Using Blood Loss Pictogram for Visual Blood Loss Estimation in Cesarean Section
Phutchjirah Cheerranichanunth MD*, Pattama Poolnoi RN*
Affiliation : * Department of Anesthesiology, Charoenkrung Pracharak Hospital, Medical Service Department, Bangkok Metropolitan Administration, Bangkok, Thailand
Objective : To determine whether using pictogram can improve visual estimation of blood loss in a mock cesarean setting and
whether profession and clinical experience influence the accuracy of blood loss estimation.
Material and Method: Photographs of measured blood volume absorbed in different percentage of surface area of common
surgical materials were taken and arranged in the table of pictogram. Pictures of seven cesarean scenarios were set with
known blood volumes (20, 35, 60, 100, 350, 400, and 1200 ml) in different surgical materials. Forty-nine participants from
four professions had to view all seven pictures and quantitatively estimate blood volume pre-post using the pictogram.
Percent error of estimated blood loss was analyzed.
Results : Before using the pictogram, tendency of underestimation, overestimation and accurate assessment in lower and
higher blood loss volumes were 43.4%, 25.7%, and 30.9% respectively. There was a trend in overestimating blood loss at
the lower volumes and underestimating or accurate estimating blood loss at higher volumes. Profession affected the accuracy
in estimation of some small blood loss volumes but clinical experience had no influence. After using the pictogram, accurate
estimation increased significantly from 30.9% to 61.8%. No difference in ability to determine blood loss in all professions and
clinical experience.
Conclusion : Estimated blood loss pictogram is a simple tool, easy to use for initial evaluation of blood loss in cesareans and
can improve the accuracy of visual blood loss assessment significantly.
Keywords : Blood loss pictogram, Visual assessment, Cesarean section, Blood loss estimation
