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management of acute airway obstruction

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Management of Acute Airway Obstruction
Consideration for Bronchoscopy
and
Topicalization of Airway ASA Difficult
Airway Algorithm
Dr. Suman Shrestha
Dep of Anaesthesiology
1st year resident,PAHS
OBJECTIVES
• To know about causes and pathophysiology of acute airway
obstruction.
• To know about the approach for management of acute
airway obstruction.
• To know about bronchoscopy and its consideration.
• To know about ASA difficult airway Algorithm.
What is an Airway?
• The path air follows to get into and out of the lungs.
• The mouth and nose are the normal entry and exit ports.
• Entering air then passes through nose, the paranasal
sinuses, the back of the throat (pharynx),continues through
the voice box (larynx), down the trachea, and finally out
the branching tubes known as bronchi.
Respiratory Anatomy
What is Airway Obstruction?
• Any obstacle from Mouth to Lungs
• May be Partial or Complete
• Limitation of air entry into Lungs
• Causing Lack of O2 Inflow or CO2 Outflow
• Relieving obstruction is very important for LIFE!
Introduction
 Obstruction of the airway at its most extreme is an anaesthetic
emergency requiring immediate intervention.
 In advanced life support algorithms, it usually refers to loss ofairway
patency in the unconscious patient or blockage by a foreign body in
the event of choking.
 Airway obstruction may present acutely or chronically depending on
the site, degree of narrowing and cause.
 The anatomical level can broadly be categorised as supraglottic,
glottic (laryngeal) or subglottic.
Introduction
 The obstruction may be due to luminal pathology such as
inflammation, tumour or haematoma or it may result from
external compression and distortion.
 Central airway compromise due to anterior mediastinal
masses can pose difficulties by nature of the obstruction being
sited distal to surgical airway rescue.
 Management of the obstructed airway is particularly
challenging and accounted for 40% of all cases reported to the
4th UK National audit.
Mechanism of Airway Obstruction
LEVEL OF
OBSTRUCTION
PATHOLOGY
SIGN AND SYMPTOMS
Supraglottic
Oropharyngeal lesions base of
tongue, tumours, epiglottitis,
retropharyngeal abscess,
invasive high oesophageal
tumours
Dysphagia,drooling,stridor,Sno
ring,gurgling sounds,snorting
sound,muffled voice,visible
swelling
Glottic
Vocal cord paralysis, glottic
tumours, polyps
Stridor,paroxysmal nocturnal
dyspnea,voice
changes(hoarse cry,voices)
Subglottic
Tracheal stenosis, laryngomalacia,
subglottic tumours
Expiratory stridor
Distal tracheal
Lymphoma, thyroid mass,
mediastinal masses
Presentation of airway obstruction
Presentation of airway obstruction
 Shortness of breath,
 Increased work of breathing
 Respiratory fatigue and
distress
 Signs of use of accessory
muscles
 Tracheal tug
 Chest wall recession
 Hypoxia
 Difficulty in swallowing
 Agitated
 Weakening of cough
Why is it Important to Maintain
Airway?
• Sensitive organs like brain and heart can die within a
few minutes without O2.
• Patient becomes unconscious (hypoxia and hypercarbia)
and further risk of Aspiration.
• Trauma patient management of Airway comes FIRST.
• Crucial few minutes
Decision making in airway
obstruction
 How time critical is airway management?
 Will holding measures be useful?
For any lesion
 Where is the lesion?
 Is it mobile/fixed?
 Is it Annular/large/pedunculated/ball valve type?
 How does it influence airway intervention?
Predictors for difficult face
mask Ventilation
 Obesity
 Age 55 and above
 H/O snoring
 Lack of teeth
 Presence of Beard
 Mallampatti class III or IV
 Abnormal mandibular protrusion test
 Decreased inter dental distance
 Decreased thyromental distance
 Decreased neck movement
 Tumor or mass over neck
HOLDING MEASURES
 High flow nasal oxygen: Oxygen delivery via high-flow nasal
cannulae (HFNC) is revolutionising airway management.
 Steroid therapy: If there is inflammation or oedema associated with
the obstruction, steroids may be helpful, particularly in more elective
procedures where there is sufficient time for the drug to act.
