[Continuous pH registration in the coronary sinus in vivo in ischemic and normoxic lactic acidosis using an ion sensitive field effect transistor catheter].
A new catheter with an Ion Sensitive Field Effect Transistor (ISFET) for continuous measurements of blood pH in vivo was employed. In canine heart preparations (n = 15), two catheters were positioned in the coronary sinus and in the abdominal aorta, respectively. A close agreement between pH-measurements with the pH-ISFET-sensor and the corresponding pH-determinations on blood samples by conventional means (r = 0.97; pH-range 7.15-7.50) was found. The ISFET-sensor revealed a sensitivity of 50-55 mV/pH, a long-term drift rate of 1-2 mV/h, as well as a response time shorter than 100 ms. The ISFET-sensor was sensitive for the detection of respiratory and metabolic acidosis and alkalosis (hypo-, hyperventilation, myocardial ischemia, intracoronary infusion of 0.3-M lactic acid). There was a close correlation between the changes of coronary venous pH and lactate concentrations during myocardial ischemia (r = 0.83; n = 9). During ischemic acidosis there was a drastic reduction of left ventricular dp/dtmax, whereas contractility changes during normoxic lactacidosis were moderate. The pH-decrease (pH = 7.1) was identical in both interventions. The observed data suggest that the newly developed ISFET-pH-catheter is working precisely and enables respiratory and metabolic control of the whole organism as well as of individual organs.
Frombach
R
R
Abteilung für Kardiologie des Zentrums Innere Medizin und Dermatologie, Medizinischen Hochschule Hannover, F.R.G.
Reil
G H
GH
Hiltermann
G
G
Ligtenberg
H C
HC
Lichtlen
P R
PR
D000136:Acid-Base Equilibrium; D000140:Acidosis, Lactic / Q000503:physiopathology*; D000818:Animals; D001784:Blood Gas Analysis / Q000295:instrumentation; D006328:Cardiac Catheterization / Q000295:instrumentation*; D003327:Coronary Disease / Q000503:physiopathology*; D004285:Dogs; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000097:blood; D019344:Lactic Acid; D009200:Myocardial Contraction; D009206:Myocardium / Q000378:metabolism
D007773:Lactates; D019344:Lactic Acid
Kontinuierliche pH-Registrierungen im Koronarsinus in vivo bei ischämischer und normoxischer Laktazidose mittels eines ISFET-Katheters.