1240 
MONITORING 
advantages of continuous measurement availa- 
ble, but v^^ith two catheters in place, several 
additional hemodynamic variables can be moni- 
tored, including cardiac output, arterial pres- 
sure, and central venous pressure. 
SUMMARY 
Measurement of basic cardiovascular param- 
eters, pressure, flow, ECG, and blood gas (O2 
saturation and pH) is discussed. A simple but 
reliable method for obtaining the ECG is de- 
scribed. A new and more accurate method of 
measuring venous pressure under exercise con- 
ditions by using a pulsed catheter tip transducer 
is available. In flow measurement, there are 
average direct measurement methods of deter- 
mining in vivo flow, particularly cardiac output, 
but instantaneous flow measurement methods 
(electromagnetic flowmeter, Doppler ultrasonic 
flowmeter) have become practical, reliable 
methods with recent improvements. The electro- 
magnetic flowmeter now has two features, pre- 
calibrated probes and an electrical or non-occlu- 
sive zero, which give it the ability to directly 
measure any in vivo flow. 
A new solid-state fiberoptics oximeter has not 
only the advantages of continuous Oo satura- 
tion measurement without withdrawing blood 
samples, but also the capability for measure- 
ment of pressure through a lumen in the cath- 
eter. 
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DISCUSSION 
K. Sagawa, Johns Hopkins Medical School, 
Baltimore : I'm very glad to hear about your ef- 
