6.3 Laryngeal Mask Airway
Key Takeaways
- In NRP 9th Edition the laryngeal mask may be used as a primary advanced airway option for PPV—not only as a rescue device after failed endotracheal intubation.
- Indications include ineffective face-mask PPV and situations where intubation is not feasible or not successful; LMA also supports a secure airway when compressions are needed if ETT placement is delayed.
- Size selection follows weight/gestational bands and the device manufacturer’s guidance; classic size-1 teaching often maps to larger newborns (commonly around ≥34 weeks / ≥ about 2 kg), while smaller neonatal supraglottic sizes exist on some products.
- Confirm effective LMA ventilation with chest rise, rising heart rate, and exhaled CO2 detection when available—the same physiologic endpoints used for other advanced airways.
- LMA does not replace the need for MR SOPA face-mask corrections when the problem is a simple seal leak, and it is not a medication route equivalent to a correctly placed ETT for all drugs.
What a Laryngeal Mask Is—and Why NRP Elevated It
A laryngeal mask airway (LMA) (also called a supraglottic airway) is a soft mask attached to a tube that sits above the larynx, sealing around the laryngeal inlet so positive pressure can be delivered without needing a tube through the vocal cords. Unlike face-mask ventilation, the LMA does not depend on a perfect external facial seal. Unlike endotracheal intubation, it does not require laryngoscopic visualization of the glottis.
NRP 9th Edition clarifies that the laryngeal mask may be used as a primary advanced airway device, not merely as a rescue after multiple failed intubation attempts. Clinically this means teams can move to an LMA when face-mask PPV fails (the “A” in MR SOPA) even if intubation skill, equipment, or anatomy is not immediately favorable. Ventilation can be initiated with a face mask or a laryngeal mask when an advanced interface is needed.
This change matters most when:
- Mask ventilation remains ineffective after corrective steps
- Intubation is unsuccessful or not feasible (limited skilled operator, difficult anatomy, equipment delay)
- A more secure airway is needed for prolonged PPV or for coordination with chest compressions
- Time is critical and a rapid supraglottic seal will restore ventilation faster than repeated laryngoscopy
The LMA is not an excuse to skip basic MR SOPA when a simple mask reseat would work. It is the correct escalation when noninvasive face-mask technique cannot achieve effective lung inflation.
Indications in NRP Practice
High-yield indications aligned with NRP reasoning:
- Ineffective face-mask PPV despite MR SOPA corrections (no reliable chest rise / no heart-rate improvement).
- Intubation not successful after appropriate attempts, or not immediately feasible.
- Need for a more reliable airway during prolonged resuscitation, including when preparing for or performing compressions if an ETT is not yet in place.
- Certain difficult face-mask situations (unusual facial anatomy, poor seal despite correct technique) where a supraglottic device may succeed.
Relative limitations and cautions:
- Very small or extremely preterm infants may fall outside the validated size range of a given device—follow manufacturer weight bands and local policy; do not force an oversized classic LMA into an ELBW infant.
- Suspected congenital diaphragmatic hernia pathways still prioritize early endotracheal intubation and gastric decompression; prolonged bag-mask or poorly chosen interfaces that distend the gut are harmful—know special-situation priorities.
- An LMA does not guarantee protection from aspiration the way some believe a cuffed ETT does; it is a ventilation tool, not a perfect barrier.
- Not all medications are equivalently delivered via every airway type; intravenous/IO epinephrine remains preferred when vascular access is available.
Size Selection by Weight Bands (Teach Carefully)
Size selection is a frequent exam and skills-station topic. Always prioritize the device manufacturer’s sizing table packaged with the airway you actually stock, because product lines differ. Classic neonatal teaching still centers on:
| Approximate patient size | Common teaching (classic LMA) | Notes |
|---|---|---|
| Larger newborns, often ≥ about 2 kg and/or ≥ about 34 weeks | Size 1 laryngeal mask frequently taught as the standard neonatal size | Matches many NRP-oriented summaries and product labels for size 1 (often listed roughly 2–5 kg) |
| Smaller infants | May require manufacturer-specific smaller sizes (e.g., 0 / 0.5 or other neonatal supraglottic ranges on newer devices) | Do not invent a size; use the chart for that brand |
| Above typical neonatal range | Larger pediatric sizes | Rare in immediate newborn resuscitation |
How to teach this safely on exams and in practice
- Know the classic size-1 band used in many NRP discussions: roughly ≥34 weeks or ≥ ~2000 g for standard size-1 suitability in older teaching and many practice-bank items.
- Acknowledge 9th-edition primary-use language without claiming every micro-preemie has an LMA size that replaces intubation skill.
- If your unit stocks multi-size neonatal supraglottic airways, memorize those weight cutoffs for skills check-offs.
- When in doubt during a real resuscitation, choose the size that matches the estimated weight band on the package insert rather than guessing from adult trauma LMA habits.
Wrong size problems: too small leaks and fails to seal; too large will not seat properly and may obstruct or traumatize. Both present as “LMA in but still no chest rise.”
