Divergent effects of ephedrine and phenylephrine on cardiovascular hemodynamics of near-term fetal sheep exposed to hypoxemia and maternal hypotension

T. Erkinaro, K. Mäkikallio, G. Acharya, M. Päkkilä, T. Kavasmaa, J. C. Huhta, S. Alahuhta, Juha Rasanen

Research output: Contribution to journalArticle

20 Citations (Scopus)

Abstract

Background: We hypothesized that the administration of ephedrine and phenylephrine for maternal hypotension modifies cardiovascular hemodynamics in near-term sheep fetuses. Methods: At 115-136 days of gestation, chronically instrumented, anesthetized ewes with either normal placental function or increased placental vascular resistance after placental embolization were randomized to receive boluses of ephedrine (n = 12) or phenylephrine (n = 12) for epidural-induced hypotension after a short period of hypoxemia. Fetal cardiovascular hemodynamics were assessed by Doppler ultrasonography at baseline, during hypotension and after vasopressor treatment. Results: During hypotension, fetal PO2 decreased and proximal branch pulmonary arterial and pulmonary venous vascular impedances increased. Additionally, in the embolized fetuses, the time-velocity integral ratio between the antegrade and retrograde blood flow components of the aortic isthmus decreased. These parameters were restored to baseline conditions by ephedrine but not by phenylephrine. With phenylephrine, weight-indexed left ventricular cardiac output and ejection force decreased in the non-embolized fetuses, and the proportion of isovolumetric contraction time of the total cardiac cycle was elevated in the embolized fetuses. Conclusions: After exposure to hypoxemia and maternal hypotension, ephedrine restored all fetal cardiovascular hemodynamic parameters to baseline. Phenylephrine did not reverse fetal pulmonary vasoconstriction or the relative decrease in the net forward flow through the aortic isthmus observed in fetuses with increased placental vascular resistance. Moreover, fetal left ventricular function was impaired during phenylephrine administration.

Original languageEnglish (US)
Pages (from-to)922-928
Number of pages7
JournalActa Anaesthesiologica Scandinavica
Volume51
Issue number7
DOIs
StatePublished - Aug 2007
Externally publishedYes

Fingerprint

Ephedrine
Phenylephrine
Hypotension
Sheep
Hemodynamics
Mothers
Fetus
Vascular Resistance
Lung
Controlled Hypotension
Doppler Ultrasonography
Vasoconstriction
Electric Impedance
Left Ventricular Function
Cardiac Output
Blood Vessels
Hypoxia
Weights and Measures
Pregnancy

Keywords

  • Anesthesia
  • Anesthetic techniques
  • Doppler ultrasonography
  • Ephedrine
  • Epidural
  • Measurement techniques
  • Obstetric
  • Phenylephrine
  • Sympathetic nervous system

ASJC Scopus subject areas

  • Anesthesiology and Pain Medicine

Cite this

Divergent effects of ephedrine and phenylephrine on cardiovascular hemodynamics of near-term fetal sheep exposed to hypoxemia and maternal hypotension. / Erkinaro, T.; Mäkikallio, K.; Acharya, G.; Päkkilä, M.; Kavasmaa, T.; Huhta, J. C.; Alahuhta, S.; Rasanen, Juha.

In: Acta Anaesthesiologica Scandinavica, Vol. 51, No. 7, 08.2007, p. 922-928.

Research output: Contribution to journalArticle

Erkinaro, T. ; Mäkikallio, K. ; Acharya, G. ; Päkkilä, M. ; Kavasmaa, T. ; Huhta, J. C. ; Alahuhta, S. ; Rasanen, Juha. / Divergent effects of ephedrine and phenylephrine on cardiovascular hemodynamics of near-term fetal sheep exposed to hypoxemia and maternal hypotension. In: Acta Anaesthesiologica Scandinavica. 2007 ; Vol. 51, No. 7. pp. 922-928.
@article{1b64e810b243457d80cda98c58b2eec0,
title = "Divergent effects of ephedrine and phenylephrine on cardiovascular hemodynamics of near-term fetal sheep exposed to hypoxemia and maternal hypotension",
abstract = "Background: We hypothesized that the administration of ephedrine and phenylephrine for maternal hypotension modifies cardiovascular hemodynamics in near-term sheep fetuses. Methods: At 115-136 days of gestation, chronically instrumented, anesthetized ewes with either normal placental function or increased placental vascular resistance after placental embolization were randomized to receive boluses of ephedrine (n = 12) or phenylephrine (n = 12) for epidural-induced hypotension after a short period of hypoxemia. Fetal cardiovascular hemodynamics were assessed by Doppler ultrasonography at baseline, during hypotension and after vasopressor treatment. Results: During hypotension, fetal PO2 decreased and proximal branch pulmonary arterial and pulmonary venous vascular impedances increased. Additionally, in the embolized fetuses, the time-velocity integral ratio between the antegrade and retrograde blood flow components of the aortic isthmus decreased. These parameters were restored to baseline conditions by ephedrine but not by phenylephrine. With phenylephrine, weight-indexed left ventricular cardiac output and ejection force decreased in the non-embolized fetuses, and the proportion of isovolumetric contraction time of the total cardiac cycle was elevated in the embolized fetuses. Conclusions: After exposure to hypoxemia and maternal hypotension, ephedrine restored all fetal cardiovascular hemodynamic parameters to baseline. Phenylephrine did not reverse fetal pulmonary vasoconstriction or the relative decrease in the net forward flow through the aortic isthmus observed in fetuses with increased placental vascular resistance. Moreover, fetal left ventricular function was impaired during phenylephrine administration.",
keywords = "Anesthesia, Anesthetic techniques, Doppler ultrasonography, Ephedrine, Epidural, Measurement techniques, Obstetric, Phenylephrine, Sympathetic nervous system",
author = "T. Erkinaro and K. M{\"a}kikallio and G. Acharya and M. P{\"a}kkil{\"a} and T. Kavasmaa and Huhta, {J. C.} and S. Alahuhta and Juha Rasanen",
year = "2007",
month = "8",
doi = "10.1111/j.1399-6576.2007.01327.x",
language = "English (US)",
volume = "51",
pages = "922--928",
journal = "Acta Anaesthesiologica Scandinavica",
issn = "0001-5172",
publisher = "Blackwell Munksgaard",
number = "7",

