Airway Adjuncts (OPA / NPA)¶
Category: Procedures / Airway & Breathing Last updated: 2026-04-05 San Juan College EMT-B Program — New Mexico
Overview¶
Manual airway maneuvers — head-tilt/chin-lift and jaw thrust — open the airway but require continuous effort to maintain and will not hold position once you move on to other tasks. Airway adjuncts are mechanical devices that maintain airway patency passively, freeing the provider to assist ventilation or perform other interventions.
Two adjuncts are in EMT-B scope: the oropharyngeal airway (OPA) and the nasopharyngeal airway (NPA). Each has specific indications, contraindications, sizing methods, and insertion techniques. Using the wrong adjunct or the wrong technique causes more problems than it solves.
Airway Anatomy Review¶
Understanding why adjuncts work requires knowing what they are holding open.
The upper airway path: nasopharynx → oropharynx → hypopharynx → larynx → trachea
The single most common cause of airway obstruction in unconscious patients is the tongue. As consciousness decreases and muscle tone is lost, the tongue relaxes and falls posteriorly against the posterior pharyngeal wall. The airway is not structurally damaged — it is mechanically blocked by soft tissue.
Both the OPA and the NPA work by providing a structural channel through which air can pass around or past the tongue.
OPA — Oropharyngeal Airway¶
Purpose¶
The OPA displaces the tongue anteriorly and provides a rigid channel through the oropharynx. It is the preferred airway adjunct in deeply unconscious patients and is required before BVM ventilation whenever possible.
Indication¶
- Unconscious patient with absent or markedly diminished gag reflex
Contraindication¶
- Any intact gag reflex — absolutely contraindicated. Stimulating the gag reflex in a patient with a compromised airway will cause vomiting and aspiration. Death from aspiration in a patient with a marginal airway is a preventable complication. If the patient gags when you attempt to insert the OPA, remove it immediately and consider an NPA.
Sizing¶
Correct sizing is essential. An OPA that is too small will not displace the tongue; one that is too large can obstruct the larynx or cause soft tissue injury.
Measurement method: - Corner of the mouth to the earlobe (most common reference) - Center of the mouth to the angle of the jaw (also acceptable)
Hold the OPA adjacent to the patient's face to verify: the flange sits at the lips, the distal end reaches the angle of the jaw.
Available sizes: 0 (infant) through 6 (large adult). Common adult sizes: 4 (small adult), 5 (medium adult), 6 (large adult).
Insertion — Adult¶
Method 1 (standard adult rotation technique): 1. Confirm absent gag reflex before attempting insertion 2. Open mouth — head-tilt/chin-lift or jaw thrust 3. Insert the OPA upside down (curved end facing up toward the roof of the mouth) — the curve prevents pushing the tongue back during insertion 4. Advance until resistance is felt at the hard/soft palate junction 5. Rotate 180° so the curve now faces downward (anatomical position), following the contour of the tongue 6. Advance until the flange rests against the lips 7. Confirm placement: flange at lips, no gag, airway patent
Method 2 (tongue depressor technique): 1. Use a tongue depressor or laryngoscope blade to displace the tongue anteriorly 2. Insert OPA in anatomical position (curved end down) directly — no rotation needed 3. Advance until flange rests at lips
Insertion — Pediatric¶
Always use the tongue depressor technique in children. The rotation method is contraindicated in pediatric patients — the soft tissue of a child's hard palate can be damaged by the rotating tip of the OPA. Insert in anatomical position with tongue depressor to guide placement.
Confirmation¶
- Flange rests at the lips; OPA is not too deep or too shallow
- Patient does not gag
- Airway sounds are clear; no snoring
- Chest rise is visible with BVM ventilation
OPA and BVM¶
Insert the OPA before applying BVM when possible. The OPA maintains tongue displacement so the BVM can focus on delivering volume, not fighting tongue obstruction.
NPA — Nasopharyngeal Airway¶
Purpose¶
The NPA provides a soft, flexible channel through the nasopharynx. It is better tolerated than the OPA in patients who are not fully unconscious.
Indication¶
- Semi-conscious or conscious patients with an intact gag reflex who need airway support
- Clenched jaw (trismus) — OPA cannot be inserted
- Seizure patients (teeth may be clenched)
- When OPA is too stimulating for the patient's level of consciousness
Contraindication¶
- Suspected basilar skull fracture
- Signs: Battle's sign (ecchymosis posterior to ear), raccoon eyes (periorbital ecchymosis), CSF from nose or ears (clear fluid — may be glucose-positive on test strip)
- Basilar skull fracture may create a direct path through the cribriform plate into the cranial vault; NPA insertion risk intracranial placement
- If basilar skull fracture is suspected and airway intervention is needed: OPA (if tolerated) or BVM without adjunct, and ALS airway management
Sizing¶
- Length: Tip of nose to earlobe
- Diameter: Matches the diameter of the patient's little finger (external naris diameter)
Available in sizes 14–36 French. Larger number = larger diameter.
