Inside Look at Umbilical Cord Blood Gas Testing
As a baby develops in the womb, they receive oxygen through the placenta, a key feature during pregnancy that transfers vital resources to the growing life. The umbilical cord connects the fetus to the placenta and receives oxygen (and nutrition) through the cord’s blood vessels. Essentially, the umbilical arteries are vital channels used for keeping the baby alive. Inside of the umbilical cord are blood vessels that carry the fetus’s arterial cord blood to and from the placenta for oxygen exchange. The arterial cord blood contains waste-filled, deoxygenated blood that the baby transfers to the placenta and exchanges for the mother’s oxygenated blood. Due to its importance in oxygen delivery, umbilical cord blood gas sampling and analysis can be profoundly illustrative and useful after a baby is born.
Purpose of Blood Gas Testing
After birth, doctors take a small blood sample from the umbilical cord to analyze the newborn’s condition, including oxygen levels. The analysis may also reveal any medical issues and possible birth injuries and conditions. Doctors test a newborn’s blood gas to identify health concerns like oxygen deprivation during labor and delivery. Umbilical cord blood gas analysis evaluates several important measurements to provide an overall picture of the baby’s metabolic environment at the point of delivery.
The blood gas test can reveal several conditions, such as fetal distress during labor and delivery. When the analysis indicates that the fetus may have suffered oxygen deprivation, this is known as fetal hypoxia. In some cases, total oxygen deprivation may have occurred, which is referred to as perinatal asphyxia. Either of these situations can lead to severe brain damage and other complications. Oxygen deprivation occurs temporarily during contractions, but prolonged oxygen deprivation can lead to serious harm, including conditions resulting from neurological damage, such as cerebral palsy, seizures, developmental delays, cognitive impairments, and hypoxic-ischemic encephalopathy (HIE).
Key Elements of Umbilical Cord Blood Gases for Assessment
Blood gas testing gauges pH (particularly the level of acidity in the baby’s blood), the base excess or base deficit, the partial pressure of oxygen, and the partial pressure of carbon dioxide. By measuring these components, a healthcare provider can assess whether the baby suffered oxygen deprivation in utero.
Indicator 1: pH
First and foremost, pH testing detects the acid and alkaline levels in the blood. Ideally, the two are balanced. A low number means the blood is too acidic, and a high number means it is too basic. Abnormal pH readings, one of the key components found in the blood gas analysis, may indicate that the baby endured hypoxia. Too much acid could indicate dangerous health conditions, including breathing problems.
Indicator 2: Base Excess/Deficit
The base excess (BE) measures how much base or acid needs to be added to create a pH balance. If there is a deficit in base in the arterial cord blood, this is correlated with a reduction in pH levels, indicating higher acidity in the blood. A reduced base excess (BE), or higher base deficit (BD), means there is a greater likelihood of the baby suffering from lack of oxygen. Too much base or alkaline can cause rapid breathing or hyperventilation, among more debilitating symptoms like vomiting and dizziness.
Indicator 3: Partial Pressure of Oxygen & Carbon Dioxide
The aim of a partial pressure of oxygen (PO2) test is to measure the blood oxygen pressure to see how well oxygen distributes in the bloodstream from the lungs to the rest of the body. The partial pressure of carbon dioxide (PCO2) test measures the amount and removal of CO2 in and out of the body. Both of these values indicate whether or not the baby’s respiratory function is normal.
All of this important information comes from the umbilical cord blood gas test. After a baby’s birth, doctors clamp the umbilical cord in two places, inserting a needle between the clamps to draw a sample of the umbilical cord blood. The sample is then sent to a lab for analysis.
Analyzing Cord Blood Gas Test Results to Identify Abnormalities
Doctors look for abnormalities in the numbers. Normal test results for pH ranges in arterial blood samples are between 7.18 and 7.38 for a full-term baby, indicating the blood has a balance between base and acid. Normal PO2 readings are 17-27 millimeters of mercury (mmHg), which means the oxygen blood pressure is not too low. Oxygen deprivation is a sign of a health concern. The expected range for the PCO2 is 32.2 to 65.8 mmHg, and the base excess (BE) is +/-0-8 millimoles per Liter (mmol/L).
Low oxygen levels in the PO2 test, blood pH below 7.0, and BE below -12.0 may indicate that the baby experienced fetal hypoxia, which causes acidosis, a condition noted by high acid content in the blood. Hypoxia and acidosis can cause brain damage, which worsens when the source of the hypoxia is not treated early enough. Doctors should monitor, discover, and immediately take action to alleviate fetal hypoxia during labor and birth.
