Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
1
Common Respiratory Care Equations
% Accuracy:
% Accuracy =
Mean measured value
reference value
× 100
% Error:
% Error =
Mean measured value−Reference value
Reference value
× 100
%Body Humidity:
%BH = (AH/43.8) × 100
Acute Alveolar Hyperventilation:
∆HCO−
3 = 0.2 × ∆PaCO2
Acute Alveolar Hypoventilation:
∆HCO−
3 = 0.10 × ∆PaCO2
Adjusting Oxygen Percentage:
PaO2 desired
FI O2 = (PaO
2 /PAO2
+ PaCO2 × 1.25) × P
ratio
1
B −PH2O
Simpler but less accurate:
PaO2 (initial)
FI O2 (Initial)
=
PaO2 (Desired)
FI O2 (New)
Notes: Where PaO2 (initial) is the current arterial the current arterial oxygen tension (mm Hg),
the FIO2 (initial) is the current setting for the fraction of inspired oxygen, the PaO2 (desired) is
the arterial oxygen tension (mm Hg) that is desired, and the FIO2 (new) is the setting for the
fraction of inspired oxygen.
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
2
Adjusting Ventilation:
PaCO2 (1) × VT (1) = PaCO2 (2) × VT (2)
Notes: Where PaCO2 (1) is the initial arterial carbon dioxide tension (mm Hg), VT (1) is the
current tidal volume (L), PaCO2 (2) is the desired carbon dioxide tension (mm Hg), and VT (2)
is the new tidal volume setting (L).
Air-to-oxygen ratio:
Liters air
Liters O2
=
(100−%O2 )
(%O2 −21)
Notes: Where the flow rate values are the settings on the flow meters. The air-to-oxygen ration
for each oxygen concentration is a fixed value. The “magic box” is a visual method of making
this same calculation:
100 − %O2
21
%O2
100
%O2 − 21
Airway Pressure:
Paw = Elastance (Vt ) + Resistance (flow)
Airway Resistance:
Raw =
PIP−PPlateau
Flow
Notes: Where Raw (cm H2O/L/s) is the airways resistance, PIP is the peak inspiratory pressure
(cm H2O), Pplateau is the plateau pressure (cm H2O). The presence of an artificial airway changes
the airways resistance. This measurement if easily assessed on patients receiving ventilator
support. A constant flow pattern (square) should be used for this measurement. Remember that
ventilators normally report the flow rate in L/min and this value needs to be converted to L/s.
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
3
Alveolar Air Equation:
PAO2 = FI O2 (PB − PH2O ) − [PACO2 × {FI O2 + (1 −
FI O2
R
)}]
simplified form: PAO2 = PI O2 − (PACO2 × 1.25)
Notes: Where PAO2 partial pressure of alveolar oxygen PACO2 partial pressure of alveolar
carbon dioxide. The I refers to inspired. Thus, FIO2 is the fraction of inspired oxygen. Think of
a fraction as changing the percentage of a value into a decimal. Divide the percentage by 100 to
get the FIO2.
Alveolar Carbon Dioxide Tension:
PaCO2 =
̇ 2 ×0.863
VCO
V̇A
̇ 2 is the CO2
Notes: Where PaCO2 is the partial pressure of alveolar carbon dioxide (mm Hg), VCO
production (mL/Min), V̇A is alveolar ventilation (L/min), and .863 is the factor to convert
temperature from STPD to BTPS.
Alveolar Partial Pressure of Oxygen:
PAO2 = FI O2 × (PB − 47) − (PACO2 ÷ 0.8)
Alveolar Pressure:
PA =
∆V
CS
Alveolar Ventilation:
V̇A = (VT − VDSphys )ƒ
Notes: Where V̇A is alveolar ventilation (L/min), VT - VDSphys is = VA , and ƒ is frequency
(breaths/min).
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
4
Amount of Oxygen Carried by the Hemoglobin:
1.34(
mL
g
g
) × Hb(dL) × SaO2 (%)
Notes: Each gram of hemoglobin (Hb) carries 1.34
g
mL
g
of oxygen. The average hemoglobin
concentration is 15 dL. The SaO2 is the percentage of hemoglobin bound with oxygen.
