What Is an Oropharyngeal Airway (OPA)? A Guide to Size Selection and Safe Use in Healthcare Facilities
Maintaining a patent airway is one of the first priorities when caring for critically ill, unconscious, or unresponsive patients. In these situations, reduced muscle tone in the jaw and tongue may cause the tongue to fall backward and obstruct airflow. If this obstruction is not relieved promptly, oxygen delivery may be compromised, increasing the risk of hypoxia, brain injury, and cardiac arrest.
One simple and practical device used to help maintain airway patency is the oropharyngeal airway. This device is also known as an OPA, oral airway, or Guedel airway. It is commonly used in emergency departments, operating rooms, intensive care units, ambulances, and resuscitation areas.
Despite its relatively simple design, selecting the wrong size or using an OPA in an unsuitable patient may worsen airway obstruction. Therefore, healthcare facilities should consider not only product quality but also size availability, the patient’s clinical condition, and the manufacturer’s instructions for use when purchasing and using these devices.
What Is an Oropharyngeal Airway?
An oropharyngeal airway is a curved medical device inserted through the mouth into the pharynx. It helps maintain an open airway by preventing the tongue from falling backward and obstructing airflow.
The device is typically manufactured from medical-grade polymeric materials and has a curvature designed to follow the anatomy of the mouth and pharynx. Its outer end has a flange that remains outside the mouth and helps prevent the device from being inserted too deeply.
An OPA is a temporary airway adjunct. It should not be confused with an endotracheal tube, laryngeal mask airway, or other advanced airway devices.
Main Components of an Oropharyngeal Airway
OPA design may vary by manufacturer, but most standard devices consist of the following components:
Flange
The flange remains outside the mouth and helps prevent the airway from moving too far into the pharynx. The device size or length is usually marked on or near this section.
Reinforced Bite Section or Bite Block
This section lies between the teeth and should be strong enough to resist deformation under normal biting pressure. However, an OPA should not be used solely as a bite block in every patient or clinical situation.
Curved Body
The curvature of the body is designed to follow the shape of the tongue and pharynx. When correctly positioned, it holds the tongue in a position that helps prevent airway obstruction.
Pharyngeal or Distal Tip
The distal end lies within the pharynx. Its length must be appropriate for the patient’s anatomy, as an airway that is too short or too long may not function properly and can cause complications.
Air Channel
The central or lateral channel allows air to pass through the device. Depending on the product design and clinical situation, some OPAs may also permit the passage of an appropriately sized suction catheter.
How Does an OPA Help Maintain Airway Patency?
In a conscious person, muscle activity in the jaw and tongue normally helps prevent upper airway obstruction. When the level of consciousness is significantly reduced, muscle tone decreases and the base of the tongue may move toward the posterior pharyngeal wall.
An OPA lies over the tongue and helps prevent it from falling backward and obstructing airflow. Correct placement may also make bag-mask ventilation easier and more effective.
According to the American Heart Association, the use of an oropharyngeal or nasopharyngeal airway may be reasonable in an unconscious or unresponsive patient without a cough or gag reflex to facilitate effective ventilation.
When Is an Oropharyngeal Airway Used?
Common indications for an OPA include:
- Helping maintain airway patency in an unconscious patient without a gag reflex
- Facilitating ventilation with a bag-valve mask
- Supporting airway management during cardiopulmonary resuscitation by trained personnel
- Providing temporary airway support in the operating room and during anesthesia
- Assisting in the care of selected patients with a significantly reduced level of consciousness
- Providing short-term airway support until a more advanced airway device is available
- Facilitating access for suctioning secretions when permitted by the product design
An OPA should only be used after the patient has been appropriately assessed and by a trained healthcare professional. Unconsciousness alone is not sufficient; the presence or absence of cough and gag reflexes must also be evaluated.
When Should an OPA Not Be Used?
The most important contraindication to using an OPA is the presence of an active gag or cough reflex. Inserting an OPA in a conscious or semiconscious patient may cause gagging, vomiting, aspiration, or laryngospasm.
An OPA should generally not be used in the following situations:
- The patient is conscious, responsive, or resisting
- An active gag or cough reflex is present
- There is severe trauma to the mouth, tongue, or pharynx
- Mouth opening is severely restricted or trismus is present
- A foreign body or fixed obstruction is present in the airway
- The patient actively resists insertion
- Insertion could worsen bleeding or tissue injury
If a patient begins coughing, gagging, vomiting, or resisting after OPA placement, tolerance of the device must be assessed immediately. Whether the device should remain in place or be removed must be determined according to the patient’s condition and the healthcare facility’s airway management protocol.
Does an OPA Prevent Secretions from Entering the Lungs?
No. An oropharyngeal airway is not a definitive airway and does not protect the lungs from blood, saliva, gastric contents, or other secretions.
