Does the Addition of Epinephrine Prolong the Duration of Spinal Anesthesia for Repeat Cesarean Section?
Condition: Spinal Anesthesia; Cesarean Section
Study type: Interventional
Phase: Phase 4

Summary: 
      The purpose of this study is to investigate whether the addition of a medication called
      epinephrine to spinal medications prolongs the duration of the anesthesia. The medication
      standardly used in spinal anesthesia is a local anesthetic (bupivacaine) and an opiate pain
      medication (morphine). These medications typically last about 2 hours. The investigators want
      to determine if adding epinephrine to the spinal medications prolongs the anesthetic without
      side effects. A longer duration of anesthesia may be useful in prolonged repeat cesarean
      section. Epinephrine is known to prolong the action of some local anesthetics, but the
      investigators want to specifically study combining it with the medications the investigators
      use regularly for cesarean section.

      You may qualify to take part in this research study because you are having a repeat cesarean
      section. Repeat cesarean sections sometimes last longer than 2 hours. The investigators want
      to determine if epinephrine will prolong the anesthetic.
    

Detailed description: 
      Spinal anesthesia with bupivacaine is a commonly used anesthetic in the obstetric population.
      It is most frequently carried out as a single shot intrathecal injection. This method can be
      utilized for both labor analgesia and surgical anesthesia for cesarean section. One of the
      concerns in using a single shot spinal injection for surgical anesthesia is the duration of
      adequate surgical conditions. This concern is especially relevant to repeat cesarean
      sections, as each subsequent procedure has the potential to be more complex than the prior
      and, therefore, prolonged. A reliable way to prolong surgical anesthesia provided by single
      shot spinal injection of bupivacaine could prove invaluable in the setting of repeat cesarean
      section. It has been well documented that adding epinephrine to intrathecal lidocaine will
      increase its duration1, but the evidence for augmenting the duration of anesthesia provided
      by adding epinephrine to bupivacaine is much more equivocal and less robust. This is a
      randomized control trial investigating whether or not adding epinephrine to a standard single
      intrathecal injection of hyperbaric bupivacaine for repeat cesarean will prolong its
      duration. It will be investigated using women who are undergoing scheduled repeat cesarean
      section in whom neuraxial anesthesia is the appropriate primary anesthetic. The investigators
      will compare the onset, quality and duration of both sensory and motor components of the
      spinal block as well as the incidence of known side effects.
    

Intervention name(s): Low-dose epinephrine; High-dose epinephrine; No epinephrine
Intervention type(s): Drug; Drug; Drug
Intervention description(s): 0.1ml of preservative-free saline and 0.1ml of 1:1000 epinephrine will be added to the standard spinal medications; 0.2ml of 1:1000 epinephrine will be added to the standard spinal medications; 0.2ml of preservative-free saline will be added to the standard spinal medications
Other intervention name(s): adrenaline; preservative-free saline
Intervention MeSH terms: Epinephrine; Racepinephrine; Epinephryl borate
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Supportive Care
Keywords: spinal anesthesia; epinephrine; bupivacaine; repeat cesarean