Anion Gap:
Anion gap = [Na+ ] − ([CI− ] + [HCO3 − ])
Arm Muscle Area:
AMA (males) =
[MAC−(π×TSF)]2
𝐴𝑀𝐴 (𝑓𝑒𝑚𝑎𝑙𝑒𝑠) =
4π
− 10 cm
[𝑀𝐴𝐶 − (𝜋 × 𝑇𝑆𝐹)]2
− 6.5𝑐𝑚
4𝜋
Notes: AMA is the arm muscle area, MAC is the mid-arm circumference, and TSF is the triceps
skinfold thickness (TSF) which is a measure of body fat.
Arterial Partial Pressure of Carbon Dioxide:
PaCO2 =
0.863×V̇CO2
V̇A
Body Mass:
weight (kg)
BMI = height (m)2
or
weight (lb)
BMI = height (in)2 × 704.5
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
5
Boyle’s Law:
P×V=K
<rule>
Buoyancy:
B = dw × V
Notes: Where B is buoyancy, dw is the weight density of object and V is the object’s volume.
Carbon Dioxide Production:
V̇CO2 = FE̅ CO2 × V̇E
Notes: Where the V̇CO2 (mL/min) is the CO2 production, the FE̅ CO2 is the average value of
expired carbon dioxide, and the V̇E (mL/min) is the expired minute ventilation. a) There is no
need to measure FI CO2 because the amount of inhaled carbon dioxide is very small.
TheFE̅ CO2 is measured by collecting expired gas in a large reservoir such as a Douglas bag.
Newer capnometers use microprocessors to calculate the average (mixed) carbon dioxide value
from individual breaths.
Cardiac Index:
cardiac output
CI = body surface area
Cardiac Output:
CO = Stoke volume × Heart rate
Notes: In clinical practice, the CO is measured by Fick equation (see later in document), the
thermodilution through a pulmonary artery catheter (Swan-Ganz), and is estimated by
transesophageal echocardiography.
Celsius to Kelvin:
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
6
°K = °C + 273
Cerebral Perfusion Pressure (CPP):
CPP = ICP − MAP
Notes: Where ICP is intracranial pressure and MAP is mean arterial blood pressure.
Charles’ Law:
V
T
=K
Combined Gas Law:
P1 ×V1
T1
=
P2 ×V2
T2
Notes: Where P is pressure, V is volume, T is Temperature. Remember that if water vapor is
present, subtract this from the pressure and the temperature needs to be converted to °K.
Compliance:
tidal volume
Compliance = plateau pressure−PEEP
Corrected Pressure:
PC = Fgas × (PT − PH2 O )
Current:
Current (A) =
Voltage (V)
Resistance (Ω)
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
7
Cylinder Factor: (see also Gas Cylinders)
Cubic feet (full cylinder)×28.3
Cylinder Factor (L/psig) = Pressure (full cylinder)in psig
Dalton’s Law:
Partial Pressure = Fractional Concentration × Total Pressure
Dead Space to Tidal Volume Ratio:
VD
VT
=
PaCO2 −PE
̅ CO2
PaCO2
V
Notes: Where VD is the dead space tot tidal volume ration (%), PaCO2 is the partial pressure of
T
arterial carbon dioxide (mmHg), andPE̅ CO2 is the partial pressure of mixed expired carbon
dioxide (mm Hg). The measurement for PE̅ CO2 is a mixed expired carbon dioxide value. This
value can be measured by collecting expired gas in a large reservoir such as a Douglas bag.
Newer capnometers use microprocessors to calculate the average (mixed) carbon dioxide value
from individual breaths.
Dead Space Ventilation:
V̇D = VD × ƒ
Notes: Where V̇D is dead space ventilation (L/min), VD is dead space volume (L), and ƒ if
frequency (breaths/min).
Density:
d=
m
V
Notes: Where d is the density, m is the object’s mass, and V is the volume the mass occupies. In
clinical practice, weight is used for the mass which provides a weight density dw
and for gases, mass is measured by gmw and the volume is expressed in liters.