It also cannot remove foreign bodies or fluids from the mouth and pharynx. If secretions, blood, or vomit are present, appropriate airway clearance and suctioning remain necessary.
An OPA must not be considered a substitute for endotracheal intubation, suctioning, oxygen therapy, or any other intervention required by the patient.
What Is the Difference Between an OPA and an Endotracheal Tube?
An OPA is positioned only within the mouth and pharynx. It does not pass through the larynx or enter the trachea. Its main purpose is to help prevent the tongue from obstructing the airway.
An endotracheal tube passes through the vocal cords and into the trachea. It is used for mechanical ventilation, controlled oxygen delivery, and advanced airway management.
Therefore, an OPA is a temporary airway adjunct, whereas an endotracheal tube can provide an advanced and relatively protected airway when correctly placed in an appropriate patient.
What Is the Difference Between an Oropharyngeal and a Nasopharyngeal Airway?
An oropharyngeal airway, or OPA, is inserted through the mouth and is generally suitable for an unconscious patient without a gag reflex.
A nasopharyngeal airway, or NPA, is inserted through the nose and may be better tolerated by some patients who retain a degree of consciousness or an intact gag reflex. However, NPAs have their own limitations and contraindications. For example, they should not be used without specialist assessment in certain cases of severe facial trauma or suspected basilar skull fracture.
The choice between an OPA and an NPA should be based on the patient’s condition, the nature of any injury, and the applicable airway management protocol.
Why Is Correct OPA Size Selection Important?
Selecting the correct size is one of the most important factors affecting OPA safety and effectiveness. The appropriate size cannot be determined solely by the patient’s age or sex or by the device color because facial and mandibular anatomy varies between individuals.
OPA Too Short
If the OPA is shorter than required, it may fail to hold the tongue in the correct position. In some cases, an airway that is too short may push the tongue backward and worsen airway obstruction.
OPA Too Long
An excessively long OPA may be inserted too deeply and apply pressure to the epiglottis, larynx, or surrounding soft tissues. This may cause tissue injury, coughing, gagging, laryngospasm, or airway obstruction.
How to Select the Correct OPA Size
One commonly used method of estimating the appropriate size is to hold the OPA alongside the patient’s face. In this method:
- The flange is positioned beside the lips or at the corner of the mouth.
- The distal tip should approximately reach the angle of the mandible.
Some clinical references use the distance from the maxillary incisors to the angle of the mandible as an alternative external measurement. Clinical studies suggest that external facial measurements can help with initial size selection, but the final assessment should be based on the individual patient’s anatomy and clinical condition.
Color coding may make size selection faster. However, colors and numbering systems may vary among manufacturers. Healthcare personnel should therefore verify the nominal length and size marking in addition to the device color.
OPA Sizing for Pediatric and Adult Patients
OPAs are generally available in neonatal, pediatric, and adult sizes. Common product ranges may include lengths of approximately 40 to 110 millimeters, although the exact size range and numbering system must be confirmed using the manufacturer’s documentation.
Using a fixed age-based table without an anatomical measurement is not an appropriate method of selecting an OPA. Healthcare facilities should maintain a range of sizes suitable for the patient populations they serve.
For example, some resuscitation equipment lists recommend sizes 2, 3, and 4 for adult patients. However, this should not be treated as a universal rule for every patient. Pediatric, neonatal, and emergency departments require a broader range of sizes appropriate to their patient population.
Additional caution is required when considering an OPA for premature infants. Resuscitation Council UK guidance warns that an OPA may contribute to airway obstruction in some infants born before 34 weeks of gestation.
General Principles of OPA Insertion
OPA insertion is a clinical procedure and should only be performed by trained personnel in accordance with the manufacturer’s instructions and the healthcare facility’s airway management protocol.
Before insertion, the mouth and airway should be assessed and, when necessary, cleared of visible secretions, blood, or foreign material. The correct size should then be selected, and the device should be inserted without excessive force.
In adults, either a controlled rotation technique or direct insertion with the assistance of a tongue depressor may be used. In children, direct insertion while controlling the tongue is generally preferred because rotating the device may injure the hard or soft palate or push the tongue backward.
After placement, the following should be assessed:
- Airway patency
- Adequate chest movement
- Quality of bag-mask ventilation
- Abnormal airway sounds
- Oxygen saturation and respiratory status
- Coughing, gagging, or patient resistance
- Correct position of the flange outside the mouth
The presence of an OPA in the mouth does not guarantee a patent airway. The patient must be monitored continuously.
