Medical Student Research Fellowship for Summer 2012
Mentor: Charles R. Rosenfeld, MD
Department: Pediatrics, Division of Neonatal-Perinatal Medicine
Room number: E3.302C
Mail Code: 9063
Phone number: 83903
Project title: Fetal well-being and the use of α-agonists in the treatment of maternal hypotension during cesarean delivery with regional anesthesia.
Human subjects IRB approved project number (where applicable): STU 122011-013
Animal subjects IRB approved project number (where applicable): NA
Project Type (patient-based research, animal-based research, or basic research; this characterization is only to permit a general classification for grouping similar types of projects) patient-based research
Brief Description of Project:
The proposed study is a two year (January 2010 through December 2011) retrospective chart review of the mother and her neonate delivered at Parkland Memorial Hospital designed to determine in women undergoing cesarean delivery with regional anesthesia the prevalence of maternal hypotension, the need for ephedrine and/or phenylephrine as pressor therapy, and the occurrence and significance of fetal acidosis and compromised well-being due to the use of these pressors. The study is the result of publications by our lab over the past 20yrs and in Jan 2012 (JCEM, AJP) that vascular sensitivity to α-agonists is markedly elevated in the uteroplacental vasculature of women and sheep compared to the systemic vasculature, resulting in decreases in uteroplacental blood flow at nonpressor doses of several α-agonists, including phenylephrine which is a commonly used pressor. Moreover, there are numerous clinical papers suggesting that this is an important issue resulting in a compromised fetus at birth. We estimate there will be ~12,000 births/year at Parkland Memorial Hospital during the study period of which 30% will be delivered by cesarean section (3,600/yr) and ~90% of whom will receive spinal anesthesia (3240/yr). Thus, we will examine ~13,000 charts, (6480 maternal charts and their corresponding newborn charts) in detail (see below). We estimate that ~80% (~5184) of the mothers will have hypotension and may need some form of intervention. There will be 4 study groups of women and their newborns: 1. regional anesthesia, but no hypotension, 2. regional anesthesia and hypotension treated with volume expansion alone, 3. regional anesthesia and hypotension treated with volume expansion and pressor therapy, and 4. regional anesthesia and hypotension not treated. Each group will be assessed for complications before and during delivery and evidence of compromised fetal well-being as evidenced at birth by the presence of fetal acidosis, the need for resuscitation, and/or the need for admission to the Neonatal ICU or the level 2 nursery in the Term Nursery. The initial analysis will include only those neonates delivered in the year 2011 as it is estimated that nearly 3,000 mother-infant pairs will be included. The student will work directly with the fellow in Neonatal-Perinatal Medicine to assess the charts and collect the maternal-infant data, attend lab meetings assessing the data collection and their analyses, participate in the data analyses, and attend the Monday Perinatal Conference at Parkland where high-risk pregnancies and neonates are discussed as well as other clinical conferences related to perinatal medicine.
Previous Research Activities or Publications with Medical Students:
Dr. Rosenfeld has mentored 16 medical students from UT Southwestern and other institutions. They have worked with him on either lab or clinical based research projects. Many have published manuscripts and/or presented research presentations at national or international meetings. Recent students include: