Use of Cheetah® Non-invasive Cardiac Monitoring System to Guide Discontinuation of Postpartum Magnesium Sulfate in Women With Severe Preeclampsia: A Pilot Randomized Control Trial
Phase: NA
Conditions: Preeclampsia With Severe Features
Sponsor: Ohio State University

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

USE OF CHEETAH® NON-INVASIVE CARDIAC MONITORING SYSTEM TO GUIDE DISCONTINUATION OF 
POSTPARTUM MAGNESIUM SULFATE IN WOMEN WITH SEVERE PREECLAMPSIA: 
A PILOT RANDOMIZED CONTROL TRIAL. 
Investigator Initiated Study 
Investigators: 
OSU MFM and Anesthesia 
Protocol Version: 
 Version 3.0 
Date: 
January 31, 2022 
 Sponsor:
Baxter Healthcare Corporation 
Confidentiality and Proprietary: This document contains confidential information and is intended 
solely for use by specified clinical investigator(s) or regulatory authorities and must not be 
disclosed to any other party. Acceptance of this document constitutes the agreement that no 
unpublished information contained herein will disclosed without prior written approval of Baxter 
and the Ohio State University Wexner Medical Center except that this document may be disclosed 
to appropriate Ethics Committees who will agree to keep it confidential. 
1&7

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

1 
STUDY SYNOPSIS 
Title 
Use of Cheetah® non-invasive cardiac monitoring system to guide 
discontinuation of postpartum magnesium sulfate in women with severe 
preeclampsia: A pilot randomized control trial. 
Objective 
Demonstrate the utility of using improvement in SVR via non-invasive cardiac 
monitor as an indicator for resolution of preeclampsia, and individualize the 
duration of magnesium in the postpartum period for women with preeclampsia 
with severe features. 
Study 
Population 
Pregnant women greater than 18 years of age and 24 0/7 weeks’ gestational 
age admitted to L&D for delivery with preeclampsia with severe features and 
plan to receive magnesium sulfate. 
Study 
Design 
This is a single site pilot randomized, controlled, trial randomizing patients with 
PE with severe features to one of 2 groups: 
x
24 hours of postpartum magnesium sulfate (current arbitrary
standard of care)
x
Using the Cheetah® device to aid in an individualized duration of
magnesium sulfate based on reduction in SVR, up to a maximum
of 24 hours postpartum.
Eligibility 
Subjects enrolled in the RCT must meet all of the inclusion criteria listed below: 
Inclusion Criteria 
x
PE with severe features, diagnosed using the ACOG standard criteria4 
requiring magnesium sulfate
x
Females older than 18 years of age
x
Singleton pregnancy
x
Gestational age greater than 24 0/7 weeks
x
The patient is physically and mentally able to understand the informed
consent and is willing to participate in this study
x
Able to speak English or Spanish
Subjects enrolled in the RCT must not have any of the exclusion criteria listed 
below: 
Exclusion Criteria 
x
Multiple gestation
x
Prisoners
x
Patients with chronic renal insufficiency or epilepsy
x
Known cardiovascular disease
x
Patients with contraindications to magnesium sulfate use (e.g.
myasthenia gravis)

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

x
Patients with eclampsia or HELLP syndrome
x
Contraindications for magnesium sulfate
(In addition to subjects enrolled in the RCT, we propose an optional negative 
control cohort of 25 normotensive healthy women delivering > 37 weeks to 
compare hemodynamics) 
Site 
The Ohio State University Wexner Medical Center 
Sample 
Size 
60 patients with preeclampsia with severe features and plan to receive 
magnesium sulfate. 
(In addition to subjects enrolled in the RCT, we propose an optional negative 
control cohort of 25 normotensive healthy women delivering > 37 weeks to 
compare hemodynamics) 
Study 
Duration 
Estimated duration of study is approximately 1 year. 

