1. Airway Management <<Laryngeal Mask Airway>>
In the name of Lord
Airway Management <<Laryngeal Mask Airway>>
Mehdi Hadavi MD.
Anesthesiologist

2. Airway management Knowledge Anatomy
Airway Assessment
History
Examination
Decision making History (Snoring , sleep apnea, dysphony,previous anesthesia records. . .)
Examination (Inspection(obesity-brace-trauma-infection-Anomaly), Mandible,
Teeth, Mouth and tongue, Neck (mass-mobility-size-form) )
Other Evaluations (Indirect Laryngoscopy or streboscopy ,Neck Radiography
,Chest X Ray ,CT-MRI ,PFT)
Manual skills Which way is the safest method?
Which way is possible?

3. Signs, Symptoms and Disorders with Airway Management Implications
History related to airways problem
Aspiration risk
History of voice changes /History of vocal cord polyps /History of frequent pneumonias /Coughing after eating or drinking /Acute
narcotic therapy /
Acute trauma /Intensive care unit admission (current) /Pregnancy (gestational age ≥12 weeks) /Immediate postpartum (before second postpartum
day) /
Systemic disease associated gastroparesis (diabetes mellitus, postvagotomy, collagen vascular disease, Parkinson disease, thyroid dysfunction, liver
disease, CNS tumors, chronic renal insufficiency)
Difficult laryngoscopy/ventilation
History of surgical manipulation in or around the airway /History of radiation therapy of the head/neck /Various congenital and acquired syndromes
Obstructive sleep apnea
Body mass index >35 kg/m2 (indicative) /Loud snoring /Pauses in breathing during normal sleep /Sleep interruption (with choking) /Daytime
somnolence/napping /Airway affecting craniofacial abnormalities
Lingual tonsil hyperplasia/supraglottic cyst or tumors
Chronic sore throat /Globus sensation /Voice change /Dysphagia /Obstructive sleep apnea /History of tonsillectomy (controversial)
Thyroglossal duct cyst
Asymptomatic anterior cervical mass that moves with deglutination /Complications: cysts infection, fistula, spontaneous rupture, voice change,
dysphagia, dyspnea, and snoring
Signs and symptoms related to the airway
Snoring /Changes in voice /Dysphagia /Stridor /Bleeding /Cervical spine pain or limited range of motion /Upper extremity neuropathy /
Temporomandibular joint pain or dysfunction
Sequelae of previous intubation
Chipped teeth /Significant prolonged sore throat or mandible after a previous anesthetic

4. Techniques of Common Airway Indexes Measurement
Thyromental distance: Measured along a straight line from tip of mentum to thyroid notch in neck-extended position
Mouth opening: Interincisor distance (or interalveolus distance when edentulous) with the mouth fully opened
Mallampati score
Head and neck movement: The range of motion from full extension to full flexion
Ability to prognath: Capacity to bring the lower incisors in front of the upper incisors
Sensitivity and Specificity of Commonly Used Methods of Airway Evaluation
EXAMINATION
SENSITIVITY (%)
SPECIFICITY (%)
Mallampiti classification 49 86
Thyromental distance 20 94
Sternomental distance 62 82
Mouth opening 46 89

7. Laryngeal Mask Airway

8. LMA Overview A supraglottic airway device
Developed by British Anesthesiologist Dr. Archi Brain(1988).
Initially designed for use in the operating room
A good alternative to bag-valve-mask ventilation
Recently come into use in the emergency setting as an important accessory device for management of the difficult airway.
Designed to sit in the patient’s hypopharynx and cover the supraglottic structures, thereby allowing relative isolation of the trachea.
The LMA is a good airway device : the operating room,
the emergency department, and
out-of-hospital care,
easy to use and quick to place, even for the
inexperienced provider
less gastric distention than with bag-valve-mask ventilation
but does not eliminate the risk of aspiration

9. LMA Types The LMA Classic The LMA Unique
The LMA Fastrach, /intubating LMA (ILMA)
The LMA Flexible
The LMA ProSeal
The LMA Supreme, is similar to the ProSeal and has a built-in bite block.[8]
LMA CTrach, LMA Fastrach that has built-in fiberoptics with a video screen

10. LMA Indication Elective ventilation Difficult airway Cardiac arrest
Acceptable alternative to mask anesthesia in the operating room.
Short procedures(<60 min) when endotracheal intubation is not necessary
ASA physical status 1 or 2 patients
Spontaneously breathing patients
Patients in the supine position
Lithotomy position without Trendelenburg for brief procedures (<30 minute duration)
Difficult airway
After failed intubation, the LMA can be used as a rescue device /Patient who cannot be intubated but can be ventilated /Patient who cannot be intubated or ventilated
Cardiac arrest
The 2005 AHA guidelines indicate the LMA as an acceptable alternative to intubation for airway management in the cardiac arrest patient (Class IIa).
Conduit for intubation
The LMA can be used as a conduit for intubation, particularly when direct laryngoscopy is unsuccessful.
An ETT can be passed directly through the LMA or ILMA. Intubation may also be assisted by a bougie or fiberoptic scope.
Prehospital airway management
Useful in the prehospital setting
In patients in whom positioning or prolonged extrication does not allow for endotracheal intubation
Pediatric use
Special applications of the laryngeal mask airway.
Opera singers/rock stars/public speakers
Thyroid surgery (check recurrent laryngeal nerve function)
Difficult airways (Brain 1995)
"Second-last-ditch" airway (Benumof 1996)
Awake procedures in the prone position

11. LMA Insertion Weight, kg Mask Size Max Cuff Volume, mL LMA Models
< 5 1 4
Classic, Unique
5-10
1.5 7
10-20 2 10
20-30
2.5 14
30-50 3 20
Classic, Unique, Fastrach
50-70 30
70-100 5 40
>100 6 50
Classic

12. LMA (ILMA) Insertion

13. LMA Assessment of Function of the Laryngeal Mask Airway
Observation of airway pressure and chest movement with a manual
ventilation
Reservoir bag refill during expiration
Capnograph
Auscultation over the neck
Cuff leak pressure
Expired tidal volume and flow-volume loop
Examination with a flexible fiberoptic laryngoscope

14. LMA Complication Gastroesophageal reflux and Aspiration Laryngospasm
Coughing
Gagging, Retching
Bronchospasm,
Sore throat
Hoarseness /Dysphagia
Transient changes in vocal cord
Recurrent, Hypoglossal and Lingual nerve palsy
Mild sympathetic response
Complications associated with positive pressure ventilation
Pulmonary edema
Bronchoconstriction

15. LMA Contraindication
Absolute contraindications (in all settings, including emergent)
Cannot open mouth(<1.5 cm)
Complete upper airway obstruction
Relative contraindications (in the elective setting)
Increased risk of aspiration
full stomach, hiatus hernia with significant gastroesophageal reflux, intestinal obstruction, delayed gastric emptying, poor history
Prolonged bag-valve-mask ventilation
Morbid obesity
Second or third trimester pregnancy
Patients who have not fasted before ventilation
Upper gastrointestinal bleed
Suspected or known abnormalities in supraglottic anatomy
Need for high airway pressures (in all but the LMA ProSeal, pressure cannot exceed 20 mm H2 O for effective ventilation.)
poor lung compliance
high airway resistance