Subject(s)
Lactates/blood , Oxygen/blood , Animals , Hydrogen-Ion Concentration , Methods , Partial PressureSubject(s)
Congenital Abnormalities/diagnosis , Prenatal Diagnosis , Electrocardiography , Female , Heart Rate , Humans , Labor, Obstetric , PregnancyABSTRACT
The ROCHE pH electrode was tested clinically in 20 fetuses and one nonviable newborn with severe malformations. The proper fixation of the electrode in the fetal scalp is difficult. In the physiologic pH range a good correlation between capillary blood pH and tissue pH exists. The situation is less clear for the acidotic range.
Subject(s)
Electrodes , Fetal Monitoring/instrumentation , Hydrogen-Ion Concentration , Capillaries , Evaluation Studies as Topic , Female , Humans , Hydrogen/blood , PregnancyABSTRACT
1. When chemical sterilization (with Korsolin, Cidex) is performed, a minimal duration of sterilization of 3 h is required for asepsis. 2. Duration of Korsolin sterilization up to 3 h does not influence the in vitro characteristics of the pH-electrode. 3. Sterilization with formaldehyde (24 h, 40 degrees C) is safe, but needs another 24 h restabilization time of the electrode. 4. The temperature dependence of the pH-electrode is minimal. With increasing temperature a slight decrease of pH measurement can be found (-0.02 pH units from 20--40 degrees C).
Subject(s)
Electrodes , Hydrogen-Ion Concentration , Sterilization , Temperature , Disinfectants , Ethylene Oxide , Evaluation Studies as Topic , FormaldehydeABSTRACT
The ROCHE tissue pH-electrode was tested in acute animal experiments under various metabolic conditions. In anesthetized dogs an electrode was placed in the subcutaneous tissue of the scalp, neck, and axilla. Simultaneous with the continuous measurement of tissue pH, the overall acid-base balance of the animal was measured discontinuously at 5-min intervals by means of indwelling arterial and venous catheters. Various forms of acidosis and hypoxia were produced in the experimental animal and the sensitivity of the electrodes in relation to their site was tested. A high correlation between the continuously measured tissue pH values and the corresponding arterial and venous actual blood pH values were found in the physiologic pH range. With acute changes of acid-base balance no correlation could be found in the acidotic range.
Subject(s)
Acid-Base Imbalance/metabolism , Electrodes , Hydrogen-Ion Concentration , Animals , Arteries , Dogs , Evaluation Studies as Topic , Hydrogen/blood , VeinsABSTRACT
Using this tool the application of the pH electrode is nearly as easy as the attachment of a common ECG-scalp-electrode [3]. Visual control and lithotomy position is not necessary any more. The different tools are adapted to each other so that incision place and the tip of the pH electrode are automatically centered perpendicularly. The first results by using this tool promise to be successful. Time of application is short, the maintenance of the pH electrode is good and the application for the patient no longer disagreeable.