 Nebulized epinephrine: Epinephrine is a vasoconstrictor and is
frequently utilized. It appears to be effective in reducing stridor in a
variety of case reports with varying obstructive aetiology.
 Heliox: (79% Helium plus 21% oxygen )Helium is a less dense
gas than oxygen, and this improves airflow, reducing the increased
work of breathing secondary to the obstruction by encouraging
laminar flow within the narrowed upper airway.
 Continuous positive airway pressure
ATLS (Advanced Trauma Life
Support)
 Performed in an injured / trauma patient
 Starts as BTLS on site of injury
 Consists of the following components:
 Airway
 Breathing
 Circulation
 We will only discuss the AIRWAY part of the trauma
protocol.
AIRWAY RESCUE METHODS
MANUAL MANOEUVRES:
 Mostly done at site, also in ambulance
Head tilt
finger
chin lift
jaw thrust
Clearing mouth with hooked
INSTRUMENTATION:
 If above unsuccessful, mostly ambulance/hospital facility
 Various artificial airways like
Ambu Bag, Oropharyngeal and Nasopharyngeal Airway,
Endotracheal Tube, Laryngeal Mask Airway
SURGICAL AIRWAY:
 If 2nd Option unsuccessful, almost always in hospital
 Surgical Creation/Bypass of Airway
 Includes Cricothyroidotomy and Tracheostomy.
MANUAL MANOEUVRES
See for Any Response / Call Name
Call for Help / Ambulance
MANUAL MANOEUVRES (cont….)
Head Tilt and Chin Lift (Opens the Oral Airway if Tongue Obstruction)
MANUAL MANOEUVRES (cont….)
Hear for Breathing, see chest movements If NO then start Mouth to Mouth
Breaths, but Nose must be pinched to Avoid Leakage of Air
MANUAL MANOEUVRES (cont….)
LATERAL LYING POSITION FOR A BREATHING UNCONSCIOUS PATIENT
Artificial Airways
AMBU Bag and Procedure
(Remember to do Head Tilt and
Chin Lift to Open the Airway
otherwise Bagging will be
Ineffective)
Oropharyngeal Airway (Guedel Airway)
Artificial Airways
(cont…)
Artificial Airways (cont…)
Nasopharyngeal Airway
Artificial Airways (cont…)
Laryngeal
Mask Airway
Artificial Airways (cont…)
Laryngoscope with Various Sizes of Blades (Left Picture) Used to Intubate 
Endotracheal Tube with Cuff (Right Picture)
Artificial Airways (cont…)
Laryngoscopic View of
Epiglottis and Glottis
(Laryngeal Opening) and
Endotracheal Tube In Place
Investigations for the
obstructed airway
 Nasendoscopy :A nasendoscopy is non invasive,quick to perform
,less airway irritation and providing a great deal of information about
the appearance of the airway without laryngospasm and loss of airway.
 Computed tomography : Computed tomography (CT) scans provide
a rapid and accurate assessment of the structures of the airway. It is
readily available, quick and usually well tolerated.
 Magnetic resonance imaging : Magnetic resonance imaging is
extremely good for delineating soft tissue structures and the physical
structure of the airway.
Basic management choices
Airway devices and techniques used to secure the airway.These are:
 Awake or asleep intubation.
 Spontaneous Ventillation or ablation of Spontaneous Ventillation
(e.g. applying positive pressure ventilation to paralysed patients).
 Non-invasive or invasive airway devices.
 Direct or indirect laryngoscopy to facilitate tracheal intubation.
Awake or asleep intubation
 Most patients with a normal appearance can be intubated after
induction of anaesthesia (asleep intubation).
 Anaesthesia causes airway obstruction and decrease in respiratory
reserve .The ‘margin of safety’ is narrowed, full pre-oxygenation
with the ‘three-minute tidal volume’ or ‘eight deep breath’ technique
and transnasal oxygen insufflation is beneficial, as it prolongs safe
apnoea time.
Awake or asleep intubation cntd.
 If face mask ventilation or intubation is predicted to be difficult, and
attempts are at high risk of morbidity, the airway should be secured
before induction of anaesthesia (awake intubation).
