Metabolic Demand, V/Q Distributions and Gas Exchange

This simulation examines the effects of metabolic demand (oxygen consumption and carbon dioxide production) and the shape of the V/Q distribution on the arterial blood gases and several gas exchange parameters. It uses an 11 compartment model and each compartment has a unique V/Q ratio ranging from zero to infinity.

First, create the V/Q distribution by adjusting the perfusion (%Q) to each compartment below. Click on the compartment perfusion bar and drag it horizontally until the desired fractional perfusion is achieved. The total fractional distribution will always sum to one, so increasing the fractional perfusion to one compartment will automatically decrease the fractional perfusion of the other compartments proportionally. To lock any compartment perfusion at a given value, click on the associated lock. The deadspace compartment (V/Q=infinity) is unperfused; its slider specifies the fraction of total ventilation that is distibuted to the deadspace compartment and does not affect the remaining perfusion distribution.

V/Q Perfusion Distribution
+-- Compartment V/Q -------------------------------------------------------- % Q

Next, please enter the following parameters:

VO2 ( > 50 mls/min )
VCO2 ( > 50 mls/min )
cardiac output ( 0.1 - 30 L/min )
blood hemoglobin concentration ( 1 - 20 gm/dl )
body temperature ( 30 - 43 oC )
barometric pressure ( 300 - 1520 mmHg )
FIO2 ( 0.05 - 1.0 )






V/Q %Q pH PO2 PCO2 PN2 O2 con CO2 con R