What is the formula for PAO2?

The alveolar gas equation is used to calculate alveolar oxygen partial pressure: PAO2 = (Patm – PH2O) FiO2 – PACO2 / RQ.

How do you calculate PaCO2?

III. Calculation: Calculated PaCO2 in Metabolic Conditions

  1. Metabolic Acidosis with expected compensation. PaCO2 = 1.5 x HCO3 + 8 (+/- 2) PaCO2Delta = 1.2 x BicarbDelta. PaCO2 will not typically drop below 10 mmHg in respiratory compensation.
  2. Metabolic Alkalosis with expected compensation. PaCO2 = 0.7 x HCO3 + 20 (+/- 1.5)

How is PiO2 calculated?

  1. PiO2 = FiO2 x (barometric pressure – saturated vapour pressure of H20)
  2. PiO2 = 0.21 x (760 – 47) – sea level.
  3. PiO2 = 150mmHg.
  4. gas supply pressures are continuously measured.
  5. FiO2 is monitored within the inspiratory limb of ventilators.

What should PAO2 be on oxygen?

The PaO2 while breathing room air should be 10.0 – 13.0 kPa. However, if the patient is receiving supplemental oxygen, the PaO2 must be interpreted in light of the inspired oxygen concentration.

How do you calculate ph20?

The formula used for this calculation, PH2O = Patm – Pair , must include the corrected volume in liters and temperature in Kelvin. edition. Make sure to convert pressure to atmospheres. Calculate the theoretical ∆Hvap for water from the given literature values.

How do you calculate pCO2?

In contrast, the equation pCO2 = 1.5 × HCO3 + 8, known as Winters’ formula, exhibits larger errors.

Is PAO2 and PO2 the same?

PO2 , SaO2 , CaO2 are all related but different. PaO2, the partial pressure of oxygen in the arterial blood, is determined solely by the pressure of inhaled oxygen (the PIO2), the PaCO2, and the architecture of the lungs.

Is PIO2 the same as PAO2?

PaO2, the partial pressure of oxygen in the arterial blood, is determined solely by the pressure of inhaled oxygen (the PIO2), the PaCO2, and the architecture of the lungs.

How do you calculate PAO2 FiO2 ratio?

P divided by F = P/F ratio. Example: PaO2 = 90 on 40% oxygen (FIO2 = 0.40): 90 / 0.40 = P/F ratio = 225. A P/F ratio of 225 is equivalent to a pO2 of 45 mmHg, which is significantly < 60 mmHg on room air.

What is a normal PaO2?

Normal Results Partial pressure of oxygen (PaO2): 75 to 100 millimeters of mercury (mm Hg), or 10.5 to 13.5 kilopascal (kPa) Partial pressure of carbon dioxide (PaCO2): 38 to 42 mm Hg (5.1 to 5.6 kPa) Arterial blood pH: 7.38 to 7.42.