TY - JOUR
T1 - Maternal haemodynamics at elective caesarean section
T2 - a randomised comparison of oxytocin 5-unit bolus and placebo infusion with oxytocin 5-unit bolus and 30-unit infusion
AU - McLeod, G.
AU - Munishankar, B.
AU - MacGregor, H.
AU - Murphy, D. J.
N1 - Copyright 2009 Elsevier Ltd. All rights reserved.
PY - 2010/4
Y1 - 2010/4
N2 - 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.
AB - 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.
KW - Adult
KW - Analysis of variance
KW - Anesthesia, Spinal
KW - Area under curve
KW - Cardiography, Impedance
KW - Cesarean Section
KW - Dose-response relationship, Drug
KW - Female
KW - Hemodynamics
KW - Humans
KW - Hypotension
KW - Infusions, Intravenous
KW - Oxygen
KW - Oxytocics
KW - Oxytocin
KW - Surgical Procedures, Elective
KW - Time factors
KW - Treatment outcome
KW - Young adult
UR - http://www.scopus.com/inward/record.url?scp=77949774658&partnerID=8YFLogxK
U2 - 10.1016/j.ijoa.2009.08.005
DO - 10.1016/j.ijoa.2009.08.005
M3 - Article
C2 - 20194013
SN - 0959-289X
VL - 19
SP - 155
EP - 160
JO - International Journal of Obstetric Anesthesia
JF - International Journal of Obstetric Anesthesia
IS - 2
ER -