Ear, nose, and throat surgeries

Endoscopy

Laryngoscopy, micro laryngoscopy, esophagoscopy, and bronchoscopy.

Evaluated for hoarseness, stridor, and hemoptysis.

Consider difficult airway, discuss plans with the surgeon and his exam results from his office.

Anesthetic considerations

Goals

Muscle paralysis to provide masseter muscle relaxation, immobile surgical field, oxygenation and ventilation, and cardiovascular stability

Oxygenation and ventilation

Intubation

Small catheter via trachea for quick procedure

Intermittent-apnea technique (alternates with the surgeon, high risk of increased CO2 and aspiration -monitor O2 sat)

• Manual jet ventilator to the side port of laryngoscope (monitor for chest wall movement)

Cardiovascular stability

Cardiac disease due to alcohol/smoking

Stress-provoking procedure with intermittent stimulation

Consider regional blocks of glossy pharyngeal nerve (base of palatoglossal arch) and superior laryngeal nerve (injection 1cm below each greater cornu of hyoid bone) to minimize labile BP

Laser surgery

Light Amplification by Stimulated Emission of Radiation

Light

• Monochromatic (one wavelength)
• Coherent oscillates (repetitive variation) in the same phase
• Collimated (narrow, parallel beam)

This provides excellent precision and hemostasis with minimal post-op edema or pain

Side effects

Dependent on wavelength

• CO2 laser: long wavelength laser (10,600nm)
• YAG laser: shorter wavelength laser (1064-1320nm) YAG= yttrium-aluminum-garnet

Longer wavelength equals increased absorption by water and decreased tissue penetration; thus, the CO2 laser is superficial and localized, while the YAG laser goes deeper.

Anesthetic considerations

Wear eye protection and tape the patient's eyes.

Minimize risk of tracheal tube fire

Inspired O2 as low as possible

No N2O, but use air

The tracheal tube cuff can be filled with saline dyed with methylene blue to dissipate heat and signal cuff rupture

Cuff minimizes O2 concentration in the pharynx

Limit laser intensity and duration as much as possible.

Saline-soaked pledgets in the airway

Have water immediately available

Airway-fire protocol

Stop ventilation and remove the tracheal tube

Turn off oxygen, disconnect the circuit

Submerge tube in water

Ventilate with FM and reintubate

Assess airway damage with a bronchoscope, chest X-ray, ABGs

Consider bronchial lavage and steroids (swelling)

Nasal and Sinus surgery

Polypectomy, endoscopic sinus surgery, maxillary sinusotomy (Caldwell-Luc procedure), rhinoplasty, septoplasty.

Five major branches

Through parotid gland - from top to bottom: "To Zanzibar By Motor Car" (part of CN VII)

• Temporal (frontal) branch of the facial nerve
• Zygomatic branch of the facial nerve
• Buccal branch of the facial nerve
• Marginal mandibular branch of the facial nerve
• Cervical branch of the facial nerve

Sinuses

Frontal Sinus

Anterior ethmoidal sinuses

Middle ethmoidal sinuses

Posterior ethmoidal sinuses

Sphenoid sinus

Maxillary sinus

Anesthetic considerations

Nasal obstruction makes FM ventilation difficult

• Use oral airway

Consider RAE tube

Secure airway

Rich vascular supply

• Check for hx of bleeding/aspirin use

Tape eyes to prevent corneal abrasion

Endoscopic sinus surgery

• The surgeon may want to check for eye movement with dissection due to proximity to the orbit
  • Facial nerves
  • Spinal accessory CNXI
    • Provides motor innervation from the central nervous system to two muscles of the neck: the sternocleidomastoid muscle and the trapezius muscle

NMBD is recommended due to potential neurological or ophthalmic complications with patient movement

Local anesthetic with epinephrine to minimize bleeding and blood loss

Posterior pharyngeal pack

Minimize cough and straining on extubation while trying to prevent aspiration at the same time

Allergies (asthma/ aspirin = no Non-steroidal anti-inflammatory drugs such as Toradol

Head and neck cancer surgery

Laryngectomy, glossectomy, pharyngectomy, parotidectomy, hemimandibulectomy, and radical neck dissection.

Tracheostomy depends on the patient's status.

Possible reconstruction surgery with muscle flap.

