Interpretation of results by Krebs/Fischer
At the end of 1976, W. Fischer proposed a cardiotocogram scoring system, modified in 1978 by N. Krebs. This system is widely used, it includes an assessment of the frequency of the basal rhythm, the amplitude of instantaneous oscillations, the frequency of oscillations, the number of accelerations and decelerations in 30 minutes, the number of fetal movements in 30 minutes. This is a twelve-point system in which a certain number of points is awarded for each indicator. At the end of the study, the system sets a point score, according to which, with a certain degree of probability (75%), one can judge the condition of the fetus.
Criteria for assessing the condition of the fetus according to Krebs:
- from 9 to 12 points – the child's condition is satisfactory, he is healthy and feels quite comfortable;
- from 6 to 8 points - nothing threatens the child's life, but his condition causes concern, since such an indicator may be a sign of hypoxia, initial pathological changes and adverse external influences, it is shown to do CTG more often to monitor the baby in dynamics;
- 5 points or less - the child's condition is threatening, there is a high risk of intrauterine death, stillbirth, neonatal death in the early postpartum period, severe fetal hypoxia. The woman is sent to the hospital, where an urgent diagnosis is carried out, and in most cases everything ends with an emergency caesarean section to save the baby's life.
Fischer scoring table (Krebs modification).
|The indicator determined on CTG||1 point is awarded if:||2 point is awarded if:||3 point is awarded if:|
|Base heart rate||Less than 100 bpm or more than 100 bpm||100-120 bpm or 160-180 bpm||121-159 bpm|
|Expression of slow oscillations||Less than 3 bpm||3 to 5 bpm||From 6 to 25 bpm|
|Number of slow oscillations||Less than 3 during the study period||3 to 6 per study period||More than 6 during the study period|
|Number of accelerations||Not fixed||1 to 4 in half an hour||More than 5 in half an hour|
|Decelerations||Late or variable||Variable or late||Early or not fixed|
|Movements||Not fixed at all||1-2 in half an hour||More than 3 in half an hour|