Abstract
Background
Aortocaval compression is a major cause of maternal hypotension. A randomized controlled
trial was designed to determine the effectiveness of a mechanical intervention using
a right lumbar–pelvic wedge in preventing hypotension after spinal anesthesia for
cesarean delivery.
Methods
Eighty healthy women undergoing elective cesarean section were randomly allocated
immediately after spinal blockade to either a lumbar–pelvic wedge positioned under
the right posterior–superior iliac crest (Wedge group, n = 40) or the complete supine position (Supine group, n = 40). Hemodynamic values, vasopressor consumption and adverse effects were collected
during the surgical procedure. Hypotension was defined as a reduction in systolic
blood pressure of 25% from baseline. Patient allocation, management and data collection
were performed by a single unblinded anesthetist.
Results
There was no difference in the incidence of hypotension between the two groups (42.5%
vs. 50%, P = 0.51). During the first 5 min, blood pressure decreased less in the Wedge group. There were significant differences
in median [interquartile range] vasopressor requirements between the Wedge group and
the Supine group (1 [0–2] vs. 3 [1–4] mg, P < 0.01) and in nausea during the procedure (6 vs. 22 patients, P < 0.01).
Conclusion
In our study population the use of right lumbar–pelvic wedge was not effective in
reducing the incidence of hypotension during spinal anesthesia for cesarean section.
Patients in whom the wedge was used had higher systolic blood pressure values during
the first 5 min of anesthesia and fewer episodes of nausea. The risk of hypotension remains substantial.
Keywords
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Article info
Publication history
Published online: August 18, 2011
Accepted:
June 28,
2011
Identification
Copyright
© 2011 Elsevier Ltd. Published by Elsevier Inc. All rights reserved.