 This maximises the ‘margin of safety’, as airway muscle tone and
reflexes are maintained, and respiratory function is unaffected by
anaesthetic agents.
 It also avoids the risk of a post-induction ‘cannot intubate, cannot
ventilate’ (CICV) scenario, which has an incidence of 0.01%–
0.17%.
Preserved or ablated
spontaneous ventilation
 SV is preserved in the awake state or during anaesthesia after careful
titration of intravenous or volatile agents
 Under acceptable intubating conditions, induction takes approximately
six minutes using 7% sevoflurane in normal patients(56) but much
longer in patients with AAO, as the obstruction prevents delivery of the
volatile agent.
 induction and intubation with 8% sevoflurane without the use of muscle
relaxants is associated with a higher failed intubation rate(57) and up
to 10%–25% of upper airway complications, such as breath-holding
and coughing.
 In patients with AAO, laryngospasm is more common.Several cases of
failed gas induction leading to serious morbidity, including airway
obstruction, laryngospasm, failed intubation necessitating surgical
airway procedure, and cardiac arrest are reported.
Preserved or ablated
spontaneous ventilation
 A new strategy is to use a rapid-sequence dose of the intermediateacting rocuronium (1.2 mg/kg) and follow this with its reversal agent,
sugammadex (16 mg/kg), if bailout is required. This combination
gives a similar onset but faster offset time compared with
suxamethonium.
 the use of muscle relaxants in CICV cases as they may resolve
failure to ventilate caused by laryngospasm and aid mask ventilation
is recommended.
 In symptomatic patients with large mediastinal masses or
tracheobronchial lesions, maintaining SV and avoiding the use of
muscle relaxants is considered the safest option. The resulting
negative intrathoracic pressure helps to keep the intrathoracic
airways open.(
Noninvasive or invasive
airway devices
ACUTE EPIGLOTTITIS
• Epiglottitis describes inflammation of the epiglottis and
adjacent supraglottic structures.
• Sudden onset of sore throat and fever followed within a matter of
hours as toxic, swallowing difficulty, and labored breathing.
• Drooling of saliva and hyperextended neck, assume the tripod
position, sitting upright and leaning forward with the chin up
and mouth open while bracing on the arms.
ACUTE EPIGLOTTITIS
Radiographic features of epiglottitis include:
• An enlarged epiglottis protruding from the anterior wall of
the hypopharynx (the "thumb sign“)
•
•
•
•
Loss of the vallecular air space
Thickened aryepiglottic folds
Distended hypopharynx (nonspecific).
Straightening or reversal of the normal cervical lordosis
ACUTE EPIGLOTTITIS CONTD..
 Patient able to maintain airway
• supplemental humidified oxygen
• In young children, avoid increasing anxiety by
permitting them to sit in a position of comfort
upon the parent’s lap.
 Children younger than 6 years of age:
epiglottitis undergo endotracheal intubation
 Older children and adults: severe respiratory distress
(eg, stridor, drooling, sitting erect, cyanosis) or >50 %
obstruction of the laryngeal lumen endotracheal
intubation
ACUTE EPIGLOTTITIS CONTD..
• Patient not able to maintain airway
• Bag-valve-mask ventilation
• Oxygenation not maintained
• Immediately attempt to place an oral endotracheal
• Emergency surgical airway varies by age
• < 12 years of age, perform needle cricothyroidotomy
• In older patients, perform surgical cricothyroidotomy
 Antimicrobial therapy
 Racemic epinephrine
 Bronchodilators and parenteral glucocorticoids
CROUP
• A respiratory illness characterized by inspiratory stridor, barking
cough, and hoarseness.
• Result from inflammation in the larynx and subglottic airway
• Viral croup (classic croup) refers to the typical croup syndrome that
occurs commonly in children 6 months to 3 years of age.
• The anatomic hallmark of croup is narrowing of the subglottic airway.
CROUP CONTD..
• The cricoid cartilage of the subglottis is a complete cartilaginous ring.
• The cricoid cannot expand, causing significant airway
narrowing whenever the subglottic mucosa becomes
inflamed.
