ENT Quiz Study Guide PDF

**[CONSIDERATIONS]** **Patient Positioning ** - Bed is often turned 90-180 degrees away from anesthesia provider - Meticulous attention to ETT placement/securement of ETT - Confirm ETT placement with every patient repositioning! - Vigilant monitoring **Controlled Hypotens...

**[CONSIDERATIONS]** **Patient Positioning ** - Bed is often turned 90-180 degrees away from anesthesia provider - Meticulous attention to ETT placement/securement of ETT - Confirm ETT placement with every patient repositioning! - Vigilant monitoring **Controlled Hypotension** - MAP is reduced to a predetermined acceptable level - [Objective:] decrease bleeding, improve surgical visualization - Not appropriate for all patients - Usually no more than 20% from baseline - Requires A-Line - Chronic HTN patients may require a higher MAP - Monitor UO, MAP, cerebral and cardiac perfusion pressure, ABGs - [Methods:] - Inhalational agents - Vasodilating agents - Beta blockers: Labetalol, Esmolol - Alpha 2 Adrenergic Agonists: Dexmedetomidine - Calcium Channel Blockers - Ultra-short acting opioids: Remifentanil - Magnesium sulfate **PONV** - ENT procedure may be associated with a higher incidence of PONV - Middle ear procedures - Pediatric strabismus  - T&A (swallowed blood can be a factor) - Multimodal approach should be utilized **[MEDICATIONS]** **Topical Local Anesthetics** - [Cocaine:] anesthetic and vasoconstrictive properties; blocks reuptake of norepinephrine and epinephrine at adrenergic nerve endings - [Lidocaine:] rapid onset and can be used in all areas of tracheobronchial tree - [Benzocaine:] short duration of action; can produce *METHEMOGLOBINEMIA (pulse ox. Stays at 85%)* - **Cetacaine** contains 14% benzocaine, 2% butamben, and 2% tetracaine - [Bupivacaine:] longer duration of action (slow hepatic clearance) - [Mepivacaine:] rapid onset, intermediate potency **Anticholinergics** - Antisialogougue to dry upper airway and decrease secretions - Improve effectiveness of topical anesthetics - Improve surgical visibility - Reduce risk of laryngospasm - Options include: - **[Atropine]** (Adult dose 0.5-1mg IM or IV) - **[Scopolamine]** (Adult dose 1mg transdermal patch) - More potent drying agent and is less likely to increase HR - Causes sedation, amnesia, and euphoria - [**Glycopyrrolate**] (Adult dose 0.2-0.4 mg IM or IV) - Better option than atropine - Less tachycardia - Does not cross BBB/ no sedative effects - Longer duration of action - Tertiary v. amine compounds will determine if anticholinergic crosses the BBB **Corticosteroids** - Used to decrease laryngeal edema and PONV - Prolong analgesic effects of local anesthetics (inhibition of prostaglandin synthesis) - [Dexamethasone] used most frequently - Administer as early as possible (preop or as soon as IV is placed in pediatric patients) **Vasoactive Drugs** - Topical vasoconstrictors are used to minimize intraoperative blood loss and optimize ventilation - Cocaine - Epinephrine containing local anesthetics **[AIRWAY MANAGEMENT]** **MLT (Microlaryngeal Tubes)** - Smaller diameter---good for vocal cord procedures  - Longer length - Adult-sized cuff - Cuff located further away from tube tip - Come in 3 sizes (4, 5, 6) - Increased airway resistance when patient is trying to spontaneously breathe after surgery  **Pre-formed RAE Tubes** - ETT with preformed bend - Adult and pediatric sizes - Labeled as a RAE tube - Cuffed and uncuffed versions - Oral (south facing) and Nasal (north facing) versions available - Oral tubes are usually taped midline to chin - No stylet used for placement - Preformed bend in RAE tube might not fit all patients well **Reenforced (Armored) Tubes** - Have embedded coil wire or plastic coil for stability - Provides increased flexibility and resistance to kinking - Good for procedures with neck flexion or where severe angles of the ETT are required - Adult and pediatric sizing available - Laser-safe versions available - Not intended for patients that remain intubated postop - Can be easily occluded if patient bites down on them **Nerve Integrity Monitoring (NIM) Tubes** - NIM= Nerve Integrity Monitoring - Allows intraop monitoring of laryngeal muscles - Precision required for placement! - Avoid excessive bending- can break the electrodes - No muscle relaxants or local anesthetics on the ETT - Not intended for postoperative use- need to change ETT if patient is to remain intubated **Laser Tubes** - Laser [resistant] ETT should be used for all airway-laser procedures - Pilot balloon cuff should be filled with saline mixed with methylene blue (not air!) - Specific tube selection depends on type of laser: - **CO2 lasers and KTP lasers** 🡪 red rubber tubes, silicone tubes wrapped in aluminum, stainless steel spiral ETT - Have a double cuffed design  - **Argon, Nd/YAG, and CO2 lasers**🡪 soft white