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
8
or
weight
dw = volume
Notes: Where dw is the weight density.
Desired Fractional Inspired Oxygen:
Desired FI O2 =
[PaO2 (desired)×FI O2 (known)]
PaO2 (known)
Desire Respiratory Rate:
Desired ƒ =
Known PaCO2 ×Known ƒ
Desired PaCO2
Desired Tidal Volume:
Desired VT =
Known PaCO2 ×Known VT
Desired PaCO2
deWeir Equation:
EE = [3.941 (V̇O2 ) + 1.106 (V̇CO2 )] × 1.44 − [2.17 (urinary nitrogen)]
Diffusion Capacity of the Lung for Carbon Monoxide (DLCO):
DLCO = VE (FI CO − FE CO) ÷ (PACO)
Diffusion Capacity of the Lung for Carbon Monoxide by a Single Breath:
DLCOSB = [60(VA ) ÷ t(PB − 47)] × in (FACO0 ÷ FACOt )
Dilution:
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
9
V1 C1 = V2 C2
Drug Dosage:
Drug Solute (in g)
%(as decimal) = Total solution (in ml)
Duration of Flow of a Cylinder: (see also Gas Cylinder)
Duration of Flow (min) =
Pressure (psig)×Cylinder Factor
Flow (L/min)
Duration of Gas: (see also Gas Cylinder)
Duration of gas (min) =
Amount of gas in cylinder (L)
Flow (L/min)
Dynamic Compliance:
VT
PIP − PEEP
Efficiency of Ventilation for Single Breath:
VT = VA + VD
Effective Total Lung Capacity:
VA = VC × (FIHe ÷ FEHe)
Ejection Fraction:
SV
EF = EDV
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
10
Notes: Where EF is ejection fraction (%), SV is stroke volume (mL), and EDV is end-diastolic
volume (mL).
Enghoff-Modified Bohr Equation:
[PaCO2 − PE̅ CO2 ]/PaCO2 = VD /VT
Equation of Motion:
Pvent + Pmus = (E × V) + (R × V̇)
Notes: Where Pvent is the pressure (cm H2O) used by the ventilator, Pmus is the pressure (cm H2O)
the respiratory muscles create, E is elastance, R is resistance, and V̇ is the flow rate (L/min).
Estimated Tidal Volume:
VT = (TI × VL̇/min)
60
Fahrenheit to Kelvin:
°C = 5/9 ×(°F − 32) then °K = °C − 273
Fick Equation:
Q̇t = V̇O2 ÷ [C(a − v̅)O2 × 10]
Notes: The basic formula for Fick's first law of diffusion addresses the rate of diffusion across a
membrane. This diffusion rate is affected by the membrane's area, diffusion constant, and the
concentration gradients on both sides of the membrane.
Fick’s First Law of Diffusion:
V̇gas = [(A × D × S) ÷ T](P1 − P2 )
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
11
Notes: Where V̇gas is gas transport across the membrane, A is the cross-sectional area for
diffusion, D is the diffusion coefficient of the gas, S is the solubility of the gas, T is the thickness
of the membrane, andP1 − P2 is the pressure gradient across the membrame. When applying this
equation to the lungs, the concentration gradient in Fick's diffusion equation is calculated by
using Henry's law. The volume of gas is affected by the solubility (S) and partial pressure (P).
Flow Resistance:
R=
(P1 −P2 )
V̇
Flow Rate:
V
V̇ = t
Notes: Where V̇ is flow rate (L/min or L/s), V is volume (L), and t is time (min or s).
or
P
V̇ = R
Notes: Where V̇ is flow rate (L/s), P is pressure (cm H2O), and R is resistance.
