Maternal haemodynamics at elective caesarean section: a randomised comparison of oxytocin 5-unit bolus and placebo infusion with oxytocin 5-unit bolus and 30-unit infusion

G. McLeod, B. Munishankar, H. MacGregor, D. J. Murphy

    Research output: Contribution to journalArticle

    13 Citations (Scopus)

    Abstract

    Background: Rapid intravenous injection of oxytocin is associated with marked hypotension secondary to decreased venous return. Reductions in dose and rate of bolus administration have reduced the incidence of cardiovascular side effects, but no study has yet investigated cardiovascular stability when oxytocin is infused for several hours after delivery. This study compared maternal haemodynamics during a 4-h 30-unit oxytocin infusion and during a placebo infusion following caesarean section. Methods: Women booked for elective caesarean section were randomised to receive either oxytocin 5-unit bolus and placebo infusion or oxytocin 5-unit bolus and oxytocin 30-unit infusion. Before, during and for 4 h after surgery electrocardiogram, oxygen saturation, systolic and diastolic pressure and heart rate were monitored non-invasively and cardiac index (CI), left ventricular work index (LVWi) and systemic vascular resistance index (SVRi) by thoracic bioimpedance. Results: A total of 74 women agreed to haemodynamic measurements. Heart rate, systolic and diastolic pressure, CI, LCWi and SVRi all fell following the onset of spinal anaesthesia, and, with the exception of SVRi, continued to decrease throughout surgery. After delivery of the baby, slow injection of oxytocin 5 units was associated with a temporary rise in CI, LCWi and heart rate, a decrease in SVRi and no change in systolic or diastolic pressure. Thereafter, haemodynamic measures returned to normal over 60 min with no adverse effects apparent from the additional oxytocin infusion. Conclusions: An additional oxytocin infusion at elective caesarean section did not adversely affect maternal haemodynamics either during or after surgery. © 2009 Elsevier Ltd. All rights reserved.
    Original languageEnglish
    Pages (from-to)155-160
    Number of pages6
    JournalInternational Journal of Obstetric Anesthesia
    Volume19
    Issue number2
    DOIs
    Publication statusPublished - Apr 2010

    Keywords

    • Adult
    • Analysis of variance
    • Anesthesia, Spinal
    • Area under curve
    • Cardiography, Impedance
    • Cesarean Section
    • Dose-response relationship, Drug
    • Female
    • Hemodynamics
    • Humans
    • Hypotension
    • Infusions, Intravenous
    • Oxygen
    • Oxytocics
    • Oxytocin
    • Surgical Procedures, Elective
    • Time factors
    • Treatment outcome
    • Young adult

    Fingerprint Dive into the research topics of 'Maternal haemodynamics at elective caesarean section: a randomised comparison of oxytocin 5-unit bolus and placebo infusion with oxytocin 5-unit bolus and 30-unit infusion'. Together they form a unique fingerprint.

  • Cite this