rubber tubes wrapped in copper foil - Have a double cuff design - [No laser-safe tubes are entirely laser-proof] **LMAs---Pros and Cons ** - Less tracheal stimulation - Less coughing on emergence - NMBAs not required - Can also be used for airway rescue scenarios - Provides conduit for surgical access to trachea and glottis - [Isolates glottis from bleeding in pharynx] **[VENTILATION TECHNIQUES]** - **Standard intubation and ventilation** - Use smaller ETT or MLT (5-6) - **Advantages:** secure airway, cuff to protect lower airway from debris, ETCO2 monitoring, ability to add inhalational agents - **Intermittent Apnea** - Alternating periods of ventilation and apnea/surgeon working - The ETT is removed intermittently to allow surgeon to operate (then reinserted to resume ventilation) - Patient is mask ventilated intermittently to allow surgeon to operate then mask ventilation is resumed - **Advantages:** no special equipment needed - **Disadvantages:** potential inability to reintubate, CV lability d/t varying levels of surgical stimulation - **Insufflation** - Laryngeal procedures - Methods - Small catheter (or cut ETT) introduced into the nasopharynx and placed above the laryngeal opening - Side arm channel of the laryngoscope or bronchoscope - **Jet Ventilation** - [No ETT require/no intubation] - Can be supraglottic, infraglottic, transtracheal, or via bronchoscope - No absolute contraindications except [full stomach, trauma, hiatal hernia] - Delivers high pressure (up to 60 psi) inhalation - Exhalation is passive- must allow sufficient exhalation time to avoid air trapping, hypercarbia, and barotrauma - Can be difficult to maintain adequate oxygenation and CO2 elimination in some patients - Watch for air trapping, SQ emphysema, PTX, gastric distension, barotrauma - Environmental concern (no scavenging) - **Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE)** - Nasal high flow oxygen can be used in spontaneously breathing patients or apneic patients - Ventilation is via nasal cannula at high flow rates (10-12 L/min) - Provides humidification and warmth - [Spontaneously breathing patient:] used for preoxygenation, sedation, general anesthesia, and post extubation - High FiO2 positive airway pressure, pharyngeal dead space "washout", improved respiratory mechanics - [Apneic patient:] used to maintain oxygenation during intubation and for "tubeless" surgery - Highly turbulent supraglottic flow vortices and cardiogenic oscillations - Extends duration of time before desaturation with less accumulation of carbon dioxide than low flow apneic ventilation **[LASERS]** **L**ight **A**mplification by **S**timulated **E**mission of **R**adiation - [Monochromatic:] possess one wavelength - [Coherent:] oscillated in the same phase (all photons are moving in the same direction) - [Collimated:] exists as a narrow parallel beam A diagram of different types of laser sine waves AI-generated content may be incorrect. **Advantages:** - Surgical precision - Hemostasis - Less postoperative edema - Less postoperative pain **Types** - The [medium] used determines the wavelength - The [wavelength] determines function - Increased wavelength = increased water absorption = decreased tissue penetration  - Decreased wavelength = decreased water absorption = increased tissue penetration  - **Laser mediums:** - Gas: CO2 - Solid: YAG - Excimer: Argon - Semi-Conductor: not used clinically (laser printers, CD players) **Lasers used in ENT Procedures** - CO2 and Ho:YAG are used most often in ENT procedures - [CO2 lasers:] used for procedures in and around the larynx (shallow depth of burn and extreme precision) - [Ho:YAG lasers:] used for nasal surgery and tonsillectomies **Safety Precautions** - Suction evacuation of toxic fumes (Laser plume) - Respiratory masks for personnel (N-95) - Environmental concern- use smoke evacuators - Eye protection - Argon: orange - Nd:YAG: green - CO2: clear - OR windows should be covered and signs on doors - Prevention of airway fire - Minimize FiO2 - [Avoid nitrous oxide] - Laser resistant and well-sealed ETT - Limit laser intensity and duration - Saline soaked pledgets in airway - Fire extinguisher  **[SURGICAL FIRES]** **Fire Triad** - Ignition source - Electrosurgical units, lasers, fiberoptic light sources - Fuel source - Surgical drapes, alcohol skin prep, patient - Oxidizer - Oxygen, nitrous oxide, room air **Silverstein Fire Risk Assessment** - [Fire risk 1: Low risk] - Follow standard fire safety precautions - Let preop solutions dry for at least 3 minutes - Protect heat sources - Use a standard draping procedure - [Fire risk 2: Low risk with potential to convert to high risk] - Follow standard fire safety precautions, but be prepared to convert to high risk precautions if necessary - [Fire risk 3: High risk] - Follow standard fire safety precautions - Use