Different Approaches to Maternal Hypotension During Cesarean Section
Condition: Pregnancy; Cesarean Section; Anesthesia,Spinal; Hypotension
MeSH terms: Hypotension
Study type: Interventional
Phase: Phase 4

Summary: 
      The aim of this study is to compare two different therapeutic approaches to blood pressure
      reduction: pharmacological vs. non-pharmacological. The setting is that of patients
      undergoing scheduled Cesarean section under spinal anesthesia and suffering from aorta-caval
      compression syndrome, which causes a sudden drop in blood pressure.
    

Detailed description: 
      The supine hypotensive syndrome of pregnancy is induced by compression of the inferior caval
      vein by the enlarged uterus. It occurs in approximately 8% of pregnant women at term. More
      patients may develop an asymptomatic variety of this syndrome in the supine position. The
      hypotensive effect of spinal anesthesia per se may thus be aggravated in a significant number
      of term parturients. A preoperative supine stress test (SST) before elective cesarean section
      under spinal anesthesia has been shown to predict severe systolic hypotension with reasonable
      accuracy.

      Different strategies have been proposed for the management of this complication; they can be
      divided into pharmacological and non-pharmacological ones.

      According to pharmacological strategies, vasoactive drugs are used to treat hypotension
      induced by sympathetic efferent blockade following spinal anesthesia. To this end, α-agonist
      ephedrine is commonly considered the best choice because of its minimal impact on the
      fetoplacental circulation. However, excessive use of ephedrine may be detrimental to neonatal
      well-being because of its vasoconstrictor effect on fetoplacental circulation.

      Non-pharmacological treatments may represent a valuable, safer alternative. According to many
      authors non-pharmacological treatments aimed at removing the cause of aorta-caval compression
      syndrome are to be preferred because more appropriate from an etiopathogenetic point of view.
      The use of a wedge-shaped cushion placed under the right hip is a well-known
      non-pharmacological strategy which allows the uterine left lateral displacement and,
      consequently, the removing of the compression from the inferior vena cava.

      The aim of the present study is to compare, through the evaluation of neonatal well-being,
      the efficacy of these approaches to hypotension after spinal anesthesia for elective
      Caesarean section in parturients affected by aorto-caval compression.
    

Intervention name(s): Bupivacaine; Morphine; Lactated Ringer's solution; Ephedrine, continuous infusion; Ephedrine, bolus; Atropine
Intervention type(s): Drug; Drug; Drug; Drug; Drug; Drug
Intervention description(s): 10 mg of a 5 mg/ml hyperbaric solution, intrathecally; 200 µg of a 100 µg/ml solution, intrathecally; 25 ml/min intravenously; 37.5 mg/h intravenously; 6.25 mg IV bolus prn.
Hypotension defined according to study protocol for each arm.; 0.1 mg/kg iv bolus prn
Bradycardia defined as 50% drop in heart rate from baseline values.
Other intervention name(s): Marcain; Local Anesthetic; Intrathecal morphine
Intervention MeSH terms: Atropine; Ephedrine; Pseudoephedrine; Morphine; Bupivacaine; Anesthetics, Local; Anesthetics
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Outcomes Assessor)
Primary purpose: Treatment
Keywords: Ephedrine; Adrenergic Agents; Central Nervous System Stimulants; Sympathomimetics; Vasoconstrictor Agents; Bupivacaine; Anesthetics, Local; Atropine; Adjuvants, Anesthesia; Anti-Arrhythmia Agents; Bronchodilator Agents; Muscarinic Antagonists; Mydriatics; Parasympatholytics; Morphine; Analgesics, Opioid; Narcotics; Ringer's Lactate; Isotonic Solutions; Hypotension; Blood pressure; Signs and Symptoms; Pregnancy; Anesthesia, Obstetrical; Inferior Vena Cava