Insertion Technique Essentials
While brands vary, core insertion principles are consistent enough for NRP-level mastery:
- Prepare: Select size; check cuff integrity if the device is cuffed (inflate/deflate per instructions); have the PPV device ready with appropriate PIP/PEEP settings; suction available.
- Position: Neutral/sniffing airway position; stand at the head of the bed.
- Insert: Deflated cuff (if applicable) following the hard palate, advancing until resistance indicates seating around the larynx; avoid folding the tip.
- Inflate cuff to the recommended volume/pressure if the model uses a cuff—do not overinflate.
- Connect the T-piece or bag and begin ventilation.
- Confirm effectiveness immediately (below).
- Secure the device and continue monitoring; plan next steps (wean, intubate for longer-term airway, or transfer).
Work as a team: one person inserts while another prepares confirmation tools and continues cardiac monitoring. Call out the time and the result: “LMA placed, chest rising, heart rate up to 140.”
Confirmation: Chest Rise, Heart Rate, CO₂
Placement is not confirmed by “it looked easy” alone. Use the same physiologic logic as ETT confirmation:
| Confirmation method | What success looks like | Pitfalls |
|---|---|---|
| Chest rise | Bilateral, gentle rise with each breath | Asymmetric rise may mean poor seal, mainstem-like malposition effects, or pneumothorax—reassess |
| Heart rate | Rising HR is the best indicator of effective ventilation | Persistently low HR means ineffective ventilation or need for further algorithm steps |
| Exhaled CO₂ detector (if available) | Color change / waveform consistent with CO₂ return during effective pulmonary ventilation | No CO₂ with no HR improvement suggests ineffective ventilation or absent pulmonary blood flow; do not assume “device magic” |
| Breath sounds | Bilateral air entry | Can be misleading in noisy rooms; never ignore absent chest rise |
| Improving SpO₂ | Gradual rise toward targets | Delayed by poor perfusion; still useful once signal is reliable |
If confirmation fails: remove or reseat the LMA, return to face-mask PPV with MR SOPA if needed, and consider endotracheal intubation by the most experienced available operator. Do not leave a non-functioning advanced airway in place while the heart rate collapses.
LMA Versus ETT Versus Face Mask
| Feature | Face mask | LMA (supraglottic) | Endotracheal tube |
|---|---|---|---|
| Skill demand | Universal NRP skill | Moderate; faster than intubation for many | Highest; requires laryngoscopy |
| Seal reliability | Variable | Often better than face mask when seated | Highest when correctly placed |
| 9th-ed role | First interface for most PPV | Primary advanced option as well as rescue | Gold-standard definitive airway |
| Best for | Initial PPV, short support | Failed mask PPV; intubation not feasible | Prolonged ventilation, certain anomalies, surfactant pathways, some med routes |
| Compressions phase | Less ideal alone | Acceptable advanced airway if ETT not yet placed | Preferred when achievable |
Integrating LMA with MR SOPA and compressions
- A = Alternative airway includes ETT or LMA.
- When HR remains <60 after effective ventilation, start compressions and increase oxygen toward 100% per algorithm; securing an advanced airway (ETT preferred when possible, LMA if intubation fails or is not feasible) improves coordination and CO₂ monitoring.
- Do not delay ventilation for endless laryngoscopy if an LMA can restore chest rise now.
Scenario Drill
A 36-week, 2.6 kg newborn receives face-mask PPV for apnea. Heart rate is 50 with no chest rise. The team reseats the mask, repositions, suctions mouth then nose, opens the mouth, and increases PIP—still no rise. The most experienced intubator is not yet in the room.
Correct thinking: Proceed to an alternative airway. A size-appropriate laryngeal mask is an acceptable primary advanced airway now. Insert, ventilate, confirm chest rise and heart-rate response (and CO₂ if available). If HR remains <60 after effective ventilation for ≥30 seconds, begin compressions with coordinated ventilation. When an intubator arrives, decide whether to convert to ETT based on ongoing needs.
Exam traps
- Stating that LMA is only allowed after three failed intubations (outdated relative to 9th-edition primary-option language).
- Choosing LMA for a vigorous, crying newborn who needs only routine care.
- Using adult size 3–4 devices on newborns.
- Confirming placement by “I felt resistance” alone without chest rise/HR/CO₂ logic.
- Believing free-flow oxygen through an LMA replaces the need for PPV in apnea.
- Forgetting that face-mask MR SOPA still comes first when the problem is a correctable seal leak.
Master the indications, the size-by-weight caution, and the confirmation triad (chest rise, heart rate, CO₂). That is the NRP 9th-edition laryngeal-mask skill set.
According to NRP 9th Edition emphasis, which statement about the laryngeal mask is most accurate?
Which combination best confirms effective ventilation after laryngeal mask placement?
A team is selecting a classic size-1 laryngeal mask for newborn resuscitation. Which sizing concept is most consistent with common NRP-oriented teaching?