From Big Medical Encyclopedia

GISTEROGRAF (grech, hystera a uterus + grapho to write, represent; synonym: gisterodinamograf, gisterokimograf, tokodinamograf, tonograf) — devices for measurement and registration of the functional indicators characterizing sokratitelny activity of a uterus — frequencies, durations, intensity and coordination of pains at childbirth. Apply in a wedge, practice for the purpose of definition of tactics of conducting childbirth. About intensity and duration of labor pains judge by the curve which is written down by G. — amplitude of teeth, their frequency and size of an interval between them. At uncomplicated patrimonial activity the wave of reductions begins in an upper part of a uterus and extends towards the lower segment (the descending gradient), and reductions of an upper part are more long and have big amplitude. The weakening of patrimonial activity leading to increase in a duration of delivery and other complications is characterized by proportional reduction of reductions in both departments of a uterus. At the disturbance of sokratitelny activity of a uterus (distribution of a wave of reductions from a lower part in upper, alternation of pains, various on amplitude) menacing with delay in childbirth and various complications of mother and to the child, stimulation of patrimonial activity can be made only after holding the relevant activities (administration of hormones, antispasmodics, analgetics, carrying out an electroanalgesia).

Studying of sokratitelny activity of a uterus began at the end of 19 century. In 1870 for this purpose used the device consisting of a spring and the piston, registering reductions of a uterus on tension of a bag of waters. In 1872 Schatz (Ch. F. Schatz) applied a tokodinamograf. In 1896 Schäffer (O. of Schoffer) for registration of frequency and duration of pains offered G. with the sensors installed on a stomach of the woman in labor.

Fig. 1. Two-channel gisterograf: 1 — the sensors installed on a stomach investigated; 2 — a belt for fastening of sensors; 3 — a tape for record gisterogramm; 4 — a gisterograf.
Fig. 2. The scheme of the device providing the control force of pressing of the sensor of a gisterograf: 1 — a nut; 2 — the sensor; 3 — the case; 4 — a belt.

There are devices for registration and measurement of mechanical indicators of a functional condition of a uterus (elasticity of muscles, change of volume and curvature of a stomach, intrauterine pressure, etc.) and devices for registration elektrofiziol. indicators (the biopotentials and electric resistance of fabrics changing at reduction of a uterus). The dvukhkanapny G. developed by All-Union research institute of medical devices (fig. 1) belongs to devices of the first type. For measurement elektrofiziol, indicators of a uterus apply reograf (see. Reografiya ) and devices for registration of biopotentials (see. Analyzers of biopotentials ).

On a way of removal of signals distinguish devices for an outside gisterografiya (sensors establish on a stomach) and for internal (sensors enter into a cavity of the uterus). For registration elektrofiziol, indicators as sensors apply electrodes. For an internal biotelemetric gisterografiya use the sensors executed in the form of radio telemetric capsules like an endoradiosonde with autonomous food. Change of intrauterine pressure causes change of the radio signal given by the capsule which is accepted and registered the special priyemnoregistriruyushchy device (see. Endoradiozondirovaniye ).

An important condition of obtaining comparable information is stability of sensitivity of measuring channels or existence of the device for calibration. In mechanical G., besides, there has to be a device providing the control initial force of pressing of sensors (fig. 2).

For the purpose of obtaining more complete information about patrimonial activity and a condition of mother and child in a complex with G. apply polygraph (see), electrocardiographs (see. Elektrokardiografiya ), phonocardiographs (see. Fonokardiografiya ), electroencephalographs (see. Elektroentsefalografiya ).

Bibliography Persianinov L. S., Zheleznov B. And, ibogoyavlensky N. V. Fiziologiya and pathology of sokratitelny activity of a uterus, page 196, M., 1975, bibliogr.; P r about N and N V. F. Pribor for measurement of sokratitelny activity of a uterus, Honey, the equipment, KV 4, page 16, 1973, bibliogr.

V. F. Pronin, E. M. Kastrubin.