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The accuracy of blood loss estimation after simulated vaginal delivery
Paloma Toledo1, Robert J McCarthy, Bradley J Hewlett
1Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA.
Background:
Visual blood loss estimation often underestimates blood loss. In this study we sought to determine the effect of calibrated drape markings on blood loss estimation in a simulated vaginal delivery.
Methods:
Subjects were randomized to estimate simulated blood loss (300, 500, 1000, and 2000 mL) in calibrated or noncalibrated vaginal delivery drapes and then crossover.
Results:
Visual blood loss estimation with noncalibrated drapes underestimated blood loss, with worsening accuracy at larger volumes (16% error at 300 mL to 41% at 2000 mL). The calibrated drape error was <15% at all volumes.
Conclusions:
Calibrated vaginal delivery drapes improve blood loss estimation.
