CTG (Cardiotocography) Information PDF
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This document provides a detailed overview of cardiotocography (CTG), a procedure used to monitor fetal heart rate and uterine activity during pregnancy. It explains the procedure, normal and abnormal patterns, and the features analysed to assess fetal wellbeing. The document also discusses the computerized interpretation of CTG.
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CTG د.اﯾﻤﺎن ﻧﺒﯿّــﻞ ﻣﺤﻤﺪ Basal line CTG Acceleration Deceleration Variability This is no...
CTG د.اﯾﻤﺎن ﻧﺒﯿّــﻞ ﻣﺤﻤﺪ Basal line CTG Acceleration Deceleration Variability This is normal CTG Basal line is 140 , Normal variability , with acceleration, and no deceleration Antenatal, normal tachycardia Reduced variability bradycardia Variable decelerations Variable deceleration Late deceleration, no variability Abnormal CTG Late, prolonged decelerations. Loss variability The cardiotocograph (CTG) — continuous tracing of the fetal heart rate used to assess fetal wellbeing, together with an assessment of uterine activity. — sometimes called electronic fetal monitoring (EFM). Procedure : - pregnant woman positioned comfortably in a left lateral or semi-recumbent position to avoid compression of the maternal vena cava. - Two external transducers are placed on the mother’s abdomen, each attached with a belt. - One transducer is a pressure-sensitive contraction tocodynometer (stretch gauge) that measures the pressure required to flatten a section of the abdominal wall. This correlates with the internal uterine pressure and indicates if there is any uterine activity (contractions). - The second transducer uses ultrasound and the Doppler effect to detect motion of the fetal heart, and measures the interval between successive beats, thereby allowing a continuous assessment of fetal heart rate. - Recordings are then made for at least 30 minutes with the output from the CTG machine producing two ‘lines’ traced onto a running piece of paper, one a tracing of fetal heart rate and a second a tracing of uterine activity. - The mother may be given a button to press to record any fetal movements that she has felt. In addition, the CTG machine may record fetal movements detected via the tocodynometer. Features that are reported from a CTG to define normality and identify abnormality and potential concern for fetal wellbeing include the: 1— Baseline rate. 2— Baseline variability. 3— Fetal heart rate Accelerations. 4— Fetal heart rate Decelerations. * From the above descriptions, a normal antepartum fetal CTG can therefore be defined as a baseline of 110–150 bpm, with baseline variability exceeding 10 bpm, and with more than one acceleration being seen in a 20–30 minute tracing. * suspicious CTG must be interpreted within the clinical context. If many antenatal risk factors have already been identified, a suspicious CTG may warrant delivery of the baby, although where no risk factors exist, a repeated investigation later in the day may be more appropriate The computerized cardiotocograph The basis of fetal CTG is pattern recognition, and this leads to differences in interpretation amongst different clinicians. Computerized CTG interpretation packages have been developed. These packages have been shown to be equal (or superior) to human interpretation in differentiating normal from abnormal outcome.