly into the upper airway when the patient is in supine position

6. Manual Airway Maneuvers
but research in patients with obstructive sleep apnea using CPAP supports the concept that the airway collapses like a fexible tube

8. 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 head- tilt/chin-lift maneuver

9. Importantly, the addition of CPAP may relieve airway obstruction when simple manual positioning maneuvers fail.

10. The Triple Airway Maneuver
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)

11. Patient Positioning
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

12. Morbidly obese patients require much more head elevation to achieve the proper sniffng position

14. In young children, this position is often achieved without lifting the head because the occiput of a child is relatively large

15. Foreign Body Airway Obstruction
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

18. 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

19. 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

20. 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.

21. Suctioning
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

24. 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

25. 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

27. 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

28. Oropharyngeal and Nasopharyngeal Artifcial Airways
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

32. 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

33. OXYGEN THERAPY
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

34. Indications and Contraindications
tissue hypoxia
Shock state
Respiratory distress without documented arterial hypoxemia
acute MI
Administer 100% O2 to patients with carbon monoxide poisoning

35. Use caution when administering supplemental O2 to hypoxic patients with (PaCO2) higher than 40 mm Hg, but do not withhold it

36. 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)

37. Oxygen Delivery Devices
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

40. 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

41. 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 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

42. 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

44. in simple mask complex interplay between mask volume, tidal volume, respiratory rate, and O2 flow determines the FIO2 delivered to the patient

45. 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

46. Nonrebreathing masks are similar to partial rebreathing masks but have a series of one- way 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

47. 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%

49. Highflow systems should generally be used for patients who need precise control of FIO2, such as COPD patients with chronic respiratory acidosis

50. 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, end- organ dysfunction, or respiratory distress require a higher FIO2 delivery system

51. 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

52. 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

53. In patients with COPD-associated hypercapnia, an SaO2 of 90% (PaO2 ≈ 60 mm Hg) should be the goal of O2 therapy

54. Preoxygenation for Rapid-Sequence Intubation
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

56. 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

57. Sometimes patients who need preoxygenation the most are uncooperative
These patients may beneft from delayed- sequence 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 intra-
venous push) has been suggested for this technique

58. 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

59. Nasal High-Flow Oxygen
high-flow nasal oxygen is a relatively new concept that may have some utility for optimizing oxygenation in critically ill children and adults

61. BAG-MASK VENTILATION
Many authors note that BMV is relatively contraindicated in patients with a full stomach, those in cardiac arrest, and those undergoing RSI

62. 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

64. 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

65. All bag-mask devices should be attached to a supplemental O2 source (with a flow rate of 15 L/min) to avoid hypoxia
A mL bag reservoir and a demand valve are preferred for O2 supplementation during BMV

67. 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

68. 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 American Heart Association Guideline

69. It is recommended that cricoid pressure be released immediately if there is any diffculty ventilating with a face mask in an emergency setting

70. EXTRAGLOTTIC AIRWAY DEVICES
EGAs can be divided into two groups, LMAs and retroglottic devices

71. LMAs 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

73. 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

74. 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

75. 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

76. 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

81. 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

83. LMA Classic

85. 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

86. 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

87. withdraw, advance, or rotate LMA cuff
completely remove
If unsuccessful, change the size of the LMA. A larger LMA

88. Complications 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

90. Retroglottic Airway Devices

92. 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

93. Placement of the King LT
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

94. best patient position for insertion is sniffng position, but it can be placed with the head in the neutral position if necessary

95. 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

96. Combitube and EasyTube
The Combitube not recommended in patients shorter than 4 feet
It is contraindicated in patients with suspected caustic poisoning or proximal esophageal disorders

98. 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

99. 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

100. 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

101. The Combitube must also be maintained in the true midline position during insertion to avoid blind pockets in supraglottic area

102. 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.

103. if RSI is our usual method of intubation, we must be prepared to perform a surgical airway when laryngoscopy, BMV, and backup devices fail