Fractional Hemoglobin Saturation:
Fractional O2 Hb = [HHb+O
O2 Hb
2 Hb+COHb+MetHb]
Functional Residual Capacity (FRC):
FRC = (vol He ÷ Fi He) × [(Fi He − Fƒ He) ÷ Fƒ He]
FRC (or TLC) by Nitrogen Washout Technique:
FRC = (VE × FE N2 ) ÷ (0.78 − FA N2 )
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
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Functional Hemoglobin Saturation:
O Hb
2
Functional O2 Hb = [HHb+O
2 Hb]
Gas Cylinders
Duration of flow = Cylinder pressure × Cylinder factor x
1
flow rate
Notes: Where units of measure are duration of flow (min), cylinder pressure (psig), cylinder
factors (L/psig), and flow rate (L/min). The cylinder factor for an H cylinder of oxygen is 3.14
L/psig. The cylinder factor of an E cylinder of oxygen is 0.28 L/psig. Use a cylinder pressure of
200 psig lower than the actual cylinder pressure for patient safety. It is dangerous for patients
when tanks empty earlier than expected. Most full cylinders contain 2200 psig.
Gas in Liquid O2 Cylinder:
Amount of gas in cylinder =
Liquid O2 weight (b)×860
2.5lb/L
Gas Mixing:
VF CF = V1 C1 + V2 C2
Gay-Lussac’s Law:
P
T
=K
Graham’s Law:
Dgas =
1
√gmw
Notes: Where Dgas is the diffusion rate of the gas, and gmw is the gram molecular weight.
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
13
Gram Equivalent Weight Value:
gEq =
Gram atomic (formula)weight
Valence
Harris-Benedict Equation:
men: BEE = 66 + (13.7)(weight) + (5)(height) − (6.8)(age)
women: BEE = 65 + (9.6)(weight) + (1.8)(height) − (4.7)(age)
Heat Gain/Loss by Radiation:
E
t
= ekA(T2 − T1 )
Hemoglobin Saturation:
SAO2 = [HbO2 ÷ Total HB] × 100
Henderson-Hasselbach Equation:
pH = pK + log[(HCO−
3 )/(H2 CO3 )]
simplified form: [H + ] =
24×PaCO2 (mm Hg)
HCO3 − (mEq/L)
Notes: Where HCO−
3 is bicarbonate and H2 CO3 is carbonic acid. In clinical practice
The carbonic acid is not measured directly. This value is estimated by measuring the amount of
dissolved carbon dioxide. The ratio is base ( HCO−
3 ) to acid ( H2 CO3 or CO2 ) needs to be 20:1
for a pH = 7.40.
Henry’s Law:
V = α × Pgas
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
14
Notes: Where V is the volume of the dissolved gas, is the solubility coefficient and Pgas is the
partial pressure of the gas above the liquid. At higher temperatures, the gases are less soluble.
The higher kinetic energy makes the gas escape from the solution. The solubility of oxygen at
body temperature (37°C) is 0.003 mL/ mmHg/dL. Therefore:
Dissolved oxygen = PaO2 × 0.003 mL/ mmHg/dL.
Ideal Body Weight:
men: IBW (lbs) = 106 + 6[height (in) − 60]
women: IBW (lbs) = 105 + 5[height (in) − 60]
Inspiratory Resistance:
Raw = ∆P/∆F =
(Ppeak −Pplat )
flow
Karvonen Formula:
[(HR max − HR rest ) × (50% to 70%)] + HR rest
Notes: Where HR max is the patient’s maximal heart rate and HR rest is the resting heart rate.
Laminar Flow:
P = K1 × V̇
Laplace’s Law:
As applied to a drop
P=
2ST
r
As applied to a bubble
P=
4ST
r
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
15
As applied to a cylinder
P=
ST
r
Notes: Where P is the pressure inside the liquid bubble, ST is the surface tension, and r is the
radius of the bubble.
Law of Continuity:
(A1 × v1 ) + (A2 × v2 ) + (An × vn ) = k
Left Ventricular Stroke Work:
LVSW = (MAP × SV) × 0.0136
Liquid Pressure:
PL = h × dw
Notes: Where PL is the liquid’s static pressure, h is the height of the liquid and dw is the weight
density.
