Intrauterine Resuscitation
Conditions
Brief summary
Approximately 2/3 of laboring women receive supplemental oxygen (O2) in an attempt to reverse perceived fetal hypoxia on electronic fetal monitoring (EFM). O2 supplementation is most commonly used in patients with Category II EFM, a class of EFM patterns designed in part to identify fetal acidemia. This liberal use of O2 in laboring patients is concerning because hyperoxygenation in infants is associated with adverse outcomes including retinopathy and abnormal neurodevelopment. Furthermore, excess O2 exposure is linked to free radical generation and subsequent oxidative cell damage. This calls for a closer look at the safety of intrauterine O2 exposure. The proposed project explores potential mechanisms for harm with maternal O2 supplementation in laboring patients with Category II EFM. Specifically, this project will determine the effect of O2, compared to room air (RA), on umbilical cord and maternal levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), markers of free radical-induced oxidative stress. The study will also explore the correlation between urinary and blood markers of oxidative stress. Banked specimens will be used to investigate the potential effect of peripartum O2 exposure on placental oxidative stress in the future.
Interventions
OTHERNo oxygen
No facemask, room air only
OTHEROxygen
10Liters/minute oxygen by facemask
Sponsors
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
Washington University School of Medicine
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Singleton * Gestational age ≥37 weeks * Spontaneous labor or induction of labor * English speaking * Ability to give informed consent
Exclusion criteria
* Major fetal anomaly * Multiple gestation * Category III electronic fetal monitoring * Maternal hypoxia * Preeclampsia * Intrauterine growth restriction * Pregestational diabetes * Tobacco use
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Umbilical Artery Malondialdehyde | At delivery |
| Umbilical Artery 4-hydroxynonenal | At delivery |
| Maternal Malondialdehyde | Within 1 hour of delivery |
| Maternal 4-hydroxynonenal | Within 1 hour of delivery |
Countries
United States
Participant flow
Pre-assignment details
910 patients were enrolled. Of these, 698 did not get randomized. This was mostly because they did not ultimately meet randomization criteria (N=669), research staff were not available (N=53), or other logistical reasons (N=33).Of the 910 patients enrolled, 212 were randomized and included in the final analysis.
Participants by arm
| Arm | Count |
|---|---|
| Room Air Room air (no mask)
No oxygen: No facemask, room air only | 102 |
| Oxygen 10L/min Oxygen by facemask
Oxygen: 10Liters/minute oxygen by facemask | 104 |
| Total | 206 |
Baseline characteristics
| Characteristic | Room Air | Oxygen | Total |
|---|---|---|---|
| Age, Continuous | 27.1 years STANDARD_DEVIATION 5.5 | 27.2 years STANDARD_DEVIATION 5.8 | 27.1 years STANDARD_DEVIATION 5.6 |
| Chronic Hypertension | 3 Participants | 7 Participants | 10 Participants |
| Epidural | 97 Participants | 99 Participants | 196 Participants |
| Gestational diabetes | 6 Participants | 8 Participants | 14 Participants |
| Induction of labor | 71 Participants | 78 Participants | 149 Participants |
| Insurance Other | 0 Participants | 1 Participants | 1 Participants |
| Insurance Private | 48 Participants | 46 Participants | 94 Participants |
| Insurance Public | 46 Participants | 47 Participants | 93 Participants |
| Insurance Uninsured | 8 Participants | 10 Participants | 18 Participants |
| Nulliparous | 56 Participants | 59 Participants | 115 Participants |
| Oxytocin | 96 Participants | 94 Participants | 190 Participants |
| Pre-pregnancy obesity | 31 Participants | 43 Participants | 74 Participants |
| Race/Ethnicity, Customized African American | 48 Participants | 48 Participants | 96 Participants |
| Race/Ethnicity, Customized Asian | 3 Participants | 4 Participants | 7 Participants |
| Race/Ethnicity, Customized Other | 5 Participants | 4 Participants | 9 Participants |
| Race/Ethnicity, Customized White | 45 Participants | 48 Participants | 93 Participants |
| Region of Enrollment United States | 102 participants | 104 participants | 206 participants |
| Sex: Female, Male Female | 102 Participants | 104 Participants | 206 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 102 | 0 / 104 |
| other Total, other adverse events | 5 / 102 | 3 / 104 |
| serious Total, serious adverse events | 0 / 102 | 0 / 104 |
Outcome results
Primary
Maternal 4-hydroxynonenal
Time frame: Within 1 hour of delivery
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Room Air | Maternal 4-hydroxynonenal | 190.4 pg/ml |
| Oxygen | Maternal 4-hydroxynonenal | 168.1 pg/ml |
Primary
Maternal Malondialdehyde
Time frame: Within 1 hour of delivery
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Room Air | Maternal Malondialdehyde | 2.8 mmol/L |
| Oxygen | Maternal Malondialdehyde | 2.5 mmol/L |
Primary
Umbilical Artery 4-hydroxynonenal
Time frame: At delivery
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Room Air | Umbilical Artery 4-hydroxynonenal | 34.1 pg/ml |
| Oxygen | Umbilical Artery 4-hydroxynonenal | 29.5 pg/ml |
Primary
Umbilical Artery Malondialdehyde
Time frame: At delivery
| Arm | Measure | Value (MEDIAN) |
|---|---|---|
| Room Air | Umbilical Artery Malondialdehyde | 9.8 umol/L |
| Oxygen | Umbilical Artery Malondialdehyde | 10.2 umol/L |