Management of a Difficult Airway Flashcards
If unable to see vocal cords or pass ETT during first DL:
- Consider External Laryngeal Manipulation, BURP (Backwards Upwards
Rightwards Pressure). - Consider placing Bougie introducer.
- Limit total number of DL attempts to 2.
- Recommend Video-Assisted Laryngoscopy.
- Before repeating DL, consider mask ventilation with oral/nasal airways.
- Consider optimizing patient position and/or blade selection.
If you cannot intubate then:
- attempt face mask ventilation
2. call for difficult airway cart
If you CAN ventilate:
If ventilation remains adequate, CONSIDER: 1. Awakening patient. 2. Complete case with LMA or face mask. 3. Video-assisted Laryngoscopy. 4. Asleep fiberoptic bronchoscopy. 5. LMA as conduit for intubation or intubating LMA. 6. Retrograde wire intubation.
If you can NOT ventilate:
- CALL FOR HELP
- Place oral, nasal airway and
switch to two-handed mask ventilation. - Place LMA if feasible.
If you STILL can NOT ventilate & becoming an EMERGENCY:
- Call for Surgical Help.
- Perform Cricothyrotomy.
- Confirm successful placement with ETCO2 and bilateral breath sounds
Options for known difficult airways:
(1) awake intubation
(2) video-assisted laryngoscopy,
(3) intubating stylets or tube-changers,
(4) LMA, laryngeal tube
(5 ) fiberoptic-guided intubation
-consider regional anesthesia
When to Cric?
If the patient cannot be awakened, emergency airway access must be attempted in a life-threatening situation in which the patient cannot be ventilated or intubated.
Exam component and nonreassuring findings:
- Length of upper incisors = Relatively long
- Relationship of maxillary and mandibular incisors
during normal jaw closure
= Prominent “overbite” (maxillary incisors anterior to mandibular incisors) - Relationship of maxillary and mandibular incisors
during voluntary protrusion of mandible = Patient cannot bring mandibular incisors anterior to (in front of) maxillary incisors - Interincisor distance = Less than 3 cm
- Visibility of uvula = Not visible when tongue is protruded with patient in sitting position (e.g., Mallampati class >2)
- Shape of palate = Highly arched or very narrow
- Compliance of mandibular space = Stiff, indurated, occupied by mass, or nonresilient
- Thyromental distance = Less than three ordinary finger breadths
- Length of neck = Short
- Thickness of neck = Thick
- Range of motion of head and neck = Patient cannot touch tip of chin to chest or cannot extend neck
Patients that will not tolerate an apneic period?
patients who are obese, are pregnant, or have pulmonary disease, peds
Alterations to induction to consider for difficult airways
- IV induction or Inhalation induction
- Choice of NMBA (duration, reversal)
You have induced general anesthesia, given a paralytic and attempted direct laryngoscopy and found a grade 4 view. You attempt to mask ventilate and do not get chest rise or ETCO2. What are your next immediate actions?
Attempt to place a supraglottic airway
Call for help
Other significant airway-related complications include?
-aspiration of gastric contents, laryngospasm, bronchospasm
Reasons why anesthetist is unable to provide adequate ventilation?
-inadequate mask or LMA seal, excessive gas leak, excessive resistance to the inward/outward movement of gas.
S/S of inadequate ventilation
-absent chest movement or breath sounds, cyanosis, decreasing Spo2, absent or inadequate ETco2, hemodynamic changes associated with hypoxia or hypercarbia (HTN, hypotension, tachycardia, arrhythmia)
Difficult laryngoscopy:
-it is not possible to visualize any portion of the vocal cords after multiple attempts at DL
Difficult intubation:
-tracheal intubation requires multiple attempts in the presence or absence of tracheal pathology
Failed intubation:
placement of the ETT fails after multiple attempts
strategies for difficult airways
- awake intubation
- video-assisted
- fiber-optic intubation
- use of stylets or tube-changers
- SGAs for ventilation
Difficult mask ventilation
Inability of an unassisted anesthesia clinician to maintain alveolar
oxygen delivery or reverse signs of inadequate ventilation
inappropriate airway management often cited in malpractice
- inadequate evaluation
- failure to plan for difficult intubation
- failure to use a supraglottic airway for rescue
- delay in calling for help
- perseveration on failed techniques
good questions to direct airway management:
- Is airway control required?
- Could laryngoscopy be difficult?
- Could supraglottic ventilation be used?
- Is there risk of aspiration?
- Will the patient tolerate a period of apnea?