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

2 
LIST OF ABBREVIATIONS 
ACOG 
American Congress of Obstetricians and Gynecologists 
BMI 
Body Mass Index 
BP 
Blood Pressure 
CFR 
Code of Federal Regulations 
CI 
Confidence Interval 
CO 
Cardiac Output 
CRF 
Case Report Form 
GCP 
Good Clinical Practice 
HELLP 
Hemolysis, Elevated Liver Enzymes, Low Platelet Count 
HIPAA 
Health Information Portability and Accountability Act 
HR 
Heart Rate 
ICF 
Informed Consent Form 
IDE 
Investigational Device Exemption 
IRB 
Institutional Review Board 
IV 
Intravenous 
LMP 
Last Menstrual Period 
MAP 
Mean Arterial Pressure 
Mg2+ 
Magnesium Ion 
MgSO4 
Magnesium sulfate 
NICU 
Neonatal intensive care unit 
PE 
Preeclampsia 
SAE 
Serious Adverse Event 
SD 
Standard deviation 
SVR 
Systemic Vascular Resistance 

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

3 
BACKGROUND 
3.1 
Pregnancy hemodynamic changes 
Pregnancy is a dynamic process associated with significant physiological changes in the 
cardiovascular system. These changes include an increase in cardiac output (CO), heart rate 
(HR), blood volume expansion, and a decrease in blood pressure (BP) and systemic vascular 
resistance (SVR) during pregnancy1. On the other hand, labor is associated with significant 
hemodynamic changes, including increased CO and BP, and other parameters which are altered 
after administration of neuraxial anesthesia2,3. Additionally, after the delivery of the placenta, there 
is a rapid return of CO and SVR to non-pregnant levels2. 
3.2 
Preeclampsia 
Preeclampsia (PE) is a multisystem disorder affecting up to 
8% of pregnancies and is diagnosed using standard clinical 
and biochemical criteria (Box 1)4. PE with severe features is 
diagnosed with either systolic blood pressure of 160mm Hg 
or more, or diastolic blood pressure of 110mm Hg or more 
on two occasions at least 4 hours apart (unless 
antihypertensive therapy is initiated before this time) and/or 
the presence of end organ injury such as thrombocytopenia, 
liver or renal injury, pulmonary edema, persistent symptoms 
(as defined in box 1) or eclampsia. 
Globally, PE is a leading cause of morbidity and mortality for 
pregnant women. Pregnant women who develop PE are at 
risk of eclampsia, a serious complication defined as new 
onset seizures and/or unexplained coma in the setting of PE, 
stroke, placental abruption, coagulopathy, pulmonary 
edema, acute kidney injury, liver hematoma, intracranial 
bleeding, cardiopulmonary arrest, and death. Moreover, PE 
increases risk of future cardiovascular disease and 
represents a significant economic burden on healthcare 
systems5. Published literature has identified striking 
differences in the maternal hemodynamic profiles between 
normotensive pregnancies and those complicated by PE. PE 
is associated with a significantly higher BP and SVR with 
lower HR, stroke volume, and CO6. 
Box 1: Criteria for Diagnosis of PE 
Systolic blood pressure of 140mm Hg or 
more, or diastolic blood pressure of 90mm 
Hg or more on two occasions at least 4 
hours apart (unless antihypertensive 
therapy is initiated before this time) 
AND one of 
x Proteinuria 
(urine 
protein/creatinine
ratio >0.3, 24-hour urine protein
PJ or  proteinuria on urine
dipstick)
x Thrombocytopenia (platelet count less
that 100,000 x 109/L)
x Impaired liver function as indicated by
abnormally 
elevated 
blood
concentrations of liver enzymes (to
twice 
the 
upper 
limit 
of 
normal
concentration), and severe persistent
right upper quadrant or epigastric pain
unresponsive to medication and not
accounted for by alternative diagnoses
x Renal insufficiency (serum creatinine
concentration more than 1.1 mg/dL or a
doubling of the serum creatinine
concentration in the absence of other
renal disease
x Pulmonary edema
x New-onset headache unresponsive to
medication and not accounted for by
alternative diagnoses
x Visual disturbances
Women with PE also have higher levels of placental-derived anti-angiogenic proteins and 
significantly lower levels of pro-angiogenic proteins, when compared with healthy pregnant 
women7. The increased SVR noted in pregnancies complicated by PE have been associated with 
abnormal plasma levels of angiogenic proteins7,8. 
The cure for PE has remained the same for several decades: delivery of the fetus and placenta. 
Immediately after birth, there is resolution of many of the clinical symptoms of PE, including a 
decrease or normalization in BP, improvement in urine output, and improvement of symptoms of 
end organ damage, along with reduction in stroke volume, CO, mean arterial pressure (MAP), 
and SVR6. 
In the U.S., parenteral magnesium sulfate (MgSO4) is routinely given to pregnant women for the 
prevention of eclampsia in patients with PE, especially those with severe features, as multiple 

