Airway Management in Anesthesia

Flashcards covering airway anatomy, assessment scores, equipment specifics, intubation techniques, and emergency procedures as presented in the lecture notes.

Upper Airway

The anatomical region that ends at the vocal cords; it includes the epiglottis which protects the lower airway during swallowing.

Mallampati score

A visual physical exam of the tongue and uvula (I–IV) used to predict intubation difficulty; scores II–IV correlate with harder intubation.

Thyromental distance

A physical exam measurement used in preoperative assessment that should be greater than $6\,cm$ for a normal airway.

Retrognathia

A high-risk physical feature characterized by a small jaw, which may predict a difficult airway.

Preoxygenation

The administration of $100\%$ $O_2$ for $3–5$ minutes (or 8 vital-capacity breaths) to maximize the patient's apneic reserve.

Sniffing position

A positioning technique involving neck flexion and head extension to align the ear to the sternal notch, optimizing the view for intubation.

C-E grip

A two-hand mask seal technique where the thumb and index finger form a "C" on the mask while the other fingers provide jaw thrust (forming an "E").

Macintosh blade

A curved laryngoscope blade (sizes #3–4) inserted into the vallecula to lift the epiglottis indirectly for vocal cord visualization.

Miller blade

A straight laryngoscope blade (sizes #1–2) used to lift the epiglottis directly; preferred in pediatrics or patients with ankylosis.

Bougie (Gum elastic bougie)

An airway adjunct used to facilitate difficult laryngoscopy when the vocal cords are only partially visible.

Capnography

The mandatory monitoring of end-tidal $CO_2$ used to confirm endotracheal tube placement and ventilation.

Cormack-Lehane Grade

A classification system used during laryngoscopy to describe the view of the vocal cords, where Grade I is a full view and Grade IV is no view of the glottis.

Video Laryngoscopy

A technique using a camera at the blade tip to project the vocal cords on a screen, often improving the view in Cormack III/IV scenarios.

SGA (Supraglottic Airway)

A class of devices like the LMA or i-gel used for rescue ventilation or elective short cases that do not protect against aspiration.

ProSeal LMA

A second-generation laryngeal mask airway that features a gastric channel for improved safety.

i-gel

A second-generation supraglottic airway device that features a non-inflatable cuff.

Adult ETT Size

Typically $\sim 7.0\,mm$ internal diameter (ID) for females and $\sim 8.0\,mm$ ID for males.

Pediatric ETT formula

A calculation for the internal diameter of uncuffed pediatric tubes: $(\text{age}/4 + 4)\,mm$.

Hockey-stick bend

The shaping of an ETT stylet where it is kept straight to the cuff and then bent at a $\sim 35^{\circ}$ angle.

Rapid Sequence Intubation (RSI)

An intubation technique used for high aspiration risk (e.g., full stomach) involving preoxygenation, induction, and rapid paralysis without bag-mask ventilation.

Succinylcholine

A short-acting paralytic agent with an onset of $30-60$ seconds used during induction.

Emergency Cricothyrotomy

An emergency airway procedure indicated in "can't intubate, can't ventilate" scenarios, involving an incision in the cricothyroid membrane.

Scalpel-Bougie Method

The fastest and most reliable technique for emergency cricothyrotomy using a #10 scalpel, a bougie, and a $6.0–6.5\,mm$ ETT.

Apneic oxygenation

The application of high-flow $O_2$ ($15\,L$) via nasal cannula during prolonged intubation attempts to maintain saturation.

Sellick maneuver

The application of cricoid pressure to prevent aspiration during induction, though its use is considered controversial.

Maximum Cuff Pressure

Endotracheal tube cuff pressure should be kept below $30\,cmH_2O$ to avoid trauma.