Cardiac Index Changes With Ephedrine, Phenylephrine, Ondansetron and Norepinephrine During Spinal Anesthesia
Condition: Cardiac Output, Low
MeSH terms: Cardiac Output, Low
Study type: Interventional
Phase: Phase 4

Summary: 
      The purpose of the study is to evaluate the cardiac output changes after an intravenous bolus
      of ephedrine, phenylephrine, ondansetron or norepinephrine during a spinal anesthetic for a
      cesarean delivery.

      For elective cesarean delivery, all participants will receive spinal anesthesia with a local
      anesthetic and sufentanil. This study includes 120 pregnant women. Patients will be randomly
      assigned according to a computer generated system to be in one of four groups.
    

Detailed description: 
      This study will be a prospective, randomized, double-blind controlled trial. After written
      and informed consent are obtained, the study participants are randomly assigned using a
      computer generated table to 1 of 4 treatment groups prior to cesarean delivery.

      Group A: 9 mg of ephedrine Group B: 100 mcg of phenylephrine Group C: 8 mg of ondansetron
      Group D: 0,25 mcg/kg of norepinephrine Baseline arterial blood pressure and heart rate will
      be measured in the left lateral tilt position, before anesthesia and then every minute.The
      cardiac output is calculated on the apical cut 5 cavities, before anesthesia and then every 5
      miutes. No fluid preloading will be administered till delivery.

      The primary endpoint is cardiac output changes in each groups. The secondary endpoint is the
      number of provider interventions needed to maintain the SBP within 80-120% of baseline for
      each groups.

      Bradycardia (HR less than 50 BPM) will be treated with 1 mg of Atropine. Hypotension (
      decrease of more than 20% of the baseline value or a PAS <90 mm Hg) will be treated with 6 mg
      of ephedrine, without any fluid loading.

      The spinal anesthesia will be carried out in a seated position, level L3-L4 or L4-L5 with a
      slow injection over 30 seconds of a mixture of 10 mg of 0.5% Bupivacaine with 5 mcg of
      Sufentanil. The hot / cold test to determine the block level is required. A spinal anesthesia
      is validated if the cold test reaches the T4 level. The 10 ml syringe will be administered
      immediately after spinal anesthesia. The patient will be placed in the left lateral tilt
      position of 15¤, then put back into strict DD immediately after the delivery. Cardiovascular
      parameters (PAS, PAM, PAD, HR) will be recorded every minute until delivery.
      Echocardiographic measurement of cardiac output will be recorded every five minutes until
      delivery.

      Measured variables will include systolic, diastolic and mean non-invasive blood pressure, the
      number and type of interventions for control of blood pressure, heart rate, cardiac output,
      incidence of nausea and vomiting (NV), incidence of arrhythmia and fetal cord blood analysis
      (pH) at delivery.
    

Intervention name(s): cardiac output changes with "ephedrine"; cardiac output changes with "phenylephrine"; cardiac output changes with "ondansetron"; cardiac output changes with "nor-epinephrine"
Intervention type(s): Drug; Drug; Drug; Drug
Intervention description(s): measure cardiac output after giving a bolus of ephedrine intervention: will receive complementary doses of ephedrine to maintain systolic blood pressure above 80 % of baseline; measure cardiac output after giving a bolus of phenylephrine intervention: will receive complementary doses of ephedrine to maintain systolic blood pressure above 80 % of baseline; measure cardiac output after giving a bolus of ondansetron intervention: will receive complementary doses of ephedrine to maintain systolic blood pressure above 80 % of baseline; measure cardiac output after giving a bolus of nor-epinephrine intervention: will receive complementary doses of ephedrine to maintain systolic blood pressure above 80 % of baseline
Other intervention name(s): cardiac output: CO (cm3 / min) = ITV * S * HR . ITV (cm) = integral time velocity is measured by pulsed doppler at the level of the ascending aorta, on apical cut.; cardiac output: CO (cm3 / min) = ITV * S * HR. ITV (cm) = integral time velocity is measured by pulsed doppler at the level of the ascending aorta, on apical cut.; cardiac output: CO (cm3 / min) = ITV * S * HR. ITV (cm) = integral time velocity is measured by pulsed doppler at the level of the ascending aorta, on apical cut.; cardiac output: CO (cm3 / min) = ITV * S * HR. ITV (cm) = integral time velocity is measured by pulsed doppler at the level of the ascending aorta, on apical cut.
Intervention MeSH terms: Phenylephrine; Epinephrine; Oxymetazoline; Ephedrine; Norepinephrine; Ondansetron
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Treatment
Keywords: Spinal anesthesia; cardiac output; vasopressor