Oxytocin at Elective Cesarean Deliveries: A Dose-finding Study in Women With Twin Pregnancy
Condition: Postpartum Hemorrhage; Twin
MeSH terms: Postpartum Hemorrhage; Hemorrhage
Study type: Interventional

Summary: 
      Postpartum hemorrhage (PPH) due to uterine atony is a major cause of maternal morbidity and
      mortality. Uterotonic drugs are used to improve the muscle tone of the uterus after birth and
      these are effective at reducing the incidence of PPH. Large doses of this drug are associated
      with adverse effects like lower blood pressure, nausea, vomiting, abnormal heart rhythms and
      changes on ECG. Various international bodies recommend varying and high doses of oxytocin in
      elective cesarean sections. A study performed at Mount Sinai Hospital showed that a much
      smaller doses of oxytocin is required (ED95 being 0.35IU). Women who had twins were excluded
      from this study. It is known that women with a twin pregnancy have a higher risk of poor tone
      and postpartum hemorrhage.

      The investigators seek to find the best dose of oxytocin for the patients with a twin
      pregnancy. A higher dose may be needed to contract the uterus adequately.
    

Detailed description: 
      Postpartum hemorrhage (PPH) is one of the leading causes of death during childbirth and
      accounts for an estimated 140,000 deaths per year worldwide. Furthermore, recent evidence has
      shown that the rate of PPH secondary to uterine atony is increasing.

      Multiple pregnancy is a well-recognized risk factor for PPH. Compared with singleton
      pregnancy, women with a multiple pregnancy have an increased risk of PPH, severe PPH,
      transfusion, uterine atony, hysterectomy, prolonged hospital stay and death. This is true in
      both high- and low-income countries. Uterine atony as a cause of PPH is more likely in
      multiple pregnancy compared with singleton pregnancy.

      Prophylactic uterotonic drugs administered after the delivery have been demonstrated to
      reduce the incidence of PPH by up to 40%. Oxytocin is the most commonly administered
      uterotonic drug used to prevent PPH in North America but is associated with adverse effects
      such as hypotension, nausea, vomiting, dysrhythmias, ST segment abnormalities, and severe
      water intoxication that may lead to pulmonary edema and convulsions.

      Previous dose finding studies have excluded women with twin pregnancies. Therefore, the
      investigators wish to perform a double blinded dose finding study using the biased coin flip
      up-and-down sequential allocation technique to determine the ED 90 of oxytocin at cesarean
      section in those women with a twin pregnancy.
    

Intervention name(s): Oxytocin
Intervention type(s): Drug
Intervention description(s): Oxytocin administered intravenously, over 1 minute following delivery of the fetal head
Other intervention name(s): pitocin
Intervention MeSH terms: Oxytocin
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Biased coin up-and-down design.
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: pregnancy; twin; postpartum hemorrhage; oxytocin; Cesarean delivery