Oxygen Therapy and Ventilatory Support - NREMT: AEMT Level

$6$ to $10$ L/min. This range delivers 40-60% FiO2, suitable for moderate hypoxemia, but requires minimum flow to flush exhaled CO2.

$10$ to $15$ L/min (keep reservoir inflated). High flow maintains reservoir inflation to deliver near 100% FiO2 by preventing room air entrainment during inhalation.

$1$ to $6$ L/min. This flow provides low to moderate FiO2 (24-44%) comfortably for patients with mild hypoxemia who can breathe spontaneously.

SpO$_2$ about $88%$ to $92%$. Lower targets prevent suppression of hypoxic respiratory drive in chronic hypercapnic patients, balancing oxygenation with CO2 retention risks.

SpO$_2$ about $94%$ to $99%$. This range ensures adequate oxygenation without risking oxygen toxicity in stable adult patients not at risk for hypercapnia.

Low pulse oximetry (SpO$_2$) with clinical correlation. Pulse oximetry measures oxygen saturation noninvasively, but must be interpreted alongside clinical signs like cyanosis or altered mental status for accuracy.

Correct hypoxemia by improving oxygenation. Oxygen therapy aims to increase alveolar oxygen levels to enhance tissue oxygenation in patients experiencing low blood oxygen saturation.

Approximately $21%$ oxygen. Room air consists primarily of nitrogen (78%) and oxygen (21%), with trace gases making up the remainder at standard atmospheric pressure.

Assist ventilations with BVM and oxygen. Tachypnea with shallow breaths and fatigue signals impending respiratory failure, necessitating assisted ventilation to improve gas exchange.

Reposition airway and reseal mask; consider obstruction. Inadequate chest rise indicates failed ventilation, often due to poor seal, airway malposition, or blockage requiring prompt troubleshooting.

Poor perfusion causing unreliable pulse oximetry. Peripheral vasoconstriction from shock or cold reduces pulsatile flow, leading to inaccurate SpO2 readings despite potentially normal oxygenation.

Acute cardiogenic pulmonary edema with distress. CPAP reduces preload and afterload while improving oxygenation, alleviating respiratory distress in pulmonary edema from heart failure.

Apnea or respiratory arrest. CPAP requires spontaneous breathing to be effective; apnea necessitates ventilatory support like BVM to prevent hypoxia and hypercapnia.

Waveform capnography (ETCO$_2$ trending). It provides real-time graphical ETCO2 monitoring, confirming tube placement and assessing ventilation adequacy more reliably than colorimetry.

Nasopharyngeal airway (NPA). NPA is better tolerated in semi-conscious patients as it bypasses the oral cavity and does not stimulate the gag reflex as strongly.

Oropharyngeal airway (OPA). OPA insertion can trigger gagging or vomiting in responsive patients, risking aspiration, so it's reserved for unconscious individuals without reflexes.

Deliver each breath over about $1$ second. Slow delivery minimizes peak inspiratory pressure, reducing risks of gastric distension and lung injury from excessive volume or pressure.

$1$ breath every $6$ seconds (about $10$/min). During CPR with an advanced airway, asynchronous ventilations at this rate support circulation without interrupting compressions.

About $1$ breath every $3$ to $5$ seconds. Children have higher metabolic rates and oxygen demand, requiring faster ventilation (12-20 breaths/min) to match physiological needs.

About $1$ breath every $5$ to $6$ seconds. This rate (10-12 breaths/min) maintains adequate oxygenation and CO2 elimination without causing hyperventilation in patients with a pulse.

BVM ventilations with oxygen. Apnea requires immediate positive pressure ventilation to oxygenate and ventilate until spontaneous breathing resumes or advanced care is available.

Reservoir bag inflated and one-way valves functioning. These ensure the device prevents exhaled air re-entry and maintains high FiO2 by storing oxygen for inhalation.

At least $6$ L/min. Lower flows allow CO2 accumulation in the mask's dead space, increasing rebreathing and potential hypercapnia.

Venturi mask (air-entrainment mask). It uses adapters to entrain specific air-oxygen ratios, providing controlled FiO2 (24-50%) ideal for patients sensitive to high oxygen levels.