High Dose vs. Low Dose Oxytocin for Labor Induction in Obese Women: a Randomized Controlled Trial - the OPS (Obese Pitocin Study) Trial
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 140
- 试验地点
- 1
- 主要终点
- Length of Time to Delivery
研究概览
简要总结
This is a randomized controlled trial in which women are allocated either 'high dose' or 'low dose' oxytocin infusions for induction of labour. The randomization is stratified by maternal body mass index.
详细描述
Obesity is considered a major public health concerns and increases the risk of many comorbid medical conditions. Obesity in pregnancy places women at higher risk of obstetrical complications during pregnancy, delivery and postpartum. In particular, obese pregnant women have more difficulty going into labor, a longer labor course, and even with pharmacologic treatment, have a higher chance of requiring cesarean delivery.
When pregnant women need help going into labor, they commonly receive a medication called Pitocin on the labor and delivery floor. Pitocin is the brand name and is a synthetic analog to the naturally produced oxytocin, a hormone secreted by mother when they naturally go into labor. This medication has been used widely around the world. There is emerging evidence that obese women need more oxytocin to go into labor compared to their lean cohorts. There are many studies to support the use of different oxytocin dosage protocols (both high and low dose infusion increments). Despite these evidences, a low dose oxytocin regimen is universally used in the United States, regardless of patient characteristics.
This study is a double blinded randomized controlled trial. Both lean and obese cohorts will be recruited for the study. The investigators will randomly place both cohorts into the low or the high dose oxytocin regimen treatment group. The investigators, patients and providers will be blinded and will not know the specific assignments. The purpose of this study is to evaluate the effect of high dose oxytocin in the obese cohort. The hypothesis is that obese patient will have shorter time to delivery with the high dose oxytocin regimen without incurring any additional risks or adverse outcomes.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Other
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
盲法说明
This portion of the study will be carried out by the research pharmacy. Single (low dose) and triple (high dose) concentration of oxytocin will be premixed in the intravenous fluid bag in the pharmacy. Sequence generation for randomization will be created with 1:1 ratio in both the obese and lean group by the Department of Statistics. After the sequence is generated, ths list will be given to the research pharmacy. The premixed oxytocin medication will be sequentially labelled as "OPS drug, patient #1, 2, 3" etc. per the allocation. Allocation concealment will also be carried out by pharmacy as these bags will completely appear identical after they are labelled numerically. Once a patient is randomized, the pharmacy will send up the appropriate concentration of oxytocin already premixed in the intravenous fluid bag, labelled as "OPS drug, patient #". Lean group will be assigned at # 1-70 and obese group will be assigned at #71-140.
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- Female
- 接受健康志愿者
- 否
入选标准
- •Singleton pregnancy ≥ 37 weeks gestation
- •Patient presented for induction of labor who is determined to be a candidate for oxytocin
- •Cephalic presentation
- •Reassuring fetal health assessment (no abnormal findings in fetal assessment, see below)
- •Meeting one of the following BMI category:
- •Obese group: BMI ≥30 at <20 weeks of pregnancy, or BMI ≥35 at a term gestation of pregnancy Lean group: BMI ≤25 at <20 weeks of pregnancy, or BMI ≤28 at a term gestation of pregnancy
排除标准
- •Non-reassuring fetal assessment at the time of recruitment
- •Previous cervical ripening agents (cytotec, cervidil, cervical Foley Balloon)
- •<18 years of age
- •Prisoners
- •Any patients contraindicated for vaginal delivery
- •Multiple gestations
- •History of previous cesarean delivery
- •Patients with history of significant cardiac disease
- •Fetal demise
- •Estimated fetal weight greater than 4500 grams in diabetic and 5000 grams in non-diabetic mother
- •Ruptured membranes
- •Spontaneous labor (latent or active phase)
- •Augmentation of labor (latent or active phase)
研究组 & 干预措施
Lean-Control
- Control group: Lean cohort: BMI ≤25, at <20 weeks gestation or BMI ≤28 at a term gestation, low dose oxytocin protocol
Low dose oxytocin regimen (the standard at Banner University Labor and Delivery, as well as across the United States): 30 units in 500cc 0.9% normal saline bag (60 milliunit/cc). Starting rate would be 2 milliunit/minute, or 2cc/hour. The medication will be increased by 2 milliunit/minute = 2cc/hr every 30 minutes until adequacy of contraction or cervical change. At 20 milliunit/minute = 20cc/hr, provider will assess patient for eligibility to continue to increase oxytocin dosage.
干预措施: Oxytocin (Drug)
Lean-Intervention
- Intervention group: Lean cohort: BMI ≤25, at <20 weeks gestation or BMI ≤28 at a term gestation, high dose oxytocin protocol
High dose oxytocin regimen (endorsed by American College of Obstetricians and Gynecologists): 90 units in 500cc 0.9% normal saline bag (180 milliunit/cc). Starting rate would be 6 milliunit/minute, or 2cc/hour. The medication will be increased by 6 milliunit/minute = 2cc/hr every 30 minutes until adequacy of contraction or cervical change. At 60 milliunit/minute = 20cc/hr, provider will assess patient for eligibility to continue to increase oxytocin dosage.
干预措施: Oxytocin (Drug)
Obese-Control
- Control group: Obese cohort: BMI ≥30, at <20 weeks gestation or BMI ≥35 at a term gestation, low dose oxytocin protocol
Low dose oxytocin regimen (the standard at Banner University Labor and Delivery, as well as across the United States): 30 units in 500cc 0.9% normal saline bag (60 milliunit/cc). Starting rate would be 2 milliunit/minute, or 2cc/hour. The medication will be increased by 2 milliunit/minute = 2cc/hr every 30 minutes until adequacy of contraction or cervical change. At 20 milliunit/minute = 20cc/hr, provider will assess patient for eligibility to continue to increase oxytocin dosage.
干预措施: Oxytocin (Drug)
Obese-Intervention
- Intervention group: Obese cohort: BMI ≥30, at <20 weeks gestation or BMI ≥35 at a term gestation, high dose oxytocin protocol
High dose oxytocin regimen (endorsed by American College of Obstetricians and Gynecologists): 90 units in 500cc 0.9% normal saline bag (180 milliunit/cc). Starting rate would be 6 milliunit/minute, or 2cc/hour. The medication will be increased by 6 milliunit/minute = 2cc/hr every 30 minutes until adequacy of contraction or cervical change. At 60 milliunit/minute = 20cc/hr, provider will assess patient for eligibility to continue to increase oxytocin dosage.
干预措施: Oxytocin (Drug)
结局指标
主要结局
Length of Time to Delivery
时间窗: Start of induction to Delivery
Number of minutes from induction of labor with oxytocin infusion to delivery of infant, no maximum amount of time specified.
次要结局
- Number of Participants With Terbutaline Use(Start of induction to Delivery)
- Rate of Cesarean Delivery(Start of induction to Delivery)
- Rate of Cesarean Delivery for Labor Arrest(Start of induction to Delivery)
- Maximum Oxytocin Infusion Rate(Start of induction to Delivery)
- Maternal Blood Loss(At delivery)
- Number of Neonates With Apgar Score <7(5 minutes after birth)
研究者
Meghan Hill
Assistant Professor
University of Arizona