• Dynamic obstruction of the extrathoracic trachea below the
cartilaginous ring may occur when the child struggles, cries, or
becomes agitated.
CROUP CONTD..
Imaging
• Radiographic confirmation is not required
• Indication:
• If the diagnosis is in question,
• Atypical course
• An inhaled or swallowed foreign body is suspected
• Croup is recurrent,
• There is a failure to respond as expected to therapeutic
interventions.
CROUP CONTD..
• Findings
• In children with croup, a posterior-anterior chest
radiograph demonstrates subglottic narrowing,
commonly called the "steeple sign“.
• The lateral view may demonstrate over distention of
the hypopharynx during inspiration and subglottic
haziness.
CROUP CONTD..
 Initial treatment of moderate to severe croup includes administration of
dexamethasone and nebulized epinephrine.
 Also receive supportive care including humidified air or oxygen,
antipyretics, and encouragement of fluid intake
 Dexamethasone (0.6 mg/kg, maximum of 16 mg)
Some Other Causes
 Bacterial Tracheitis
 Retropharyngeal Abscess
 Peritonsillar Abscess
 Laryngeal Papillomatosis
Chocking
•
•
•
•
Airways obstruction by a foreign body.
Recognition of chocking is important.
Look for signs of chocking.
Assess severity.
Chocking cntd..
 Small children often choke on food or small objects and usually
clear the obstruction spontaneously with coughing and choking.
 Only about 2% of FB aspiration cases need an intervention.
 Complete airway obstruction (ie, is unable to speak or cough),
dislodgement using back blows and chest compressions in infants,
and the Heimlich maneuver in older children, should be attempted.
Recognition of FBAO
Heimlich Maneuver- place your fist on the patient’s midline
between the waist and rib cage. Grasp the fist and rapidly
deliver four upwards thrusts.
For a complete airway obstruction
In an infant, alternate back blows & chest thrusts
Chest thrust
TRAUMA
• Blunt or penetrating injury to various anatomic structures may result
in upper airway obstruction.
• Traumatic injury to the face may cause soft tissue swelling
or hemorrhage, leading to airway compromise.
BURN INJURIES
• Facial burns or burnt facial hairs should alert the
possibility of thermal injuries to the upper airway.
• Despite no initial airway compromise, edema can rapidly
progress.
ANAPHYLAXIS
• May be severe and life-threatening when
edema involves the retropharynx and/or larynx.
• Usually sudden onset of symptoms and there may be
associated signs such as urticaria and facial swelling.
• Emergent treatment can be life-saving.
ANGIOEDEMA
• Laryngeal edema occurs in approximately ½ of all
patients with inherited angioedema at their
lifetime.
• Tooth extraction and oral surgery are common triggers
for laryngeal attacks.
LARYNGOSPASM
• An acute manifestation of vocal cord dysfunction that
is usually precipitated by irritation of the vocal cords.
• The symptoms of vocal cord dysfunction (VCD) are
usually chronic.
• The acute onset or worsening of stridor from VCD can be
alarming and this is particularly true when the VCD is
due to a lesion in the brainstem.
• Hypocalcemic tetany is a rare cause of laryngospasm.
DECREASED OROPHARYNGEAL
MUSCLE TONE
• The tongue can fall back into the pharynx and obstruct
the airway in children with decreased oropharyngeal
muscle tone as can occur with depressed levels of
consciousness or neuromuscular disease (eg, cerebral
palsy, congenital myopathies, or cranial neuropathy).
• Simply repositioning the airway may relieve the
obstruction.
• Persistent obstruction may be treated with a
nasopharyngeal airway in the conscious or
semiconscious patient.
AIRWAY SECRETIONS OR
BLEEDING
• Oropharyngeal or nasopharyngeal bleeding and
secretions can cause significant upper airway
obstruction in children.
• Superficial suctioning of the naso- and oropharynx
and, as needed, control of bleeding resolves the
obstruction.
Congenital causes of upper
airway obstruction
•
•
•
•
•
•
•
Laryngomalacia
Subglottic stenosis
Choanal atresia
Laryngeal web
Laryngeal cyst
Vocal cord paralysis
Vascular ring developmental anomaly of aorta
Bronchoscopy
A technique of visualizing the inside of the airways for
diagnostic and therapeutic purposes by using a
bronchoscope.