Abnormal test numbers may indicate cord blood metabolic acidosis and hypoxic-ischemic encephalopathy (HIE). The umbilical cord arterial blood analysis may show evidence of HIE from oxygen deprivation. Low pH levels may prompt HIE treatment, which includes hypothermia to avoid brain damage. Low pH also indicates cord blood metabolic acidosis, high levels of acids in the blood when a fetus suffers hypoxia and resulting acidosis. Brain and neurological damage are risks for both conditions.
Potential Causes of Issues with Cord Blood Gas Measurements
When a blood gas test shows abnormal pH or BE readings, the likelihood of worse results in a second test is high. Babies born with poor pH and oxygen readings typically suffered fetal distress in utero. They need immediate treatment to help resuscitate or otherwise assist respiration, as is routinely performed as standard practice. A delay in treatment worsens low oxygen and base levels. Additionally, arterial blood sampling delays or delays in reading the test results can skew cord blood gas values. A blood sample should be drawn within 60 minutes of a clamped cord and 20 minutes from an unclamped cord. Thus, cord clamping should occur promptly to ensure a reliable reading. The most accurate results come from an unclamped cord immediately after birth.
However, results may also fluctuate depending on the birth. A breech or other abnormal presentation of the baby in a vaginal birth may prolong delivery and affect the cord blood gas numbers. Additionally, a vaginal birth will reflect lower oxygen levels due to uterine contractions that stress the fetus compared to a cesarean birth. Finally, umbilical cord problems, including blood clots, can distort blood gas values.
When Should Umbilical Cord Blood Tests be Used?
The American College of Obstetricians and Gynecologists (ACOG) recommends umbilical cord blood gas tests for birth complications involving the mother’s health, mode of delivery, or fetal health. Thus, emergency C-sections, abnormal fetal heart rates, maternal thyroid disease or fever, fetal growth restriction, multiple fetuses, and low APGAR scores may trigger a blood gas test.
However, other obstetrical societies and research indicate that such tests benefit all newborns. Recording cord blood gas test values can help treat newborn complications and improve test result accuracy when physicians routinely test. It would also reduce the delay variables and timing when it becomes a routine practice.
Significance of Blood Gas Testing in Medical Malpractice Cases
Testing umbilical cord blood for oxygen, CO2, and pH balance in newborns is a good idea for many reasons, but when the medical team is negligent, the tests can be particularly helpful in proving a medical malpractice claim against those whose negligence caused harm. Signs of medical malpractice may be evident when complications arise during pregnancy and birth that should have been anticipated or treated. For example, the healthcare team should be prepared for potential problems with older pregnant women or those with a history of pregnancy health conditions, such as gestational diabetes or preeclampsia.
When birth complications occur, the treating physician should order blood gas tests to inform their treatment plan and prevent further injury to the baby from fetal distress and hypoxia that may lead to HIE, among other conditions that require quick action. Even after the baby is born, a medical team must be extra vigilant when they detect fetal distress, initiating necessary steps such as hypothermia treatment and breathing assistance. They must also be keenly aware of warning signs of possible medical issues, as well as observing and taking timely action to treat jaundice or other potentially harmful conditions.
Medical malpractice may occur when doctors fail to diagnose and treat conditions leading to fetal distress and oxygen deprivation, administer tests that would ordinarily detect harmful conditions in the fetus or newborn, monitor conditions to prepare for emergency actions, such as neonatal resuscitation, or treat birth injuries quickly.
Our Birth Injury Team May Use Blood Gas Test Results when Building a Solid Claim
When you know your pregnancy and delivery had complications, and your medical care team responded late or not at all, you probably experience the whole spectrum of emotions from shock, disappointment, outrage, and sadness. You entrusted your baby’s life with trusted medical providers who let you down. When unsure where to turn for legal guidance, our birth injury attorneys can help. Connect with us today to discuss how we can assist with asserting your legal rights to compensation, possibly using your child’s umbilical cord blood gas test results when building the most compelling claim. We will compassionately listen to your experience and offer comfort and advice as to what we can do to hold those responsible accountable so that you and your baby can obtain the necessary financial support for a lifetime.
With our extensive experience and personalized approach, we take extreme care when handling your case, from the initial free consultation to litigating your case at trial. Our team investigates and verifies the validity of your birth injury claim, gathering all of the relevant information, witnesses, records, and evidence to ensure that you are in the best possible position for success. Our attorneys not only use our skills and knowledge to provide a rock-solid foundation when undergoing negotiations for a settlement or arguing your case in court, but we also do the heavy lifting to make sure that your family and your child receive all of the compensation for their past, present, and long-term needs. Your emotional suffering is not without recompense either when you have our birth injury legal team on your side. Call 866-708-8617 to learn more.
