laryngoscopy & complications

Laryngoscopy and

Complications

Presenter: Dr. Suresh PradhanModerator:Prof. Dr. UC Sharma

Laryngoscopy• Laryngoscopy (larynx + scopy) • Laryngoscopy may be performed to

Facilitate tracheal intubation during general anesthesia or CPR or

for procedures on the larynx or other parts of the upper tracheobronchial tree

• Examination of the larynx is carried out for both diagnostic and therapeutic indications.

DiagnosticDiagnostic indications for laryngoscopy include:• stridor, either congenital or acquired• subglottic stenosis• cysts or masses causing airway obstruction• vocal cord palsy• foreign bodies

TherapeuticTherapeutic indications for laryngoscopy include:• subglottic stenosis• aspiration/injection of mucous cysts, cystic

hygromas• papillomas• lingual thyroid• webs

• Laryngoscopy can be performed by using rigid or flexible instruments• each of which has certain specific advantages and

limitations

Rigid LaryngoscopyA rigid laryngoscopy may be done by using the indirect or direct method• Indirect laryngoscopy

performed by using specially designed laryngeal mirrors in combination with a headlight

enables the larynx and the nasopharynx to be visualized

frequently used in adults, but in children it is often difficult to carry out this procedure

•Direct laryngoscopy performed with handheld curved or straight blade

instruments also by using the suspension laryngoscope, which

leaves both hands free to manipulate instruments the curved Macintosh blade and the straight Miller

blade laryngoscopes are routinely used by anesthetists to intubate patients

• Suspension laryngoscope frequently carried out by ear, nose, and throat

(ENT)surgeons consists of a short tubular laryngoscope that is locked to

a supporting arm that rests on a base plate lying against the anterior chest wall

this arrangement leaves the surgeon’s hands free to use instruments

Laryngoscope with different sizes of Macintosh blades

Laryngoscope with different sizes of Miller blades

Parts of a Macintosh Blade

Parts of a Miller Blade

• decision of whether to use a Macintosh or a Millerblade is multifactorial• however, the personal preferences and experience

of the laryngoscopist is a significant consideration• In general, the Macintosh is most commonly

used for adults, whereas the straight blades are typically used in pediatric patients

Preparation for Direct Laryngoscopy• proper patient positioning,• adequate pre-oxygenation, and • the availability and proper functioning of all

necessary equipment like • laryngoscopes,• tracheal tubes,• tube stylets,• an empty syringe for inflating the tracheal tube cuff• a suction apparatus, and • the essential equipment for mask ventilation, including an

oxygen source

• A skilled assistant should be present to help with external laryngeal manipulation and stylet removal

Positioning of the Patient

Figure A The head is in the neutral position. None of the three visual axes

align.

Figure B Elevation of the head produces cervical flexion, which aligns the laryngeal axis

(LA) and the pharyngeal axis (PA).

Figure C Extension at the atlanto-occipital joint brings the visual axis of the mouth into better

alignment with those of the larynx and pharynx.

Conventional laryngoscopy with a Macintosh (curved) blade

• two methods for elevating the epiglottis,depending on whether a straight or curved blade is being used.Straight blade techniqueCurved blade technique

Intubation with a straight laryngoscope blade. The tip

of the blade picks up the epiglottis.

Straight blade technique• blade is made to scoop under

the epiglottis and is lifted anteriorly. • the vocal cords should be

identified. • If the blade is advanced too

far, it will elevate the larynx as a whole rather than expose the vocal cords.

Intubation with the curved laryngoscope blade. The epiglottis is belowthe tip of the blade.

Curved blade technique• After the epiglottis is visualized blade

is advanced until the tip fits into the vallecula.

• Traction is then applied along the handle at right angles to the blade to move the base of the tongue and the epiglottis forward and upward.

• The glottis will come into view.• A curved blade can also be used as a

straight blade, lifting the epiglottis directly, if it is long enough

Flexible laryngoscopy• instruments used for flexible laryngoscopy include

the ultrathin bronchoscope, the standard flexible bronchoscope, and the specially designed flexible nasopharyngoscope

• ultrathin bronchoscope has no suction or instrument channel and is mostly used by anaesthetists for intubation in difficult head and neck cases

• the standard bronchoscope has an instrument or suction channel and can be used for therapeutic indications

• the standard flexible bronchoscope and the nasopharyngoscope are used to evaluate laryngomalacia and vocal cord paralysis

Video Laryngoscopes• Dr. John Berall, a New York

City internist and emergency physician designed a camera screen straight video laryngoscope in 1998• The first true video

laryngoscope Glidescope was produced in 1999• Was commercially available

from Dec 2000

COMPLICATIONS

1. Dental Injury• damage to teeth, gums, or dental prostheses is the

most frequent• cosmetic disfigurement and discomfort,• pulmonary complications if the dislodged

tooth or fragment is aspirated• profuse bleeding

• upper incisors are most frequently involved• condition of each patient’s teeth should be

carefully assessed preoperatively to identify possible problems• a tooth protector may be used

Tooth Protectors

2. Cervical Spinal Cord Injury• aggressive head positioning during intubation,

especially head or neck extension, has the potential to cause damage in the patient with an unstable cervical spine

3. Damage to Other Structures• reported injuries to the upper airway include• abrasion• hematoma• lips, tongue, palate, pharynx, hypopharynx, larynx,

and esophagus lacerations• Osteomyelitis of the mandible has been reported• lingual and/or hypoglossal ner ve may be injured• Arytenoid subluxation• Anterior temporo manidibular joint (TMJ) dislocation

there is a significant increase in the rate of airway related complications as the number of laryngoscopic attempts increases

4. Shock or Burn• if a laryngoscope light that is left ON contacts the

patient, a burn may result• a short circuit can result in the handle and blade

rapidly heating • the tip of a fiberscope applied directly to the skin

may produce a burn

5. Swallowing or Aspirating a Foreign Body• Cases have been reported in which the bulb or

other part of a laryngoscope was aspirated or swallowed

6. Laryngoscope Malfunction• most common laryngoscope malfunction is light

failure• a pre-use check will detect most malfunctions• an extra handle and blade should always be

immediately available/ kept ready

7. Circulatory Changes• may result in significant increases in blood pressure

and heart rate, although these changes are less than those associated with tracheal intubation

8. Disease Transmission• risk of infection

transmission, particularly Creutzfeldt-Jakob disease, via laryngoscopes, is unknown, but is a matter of concern to anesthesiaproviders • use of a disposable blade

cover or disposable laryngoscope blade has been encouraged

Thank you!!!