One of the objective tools used in medicine and litigation to determine whether a brain injury occurred around birth is umbilical cord blood gas lab work.
When a baby is delivered, the obstetrician or nurse clamp the umbilical cord. This cuts off circulation from the mom and placenta. Collecting an immediate sample of blood from the clamped umbilical cord provides insights about the baby’s metabolic status at the time of delivery.
The umbilical cord contains the umbilical vein and umbilical artery. Veins carry oxygen-rich blood. In the case of the umbilical vein, it transports oxygenated blood from the placenta to the baby. Arteries carry away carbon dioxide. The umbilical artery transports carbon dioxide waste product from the baby back to the placenta.
Whether a blood sample is obtained from the umbilical vein or artery, a laboratory can perform blood gas analysis to determine its content of oxygen or carbon dioxide.
Because blood levels of carbon dioxide are a better predictor of the baby’s well-being— abnormally high levels of carbon dioxide are a significant predictor of neonatal encephalopathy or brain injury—than oxygen levels. Hematologists (physician experts on blood-related conditions) and other specialists prefer blood gas analysis from the umbilical artery, rather the umbilical vein. Sometimes, though, the sample is taken from the larger umbilical vein that easier to access.
Any type of umbilical blood gas analysis documented in the medical record is important evidence to be studied in a medical malpractice claim by appropriate experts. Hematologists are frequently able to estimate the timing of the hypoxic-ischemic insult (and injury caused by inadequate oxygenation to the unborn baby) using cord blood gas data.
The most significant data in cord blood gas studies include the pH and base deficit.
A pH level measures whether the blood is acidic or basic. Generally, a pH of 7.0 is neutral, less than 7.0 is acidic, and greater than 7.0 is basic. A normal blood gas pH is about 7.28 (arterial sample) or 7.29 (venous sample).
The base deficit is a calculation from the pH and carbon dioxide level (more technically the partial pressure of carbon dioxide, abbreviated pCO2). Hematologists and neonatologist consider a base deficit of 12 mmol/L or greater to be consistent with metabolic acidosis. This is a concerning medical condition that poses an increased risk that the baby will have serious problems ranging from death to multiorgan failure and brain damage.
Some birth-related brain injuries are unavoidable, but many others are caused by medical malpractice. When there is suspicion of a birth-related injury in Texas, parents should contact a top-rated experienced Houston, Texas medical malpractice lawyer for help in evaluating the potential case.
