Oxygen is useful in patients in cardiac arrest, respiratory distress, or during stroke. The goal is to maintain oxygen saturation at 94% or greater, and supplemental oxygen can be titrated between 21% and 100% to achieve this goal.

There are various devices used to deliver oxygen:

• Nasal cannula
• Face mask
• Venturi mask
• Face mask and oxygen reservoir

To use an oxygen device, the rescuer must ensure that it is working properly, including the oxygen tubing, valves, pressure gauge, and flow meters. Staff should make sure to familiarize themselves with the equipment before the emergency.

When providing CPR, ventilation refers to the process of ensuring the proper amount of oxygen and utilizes physiological factors such as respiratory rates, tidal volumes, and oxygen concentrations. However, the optimal levels of these parameters are currently not known, although the levels of oxygen saturation are generally close to normal immediately following cardiac arrest. Many providers will give 100% oxygen concentration during the resuscitation event to improve oxygen delivery. It is unlikely that high oxygen concentration in the short term will lead to oxygen toxicity. The 2015 AHA guidelines recommend delivery of up to 100% inspired oxygen concentration during CPR.⁹

Considering Airway Obstruction

Significant obstruction in the upper airway will lead to obstructive noises such as stridor. Additionally, the conscious patient may be observed to use accessory respiratory muscles. If the patient is not breathing, signs may be more subtle, such as bradycardia (from unrecognized hypoxemia).

If the patient is unconscious, obstruction is mostly caused by a relaxed airway, which is managed by simple techniques to open the airway, such as the head tilt-chin lift or the jaw thrust maneuver (in the patient who has a suspected cervical injury). Additionally, nasopharyngeal (NPA) and oropharyngeal airways (OPA) can be placed in patients who have no gag reflex.

Related Video: Rescue Breathing for Adults

Airway Anatomy

Tongue and epiglottis obstruction are relieved by head tilt-chin lift maneuver and jaw thrust maneuver.

Tongue and epiglottis obstruction are relieved by head tilt-chin lift maneuver and jaw thrust maneuver.