[Significance of partial pressure and pH value of umbilical venous blood and umbilical arterial blood in the diagnosis of the condition of the newborn infant following early or late cord clamping].

The condition of the newborn at birth is documented by the Apgar score and by the blood gas analysis of the umbilical arterial blood. The question arises whether the estimations are still valid if the cord is clamped late. The investigations have been performed on 20 newborn at term: 10 babies were clamped late and 10 immediately after birth. The blood was analysed from both vessels near the placenta and the child. The pH, base excess, PCO2 and PO2 showed in both groups the expected gradients along the umbilical circulation. There was also no difference of these parameters between the two groups of early (EC) and late (LC) cord clamping: pH LC 7,26 (SD 0.05), EC 7.32 (SD 0,04)), base excess (LC - 7.7 meq/1 (SD 2.3); EC -5.2 meq/1 (SD 5.0)), PCO2 (LC 52 mmHg (SD 7); EC 44 mmHg (SD 6)) and P02 (LC 18 mmHg (SD 3); EC 17 mmHg (SD 3)). From these observations it may be concluded that the start of ventilation does not influence the blood gases in the umbilical vessels of the late clamped newborn. It may be caused by the sudden ceasing of the umbilical circulation at birth.