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

studies and meta-analyses demonstrated its superiority compared with other agents9. However, 
despite the clear and therapeutic importance of MgSO4 in pregnancy, there are limited data on 
its optimal dosing. The MgSO4 dosing regimen currently used is based on a protocol developed 
more than 30 years ago and does not take into account patient characteristics. In addition, the 
“therapeutic dose” of MgSO4 has been determined empirically and is based upon historic 
dosages found to be typically tolerable and effective. In clinical practice, dosing is based on a 
standard protocol, irrespective of patient’s characteristics. Typically, it is administered by an 
intravenous (IV) infusion with a loading dose of 4 to 6 grams over 15-30 minutes, followed by 2 
g/h as a continuous IV infusion up to 24 hours postpartum9. The use of MgSO4 requires a higher 
level of care with frequent blood pressure monitoring, close urine output monitoring, and frequent 
examinations for signs of magnesium toxicity (such as loss of deep tendon reflexes and 
respiratory depression)10. It is estimated that women receiving MgSO4 are almost 5 times more 
likely to experience adverse events compared with those receiving no or other treatments. This 
is associated with significant healthcare costs11 and patients dissatisfaction. 
Moreover, there is no consensus in the published trials regarding the optimal dose to use (both 
loading and maintenance), or the duration of therapy (especially in the postpartum period) 4. 
Multiple recent studies have questioned the utility of the use of magnesium sulfate for 24 hours 
postpartum and suggest no increased risk of eclampsia or maternal morbidity with use of shorter 
durations of use (such as 6 hours or 12 hours)12–14. However, most studies have no clear definition 
of a clinical parameter that defines the recovery phase from severe PE. One of several parameters 
that has been described as an indicator of clinical improvement from PE is the onset of diuresis15. 
This is believed to be a signal for reversal of increased SVR (vasoconstriction), and thus resolution 
of the disease. Historically, it was only possible to measure SVR with an invasive monitor such 
as a pulmonary artery catheter. The potential complications with these measurements outweighed 
the risk of benefit. Novel techniques including thoracic bioreactance, enable minimally invasive 
measurements of SVR and have been validated in the obstetric population.16 
3.3 
SVR as a measure of disease resolution 
Although, the use of MgSO4 is to prevent eclamptic seizures, the rarity of these events in the U.S. 
severely diminishes the feasibility of any research study with seizure mitigation as a primary 
outcome. Therefore, a hemodynamic surrogate end point (SVR), based on the key 
mechanism of action of MgSO4 as a vasodilator for eclampsia prevention, was selected. 
We are proposing to measure improvement in SVR using a novel, non-invasive, and well- 
validated hemodynamics monitoring system, as a criterion to discontinue MgSO4, in the 
postpartum period. Although the exact etiology of eclampsia is still unknown, it is believed that 
cerebral vasospasm plays an essential role. It is hypothesized that in the setting of PE, and as 
blood pressure increases out of the normal range, cerebral resistance increases to limit cerebral 
perfusion. Ultimately, with increasing blood pressure and cerebral perfusion pressure, 
autoregulation is lost, which in the setting of endothelial dysfunction leads to vasogenic edema, 
overperfusion injury, and eclampsia. Magnesium is a calcium antagonist and can act on many 
calcium channels in the vascular smooth muscle. This leads to decrease in intracellular [Mg2+], 
inactivation of calmodulin-dependent myosin light chain kinase activity and reduced vascular tone, 
which subsequently leads to vascular (arterial) relaxation, and dilatation. Since vascular 
resistance in inversely related to the 4th power of blood vessel radius, effect of MgSO4 on 
vasodilation has the most significant impact on peripheral and cerebral vascular resistance. This 
vasodilatory effect of MgSO4, which we can detect peripherally, using Cheetah non-invasive 
cardiac monitoring, severs as a rationale for this study. 

