CSF Leak Repair

Often performed via endoscopic sinus approach for spontaneous leak with rhinorrhea

•  Usually requires intrathecal injection of fluorescein (aids in localization under FESS)

•  May place lumbar drain for 48- to 72-hr postop CSF drainage

•  CSF opening pressure may be of prognostic utility

•  Surgeon may request periop meningococcal meningitis prophylaxis (e.g., ceftriaxone)

Microdirect/Suspension Laryngoscopy

•  Performed by otolaryngologist for a range of indications

•  Employs specialized laryngoscopes for exposure of anatomy/pathology

•  May use robot-assisted techniques & laser devices

•  Procedure is highly stimulating for relatively brief periods

•  Pts often have difficult airways & significant comorbidities

Indications

•  Tumors of larynx, oral cavity, pharynx, hypopharynx

• Biopsy, laser ablation, robot-assisted micro-resection

•  Vocal cord surgery

• Resection of vocal cord polyp

• Vocal cord injection for cord paralysis

• Insertion of mechanical larynx (artificial voice box)

•  Tracheal stenosis—dilation/ablation of lesions

•  Laser ablation/direct chemotherapy of papilloma

Special Considerations

•  Preop discussion with surgeon regarding airway management

•  Potentially difficult airway

• Prior surgery with scarring or postradiation changes (immobile larynx)

• Supraglottic/laryngeal masses or tracheal abnormalities

• Friable tissue → bleeding

•  Positive-pressure mask ventilation may be challenging/impossible

•  Airway = operative field & bed = rotated away

•  Anesthetic gases may leak to environment/surgeon (open system)

•  Intermittent apnea may be required for surgical access

•  ETT may distort surgical anatomy & impede surgical access

•  Laser ablation may be used (requires ↓ FiO₂)

• Use jet ventilation, apneic technique or laser tube

• Fill laser tube balloons with methylene blue saline

• Use airway fire protocol

•  Surgeon may desire spontaneous ventilation (assess vocal cord movement)

•  Intense but fleeting/intermittent stimulus

• Requires constant communication between surgeon & anesthesiologist

Anesthetic Management

•  GA usually indicated (owing to intense procedure stimulus)

•  Sedation & spontaneous ventilation in selected cases (with cooperative pts)

• Requires anxiolysis & extensive topicalization with local anesthetic

•  Anesthesiologist often induces GA & shares airway management with surgeon

• Surgeon should be present prior to induction of anesthesia

•  Airway management includes a variety of options

• ETT (e.g., 5.0–6.0 mm ID) placed under laryngoscopy

• Catheter for subglottic jet ventilation placed under direct visualization (see text box, page 21–5) or jet via specialized laryngoscope

• Intermittent apnea with mask ventilation

• Airway device (if used) may be periodically removed for surgical access

•  TIVA technique preferable to inhaled agent

• ↓ OR contamination with inhalation gas

• More consistent depth of anesthesia

• Propofol & titratable, short-acting narcotic often used

•  Muscle relaxation must be individualized for each case

• Consider airway management, operating conditions, need for spontaneous ventilation

• Inhalational induction may be considered

Medialization Thyroplasty (Vocal Cord Medialization)

•  Procedure performed to treat vocal cord paralysis/bowing

•  Partial resection of thyroid cartilage & prosthesis placement

Special Considerations

•  Pt cooperation = important component

•  Anesthesia best provided with sedation & local injection

• Pt able to phonate on command during surgery

• Vocal cord movement observed under nasopharyngeal laryngoscopy

• Surgical incision similar to partial thyroidectomy

• Dexmedetomidine infusion is an excellent option for cooperative sedation

PROCEDURES ON THE INNER EAR AND MASTOID

Stapedectomy

•  Usually light sedation with local anesthesia (GA for selected pts)

•  Sedation allows for intraop testing of hearing acuity

•  Titrate meds (fentanyl, midazolam, propofol, dexmedetomidine) to allow pt cooperation

•  Excessive sedation may lead to disinhibition & movement (precludes safe operating under the microscope)

•  Some centers are investigating use of pt-controlled sedation

Myringotomy Tube Placement (Placement of Ear Tubes)

•  Very short procedure, usually performed in pediatric pts under mask GA

•  IV access not necessary; can use IM analgesics (ketorolac & fentanyl)

TONSILLECTOMY/PAROTIDECTOMY/UVULOPALATOPHARYNGOPLASTY

Tonsillectomy and Adenoidectomy

Indications

•  Recurrent infection

•  Obstructive sleep apnea due to hypertrophic tonsillar/adenoid tissue

Special Considerations

•  Potential for difficult mask/airway—particularly in adults

•  Consider oral RAE tube, secure in midline

•  Procedure usually indicated owing to recurrent infection

• May be semiurgent even in the setting of active infection

•  Short procedure necessitates careful use/titration of muscle relaxants

•  Surgeon removal of mouth gag may result in extubation—monitor closely

•  “Bring back” tonsil for bleeding common

• Aggressive preinduction volume resuscitation (esp pediatric patients)

