top of page

terminology

Look up all terms that you want to know about

Try clicking on the             to learn more about an item.

A

ASV

Adaptive Support Ventilation
Available on Hamilton(TM) ventilators

Asynchrony Index

Total asynchrony events / total breaths * 100

BAL

Broncho-Alveolar Lavage

BMR

Basic metabolic rate

CMV

Conventional Mechanical Ventilation

CPAP

Continuous Positive Airway Pressure

CXR

Chest X-Ray

Cl-

Chloride

Cycling

Terminating a breath

DO2

Oxygen Delivery
DO2 = CO x SaO2 x Hb + (paO2 x 0.03)

EELV

End-Expiratory Lung Volume

ETT

Endotracheal Tube

F

FEV1

Forced Expiratory Volume in the first second

FiO2

Fraction of Inspired Oxygen

H

HFOV

High Frequency Oscillatory Ventilation

Hb

Hemoglobin

I

IC

Inspiratory Capacity

IPPV

Intermittent Positive Pressure Ventilation

IRV

Inspiratory Reserve Volume

K

L

LV

Left Ventricle

LVOT

Left Ventricular Outflow Tract

MAP

Mean Airway Pressure = Area under the pressure curve

Na+

Sodium. Dialy requirement 3-4mmol/kg

OI

Oxygenation Index = (MAPxFiO2)/paO2

P

P-SILI

Patient Induced Self-Inflicted Lung Injury

PC

Pressure Control

PEEPi

Intrinsic PEEP = Auto-PEEP

PRP

Pressure Rate Product = PRP = pressure x respiratory rate

PTP

Pressure Time Product = PTP = Pavg × Ti = Average pressure during inspiration x Inspiratory time

Palv

Alveolar Pressure

Paw

Airway Pressure

Pcw

Trans Chestwall pressure

Q

Qp/Qs

Pulmonary to systemic perfusion ratio.
Qp/Qs = (SaO2 - ScvO2) / SpvO2 - SpaO2)

R

Resistance [cmH2O/l/sec]
R=U/I

RM

Recruitment Manouvre

RR

Respiratory Rate

RV

Right Ventricle

Reverse Triggering Index

Total reverse triggering events / total breaths * 100

S/T

Spontaneous / Timed Mode

SIMV

Synchronised Intermittent Mandatory Ventilation

SaO2

Arterial Oxygen Saturation

Shunt

Perfused but not ventilated part of the lung in which V is 0 and P is present. V/Q Ratio is therefore 0.

Stress

Equivalent to Transpulmonary Pressure

T

TVe or Vte

Expiratory Tidal Volume

Ti

Inspiratory Time [sec]

V

VAE

Ventilator Associated Event

VC

Vital Capacity

VILI

Ventilator Induced Lung Injury

VS

Volume Support

W

X

Z

etCO2

End-Tidal CO2

paCO2

Arterial Cardon Dioxide Partial Pressure [mmHg]

A/C

Assist Control

ALI

Acute Lung Injury

ARDS

Acute Respiratory Distress Syndrome

AXR

Abdominal X-Ray

B

BiPAP

Bilevel Positive Airway Pressure

C

CO

Cardiac Output

CSV

Continuous Spontaneous Ventilation

Cdyn

Dynamic Compliance.
Measured while gases are flowing.
C=dV/dP

Cstat

Static Compliance. Measured while no gases flowing.
C=dV/dP

D

E

EE

Energy Expenditure

ERC

Expiratory Reserve Volume

Elastance

Elastance = 1/C = ∆P/∆V

FEV

Forced Expiratory Volume

FRC

Functional Residual Capacity
The lung volume after a normal expiration.

G

HME

Heat and moisture exchange humidifier

Heliox

Helium-Oxygen mix with low density

I (Flow)

Flow [l/sec or l/min]
I=U/R

IMV

Intermittent Mandatory Ventilation

IRV

Inverse Ratio Ventilation

J

K+

Potassium. Daily requirement 1-2mmol/kg

LCOS

Low Cardiac output Syndrome

LVEDP

Left Ventricular End Diastolic Pressure

M

N

NO OR iNO

inhaled nitric oxide

O

OSI

Oxygenation Saturation Index = (MAPxFiO2)/SpO2

P (Power)

Power = Work/time = W/t

P/F Ratio

paO2/FiO2 Ratio.
Mild ARDS 200-300
Moderate ARDS 100-200
Severe ARDS <100

PEEP

Positive End Expiratory Pressure

PS

Pressure Support

Palv

Alveolar Pressure

Pbs

Pressure at Body Surface

Pplat

Plateau Pressure [cmH2O]
Only available in Volume Controlled Ventilation
Represents alveolar pressure

Qp

Pulmonary Blood Flow

Qs

Systemic Blood Flow

R

RQ

Respiratory Quotient (CO2 produced per O2 consumed)
Carbohydrates only: 1.0
Fat only: 0.7
Protein only: 0.8
Balanced Diet: 0.82

RV

Residual Volume

S

SI

Stress Index

ScvO2

Mixed Venous Oxygen Saturation

SpO2

Transcutaneous Oxygen Saturation

SvO2

Venous Oxygen Saturation

TLC

Total Lung Capacity

TV or Vt

Tidal Volume = Volume per breath

TVi or Vti

Inspiratory Tidal Volume

Te

Expiratory Time [sec]

U

V/Q Mismatch

Ventilation / Perfusion Mismatch

VAP

Ventilator-Associated Pneumonia

VC

Volume Control

VO2

Oxygen Consumption
Dependant on Energy Expenditure (EE):
- Body Temperature
- Muscle Activity
- Level of consciousness

Vd

Dead Space

Y

deltaP or ∆P

Pressure Gradient

pARDS

Paediatric Acute Respiratory Distress Syndrome

paO2

Arterial Oxygen Partial Pressure [mmHg]

bottom of page