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

Therefore, we sought to demonstrate the utility of using improvement in SVR via non- 
invasive cardiac monitor as an indicator for resolution of PE, and individualize the duration 
of magnesium in the postpartum period for women with PE with severe features. 
4 
Hypothesis 
We hypothesize that the use of the Cheetah® non-invasive cardiac monitor to individually 
determine the duration of magnesium sulfate postpartum (guided by timing of reduction in SVR) 
will result in shorter duration of MgSO4 infusion, compared with the traditional preset time point 
of 24hr postpartum, with no increase in maternal morbidity. 
5 
STUDY DESIGN 
5.1 
Type of Study 
This is a single site pilot randomized, controlled, trial randomizing patients with PE with severe 
features to one of 2 groups: 
x
24 hours of postpartum magnesium sulfate (current arbitrary standard of care)
x
Using the Cheetah® device to aid in an individualized duration of magnesium sulfate
based on reduction in SVR, up to a maximum of 24 hours postpartum.
A 30% reduction in SVR (maintained for 1 hour) from the time of delivery will be used as an 
indicator for resolution of PE and as the cutoff for discontinuation of magnesium sulfate. This 
SVR reduction is previously described in normal pregnancy within 1 hour postpartum2 and 
similar reduction in SVR in pregnancies complicated by severe PE, from after delivery to 24- 
36hrs postpartum6. 
In addition to subjects enrolled in the RCT, we propose an optional negative control 
cohort of 25 normotensive healthy women delivering > 37 weeks to compare 
hemodynamics. 
5.2 
Study Population 
Patients who meet all the inclusion and none of the exclusion criteria will be enrolled in the RCT 
part of the study. 
Inclusion Criteria 
x
PE with severe features, diagnosed using the ACOG standard criteria4 requiring
magnesium sulfate
x
Females older than 18 years of age
x
Singleton pregnancy
x
Gestational age greater than 24 0/7 weeks
x
The patient is physically and mentally able to understand the informed consent and is
willing to participate in this study
x
Able to speak English or Spanish

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

Exclusion Criteria 
x
Multiple gestation
x
Prisoners
x
Patients with chronic renal insufficiency or epilepsy
x
Known cardiovascular disease
x
Patients with contraindications to magnesium sulfate use (e.g. myasthenia gravis)
x
Patients with eclampsia or HELLP syndrome
x
Contraindications for magnesium sulfate
5.3 
Study Outcomes 
Primary Outcome: 
Duration of magnesium sulfate use in the postpartum period defined as the duration in hours 
between delivery and discontinuation of magnesium sulfate. 
Secondary safety Outcome: 
Composite of eclampsia, pulmonary edema, renal insufficiency/acute kidney injury, venous 
thromboembolism, peripartum cardiomyopathy, ICU admission, or maternal death. 
Secondary Maternal clinical Outcomes 
Maternal secondary outcomes 
x
Need for or up-titration of antihypertensive agents postpartum for severe hypertension
x
Hospital readmission up to 4 weeks postpartum
x
Changes in arterial blood pressure in the peripartumpartum period
x
Changes in cardiac output during the peripartum period
x
Changes in heart rate in the peripartum period
x
Need to restart magnesium sulfate
x
Urine output, and the onset of diuresis defined as UOP >0.5ml/hour for 2 consecutive
hours
x
Preeclampsia symptoms resolution
x
Correlation between magnesium levels and changes patient hemodynamics
x
Anesthetic type
x
Length of stay in Labor and delivery
x
Total hospital length of stay
x
Hospital cost
x
Patient satisfaction