• RSI or plan for potentially difficult airway (blood in airway & edema)

• Pediatric patients with sleep study evidence of recurrent hypoxemic episodes may demonstrate increased sensitivity to opiate therapy

• Exogenous opiate requirements to provide effective postop analgesia may be reduced by up to ½ normal per kilogram dosing

• Consider scheduled titration of opioids and extended cardiopulmonary monitoring (including possible overnight admission to monitored, inpatient unit) to increase effective surveillance of postop respiratory events

Parotidectomy

•  GA with ETT; consider nasal RAE if deep lobe is to be resected

• Nasal tube precautions (oxymetazoline to nares, gentle dilation, tube sizing)

• Always a risk of significant bleeding with nasal tube placement (afrin & lubricant)

•  Facial nerve monitoring; avoid additional muscle relaxation after induction

Uvulopalatopharyngoplasty (UVA)

•  Performed for treatment of obstructive sleep apnea

•  Airway management: Mask ventilation/intubation may be difficult

•  Review sleep study results—apnea/hypopnea index for severity

•  Consider RAMP positioning for obese patients

•  Pts may require noninvasive ventilation in PACU/floor postop

TRACHEOSTOMY

Indications

•  Ventilator-dependent resp failure

•  Chronic aspiration

•  Airway tumor/injury with airway compromise

•  Acute stridor/bilateral vocal cord paralysis

Special Considerations

•  If already intubated: Vent settings, O₂ & PEEP required, intubation method & difficulty

•  If not intubated: Consider awake vs. asleep tracheostomy

•  If in resp failure/ARDS: May require special ventilator settings

• Conventional OR ventilator limited (consider ICU vent)

• Pt may not tolerate vent, disconnect (loss of PEEP)

•  May not tolerate lowered FiO₂ during electrocautery

•  Considerable bleeding is rare but possible (aberrant vasculature)

Anesthetic Management

•  Awake tracheostomy (see box, page 21–5)

•  GA: Inhalational or TIVA; muscle relaxation may optimize surgical conditions

•  Potential for ETT balloon puncture upon tracheal incision

• Deflate ETT balloon prior to tracheal incision

• Consider advancing ETT (balloon) prior to tracheal incision

• Withdrawal to just above tracheotomy site under direct surgical visualization

•  Do not fully extubate until tracheostomy is in place & secured

• If tracheostomy lost, ETT can be quickly readvanced distal to tracheotomy

•  Lower FiO₂ (<30%) if monopolar cautery to be used after tracheotomy

Management of Existing Tracheostomy

•  Does tracheostomy have a balloon/cuff?

•  Will positive-pressure vent be required? (Limited with uncuffed tracheostomy)

•  Will unusual positioning be required?

•  Is tracheostomy <7 d old?

Management of Mature Tracheostomy (>7 d)

•  Suction existing cannula

•  Denitrogenate with 100% O₂ via tracheostomy

•  Controlled inhaled induction with potent agent (e.g., sevoflurane) or IV induction

•  Exchange tracheal tube with a lubricated, wire-reinforced ETT that has the same inner diameter or one size smaller than tracheostomy tube

•  Advance tube such that black markings are positioned at stoma & check for bilateral breath sounds

•  Replace tube with clean tracheostomy tube at case completion after resumption of spontaneous ventilation if uncuffed trach

Management of Fresh Tracheostomy

•  Fresh tracheostomy (<7–10 d) requires interdisciplinary management

•  Should generally not be removed outside OR (no tract)

•  Fresh tracheostomy dislodgement = surgical emergency

• Call for surgical support & fiberoptic bronchoscope

• Put sterile gloves on & plug tracheostomy site with finger

• Do not attempt blind replacement of tracheostomy

• Risk of subcutaneous placement, bleeding, & trauma

• Attempt mask ventilation

• Place LMA if failed/difficult mask ventilation

• Attempt intubation across tracheostomy site by laryngoscopy

• Consider fiberoptic intubation if unsuccessful

• Advance ETT balloon past tracheotomy

• If intubation fails & ventilation is adequate, proceed to OR

• Tracheostomy replacement via trans-LMA fiberoptic or videolaryngoscopic guidance may be considered in stable clinical circumstances with experienced personnel

• If above efforts fail, surgical reexploration at bedside

PROCEDURES IN OPHTHALMOLOGY

Special Considerations

•  Extremes of age (pediatrics—strabismus repair) (geriatrics—cataract surgery)

