Advertisement
ORIGINAL ARTICLE| Volume 20, ISSUE 3, P224-228, July 2011

Serum oxytocin concentrations in elective caesarean delivery: a randomized comparison of three infusion regimens

      Abstract

      Background

      The aim of this study was to determine serum oxytocin concentrations following different regimens of prophylactic oxytocin administration in women undergoing elective caesarean delivery.

      Methods

      Thirty healthy pregnant patients were randomized, after clamping of the umbilical cord, to receive intravenous oxytocin in one of the following groups: G1 (n = 9), 10 IU of oxytocin infused over 30 min (0.33 IU/min); G2 (n = 11), 10 IU of oxytocin infused over 3 min and 45 s (2.67 IU/min); and G3 (n = 10), 80 IU of oxytocin infused over 30 min (2.67 IU/min). Both patient and surgeon were blinded to allocation. Uterine tone was assessed by surgical palpation. Serum oxytocin concentration was determined by enzyme immunoassay before anaesthesia (T0) and at 5 (T5), 30 (T30) and 60 (T60) min after the start of oxytocin infusion.

      Results

      Serum oxytocin concentrations (mean ± standard error, ng/mL) were not significantly different in the groups at T0 (0.06±0.02, 0.04±0.02 and 0.07±0.04, respectively, P = 0.76), and T60 (0.65±0.26, 0.36±0.26 and 0.69±0.26, respectively, P = 0.58). G3 showed higher concentrations than G1 at T5 (3.65±0.74 versus 0.71±0.27, P = 0.01) and at T30 (6.19±1.19 versus 1.17±0.37, P < 0.01), and were higher than G2 at T30 (6.19±1.19 versus 0.41±0.2, P < 0.01). Haemodynamic data and uterine tone were considered satisfactory and similar in all groups. No additional uterotonic agents were needed.

      Conclusion

      Serum oxytocin measurements made using enzyme immunoassay in healthy pregnant women undergoing elective caesarean delivery showed that administration of 80 IU oxytocin over 30 min resulted in higher serum oxytocin levels after 5 and 30 min than the two other regimens. The concentrations did not differ between groups at 60 min.

      Keywords

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'

      Subscribe:

      Subscribe to International Journal of Obstetric Anesthesia
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect

      References

        • Wedisinghe L.
        • Macleod M.
        • Murphy D.J.
        Use of oxytocin to prevent haemorrhage at caesarean section – a survey of practice in the United Kingdom.
        Eur J Obstet Gynecol Reprod Biol. 2008; 137: 27-30
        • Perry R.L.
        • Satin A.J.
        • Barth W.H.
        • Valtier S.
        • Cody J.T.
        • Hankins G.D.V.
        The pharmacokinetics of oxytocin as they apply to labor induction.
        Am J Obstet Gynecol. 1996; 174: 1590-1593
        • Thornton S.
        • Davison J.M.
        • Baylis P.H.
        Effect of human pregnancy on metabolic clearance rate of oxytocin.
        Am J Physiol. 1990; 259: R21-R24
        • Stocche R.M.
        • Garcia L.V.
        • Klamt J.G.
        Effects of analgesic intrathecal sufentanil and 0.25% epidural bupivacaine on oxytocin and cortisol plasma concentration in labor patients.
        Rev Bras Anestesiol. 2001; 51: 285-297
        • Kumaresan P.
        • Anandarangam P.B.
        • Dianzon W.
        • Vasicka A.
        Plasma oxytocin levels during human pregnancy and labor as determined by radioimmunoassay.
        Am J Obstet Gynecol. 1974; 119: 215-223
        • Prakash B.S.
        • Metten M.
        • Schams D.
        • Wuttke W.
        Development of a sensitive enzyme immunoassay for oxytocin determination in bovine plasma.
        Anim Reprod Sci. 1998; 51: 185-194
        • Gonser M.
        Labor induction and augmentation with oxytocin: pharmacokinetic considerations.
        Arch Gynecol Obstet. 1995; 256: 63-66
        • Munn M.B.
        • Owen J.
        • Vincent R.
        • Wakefield M.
        • Chestnut D.H.
        • Hauth J.C.
        Comparison of two oxytocin regimens to prevent uterine atony at cesarean delivery: a randomized controlled trial.
        Obstet Gynecol. 2001; 98: 386-390
        • Pinder A.J.
        • Dresner M.
        • Calow C.
        • O’Riordan J.
        • Johnson R.
        Haemodynamic changes caused by oxytocin during caesarean section under spinal anaesthesia.
        Int J Obstet Anesth. 2002; 11: 156-159
        • Sarna M.C.
        • Soni A.K.
        • Gomez M.
        • Oriol N.E.
        Intravenous oxytocin in patients undergoing elective cesarean section.
        Anesth Analg. 1997; 84: 753-756
        • Bolton T.J.
        • Randall K.
        • Yentis S.M.
        Effect of the Confidential Enquires into Maternal Deaths on the use of Syntocinon at Caesarean section in the UK.
        Anaesthesia. 2003; 58: 277-279
        • Tsen L.C.
        • Balki M.
        Oxytocin protocols during cesarean delivery: time to acknowledge the risk/benefit ratio?.
        Int J Obstet Anesth. 2010; 19: 243-245
        • Dyer R.A.
        • van Dyk D.
        • Dresner A.
        The use of uterotonic drugs during caesarean section.
        Int J Obstet Anesth. 2010; 19: 313-319
        • Dyer R.A.
        • Reed A.R.
        • van Dyk D.
        • et al.
        Hemodynamic effects of ephedrine, phenylephrine and the coadministration of phenylephrine with oxytocin during spinal anesthesia for elective cesarean delivery.
        Anesthesiology. 2009; 111: 753-765