Anesthetic considerations

Elderly, hx of smoking/alcohol/COPD, CAD

Secure airway after thorough evaluation (iv-induction-fiberoptic laryngoscopy-inhalational induction-tracheostomy)

May place tracheostomy after induction and intubation (dissection down to trachea, deflate the cuff, pull ETT tube cephalad to incision, place the tracheal tube in trachea, confirm the position, remove ETT)

Two large bore IVs

F/C with temp monitoring

• Maintain normal temp
• Hypothermia causes vasoconstriction and subsequent less perfusion of a microvascular free flap

The surgeon may request no NMBD to identify nerves and preserve them.

• Facial nerves, spinal accessory CN XI (provides motor innervation from the central nervous system to two muscles of the neck: the sternocleidomastoid muscle and the trapezius muscle)

Compromised cerebral perfusion pressure (CCP= MAP-ICP or CVP)

• Should be >60

Note

• Vasoconstrictors will decrease flap perfusion
• Vasodilators will decrease perfusion pressures

Monitor for blood loss

Avoid diuresis to allow adequate graft perfusion postop

Manipulation of the carotid sinus and stellate ganglion can cause labile BP, bradycardia, arrhythmias, sinus arrest, and prolonged QT

• The stellate ganglion is a sympathetic ganglion formed by the fusion of the inferior cervical ganglion and the first thoracic ganglion
• The stellate ganglion is located at the level of C7 just below the subclavian artery

Dextran 40 to help with microcirculation

Maxillofacial reconstruction and orthognathic surgery

Maxillofacial: Trauma, developmental malformations, radical cancer surgery, or obstructive sleep apnea.

Orthognathic: LeFort osteotomies, mandibular osteotomies for skeletal malocclusions.

Anesthetic considerations

Thorough airway evaluation (jaw opening, mask fit, neck mobility, micrognathia (small lower jaw), retrognathia (small or recessed jaw (either the upper jaw - maxilla or the lower jaw -mandible) that may predispose to obstruction of the airway and sleep apnea), maxillary protrusion (overbite), macroglossia, dental pathology, nasal patency, any intraoral lesions or debris

RAE tube

• Secure well, as the table may turn 90 or 180 degrees

LeFort fractures

• Nasal intubation is contraindicated due to the risk of coexisting basilar skull fracture and cerebrospinal fluid rhinorrhea

Limit blood loss: slight head up, controlled hypotension, local infiltration with epinephrine

Oropharyngeal pack

If intermaxillary wiring

• Must have wire cutter at the bedside

Evaluate for edema; may need to leave the patient intubated

Ear surgery

Three bones of the inner ear

The stapes, the incus, and the malleus

Eustachian tube

Runs from the middle ear to the oral cavity and equalizes pressures in the middle ear

If it is damaged, pressure will rise in the middle ear

Types

Stapedectomy

Stapes is removed and replaced with a small plastic tube of stainless-steel wire (a prosthesis) to improve the movement of sound to the inner ear

Tympanoplasty

Reconstruct a perforated tympanic membrane (eardrum) or the small bones of the middle ear

Mastoidectomy

Surgical procedure to remove an infected portion of the bone behind the ear when medical treatment is not effective

Myringotomy and insertion of tympanostomy tubes (M&T)

History of upper respiratory infections, episodes of otitis media

Release of accumulated fluid in the middle ear

Tubes provide long-term ventilation and drainage

Anesthetic considerations

Short procedure (M&T)

Inhalational anesthesia - Sevo

FM or LMA

RAE for better access for the surgeon

Ask about NMBD - sometimes not indicated

Note N2O

• 34 times more diffusible than nitrogen, will move into closed cavities (middle ear). If in use, turn off 30min before graft placement - it is better to avoid completely
• If the middle ear is open, no pressure build-up, but once the graft has been placed, the middle ear is a closed space, resulting in rising pressures and graft dislodgement
• If N2O is discontinued after graft placement, negative pressure develops, resulting in graft dislodgement

Minimize bleeding and blood loss

• Elevate head slightly, LA with epinephrine, controlled hypotension (Map 60-70 mmHg)

Minimize cough and straining on extubation while trying to prevent aspiration at the same time

Expect nausea/vomiting

• Zofran (0.1mg/kg)
• Dexamethasone
• Reglan (0.15mg/kg)