Lung Compliance:
∆V (liters)
CL = ∆P
pl
(cm H2 O)
Notes: Where CL is the compliance (L/cm H2O) for the lung. ∆V (L) is the change in volume
from the beginning to the end of inspiration. ∆Ppl (cm H2O) is the change in pressure from the
beginning to the end of inspiration.
Mean Airway Pressure:
1
inspiratory time
Paw
̅̅̅̅ = 2 [PIP × (total respiratory cycle)]
or
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
16
1
inspiratory time
Paw
̅̅̅̅ = 2 (PIP − PEEP) × ( total cycle time ) + PEEP
Notes: Where Paw
̅̅̅̅ is the mean airway pressure, PIP is the peak inspiratory pressure (cm H2O).
Mean Arterial Blood Pressure:
MAP =
SBP+(2×DBP)
3
Notes: Where MAP is mean arterial pressure (mm Hg), SBP is systolic blood pressure (mm Hg),
and DBO is diastolic blood pressure (mm Hg).
Mean Arterial Pressure:
Volume
Mean Arterial Pressure = Capacity
<rule>
Mechanical Dead Space to Add:
PaCO2(1) (VT −VD −VDmech(1) )
VDmech(2) = VT − VDphys − (
PaCO2(2)
)
Milligram Equivalent Weight:
gEq
mEq = 1000
Minute Ventilation:
V̇E = VT × 𝑓
Notes: Where V̇E is minute ventilation (L/min), VT is tidal volume (L), and f is breaths/min.
Modified Fick Equation:
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
17
kcal
REE (
) = Cardiac Output × Hemoglobin × (SaO2 − Sv̅O2 ) × 95.18
day
Modified deWeir Equation:
Notes: Where REE (kcal/day) is the resting energy expenditure,
consumption, and
(mL/min) is the O2
is the CO2 production. This equation is used to predict the patient’s
caloric needs at rest.
Nitrogen Balance:
Ohm’s Law:
Notes: The current is measured in amperes (A), voltage is measured in volts (V), and resistance
is measures in Ohms (Ω).
Oxygen Consumption:
Oxygen Consumption by Ventilatory Muscles:
(Arterial) Oxygen Content:
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
18
Notes: Where CaO2 is the arterial oxygen content (mL/dL), Hb is the total hemoglobin (g/dL),
and SaO2 is the percentage of hemoglobin saturated with oxygen (%).
Oxygen Cost of Breathing:
Oxygen Delivery:
Notes: Where DO2 is oxygen delivery (mL/min), CaO2 is the arterial oxygen content (mL/dL).
Oxygen Flow:
Oxygen Percentage:
Notes: Where the air flow rate is the reading from the air flowmeter (L/min), the O2 flow rate is
the reading from the oxygen flowmeter (L/min), and the total flow rate is the sum of the readings
from the air and oxygen flowmeters.
Pack Years:
Partial Pressure of Alveolar Nitrogen:
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
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Partial Pressure of Inspired Oxygen:
Passive Inhalation:
Percent Gas Exhaled:
Percent Leak:
Percent leak = [
(VT insp − VT exh)
VT insp
Percentage Shunt:
pH:
Physically Dissolved Oxygen:
× 100]
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
20
Physiologic Dead Space:
Physiologic Shunt:
Notes: Where
is the ratio of shunted blood to the total cardiac output, the
is the oxygen content (mL/dL) measured from a pulmonary capillary (end-capillary) blood
sample, the
is the oxygen content (mL/dL) from an arterial blood sample, and the
the oxygen content (mL/dL) from a mixed-venous blood sample.
Poiseuille’s Law:
Notes: Where
length,
is the driving pressure gradient, n is the viscosity of the fluid, l is the tube’s
is the fluid’s flow rate, and r is the tube’s radius.
Predicted PaO2 with Age:
Predicted Postoperative Value:
Notes: Patients need at least a 40% predicted postoperative value to tolerate surgery.
is
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
21
Pressure:
Pressure Support:
Pressure Support Ventilation to overcome WOBI:
Pressure-Time Index:
Pulmonary Function Impairment:
Pulmonary Function Improvement:
Notes: Where “Pre” is the pulmonary function variable before a bronchodilator and “Post” is the
pulmonary function variable after using a bronchodilator. The calculation is used to determine
how much the pulmonary function variable improved after taking a bronchodilator.