high flow/low FiO2 - When electrocautery is used with an open oxygen delivery system, stop supplemental oxygen at least one minute before and while using cautery - Use wet sponges and have sterile water or saline available for fire suppression - Keep a syringe full of saline available for procedures in the oral cavity - Use the lowest electrocautery setting possible **Airway Fire** - [Signs:] - Darkening of ETT, LMA, or circuit with soot - Orange or red glow to ETT or LMA - Flames in or around ETT or LMA - ETT or LMA acts as a blowtorch - [Actions] - STOP VENTILATION AND REMOVE ETT - Turn off oxygen and disconnect circuit - Remove burning material from airway - Pour saline in airway - Ventilate with facemask and reintubate - Assess airway damage - Consider bronchial lavage and steroids  **[ENT PROCEDURES]** **Endoscopic Procedures** - Procedures: - Laryngoscopy - Microlaryngoscopy - Panendoscopy - Esophagoscopy - Bronchoscopy - Endoscopic sinus surgery  - **Common patient problems:** - Evaluation of hoarseness - Stridor - Hemoptysis - Foreign body aspiration - Vocal cord dysfunction - Tracheal stenosis - **Preop Eval:** Assess for potential airway problems - Size and location of tumor? CXR? CT scan? Baseline symptoms? - PPV possible? - Difficult intubation? - Antisialagogue or aspiration prophylaxis indicated? - **Perioperative management** - Use caution with routine premeds! - Optimize oxygenation while minimizing surgical interruption - Airway management plan - Small ETT or MLT? Intermittent apnea or jet ventilation? - Cardiovascular stability - Varying levels of stimulation - Baseline anesthetic with intermittent boluses or sympathetic antagonists prn - Muscle relaxation - Need profound relaxation (with rapid recovery) - **Prevention of complications** - Eye trauma/corneal abrasions - Epistaxis - Laryngospasm - Bronchospasm - LA toxicity - **Emergence and postop** - Adequate oropharyngeal suctioning prior to extubation - Humidified oxygen - Vigilance for laryngospasm, postextubation croup, stridor **Bilateral Myringotomy Tubes (BMT)** - **Common patient problems** - Chronic or recurrent otitis media - Frequent URI - **Preop eval:** Current URI? - **Intraoperative management** - Ultrashort procedure - Mask induction/maintenance with N2O, O2, Sevo - [N2O can be used for these procedures (short case and myringogotmy tube will allow egress of gas)] - Turn off inhalational agent when starting 2^nd^ ear; N2O at case completion - Airway equipment always prepared and immediately available - Often no IV unless indicated (i.e. another procedure being performed) - [Avoid preop sedatives (may outlast procedure) ] - Tylenol PR **Tonsillectomy and Adenoidectomy** - **Common patient problems** - Tonsillar and adenoidal atrophy - Potential airway obstruction - OSA - Cardiac and respiratory anomalies - CO2 retention - Cor pulmonale/Pulmonary HTN - Right heart failure - Speech and swallowing disorders - **Preop eval** - History of sleep disordered breathing (STBUR Questionnaire) - **S**noring - **T**rouble **B**reathing - **U**n**R**efreshed after sleep - Current URI? - **Anesthetic goals:** blunt airway reflexes, minimize bleeding, PONV prophylaxis, pain management, quick wakeup - **Perioperative Management** - **Kids** - Usually inhalation induction +/- parental presence - GA-ETT or LMA; balanced technique; [relaxation not routinely needed] - Cuffed ETT if age 8 or older (want air leak of at least 20 cm H2O) - **Adults** - IV induction/balanced technique; relaxation not routinely needed - **Both** - Shared airway - [Patient breathing spontaneously] - Rigid mechanical suspension of airway and mouth gag - Pain management - Quick emergence - Table turned 45-90 degrees away - Decreased FiO2 - **Prevention of complications** - Bleeding (6hr and at 6 days when the clot sloughs off) - Laryngospasm - Bronchospasm  - **Emergence and Postop** - Meticulous oropharyngeal suctioning - Control of bleeding prior to extubation - Decompress stomach (OGT) - To PACU in "tonsil" position (left lateral) - Vigilance for laryngospasm, post-extubation croup, stridor - **Post-tonsillectomy hemorrhage is a SURGICAL EMERGENCY** - Most common pediatric airway emergency surgery - [Risk factors:] age \>15, male, frequent infectious tonsillitis, "hot" electrocautery - Patients may swallow large volumes of blood (look for: hypovolemia, tachycardia, hypotension) - Do not suction stomach prior to induction (may dislodge clots) - Extreme care on DL - Slight head down position to protect glottis/trachea  - OGT [after] airway is secured - [Awake extubation] - Timing: - 6hrs / 6 days - Slow oozing is more common than profuse bleeding **Cleft Lip and Cleft Palate** - Often associated with other anomalies  - Surgical repair is performed in phased procedures - "Rule of 10" - Age \>10 weeks, Weight 10 kg, Hct \>10, WBC \