MEASUREMENT OF END TIDAL CARBON MONOXIDE & BILIRUBIN LEVELS (ETCO)

高胆红素血症一直是新生儿科医生和儿科医生共同关注的问题。在美国，正常自然分娩的妇女将在新生儿出生36至48小时后出院。通常情况下，父母直到婴儿出生第四天才会发现黄疸，而缺乏经验的母亲甚至可能错过高胆红素血症的第一个症状。一个昏昏欲睡的黄褐症儿童不起床喂食，因此由于缺乏液体摄入而变得更有黄褐症，这种恶性循环就顺理成章了。在婴儿出院之前，了解新生儿是否会出现需要光疗法的程度，这将是非常有益的。这将省去父母许多痛苦(重新入院接受光疗)，给儿科医生另一个工具来决定何时将婴儿带回进行后续治疗，并将为我们的医疗系统节省一大笔钱。这项研究中使用的呼吸分析仪利用婴儿出生24至36小时时呼吸中一氧化碳的产生。由于呼气末呼气中的一氧化碳(ETCO)与儿童的血红蛋白分解有关，它可以估计随后的胆红素产生。婴儿呼出的空气由CO-Stat END潮汐呼吸分析仪进行分析，只需要被动呼吸1.5分钟。在婴儿的鼻孔处放置了一个特殊的采样器来分析呼吸。为了确保孩子在测试时没有黄褐症(记住，它应该是为了预测高胆红素血症，而不是说明孩子的黄疸)，新生儿筛查测试在产后24至36小时测量血清总胆红素。在出生后96小时(生命的第4天)，提取另一种胆红素，以将ETCO结果与儿童黄疸联系起来。如果结果低于标准小时胆红素正常值的第45个百分位数或高于第95个百分位数，孩子就会退出研究。否则，婴儿将在接下来的24到48小时内接受黄疸监测，如果需要，还会接受光疗。ETCO的结果最终将识别出高胆红素血症的高危新生儿，并使痛苦的血液样本在未来淘汰血清总胆红素。其目标是在出院前建立一项适用于托儿所所有健康婴儿的常规新生儿筛查测试。

Hyperbilirubinemia has been a concern to Neonatologists and Pediatricians alike. In the United States women who have had a normal spontaeous delivery will be discharged with their newborn 36 to 48 hours after birth. Usually the jaundice doesn't become obvious to the parents until day four of baby's life and an inexperienced mother might even miss the first symptoms of hyperbilirubinemia. The vicious cycle of a sleepy jaundiced child who doesn't wake up for its feeds and therefore gets even more jaundiced due to lack of fluid intake takes its course. It would be very beneficial to know whether a newborn will get jaundiced to the degree that it requires phototherapy before the baby gets discharged from the hospital. This would spare the parents a lot of distress (readmission of child for phototherapy), give the pediatrician another tool to decide when to bring the baby back for follow-up and would save our health system a lot of money. The breath analyzer used in this study takes advantage of the carbon monoxide production in the infant's breath at 24 to 36 hours of life. As the CO in the endtidal breath (ETCO) is realted to the child's hemoglobin breakdown, it can estimate the subsequent bilirubin production. The baby's exhaled air is analyzed by a CO-Stat End Tidal Breath Analyzer and requires passive breathing for only 1 1/2 minutes. A special sampler is placed at the nostril of the baby to analyze the breath. To make sure that the child wasn't jaundiced at the time of the test (remember it is supposed to predict hyperbilirubinemia and not state the child's jaundice) a serum total bilirubin is measured at 24 to 36 hours postdelivery with the newborn screening test. At 96 hours (4th day of life) another bilirubin is drawn to relate the ETCO result to the child's jaundice. If the results fall below the 45th percentile or above the 95th of a standard hour bilirubin nomogram, the child exits the study. Otherwise the baby is monitored over the next 24 to 48 hours regarding its jaundice and if needed, placed under phototherapy. The ETCO result will ultimately identify neonates who are at high risk of developing hyperbilirubinemia and make painful blood sampling for a serum total bilirubin obsolete in the future. The goal is to establish a routine newborn screening test applied to all well babies in the nursery before discharge.