}

TY - JOUR

T1 - Divergent effects of ephedrine and phenylephrine on cardiovascular hemodynamics of near-term fetal sheep exposed to hypoxemia and maternal hypotension

AU - Erkinaro, T.

AU - Mäkikallio, K.

AU - Acharya, G.

AU - Päkkilä, M.

AU - Kavasmaa, T.

AU - Huhta, J. C.

AU - Alahuhta, S.

AU - Rasanen, Juha

PY - 2007/8

Y1 - 2007/8

N2 - Background: We hypothesized that the administration of ephedrine and phenylephrine for maternal hypotension modifies cardiovascular hemodynamics in near-term sheep fetuses. Methods: At 115-136 days of gestation, chronically instrumented, anesthetized ewes with either normal placental function or increased placental vascular resistance after placental embolization were randomized to receive boluses of ephedrine (n = 12) or phenylephrine (n = 12) for epidural-induced hypotension after a short period of hypoxemia. Fetal cardiovascular hemodynamics were assessed by Doppler ultrasonography at baseline, during hypotension and after vasopressor treatment. Results: During hypotension, fetal PO2 decreased and proximal branch pulmonary arterial and pulmonary venous vascular impedances increased. Additionally, in the embolized fetuses, the time-velocity integral ratio between the antegrade and retrograde blood flow components of the aortic isthmus decreased. These parameters were restored to baseline conditions by ephedrine but not by phenylephrine. With phenylephrine, weight-indexed left ventricular cardiac output and ejection force decreased in the non-embolized fetuses, and the proportion of isovolumetric contraction time of the total cardiac cycle was elevated in the embolized fetuses. Conclusions: After exposure to hypoxemia and maternal hypotension, ephedrine restored all fetal cardiovascular hemodynamic parameters to baseline. Phenylephrine did not reverse fetal pulmonary vasoconstriction or the relative decrease in the net forward flow through the aortic isthmus observed in fetuses with increased placental vascular resistance. Moreover, fetal left ventricular function was impaired during phenylephrine administration.

AB - Background: We hypothesized that the administration of ephedrine and phenylephrine for maternal hypotension modifies cardiovascular hemodynamics in near-term sheep fetuses. Methods: At 115-136 days of gestation, chronically instrumented, anesthetized ewes with either normal placental function or increased placental vascular resistance after placental embolization were randomized to receive boluses of ephedrine (n = 12) or phenylephrine (n = 12) for epidural-induced hypotension after a short period of hypoxemia. Fetal cardiovascular hemodynamics were assessed by Doppler ultrasonography at baseline, during hypotension and after vasopressor treatment. Results: During hypotension, fetal PO2 decreased and proximal branch pulmonary arterial and pulmonary venous vascular impedances increased. Additionally, in the embolized fetuses, the time-velocity integral ratio between the antegrade and retrograde blood flow components of the aortic isthmus decreased. These parameters were restored to baseline conditions by ephedrine but not by phenylephrine. With phenylephrine, weight-indexed left ventricular cardiac output and ejection force decreased in the non-embolized fetuses, and the proportion of isovolumetric contraction time of the total cardiac cycle was elevated in the embolized fetuses. Conclusions: After exposure to hypoxemia and maternal hypotension, ephedrine restored all fetal cardiovascular hemodynamic parameters to baseline. Phenylephrine did not reverse fetal pulmonary vasoconstriction or the relative decrease in the net forward flow through the aortic isthmus observed in fetuses with increased placental vascular resistance. Moreover, fetal left ventricular function was impaired during phenylephrine administration.

KW - Anesthesia

KW - Anesthetic techniques

KW - Doppler ultrasonography

KW - Ephedrine

KW - Epidural

KW - Measurement techniques

KW - Obstetric

KW - Phenylephrine

KW - Sympathetic nervous system

UR - http://www.scopus.com/inward/record.url?scp=34447318341&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=34447318341&partnerID=8YFLogxK

U2 - 10.1111/j.1399-6576.2007.01327.x

DO - 10.1111/j.1399-6576.2007.01327.x

M3 - Article

VL - 51

SP - 922

EP - 928

JO - Acta Anaesthesiologica Scandinavica

JF - Acta Anaesthesiologica Scandinavica

SN - 0001-5172

IS - 7

ER -