Determination of cord blood gases and pH is recommended in all neonates with low Apgar scores to distinguish metabolic acidosis from hypoxemia or from other causes that might result in low Apgar scores (1). Although the metabolic acidosis found in cord blood is a poor predictor of long-term neurological injury (2), assessment of umbilical cord blood gas is helpful to exclude intrapartum or birth events that cause acidosis and serves as legal evidence against any alleged association with poor outcome (3).Textbook recommendations for postpartum umbilical cord blood sampling include immediate transport of the blood in a heparin-containing syringe placed in a plastic sack containing crushed ice (4). Several studies have previously questioned the utility of this method (5)(6)(7)(8)(9)(10). Sato and Saling (5) evaluated pH values after only 30 min and at every hour up to 7 h in 30 blood samples stored at room temperature and in 30 different samples stored in a refrigerator. They concluded that if fetal blood has to be stored for 50 min, it must be kept refrigerated to inhibit autoxidation. Hilger et al. (6) evaluated the sequential changes in gases and pH in blood taken from the umbilical vein or from a superficial placental vein at 15-min intervals and at room temperature only. They found that as long as blood was taken from the cord vein, the gases and pH were not affected by as long as 1 h delay in sampling. Pel and …
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