Category: Fundamentals In patients receiving high concentrations of supplemental O2, nitrogen in the alveoli is replaced by O2. If O2 is absorbed into the blood faster than it is replaced, the volume of the alveoli will decrease and absorptive atelectasis can occur.
Category: Fundamentals Preoxygenation prior to endotracheal intubation is one of the most important aspects of emergency airway management. The goal of preoxygenation is to replace all nitrogen in the lungs with oxygen.
Category: Fundamentals The primary advantage of the Venturi mask system is that FiO2 can be precisely controlled between 21% and 35% for patients who may not tolerate a higher or imprecise FiO2.
Category: Fundamentals The Venturi mask is a titratable oxygen delivery device that is widely available, though it is used more frequently in the inpatient and intensive care unit setting than in the emergency department.
Category: Fundamentals Non-rebreathing masks have a series of one-way valves. One valve lies between the mask and the reservoir, preventing exhaled gas from entering the reservoir. Two valves on the side of the mask permit exhalation while preventing outside air entry.
Category: Fundamentals Partial non-rebreather masks have a reservoir to increase the amount of O2 available, requiring less outside air to be entrained. Non-rebreathing masks are similar to partial rebreathing masks but have a series of one-way valves.
Category: Fundamentals Nasal cannulas are generally set to 2 to 4 L/min, which provides approximately 30% to 35% FiO2. Although it may seem intuitive, patients using a nasal cannula should be reminded that they should not smoke while oxygen is being delivered.
Category: Fundamentals The FiO2 delivered by nasal cannulas is determined by many factors, including the respiratory rate, tidal volume, pharyngeal geometry and O2 flow. Most importantly, at a constant O2 flow rate, FiO2 varies inversely with the respiratory rate.
Category: Fundamentals The prongs of a nasal cannula deliver a constant flow of O2 that accumulates in the nasopharynx and provides a reservoir of oxygen-enriched air for inspiration. The FiO2 delivered by nasal cannulas is determined by many factors.
Category: Fundamentals Although 100% oxygen may have been used during initial resuscitation, providers should titrate inspired oxygen to the lowest level required to achieve an arterial oxygen saturation of ≥94%, to avoid potential oxygen toxicity.
Category: Fundamentals The goals of cardiopulmonary resuscitation are to restore energy to the heart so it can resume normal function and ensure adequate energy supply to the brain during resuscitation. Oxygen is vital to these goals.