2 types of bronchoscopy :
 Rigid
 Flexible fibre optic
Rigid bronchoscope
Rigid bronchoscopy
Indications:
A) Diagnostic
 To find the cause of wheezing, haemoptysis, or
unexplained cough for more than 4 weeks.
 When X-ray chest shows:
-Atelectasis of a segment, lobe or entire lung
-Localised opacity of a segment or lobe of lung
-Obstructive emphysema –to exclude foreign body.
-Hilar or mediastinal shadows.
 Vocal cord palsy
 Collection of bronchial secretions
-for culture and sensitivity tests, acid fast bacilli,
fungus, malignant cells.
2)Therapeutic
1. Removal of foreign bodies.
2.Removal of retained secretions or mucus plug.
-in cases of head injuries, chest trauma, thoracic
or abdominal surgery or comatosed patients.
Contraindications:
• Absolute – inability to adequately oxygenate the
patient during procedure
• Coagulopathy or bleeding diathesis that cannot be
corrected.
• Rigid bronchoscopy - Aneurysm, marked kyphosis.
• Recent MI or unstable angina.
• Respiratory failure requiring mechanical ventilation.
Technique
1.Anaesthesia
General anaesthesia with no endotracheal tube or
with only a small bore catheter.
2.Position (Barking-dog position)
Patient lies supine
Head is elevated by 10-15 cm by placing a pillow under
the occiput.
Neck is flexed on thorax and head is extended on
atlanto-occipital joint.
Methods to introduce bronchoscope:
• Direct method
–directly through the glottis
• Through laryngoscope
-glottis exposed with a spatular type laryngoscope
-the bronchoscope is introduced through the laryngoscope
-laryngoscope withdrawn.
-Infants, young children, adults-short neck & thick tongue.
Procedure
•
A piece of gauze is placed on the upper teeth to avoid injury.
•
Proper-sized bronchoscope is lubricated with a swab of autoclaved
liquid paraffin or jelly. Held by the shaft in the right hand in a pen-like
fashion. Retract the upper lid and guide the bronchoscope with left
hand.
•
Look through the scope, identify the tip of epiglottis and pass the
scope behind it. The epiglottis lifted forward to expose the glottis.
Rotate the scope 90˚ clockwise so that the tip is in the axis of
glottis. Once the trachea is entered, scope is rotated back to the
original position.
•
Gradually advanced the scope and the tracheobronchial tree
examined. Axis of bronchoscope should correspond with axes of
trachea and bronchi.
•
Direct vision, right angled and retrograde telescope can be used
for magnification and detailed examination.
•
Biopsy of the lesion of suspicious area can be taken.
•
Secretions can be collected for exfoliative cytology, or
bacteriologic examination.
Post-operative care
Keep patient in humid atmosphere
Watch for respiratory distress
-due to laryngeal spasm or subglottic oedema if the
procedure had been unduly prolonged or repeated
introduction of bronchoscope.
-inspiratory stridor and suprasternal retraction
will indicate need for tracheostomy.
Complications
Injury to the teeth
Hemorrhage from the biopsy site
Hypoxia and cardiac arrest
Laryngeal oedema
Precautions during bronchoscopy
Select proper size
Do not force through closed glottis
Repeated removal and introduction should be avoided
Should not be prolonged >20 min. in infants and children
Flexible fibre optic bronchoscopy
 Provides magnification and better illumination.
 Smaller size –permits examination of subsegmental
bronchi.
 Easy to use in patients with neck or jaw abnormalities.
 Can be performed under topical anaesthesia & useful
for bedside examination of critically ill patients
 suctions/biopsy channel provided helps to remove
secretions, inspissated mucus plug and small foreign
bodies.
 Can be easily passed through endotracheal tube or in
tracheostomy opening.
