Airway Management Flashcards
Indications for airway management
Intubation is indicated for patients at risk for aspiration and those undergoing surgical procedures involving body cavities or the head&neck.
Mask ventilation or LMA are sufficient for short minor procedures like cystoscopy and inguinal hernia repair
Techniques for airway management
Jaw thrust and chin lift to open airway. Artificial airway inserted in mouth or nose. Alignment of 3 axis's: oral, pharyngeal, laryngeal (flexion of lower cervical spine ~35degrees and extension of upper cervical spine ~80 degrees). Face mask ventilation. ETT Esophageal-tracheal combitube Nasotracheal intubation Flexible Fiberoptic Nasal intubation
Describe how to evaluate the airway
- Mouth opening at least 2 large finger breadths
- oropharynx: Mallampati classification and Largyngoscopy grade
- Thyroid - mandibular distance: greater than 6cm, 3fingers
- TMJ subluxation - 1 finger
- Neck Mobility
Mallampati classification
Class I - soft palate, all uvula, fauces, anterior and posterior tonsillar pillars
Class II - soft palate, fauces, part of uvula
Class III - soft palate, base of uvula
Class IV - hard palate only
Laryngoscopy grade
a. Grade I: complete glottis visible
b. Grade II: anterior glottis NOT seen
c. Grade III: epiglottis seen, but not glottis
d. Grade IV: epiglottis NOT seen
Nerve to mucous membrane of nose
ophthalmic division V1 anteriorly (anterior ethmoidal n.) and maxillary division V2 posteriorly (sphenopalatine n.)
Tongue sensation innervation
Lingual n. (branch of V3) and glossopharyngeal n.
Tongue taste innervation
VII and glossopharyngeal n.
Roof of pharynx, tonsils, undersurface of soft palate innervation
glossopharyngeal n.
Sensation to airway below epiglottis innervation
vagus n.
Larynx below vocal cords and trachea innervation
recurrent laryngeal n.
cricothyroid m. innervation
external laryngeal n. (branch of superior laryngeal n.)
Superior Laryngeal nerve injury
If unilateral - minimal effect
If bilateral - hoarseness, tiring of voice, but airway control NOT jeapardized
Recurrent Laryngeal nerve injury
If unilateral - hoarseness
If bilateral - acutely: stridor, respiratory distress (because unopposed tension of cricothyroid m. innervated by intact superior laryngeal n.). Chronic - aphonia = cant speak, less frequent airway problems because of compensation (atrophy of laryngeal musculature)
Vagus nerve injury
If unilateral - hoarseness
If bilateral - aphonia, but airway control rarely a problem
Causes of difficult mask ventilation
poor mask fit, short neck, obesity, lack of teeth, facial distortion, airway/neck or mediastinal mass, radiation therapy to airway or neck, multiple intubation attempts, airway trauma
Causes of difficult intubation
short neck, receding mandible, prominent upper incisors, narrow/high arched palate, limited mouth opening; macroglossia, cleft palate, vascular compression, various syndromes; RA (cervical instability, cervical fusion), temporomandibular dz, cricoarytenoid fibrosis, radiation to head and neck; infxn/neoplasms – retropharyngeal abscess, epiglottis, laryngeal tumors, cystic hygroma, mediastinal masses; acromegaly; trauma
What to do if can’t intubate
reestablish mask ventilation, rearrange head position, try different blades, call for help, alt. techniques (mask vent, intubation assist devices, LMA, asleep fiberoptic intub), awaken pt., surgical airway
Equipment needed to support & augment ventilation
A. Laryngoscopes (Macintosh [tip insert in vallecula] and Miller [cover epiglottis]), endotracheal tubes, stylet, syringe for balloon, O2, ambu bag, mask, suction, monitors (SpO2 & EtCO2), assistant,
Flexible fiberoptic bronchoscopes (FOB)
How to identify upper airway obruction in unconscious patient
high breathing-circuit pressures w/ minimal chest mvt and breath sounds
Ways to relieve obstruction in unconscious patient
- Have assistant help you so that two or three hands can be used in a jaw thrust maneuver.
- Try using an oral or nasal airway
- If due to laryngospasm, remove offending stimulus (e.g. oral nasal airway, secretions like saliva/blood/vomitus), apply continuous positive airway pressure, deepen anesthetic state and use rapid-acting m. relaxant. Don’t use sux if wheelchair bound/burns/hospitalized patients (upregulation of nicotinic receptors, therefore when sux given will get more hyperkalemic)
- Adjust and possibly reinsert tracheal tube/LMA
How to monitor adequacy of ventilation (important!)
A. Auscultation for presence bilateral breath sounds
B. Chest movement
C. EtCO2 (gold standard), SpO2
D. Fogging up of tube/mask
Physiological response to intubation
HTN and tachycardia (up to 10 min), laryngospasm caused by stimulation of superior laryngeal n., bronchospasm, increased intracranial (CNS) and intraocular P (eye), GI – regurg and aspiration.
Treat laryngospasm: O2 with continuous positive airway pressure and small dose rapidly acting m. relaxant if necessary
Common complications during intubation
hypoxia, hypercarbia, dental and airway and cervical spine trauma, tube malpositioning, tube malfunction, hemorrhage, trauma to eye, pharyngeal/tracheal dissection, esophageal intubation, aspiration gastric contents/foreign body, main stem intubation
