• lungs representing deadspace ventilation
    Calculations

    Vd/Vt

    The Vd/Vt indicates how much of the tidal volume is composed of deadspace. This is important to monitor because increases in deadspace reduce gas exchange and increase the patient’s work of breathing. Vd/Vt = PaCO2-PECO2/PaCO2Peco2 [...]
  • oxygen pressure
    RRT Exam Prep

    A-a Gradient

    The A-a gradient compares the pressure of oxygen in the alveoli (PAO2) to the pressure of oxygen in the arteries (PaO2). This pressure difference should range between 5 and 10 mm Hg in a healthy [...]
  • carbohydrates, protein, fats
    Calculations

    Respiratory Quotient

    What is the respiratory quotient? The respiratory quotient (RQ) is the ratio of carbon dioxide produced to oxygen consumed. This is based primarily on the patient’s diet. A diet high in lipids has an RQ [...]
  • Oxygen masks
    Calculations

    PaO2/FiO2 Ratio

    The PaO2/FiO2 ratio, also known as the P/F ratio, is a quick calculation often used to determine the severity of ARDS. The P/F ratio is calculated by dividing the arterial oxygen pressure (PaO2) obtained from [...]
  • alveolar gas exchange
    Calculations

    Alveolar air equation

    The alveolar air equation calculates the partial pressure of oxygen within the alveoli (PAO2). The alveolar air equation is also referred to as the alveolar gas equation. PAO2 = [(Patm – Ph2O)fio2] – [PaCO2/0.8] Why [...]
carbohydrates, protein, fats
In the Spotlight

Respiratory Quotient

by DW in Calculations 0

What is the respiratory quotient? The respiratory quotient (RQ) is the ratio of carbon dioxide produced to oxygen consumed. This is based primarily on the patient’s diet. A diet high in lipids has an RQ [...]

Basic Waveform Analysis