Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1993 Aug;79(2):262-9.
doi: 10.1097/00000542-199308000-00011.

A reevaluation of the role of crystalloid preload in the prevention of hypotension associated with spinal anesthesia for elective cesarean section

Affiliations

A reevaluation of the role of crystalloid preload in the prevention of hypotension associated with spinal anesthesia for elective cesarean section

C C Rout et al. Anesthesiology. 1993 Aug.

Erratum in

  • Anesthesiology 1994 Aug;81(2):529

Abstract

Background: Hypotension after spinal anesthesia for cesarean section remains a common and serious complication despite the use of uterine displacement and volume preloading. The current study revaluated the role of crystalloid volume preloading in this context.

Methods: In a two-stage open sequential design, patients presenting for elective repeat cesarean section were allocated to receive either no preload or 20 ml/kg crystalloid administered over 15-20 min before spinal anesthesia. Hypotension was defined as a decrease in systolic pressure to less than 100 mmHg and to less than 80% of baseline value, and the study was designed to detect a 20% difference in the incidence of hypotension between the groups, with statistical significance at the 10% (alpha = 0.1) level, one-tailed.

Results: One hundred forty patients were studied. Hypotension occurred in 43 (55%, 95% CI 43.4-66.4) preloaded and 44 (71%, 95% CI 58-81.8) unpreloaded subjects, a difference in incidence of 16% (95% CI 0.04-31.6), which was statistically significant. There were no significant differences in the severity, timing, or duration of hypotension; the dose requirement for ephedrine; or the clinical and biochemical status of neonates between the groups. The only difference seen was a lower mean base excess (-3.4, SD 2.81 mM-1) in the neonates of hypotensive mothers compared to neonates of nonhypotensive mothers (-2.4, SD 1.99 mM-1).

Conclusions: The study confirms that hypotension associated with spinal anesthesia for cesarean section cannot be eliminated by volume preloading in the supine wedged patient. The relatively small reduction in incidence of hypotension challenges our perception of the value of crystalloid preload. Though volume preload in the elective cesarean section is advocated, the requirement for a mandatory administration of a fixed volume before spinal anesthesia for urgent cases has been abandoned.

PubMed Disclaimer

Comment in

LinkOut - more resources