Difficult airway suspected on a patient whose stomach is not empty
-Patients predicted to be difficult to intubate who have not fasted or who are
otherwise at high risk for regurgitation and aspiration of gastric contents should be intubated awake and in control of their airway reflexes whenever possible
-consider spraying local anesthetic solution through the
flexible bronchoscope as it is advanced during the process of laryngoscopy and intubation
-The key to awake intubation in the patient with a full stomach is a smooth course, with avoidance of
gagging, coughing, and vomiting
-RSI (requires ability to intubate rapidly) may be inappropriate for patients who may be difficult to intubate
Factors that complicate an awake intubation
- cognitive disability
- altered mental status
- extreme anxiety
- uncooperative
Why is an awake intubation ideal in a known difficult airway?
-we preserve spontaneous ventilation, patient cooperation and airway reflexes
Choice of induction technique when difficult airway management is predicted:
-IV induction is used when there is a high
likelihood of successful ventilation by mask, SGA, or endotracheal intubation and the patient is not at significant
risk of gastric contents aspiration or rapid desaturation
-use short-acting drugs
-careful consideration of the NMBA
-When maintenance of spontaneous ventilation is preferred, an inhalation induction may be used, though IV access should be established prior to inhalation induction.
Preferred airway device for a patient with a potentially difficult airway
ETT is considered by many to be the definitive method of
airway control, however, not every patient requires endotracheal intubation, including the patient with a potentially difficult airway.
Regardless of the technique chosen for airway management, *a backup plan MUST be in place, with the necessary expertise and equipment immediately
available
When to consider a SGA
Many patients who are predicted to be difficult to intubate and/or mask
ventilate can be successfully ventilated with a SGA.
SGAs can be considered for use as the primary airway
device when the risk of aspiration is relatively low and the need for higher airway pressures is not
anticipated
A SGA specifically designed to allow intubation through the device may be a good choice for the patient who may be difficult to intubate
When airway evaluation necessitates a surgical airway:
- if known, always have the surgical team consulted as part of the airway plan
- if unknown, call for surgical help ASAP
If a surgical airway fails or is impossible
-consider fem/fem cardiopulmonary bypass, ECMO
Equipment preparation for a difficult airway
-have both routine and emergency airway equipment available
-have an assortment of standard and alternative airway devices including facemasks, appropriate sizes and types of laryngoscopes (direct, indirect, flexible), oral and nasal airways, supraglottic airways (SGAs), bougies, and equipment for front-of-neck
access
-have the emergency airway cart nearby
-always call for help earlier rather than later
preparation for an awake intubation
- the administration of a drying agent (eg, glycopyrrolate 0.2
mg IV), nasal mucosal vasoconstrictors (if nasal intubation is a possibility), and anesthetic blocks (topical spray or invasive) of the upper airway.
Timing of administration of NBMA
-mask ventilation should be established prior to
the administration of NMBAs. In theory, this sequence allows the clinician to prove his or her ability to ventilate
the patient before removing the patient’s ability to ventilate on his or her own, while maintaining the option to
awaken the patient should attempts at airway control fail.
-but also consider that NMBAs may improve mask ventilation,
especially when difficulty is the result of laryngospasm, opioid-induced rigidity, or light anesthesia.
NMBA choice when difficult mask ventilation is predicted
when mask ventilation is predicted to be difficult, but laryngoscopy is predicted to be straightforward, a strategy that allows rapid intubation while minimizing the need for
mask ventilation should be employed. Options include:
Succinylcholine – a depolarizing NMBA. At a dose of 1 to 1.5 mg/kg IV,
blockade is complete in approximately one minute, and recovery occurs in only six to nine minutes
Rocuronium – a nondepolarizing NMBA. At a dose of 0.9 to 1.2 mg/kg IV,
blockade is complete in less than two minutes, with a variable, long duration of action (38 to 150 minutes)…. but Roc is reversible with sugammadex…..
Inhalation induction for a difficult airway
- used to better maintain spontaneous ventilation until airway control (with facemask, SGA, or ETT) has been confirmed
- may be preferred in patients predicted to have difficulty with intubation but NOT with mask ventilation.
- IV access should be obtained in adults prior to inhalation induction
- preoxygenate
- Sevo is agent of choice
- start low and gradually increase concentration
Various maneuvers may improve the ability to mask ventilate
- place an oral or nasal airway
- maneuvers to open upper airway (head tilt, chin lift, jaw thrust)
- two-person mask technique
awake intubation, instrument choice
- flexible scope intubation
- FSI through an endoscopy mask or an SGA permits ventilation during intubation.
following an unsuccessful intubation attempt you should?
-attempt/resume mask ventilation
limit attempts with any particular device
-Repeated instrumentation of the airway may lead to bleeding, edema, and further deterioration of the ability to
ventilate
if attempting a second time you should
-optimize conditions between attempts; for example, by improving head and neck position, changing
laryngoscope blade, using a different device, or by having a more experienced clinician manage the airway.
BURP stands for?
Thyroid cartilage pressure - backward, upwards, right pressure… attempting to improve laryngoscopic grade & bring cords into better view
Cricoid pressure
decreases LES tone to prevent aspiration
controversial
contraindicated in unstable C-spine or active vomiting