Flexible fibre optic bronchoscopy
Limited utility in children –problem of
ventilations
ASA DIFFICULT AIRWAY
ALGORITHM
Basics
Evaluation of the
Airway
Informing the
patient/Bystander
Availability of a
Trained Assistant
Availability of
equipment
Optimise the
position /
Preoxygenation
Assess the basic management
problems
• Difficult
supraglottic
airway
placement
•Difficulty
with patient
cooperation
or consent
• Difficult
mask
ventilation
•Difficult
intubation
• Difficult
laryngoscopy
•Difficult
surgical
airway access
Consider the basic management
choices
• Awake Intubtn vs. Intubtn after
induction of GA
• Non-Inv. vs. Inv. Techniques initial
approach
•
Video Assisted Laryngoscope as an
initial approach to intubation
• Preservation vs. ablation of spont.
ventilation
Throughout the process of
difficult airway
 Actively deliver supplemental
OXYGEN
Develop primary and alternative
strategies
AWAKE INTUBATION
INTUBATION AFTER INDUCTION OF GA
AWAKE INTUBATION
Airway approached by
NON Invasive Airway Access
Succeed
Invasive Airway
Access
Fail
Cancel
case
Invasive
airway access
Consider feasibility of
other options
INTUBATION AFTER INDUCTION OF GA
INITIAL INTUBATION
UNSUCCESSFUL
FROM THIS POINT ONWARDS
CONSIDER
INITIAL INTUBATION ATTEMPTS
SUCCESSFUL
.
1.CALL FOR HELP
2.Return to spont ventilation
3.Awaken the patient
INITIAL INTUBATION ATTEMPTS
UNSUCCESSFUL
FACE MASK VENTILATION
ADEQUATE
FACE MASK VENTILATION
NOT ADEQUATE
FACE MASK VENTILATION ADEQUATE
NONEMERGENCY PATHWAY
Ventilation adequate, intubation unsuccessful
Alternative approaches to intubation
SUCCESSFUL
INTUBATION
INVASIVE AIRWAY
ACCESS
FAIL AFTER MULTIPLE
ATTEMPTS
CONSIDER FEASIBILTY OF
OTHER OPTIONS
AWAKEN THE
PATIENT
FACE MASK VENTILATION NOT ADEQUATE
CONSIDER/ATTEMPT SGA
SGA NOT ADEQUATE OR NOT FEASIBLE
SGA ADEQUATE
EMERGENCY PATHWAY
Ventilation not adequate, intubation unsuccessful
Call for help
Emergency NON invasive airway ventilation
Successful ventilation
Invasive airway access
Consider feasibility of other options
FAIL
Emergency invasive airway access
Awaken the patient
From: Practice Guidelines for Management of the Difficult Airway:An Updated Report by the American Society of Anesthesiologists Task Force
on Management of the Difficult Airway
Anesthesiology. 2013;118(2):251-270. doi:10.1097/ALN.0b013e31827773b2
Follow-up Care
 Extuabation strategy
 Postextubation care and counselling
 Documentation of a difficult airway
 Registration with
notification
service
Take Home Message
 Patients with airway obstruction are high risk; they should be managed by
senior anaesthetic and surgical staffs that have good technical and nontechnical skills.
 There is no universal ‘best approach’ with experts often providing differing
opinions on optimal management.
 The best outcomes are achieved by the right personnel using equipment
with which they are familiar and skilled, at the right time, and in the right
location.
 Holding measures are often useful, allowing time to assemble team
members, gain further information, and plan airway intervention.
 Oxygen delivery utilising high-flow nasal cannula is revolutionising airway
management and should be available.
 Flexible bronchoscopy is a standard of care for specific indication .
However ,alternative techniques need to be considered.
References
 Wong P, Wong J, Mok MUS. Anaesthetic management of acute
airway obstruction. Singapore Med J. 2016;57(3):110.
 Lynch J, Crawley SM. Management of airway obstruction. BJA
Educ. 2018;18(2):46.
 Bryant H, Batuwitage B. Management of the Obstructed Airway.
2016
 Diseases of Ear,Nose and Throat And Head and Neck surgery ,
PL Dhingra, Shruti Dhingra. 6th Edition.
MODERATOR
DR. BISHAL GURUNG
LECTURER
DEP. OF ANAESTHESIOLOGY , PAHS
Thank you !
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