Pulmonary Vascular Resistance:
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
22
Notes: Where PVR is pulmonary vascular resistance, MPAP is mean pulmonary artery pressure
and MLAP is mean left atrial pressure. Cardiac output is the same as pulmonary blood flow.
You must look at the pressure that it takes to move the blood through the pulmonary circulation.
Multiply by 80 to convert from
to
Rapid, Shallow Breathing Index:
Notes: Where RSBI is the rapid, shallow breathing index (breaths/min/L), ƒ is the respiratory
rate (breaths/min), and VT is the tidal volume (L).
Relative Humidity:
Respiratory Exchange Ratio:
Notes: Where R is the respiratory exchange ratio,
is the O2 consumption (mL/min) and
is the CO2 carbon dioxide production (mL/min).
Respiratory Quotient:
Notes: Where RQ refers to the respiratory quotient, RQ refers to the ratio of
tissues. This ratio at complete rest is treated as an RQ measurement.
Respiratory Rate:
to
in the
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
23
Resting Energy Expenditure (REE):
men:
women:
Required Frequency:
Reynold’s Number:
Right Ventricular Stroke Work:
RV:
Spontaneous Tidal Volume:
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
24
Starling Equilibrium:
Notes: Where
is the flow of fluid between the capillaries and interstitial space,
is the
capillary permeability coefficient for fluids and electrolytes,
is the capillary hydrostatic
pressure,
is the interstial fluid hydrostatic pressure,
is the capillary permeability
coefficient for proteins,
is the capillary oncotic pressure, and
is the interstitial fluid
oncotic pressure. On the arterial side: fluid, oxygen, and nutrients are pushed toward cells and
into the interstitial fluid. On the venous side: fluid, carbon dioxide, and cellular waste products
are pulled into the capillaries. Excess fluid in the interstitial space is absorbed into the lymphatic
system.
Static Compliance:
Stroke Index:
Stroke Volume:
Systemic Vascular Resistance:
Notes: Where SVR is systemic vascular resistance.
Thoracic Gas Volume:
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Tidal Volume:
Time Constant:
Notes: Where C is compliance (L/cm H2O) and R is resistance (cm H2O)/L/s)
TLC:
Total Compliance:
Total Cycle Time:
Total Oxygen Content:
Total PEEP:
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Egan’s Fundamentals of Respiratory Care, 10th Edition
26
Tracheal Pressure:
Transairway Pressure:
Transitional Flow:
Transpulmonary Pressure:
Notes: Where
is transpulmonary pressure,
is transairway pressure and
is
transalveolar pressure
Transpulmonary Pressure Gradient:
Notes: Where
is transpulmonary pressure,
Transrespiratory Pressure Gradient:
Transthoracic Pressure Gradient:
is alveolar pressure and
is pleural pressure.
Formulas
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27
Turbulent Flow:
Vascular Resistance:
Ventilatory Equivalent for Carbon Dioxide:
𝑉̇𝐸
𝑉̇ 𝐶𝑂2
Notes: Where 𝑉̇𝐸 is the expired minute ventilation(mL/min) and 𝑉̇ 𝐶𝑂2 is the O2 consumption
(mL/min).
Ventilatory Equivalent for Oxygen:
𝑉̇𝐸
𝑉̇ 𝑂2
Notes: Where 𝑉̇𝐸 is the expired minute ventilation(mL/min) and 𝑉̇ 𝑂2 is the O2 consumption
(mL/min).
Ventilatory Reserve:
Formulas
Egan’s Fundamentals of Respiratory Care, 10th Edition
28
Notes: Where ventilator capacity (L/min) is measured by the maximum voluntary ventilation
(MVV) or by multiplying the FEV1 by 40, and the
(L/min) is the highest minute
ventilation that occurs at the end of a cardiopulmonary exercise test.
Volume:
Volume Lost:
Work of Breathing:
Work of Breathing Provided by Ventilator: