The effect of clamped and unclamped umbilical cord samples on blood gas analysis.

Samples from the unclamped cord alter the acid-base parameters compared to collection from the clamped cord; however, this difference does not appear to be of clinical relevance. Findings could be due to the large sample size, which allowed to achieve a high power and to investigate very small numerical changes between groups, leading to a statistically significant difference in pH and BE between samples even when we could not appreciate any clinical relevant difference of pH or BE between groups. When blood gas analysis is indicated, the priority should be given to the timing of blood collection to allow reliable results, to assess newborns status at birth and intervene when needed.