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

x
Time to start regular diet and ambulation
x
Maternal non-invasive cardiac parameters pre- and post-neuraxial anesthesia, pre- and
post starting magnesium sulfate, with pushing or during cesarean delivery, and after the
use of different anti-hypertensives (e.g. labetalol, nifedipine, hydralazine) for emergent
therapy for severe hypertension
x
Postpartum hemorrhage or blood transfusion
x
Postpartum resources utilization including ER/triage visits, scheduled or non-scheduled
clinic visits
Neonatal secondary outcomes 
x
Fetal or neonatal death
x
Intubation, continuous positive airway pressure (CPAP) or high-flow nasal cannula
(HFNC) for ventilation or cardiopulmonary resuscitation within first 72 hours
x
Composite of either neonatal encephalopathy as defined by the NICHD Neonatal
Research Network criteria, seizures, or intracranial hemorrhage (intraventricular
hemorrhage, subgaleal hematoma, subdural hematoma, or subarachnoid hematoma)
x
Hyperbilirubinemia requiring phototherapy or exchange transfusion
x
Hypoglycemia (glucose < 35 mg/dl) requiring IV therapy
x
NICU admission and length of stay in NICU
5.4 
Study Procedures 
Patients with PE with severe features admitted for delivery, will be screened for eligibility. Those 
who meet all the inclusion criteria and none of the exclusion criteria will be approached for 
participation. Subjects shall sign an informed consent form (ICF) approved by our site’s 
Institutional Review Board (IRB), which includes Health Information Portability and Accountability 
Act (HIPAA) authorization information. The informed consent process shall be completed by the 
PI or designee prior to initiation of the study procedures. The original signed and dated informed 
consent form is to remain in the subject’s research records; one copy is provided to the subject; 
and per site requirements, once copy placed in the medical record. 
If a patient expressed interest and signs the ICF, she would be enrolled in the study and 
randomized to one of the two arms. Randomization will occur as soon as decision to deliver is 
made, and before start of mgSO4. Those assigned to the Cheetah arm, will have the device 
placed ASAP after randomization and before start of magnesium sulfate, in order to obtain 
baseline hemodynamic parameters. 
In addition to subjects enrolled in the RCT, we propose an optional negative control cohort of 25 
normotensive healthy women delivering > 37 weeks to compare hemodynamics. 
Once informed consent is obtained, baseline procedures including collection of demographic, 
medical and obstetric histories, vitals (weight, height, and blood pressure), concomitant 
medications (con meds), and other pertinent clinical information will be obtained. Intrapartum and 
postpartum outcomes, including receipt of anesthesia and anti-hypertensive medications will be 
collected. In addition to collecting non-invasive cardiac parameters, hourly urine output and serial 
magnesium sulfate levels will be measured. Delivery outcomes (maternal and neonatal clinical 
information) will be collected on all subjects enrolled in the study. 