Potential Complications of Incorrect OPA Use
Inappropriate use, incorrect size selection, or placement in a patient with an intact gag reflex may cause the following complications:
- Gagging, nausea, and vomiting
- Aspiration of gastric contents
- Laryngospasm
- Injury to the tongue, palate, lips, or pharynx
- Mucosal bleeding
- Dental injury
- Excessive pressure on oral tissues
- Worsening airway obstruction
- Device displacement or expulsion
- Delay in establishing a required advanced airway
To reduce these risks, healthcare personnel must be trained in OPA size selection, insertion, and patient monitoring.
A Purchasing Guide for Healthcare Facilities
Procurement managers and medical equipment personnel should not select an OPA based solely on price or color coding. The design and manufacturing quality of this device are directly related to patient airway safety.
Compliance With Applicable Standards
ISO 5364:2026 specifies requirements for oropharyngeal airways. ISO 18190:2025 sets out general requirements for airway devices and related equipment, including requirements concerning design, materials, marking, packaging, and information supplied by the manufacturer.
Before purchasing, the product’s technical documentation and compliance with the standards and regulatory requirements of the destination market should be reviewed.
Complete Range of Sizes
The available size range should correspond to the patient population served by the healthcare facility. General hospitals, emergency departments, and facilities with pediatric units require a wider range of sizes than adult-only centers.
Clearly Marked Size and Length
The airway size or length should be clearly and legibly marked on the device or flange. Color coding can accelerate identification, but it should not be the only method used to determine device size.
Surface and Edge Quality
The OPA surface should be smooth and free from sharp edges, burrs, or other features that could injure the patient. The distal tip and flange should also be appropriately designed to reduce the risk of mucosal trauma.
Strength of the Bite Section
The section positioned between the teeth should have sufficient strength to resist deformation or breakage under normal clinical pressure.
Appropriate Air-Channel Design
The internal channel should be open and uniform. Deformation, obstruction, or an abnormal reduction in cross-sectional area may increase resistance to airflow.
Packaging Quality
Packaging should protect the product against contamination, physical damage, and deformation. For sterile products, the integrity of the sterile barrier, sterilization method, and expiration date should be verified.
Traceability
A lot or batch number, manufacturing date, expiration date where applicable, manufacturer’s name, product specifications, and valid registration information help ensure effective product control and traceability.
Single-Use or Reusable Designation
If an OPA is labeled for single use, it must not be reused or reprocessed. Reusing a single-use device may compromise its performance, strength, cleanliness, and safety.
Sample Evaluation Before Bulk Purchasing
Before placing a bulk order, a sample should ideally be evaluated by the medical equipment department, an anesthesiologist, the emergency team, or the resuscitation officer. Important evaluation criteria include the clarity of size markings, surface quality, structural strength, ease of opening the packaging, and compatibility with the facility’s clinical workflow.
Oropharyngeal Airway Purchasing Checklist
Before finalizing a purchase, review the following:
- A size range appropriate for the patient population
- Clear size numbering and length markings
- Recognizable and documented color coding
- Smooth surfaces without potentially harmful edges
- Adequate strength of the bite section
- An open, undeformed air channel
- Intact and durable packaging
- Clearly stated sterile or non-sterile status
- Clearly stated single-use or reusable designation
- Clear instructions for use, including a Persian version where required for the Iranian market
- Lot or batch identification and product traceability
- Manufacturing and expiration dates where applicable
- Valid technical documentation and regulatory approvals
- Appropriate storage and transportation requirements
- Reliable availability of frequently used sizes
Conclusion
An oropharyngeal airway is a simple but important device for temporary airway management. In an unconscious patient without a gag reflex, it can help prevent the tongue from obstructing the airway and may facilitate bag-mask ventilation.
The safety and effectiveness of an OPA depend on three main factors: appropriate patient selection, correct size selection, and proper placement by a trained professional. An incorrectly sized OPA or its use in a patient with an intact gag reflex may cause tissue injury, vomiting, aspiration, or worsening airway obstruction instead of improving the patient’s condition.
When purchasing OPAs, healthcare facilities should consider manufacturing standards, size range, surface quality, structural strength, marking, packaging, and product traceability. For information about available sizes, technical specifications, and supply conditions, please contact the specialists at Makhazen Tebi Abadis.
This article is intended to provide a scientific introduction to oropharyngeal airways. It is not a substitute for hands-on clinical training, the manufacturer’s instructions for use, or the healthcare facility’s airway management protocol.
References
- American Heart Association – Adult Basic Life Support Guidelines
- ISO 5364:2026 – Oropharyngeal Airways
- ISO 18190:2025 – General Requirements for Airway Devices
- Queensland Ambulance Service – Oropharyngeal Airway Device
- Oropharyngeal Airway – StatPearls, NCBI Bookshelf
- Resuscitation Council UK – 2025 Paediatric Life Support Guidelines
- Determination of Appropriate Sizes of Oropharyngeal Airways – PubMed
- Resuscitation Council UK – Acute Care Equipment and Drug Lists
