SCIENTIFIC
Cardiodynamic Profiles of Gravidas with Obesity in Early Gestation
AUTHORS : Jesse Cottrell , MD
William Hayes , MS4 David Jude , MD David Chaffin , MD
Marshall University Joan C . Edwards School of Medicine Department of Obstetrics and Gynecology
INTRODUCTION
Obesity in pregnancy has long been identified as a key contributor to adverse maternal and fetal outcomes . The risk of spontaneous miscarriage , stillbirth , preterm delivery , fetal malformations , gestational diabetes , fetal macrosomia , cesarean section , thromboembolic complications , and hypertensive complications are all increased in pregnant women with obesity when compared to pregnant women with a normal Body Mass Index ( BMI ). 1
Gravid women undergo substantial hemodynamic adaptations throughout the course of pregnancy . To meet the physiologic demands of pregnancy , blood volume , heart rate , stroke volume , cardiac output , vascular resistance , and blood pressure are altered . 2 Under normal circumstances , the gestational period is considered to be a high flow-low resistance state . 3 Pathologic alterations in these hemodynamic adaptations lead to adverse pregnancy outcomes . 3
With the obesity epidemic becoming an ever-increasing issue , noninvasive hemodynamic profiling via impendence cardiography offers the opportunity to further explore how cardiovascular function is influenced by maternal weight . 4 We sought to determine if maternal hemodynamics are altered in early gestation between pregnant patients with obesity compared to those without obesity using non-invasive hemodynamic monitoring .
ABSTRACT
BACKGROUND Obesity is a significant contributor to adverse maternal and perinatal outcomes , increasing the risk of spontaneous miscarriage , stillbirth , preterm delivery , fetal malformations , gestational diabetes , fetal macrosomia , cesarean section , maternal thromboembolic complications , and hypertensive complications . Historical data indicate that nonpregnant individuals with obesity typically have an elevated cardiac output , increase in total and central blood volume , and low peripheral vascular resistance . Studies measuring hemodynamic parameters in pregnant patients with obesity is lacking .
METHODS A retrospective study was conducted in 796 pregnant patients referred to the Maternal Hypertension Center at Cabell Huntington Hospital ; 335 had a Body Mass Index ( BMI ) of < 30kg / m 2 , 171 had a BMI of 30kg / m 2 – 34.9kg / m 2 , 154 had a BMI of 35kg / m 2 – 39.9kg / m 2 , and 136 had a of BMI ≥ 40kg / m 2 .
MATERIALS AND METHODS
A retrospective study was conducted in 796 patients referred to the Maternal Hypertension Center at Cabell Huntington Hospital between 2005 and 2014 . Inclusion criteria were patients who underwent hemodynamic testing that did not meet the criteria or carry the diagnosis of chronic hypertension using the American College of Obstetrics and Gynecology guidelines . 5 Participants were referred for hemodynamic testing due to a history of prior pregnancy complicated by preeclampsia ( n = 174 ), type 2 diabetes mellitus ( n = 172 ), type 1 diabetes mellitus ( n = 10 ), chronic renal failure ( n = 9 ), obesity , or referring physician discretion ( n = 431 ). The mean gestational age at the time of assessment was 16 weeks . Exclusion criteria also included patient ’ s already prescribed blood pressure medications .
Maternal hemodynamic parameters were obtained using non-invasive impedance cardiography ( NICaS , NI Medical USA ,
RESULTS The maternal hemodynamic parameters showed significant differences in systolic blood pressure ( p value <. 01 ), mean arterial pressure ( p value = 0.01 ), cardiac output ( p value < 0.01 ), and systemic vascular resistance ( p value < 0.01 ). There were no significant differences in maternal heart rate ( p value = 0.2093 ) or diastolic blood pressure between groups ( p value = 0.1139 ).
CONCLUSION Non-invasive hemodynamic testing offers the opportunity to further explore pathologic cardiovascular alterations of pregnant patients with obesity . Further research is needed to categorize hemodynamic parameters , with an attempt to explore potential interventions to improve pregnancy outcomes for gravidas with obesity .
Chapel Hill , NC , USA ). The standard protocol at our institution includes that the patient is in a sitting position with feet flat on the floor , blood pressure taken in the right arm with an automatic blood pressure cuff , and sensors placed above the radial artery on each wrist .
Demographic information was extracted from each patient ’ s electronic medical record . The maternal parameters collected were patient age , BMI , and gestational age at the time of assessment . Hemodynamic data was extracted from the OHMS software ( Medical Information Systems Technology , Huntington , WV , USA ). The parameters measured were heart rate , systolic blood pressure , diastolic blood pressure , mean arterial pressure , cardiac output , and systemic vascular resistance . The delivery information collected was as follows : gestational age at the time of delivery , birth weight , birth weight percentile , and Apgar score . The patients were divided into four BMI categories based on the In-
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