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

5.5 
Data Collection 
Case Report Forms (CRFs) will be completed by research staff through patient interview and 
medical chart abstraction. Clinical data, including subject demographics and information on the 
current and previous pregnancies, The PI or designated staff reviews CRFs and database entry 
for accuracy. 
Information obtained directly (patient interview) or indirectly (chart abstraction) is specifically for 
research purposes and obtained by trained members of the site’s research staff. No subject 
names or other identifiers will be recorded on CRFs. Paper CRFs will be utilized with data written 
legibly, using black pen. Source documents will be kept as originals in the site’s specific research 
chart. All entries will be signed and dated. Corrections will be made by making a single strike 
through on the prior entry with correction to the side to include date and in the initials of the 
research staff. Research staff will undergo an initiation training session to learn standard 
procedures for data entry. 
5.6 
Subject’s Study Duration 
In addition to the immediate delivery and postpartum data collection, postpartum data including 
any readmissions, ER/triage visits, scheduled or non-scheduled clinic visits will be recorded up to 
4 weeks postpartum. If patient did not present for follow up, a phone call will be made to collect 
these data. Therefore, participation in this study ends after the last contact with the patient with a 
maximum potential study duration would be 4 weeks. 
5.7 
Subject Withdrawal 
Subjects may withdraw from the study at any time without penalty or repercussion and for any 
reason without prejudice to their future medical care. 
5.8 
Regulatory Compliance 
This study will be conducted in accordance with this protocol and the applicable requirements 
outlined in ICH E6 Good Clinical Practices and Title 21 CFR. The study will also be conducted in 
conformance with the Declaration of Helsinki and local laws and regulations. 
This study will be exempt from the IDE requirements under Section 812.2(c)(3) because the 
device is (i) noninvasive; (ii) does not require any invasive sampling procedures that present 
significant risk [per 21 CFR Part 812.3(k), blood sampling that involves simple venipuncture is 
considered noninvasive]; (iii) would not be used as a diagnostic procedure in our clinical study 
without confirmation of the diagnosis by another, medically established diagnostic procedure. 
6 
Data Safety Monitoring Plan 
A Data Safety Monitoring Plan will be developed for this study. 

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

7 
DATA ANALYSIS 
7.1 
Data Management 
7.1.1   Data Collection 
The subjects’ demographic and clinical data will be collected and documented on the case report 
form (CRF) specifically designed for this study. The data will be entered into a secure password 
protected clinical database. 
7.2 
Statistical Methods and Data Analysis for the RCT. 
7.2.1 
Endpoint 
This study’s primary outcome is duration of magnesium sulfate use in the postpartum period, 
expressed in hours. The decision to discontinue magnesium in the Cheetah arm will be based on 
demonstration of 30% reduction in SVR (maintained for 1 hour) from the time of delivery. 
7.2.2 
General statistical methods 
All summaries and analyses will be presented in tabular or graphical form. Data will be reported 
as mean ± standard deviation (SD), median [interquartile range] for continuous variables or 
number and percentage of subjects in each level of a categorical measurement. All statistical 
tests will be 2-tailed and performed at the 5% significance level, unless stated otherwise. 
7.2.3 
Demographics and baseline clinical variables 
Demographic and available baseline clinical variables will be summarized descriptively for each 
arm of the study. Differences in distributions of demographic and clinical variables between the 
two arms will be analyzed using either a 2-sample t-test or the Wilcoxon Rank Sum test, 
depending on the distribution of the data, for continuous variables, and the Chi-square or Fisher’s 
Exact tests for categorical variables as appropriate. 
7.2.4 
Primary efficacy analysis 
The primary outcome will be compared between the two study arms using either a 2-sample t- 
test or the Wilcoxon Rank Sum test, depending on the distribution of the data. Multivariate linear 
regression modeling adjusting for race, gestational weeks, body mass index (BMI, continuous), 
and other significant variables will provide the primary efficacy analysis for this study. All other 
analyses are considered exploratory. 
7.2.5 
Sample size assessment and feasibility 
Assuming an average reduction in magnesium sulfate use of 4 hours in the Cheetah® device 
group, alpha error of 5% and power of 90%, the study requires 21 patients in each arm. Allowing 
for 15% drop out, we plan to enroll a total of 60 patients. 
In addition to subjects enrolled in the RCT, we propose an optional negative control cohort of 25 
normotensive healthy women delivering > 37 weeks to compare hemodynamics. 
The OSUWMC is a tertiary care referral center for the central Ohio region, with a delivery 
volume more than 5200 patients per year. In addition, we receive close to 750 transfers per year 
for high risk conditions including preeclampsia. The total number of women admitted with 
preeclampsia yearly is more than 450 patients. Given the high prevalence of preeclampsia with 
severe features at our tertiary care center, we anticipate completion of enrollment within 1 year. 