Insertion¶
- Lubricate the NPA with water-soluble lubricant (do not use petroleum-based lubricant)
- Select the right nostril (right naris is preferred — the septum curves rightward, making the right side anatomically straighter)
- Orient the bevel toward the nasal septum (medially)
- Insert with the tip aimed straight back toward the occiput — not upward (a common error that causes pain and trauma)
- Follow the floor of the nasal cavity; advance with gentle, steady pressure
- If resistance is felt: do not force. Gentle rotation or slight repositioning may help. If resistance persists, try the left nostril.
- Advance until the flange rests against the naris
- Confirm: airway sounds clear, patient breathing or ventilations passing through adjunct
NPA and Gag Reflex¶
The NPA can be used in patients who have a gag reflex — this is its main advantage over the OPA. Semi-conscious patients and patients with AMS who still have some protective airway reflexes tolerate the NPA better. You can still use an NPA in an unconscious patient.
Suctioning¶
When to Suction¶
Gurgling = suction immediately. Gurgling on inspiration or expiration is the sound of fluid (blood, vomit, secretions) in the airway. If you hear it, suction it. An obstructed airway cannot be oxygenated.
Indications: - Gurgling breath sounds - Visible secretions, vomit, or blood in the oropharynx - Patient unable to clear their own secretions
Catheter Types¶
Hard (rigid / Yankauer / tonsil-tip catheter: - Rigid plastic suction tip, large bore - Best for: oropharyngeal secretions, vomit, thick blood - Most common prehospital application - Do NOT insert past the base of the tongue (risks vagal stimulation and bradycardia)
Soft (flexible) catheter: - Thin, flexible tubing - Best for: through a nasopharyngeal airway, through an advanced airway (supraglottic device or ET tube), or when a rigid catheter cannot reach the area - Can be inserted deeper than a rigid catheter
Technique¶
- Turn on suction unit; verify suction is functioning (cover port — gauge should read pressure)
- Select catheter appropriate for the situation
- Measure depth for soft catheter: from the corner of the mouth to earlobe (do not insert deeper)
- Pre-oxygenate the patient before suctioning (hyperoxygenate critical patients)
- Insert without suction — suction applied on withdrawal only
- Apply suction and withdraw catheter using a circular or side-to-side motion
- Limit suction time:
- Adult: 15 seconds maximum per attempt
- Pediatric: 10 seconds maximum
- Infant: 5 seconds maximum
- Re-oxygenate between suction passes
- Reassess: confirm airway sounds improved; repeat if necessary
Why the time limit: Every second you are suctioning, you are also removing oxygen from the airway. In a patient who is already hypoxic, prolonged suctioning can worsen hypoxia and precipitate cardiac arrest.
Suction Pressure¶
- Recommended: 80–120 mmHg suction pressure
- Too low: does not effectively clear secretions
- Too high: can cause mucosal trauma and increase bleeding
NM Protocol Notes¶
- In New Mexico, EMT-B airway management includes OPA/NPA and BVM with suctioning
- Supraglottic airway devices (King LT, i-gel) may be in scope for NM EMT-B depending on the service — verify with your agency's medical director and current protocol
- Surgical cricothyrotomy is paramedic scope
- If airway management is failing at the EMT-B level: immediate ALS intercept, rapid transport, BVM with OPA/NPA as best available intervention
NREMT Relevance¶
Airway adjunct insertion is tested within the BVM ventilation skill station and the Patient Assessment skill stations. Examiners assess:
- Correct adjunct selection for the patient's mental status and gag reflex status
- Correct sizing technique (demonstrating measurement)
- Correct insertion technique (including rotation in adults, tongue depressor in peds)
- Suction technique if gurgling is present (indicating airway is not clear before BVM)
- Recognizing when an adjunct is contraindicated (NPA + basilar skull fracture; OPA + gag reflex)
Related¶
- bvm-ventilation — OPA/NPA are required adjuncts before BVM whenever possible
- primary-assessment — airway assessment drives the decision to use adjuncts
- respiratory-distress — adjuncts used in the airway management component of respiratory distress care
- head-injury-tbi — basilar skull fracture contraindication for NPA
- avpu — LOC level determines adjunct selection (OPA for deep unconscious, NPA for lighter LOC)