Oxygen consumption meter

Claim 1

An indirect calorimeter operative to measure the respiratory oxygen consumption from respiratory gases per unit time of a subject, comprising: a respiratory connector operative to be supported in contact with the subject so as to pass said respiratory gases as the subject breathes into said respiratory connector; a scrubber having a gas inlet and a gas outlet and constructed to absorb carbon dioxide from said respiratory gases passing between its inlet and outlet; flow meter means operatively connected to said respiratory connector for generating signals as a function of the gas volume of said gases passed through said meter means; valves and conduits interconnecting said respiratory connector, scrubber, and flow meter means, and constructed such that upon the subject inhaling, gas is caused to pass through the scrubber, then through the flow meter means, and then to the subject's respiratory system through the respiratory connector, and upon the subject exhaling to pass the exhaled gas from the respiratory connector first through scrubber, then through the flow meter means; means for receiving the resultant signals from the flow meter means and for generating a signal proportional to the integral of the differences between the inhaled and exhaled gas volumes over a period of time; and means for connecting said conduits to a mechanical ventilator so that the ventilator may provide respiratory gas to the calorimeter and receive exhaled gas from the calorimeter.