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

8 
REFERENCES 
1.
Sanghavi M, Rutherford JD. Cardiovascular physiology of pregnancy. Circulation.
2014;130(12):1003–8.
2.
Tihtonen K, Kööbi T, Yli-Hankala A, Uotila J. Maternal hemodynamics during cesarean
delivery assessed by whole-body impedance cardiography. Acta Obstet Gynecol Scand.
2005;84(4):355–61.
3.
Milsom I, Forssman L, Biber B, Dottori O, Rydgren B, Sivertsson R. Maternal
Haemodynamic Changes during Caesarean Section: A Comparison of Epidural and
General Anaesthesia. Acta Anaesthesiol Scand. 1985;29(2):161–7.
4.
Espinoza J, Vidaeff A, Pettker CM, Simhan H. ACOG Practice Bulletin No. 202:
Gestational Hypertension and Preeclampsia. Obstet Gynecol. 2019;133(1):e1-25.
5.
Bellamy L, Casas JP, Hingorani AD, Williams DJ. Pre-eclampsia and risk of
cardiovascular disease and cancer in later life: Systematic review and meta-analysis.
BMJ. 2007;335(7627):974.
6.
Lavie A, Ram M, Lev S, Blecher Y, Amikam U, Shulman Y, et al. Maternal cardiovascular
hemodynamics in normotensive versus preeclamptic pregnancies: A prospective
longitudinal study using a noninvasive cardiac system (NICaSTM). BMC Pregnancy
Childbirth. 2018;18(1):1–11.
7.
Roberts JM. Pathophysiology of ischemic placental disease. Semin Perinatol.
2014;38(3):139–45.
8.
Herraiz I, Llurba E, Verlohren S, Galindo A, Bartha JL, De La Calle M, et al. Update on
the Diagnosis and Prognosis of Preeclampsia with the Aid of the sFlt-1/PlGF Ratio in
Singleton Pregnancies. Fetal Diagn Ther. 2018;43(2):81–9.
9.
Pryde PG, Mittendorf R. Contemporary usage of obstetric magnesium sulfate: Indication,
contraindication, and relevance of dose. Obstet Gynecol. 2009;114(3):669–73.
10.
Lu JF, Nightingale CH. Magnesium sulfate in eclampsia and pre-eclampsia:
Pharmacokinetic principles. Clin Pharmacokinet. 2000;38(4):305–14.
11.
Simon J, Gray A, Duley L. Cost-effectiveness of prophylactic magnesium sulphate for
9996 women with pre-eclampsia from 33 countries: Economic evaluation of the Magpie
Trial. BJOG An Int J Obstet Gynaecol. 2006;113(2):144–51.
12.
Maia SB, Katz L, Neto CN, Caiado BVR, Azevedo APRL, Amorim MMR. Abbreviated (12-
hour) versus traditional (24-hour) postpartum magnesium sulfate therapy in severe pre- 
eclampsia. Int J Gynecol Obstet. 2014;126(3):260–4.
13.
Vigil-De Gracia P, Ramirez R, Durán Y, Quintero A. Magnesium sulfate for 6 vs 24 hours
post delivery in patients who received magnesium sulfate for less than 8 hours before
birth: A randomized clinical trial. BMC Pregnancy Childbirth. 2017;17(1):241.
14.
Anjum S, Goel N, Sharma R, Mohsin Z, Garg N. Maternal outcomes after 12 hours and
24 hours of magnesium sulfate therapy for eclampsia. Int J Gynecol Obstet.
2016;132(1):68–71.
15.
Miles JF, Martin JN, Blake PG, Perry KG, Martin RW, Meeks GR. Postpartum eclampsia: A
recurring perinatal dilemma. Obstet Gynecol. 1990;76(3 Pt 1):328.

Clinical Protocol: Cheetah® OSU study 
9HUVLRQ

16.
Vinayagam D, Bowe S, Sheehan E, et al. Non-invasive haemodynamic monitoring in
pregnancy: a comparative study using ultrasdound and bioreactance. Fetl Diagn Ther
2017;41:272-282.