Neurobehavioral Effects of Local Anesthesia and Fetal Resuscitation

Abstract

The Apgar score has been the traditional and the most frequently used criterion for assessing the well-being of the newborn and the effects of obstetric medication until the recent development of neonatal neurobehavioral assessments. While the Apgar score is an excellent screening test for vital functions during the first minutes of life, the subtle effects of drugs are likely to be overlooked. As a predictor of normal neurologic development, it is a crude tool. Many drugs used in obstetrics that were believed to have no effect on the newborn when evaluated by the Apgar score have been found to have discrete influences when neurobehavioral testing is performed. The Scanlon Early Neonatal Neurobehavioral Scale (ENNS) was the first screening evaluation clinically applicable, easy, rapid, and inexpensive to perform, while having a high inter-observer reliability (>85%). Recently, Amiel-Tison, Barrier and Shnider have devised a scoring system (ABS) to determine adaptive capacity and evaluate neurologic function in full-term infants. The ABS system is quicker than other examinations, puts more emphasis on neonatal tone, and does not use noxious stimuli. Preliminary results indicate that this examination is sensitive and has high inter-observer reliability. However, there are no long-term studies available to determine if the findings on a screening neurobehavioral examination have a significant correlation with later mental and neurologic development of the newborn. Maternal hypotension has been shown to produce neurobehavioral changes and biochemical alterations in the newborn secondary to aortocaval compression by the gravid uterus alone or in conjunction with major regional anesthesia. Short periods of hypotension (