Respiratory Therapy Equations – Flashcards
Unlock all answers in this set
Unlock answersquestion
Alveolar Oxygen Content
answer
PAO2= FIO2 (Pb-47) - (PaCO2/0.8)
question
%Body Humidity
answer
(Absolute Humidity/43.8) x100
question
%Relative Humidity
answer
(AH/Saturated Capacity) x100
question
Oxygen Consumption
answer
VO2= QT [C (a-v) O2] x 10
question
Oxygen Extraction Ratio
answer
O2ER= CaO2-CvO2/ CaO2
question
Hb Saturation
answer
SaO2= [Hbo2/Total Hb] x100
question
A-a Oxygen Tension Gradient
answer
P (A-a) O2= PAO2-PaO2
question
Oxygen Content of Arterial Blood
answer
CaO2= (Hbx 1.34x SaO2) + (PaO2 x 0.003)
question
Oxygen Content of Mixed Venous Blood
answer
CvO2= (Hb x 1.34 x SvO2) + (PvO2 x 0.003)
question
Oxygen Content of Pulmonary Capillary Blood
answer
CcO2= (Hb x 1.34X SaO2) + (PaO2 x 0.003)
question
Total Oxygen Delivery
answer
DO2= QT (CaO2 x 10)
question
Pulmonary Shunt Fraction
answer
Qs/Qt= CcO2-CaO2/CcO2- CvO2
question
Arterial- Venous Oxygen Content Difference
answer
C(a-v) O2 = CaO2- CvO2
question
Farenheight to Celsius
answer
F-32= 1.8 (C)
question
Kelvin
answer
K= C+273
question
Boyle's Law
answer
P1 x V1= P2 x V2
question
Charles' Law
answer
V1/T1= V2/T2
question
Guy-Lussac's
answer
P1/T1= P2/T2
question
Combined Gas Law
answer
(P1x V1)/ T1= (P2 x V2)/ T2
question
Minute Ventilation
answer
Vt (tidal volume) x RR (respiratory rate)
question
Ideal Body Weight
answer
Male: 106 +6 (Height in inches -60) Female: 105 +5 (Height in inches - 60)
question
Duration of Flow (min)
answer
Duration of Flow (min)= Pressure (psig) x cylinder factor/ Flow (L/min)
question
Amount of Gas in Cylinder
answer
Liquid O2= weight(lb) x 860/ 2.5 lb/L
question
Duration of Gas (min)
answer
Amount of Gas in Cylinder(L)/ Flow (L/min)
question
%O2
answer
(Air Flow x 21) + (O2 Flow x 100)/ Total Flow
question
Cylinder Factor (L/psig)
answer
Cubic Feet (full cylinder) x 28.3/ Pressure(full cylinder) in psig
question
Shunt Equation w. or w/o CPAP
answer
Qs/Qt= CcO2-CaO2/5+CcO2- CvO2
question
Shunt Equation w. or w/o PEEP
answer
Qs/Qt= CcO2-CaO2/3.5+CcO2- CvO2
question
Shunt Equation : Modified
answer
Qs/Qt= (PAO2- PaO2) x 0.003/(CaO2- CvO2)+ (PAO2-PaO2) x 0.003
question
Anion Gap
answer
Agap =Na+ -(Cl- +HCO3-)
question
Arterial/Alveolar Oxygen Tension (a/A) Ratio
answer
a/A = PaO2 /PAO2
question
Arterial-Mixed Venous Oxygen Content Difference
answer
[C (a - v) O2]
question
amount of O2 dissolved in 100mL
answer
PaO2 x 0.003
