OPA and NPA Insertion: How to Measure, Insert, and Use Them Properly

When airway management is critical, knowing how to measure OPA and NPA and how to insert them effectively can make all the difference. Both oropharyngeal airways (OPA) and nasopharyngeal airways (NPA) are essential tools for medical professionals and students to master before progressing to more advanced techniques like endotracheal intubation or cricothyrotomy. Let’s break down what every clinician needs to know.

What Does OPA and NPA Stand For?

• OPA: Oropharyngeal Airway
• NPA: Nasopharyngeal Airway

Both devices help maintain an open airway but differ in placement. OPA is inserted through the mouth, while NPA is inserted through the nasal passage.

Difference Between OPA and NPA

The main difference between OPA and NPA lies in insertion site and patient tolerance:

• OPA is used for unconscious patients without a gag reflex, as it can trigger vomiting if used in alert individuals.
• NPA is better tolerated in semi-conscious or conscious patients as it bypasses the gag reflex via the nasal route.

How to Measure OPA and NPA Correctly

Measuring OPA and NPA is crucial to ensure effective ventilation and avoid complications.

• How to size OPA: Measure from the corner of the patient’s mouth to the angle of the mandible.
• How to measure NPA: Measure from the tip of the nose to the earlobe or the angle of the mandible.

Proper sizing ensures the airway device is long enough to keep the airway open but not so long that it causes trauma.

How to Insert OPA and NPA (Step-by-Step)

OPA Insertion:

1. Position the patient in a supine position.
2. Open the airway using a head-tilt, chin-lift maneuver.
3. Insert the OPA upside down until it reaches the soft palate, then rotate 180 degrees to follow the natural curve.
4. Ensure the flange rests against the lips.

NPA Insertion:

1. Apply water-based lubricant to the NPA.
2. Gently insert the airway into the nostril (preferably the right nostril) at a perpendicular angle.
3. Advance along the nasal floor until the flange rests against the nostril.

These steps are critical when learning how to insert OPA and NPA properly.

OPA and NPA Indications and Contraindications

When do we use an NPA and OPA instead of intubation?

• Indications:
  • Airway obstruction due to the tongue
  • Pre-oxygenation prior to intubation
  • Basic airway management during seizures or trauma
• Contraindications:
  • OPA: Conscious or semi-conscious patients with a gag reflex
  • NPA: Suspected basilar skull fracture, severe nasal trauma

In emergency or pre-hospital care, inserting OPA and NPA is often preferred over invasive methods when endotracheal intubation or cricothyrotomy is unavailable or unnecessary.

Adult vs Pediatric OPA/NPA Insertion: What's the Difference?

The difference between OPA and NPA use in adults and children mainly involves:

• Sizing: Pediatric patients require smaller airway adjuncts, carefully measured to avoid airway trauma.
• Technique: For infants, OPA is inserted with a tongue depressor to avoid soft tissue injury (no rotation technique).
• Precautions: Children are more sensitive to airway manipulation; care must be taken to monitor for bradycardia due to vagal stimulation.

Precautions for NPA and OPA

• Always confirm correct sizing before insertion.
• Use lubrication for NPA to reduce mucosal damage.
• Avoid forceful insertion to prevent trauma or bleeding.
• Monitor patient continuously for signs of airway compromise or intolerance.

Recommended Model for OPA and NPA Training

For hands-on practice, simulation models are indispensable. We recommend the MedEduQuest Adult Airway Management Trainer Kit. This versatile airway trainer is designed to help students and clinicians master both OPA and NPA insertion, correct sizing techniques, and other airway maneuvers in a safe, realistic environment.