•  Many ophthalmologists perform regional blocks themselves

•  Complications from movement may result in blindness

•  Appropriate precautions (see above) for laser surgery

•  Access to airway is limited during surgery

Special Medications in Ophthalmologic Population

•  Echothiophate for glaucoma

• Acetylcholinesterase inhibitor → prolongs action of succinylcholine

• Systemic effects include bronchospasm, bradycardia, hypertension

•  Sulfur hexafluoride gas for retinal detachment

• Pt may have intravitreal gas bubble up to 21 d postop

• Avoid N₂O due to potential for catastrophic air expansion

•  Consider avoidance of succinylcholine in selected circumstances

• Globe injury → increased intraocular pressure with fasciculation (succinylcholine is not absolutely contraindicated)

• Prolonged contracture of ocular musculature after dosing may interfere with forced duction test (FDT) in strabismus surgery

•  Pilocarpine & carbachol

• Drugs that promote efflux of aqueous humor by producing miosis

• Parasympathomimetics (cholinergic agonist)

• Systemic effects = parasympathetic effects (bradycardia)

•  Epinephrine

• Systemic effects may lead to tachycardia/angina

•  Acetazolamide

• Carbonic anhydrase inhibitor

• Systemic effects include metabolic acidosis, hypokalemia, ↓ ICP

•  Timolol

• β-blocker

• Systemic effects include bradycardia, hypotension, bronchospasm

•  Oral glycerol side effects: Nausea, vomiting, hyperglycemia

•  Mannitol side effects: Volume overload, renal failure

Cataract Surgery: Clear Corneal Phacoemulsification

•  Pts often elderly with multiple comorbidities

•  Procedures usually <1 hr

•  Anesthetic goals

• Akinesia of the eye & eyelid; adequate analgesia & pt cooperation avoidance of oculocardiac reflex

•  Sedation with regional block or topicalization = preferred method

• Local infiltration with sedation

• Regional block with local infiltration & sedation (see table below)

• Provided by surgeon or anesthesiologist

• Brief deepening of anesthesia facilitates block placement

• Options include retrobulbar block; peribulbar block, subtenon’s block

• Block complications: Retrobulbar hemorrhage, globe perforation, optic nerve damage, brainstem anesthesia

• GA for selected pts (complex procedures/unable to cooperate or stay supine)

Strabismus Surgery

•  Indication: Reposition muscles to treat ocular malalignment

•  Surgery almost exclusively performed in pediatric pts

•  ↑ Incidence of postop nausea & vomiting

•  ↑ Risk of intraop oculocardiac reflex (see box below)

•  Usually performed under GA with ETT

•  Nondepolarizing muscle relaxation may aid diagnostic utility of FDT & surgical operating conditions

Other Procedures

•  Repair of ruptured globe

• Frequently emergent procedure with aspiration risk concerns (full stomach, head & associated injuries)

• Commonly requires GA with ETT

• Consider LMA in select circumstances (pts often have full stomach)

• Emphasis on control of intraocular pressure (succinylcholine may ↑ IOP)

• Avoid coughing or bucking during induction & intubation

•  Intraocular surgery: Enucleation, vitrectomy, corneal transplantation, glaucoma decompression, repair retinal detachments

• Control of eye movement & intraocular pressure critical

• GA preferred

• Intraocular epinephrine may be used to aid papillary dilatation

• Monitor for systemic effects

•  Detachment repair injects intraocular air or sulfur hexafluoride gas

• Avoid N₂O or discontinue well before injection

• Avoid N₂O for subsequent surgery within 3 wks

Peribulbar Block (25–27 gauge, 25 mm needle)

•  Safer (needle inserted outside of extraocular muscle cone), but slower onset

•  Primary gaze position → 2 injections above & below globe

Inject ≈5 mL local into superonasal orbit & ≈5 mL inferotemporally between lateral ¹⁄³ & medial ²⁄³ of lower orbital margin

Retrobulbar Block (25–27 gauge, 3 cm needle)

•  Faster onset; must anesthetize conjunctiva before needle introduction

•  Insert needle halfway between lateral canthus & lateral limbus in lower conjunctiva

•  Direct needle straight back until the tip is beyond globe, → then direct needle toward apex of orbit to enter space behind globe between inferior & lateral rectus muscles

•  Insert to depth of 25–35 cm; inject 4 mL local

Subtenon’s Block (25 gauge needle)

•  Injection of local anesthetic directly into posterior aspect of subtenon’s space

•  Insert needle to contact conjunctiva between eyeball & semilunaris fold (depth <1 mm)

Advance needle anteroposteriorly with globe directly slightly medially by needle until “click” is felt, at a depth of 15–20 mm (episcleral location)

•  Return globe to primary position; aspirate → inject local

•  Stop at sign of chemosis (conjunctival edema) & apply ocular compression