Final answer:
NPA is used for maintaining an open airway when an OPA cannot be inserted, while an OPA is easier to insert but contraindicated in conscious patients. NPAs are contraindicated in patients with severe head injuries or basal skull fractures. Both airways are crucial for patient airway management in emergency or clinical settings.
Step-by-step explanation:
An NPA, or Nasopharyngeal Airway, is a tube designed to be inserted into the nasal passageway to secure an open airway. It is typically used when a patient may have an obstructed oral airway when insertion of an OPA is not possible due to clenching of teeth or when injuries to the mouth preclude its use. NPAs are generally contraindicated in patients with severe head injuries, especially basal skull fractures, due to the risk of the tube entering the cranial vault through the fracture site.
An OPA, or Oropharyngeal Airway, is designed to be inserted into the mouth to keep the airway open. OPAs are easier to insert and are useful in patients who are unconscious as they have no gag reflex, which is a contraindication for OPA use. OPAs are also contraindicated in cases where the patient is conscious or semi-conscious, as it could induce vomiting or aspiration.