title: Using blood loss pictogram for visual blood loss estimation in cesarean section.
abstract: 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.
  
  
  METHODS
  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 allprofessions and clinical experience.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Anesthesiology, Charoenkrung Pracharak Hospital, Medical Service Department, Bangkok Metropolitan Administration, Bangkok, Thailand. phutchjirah@gmail.com
authors.forename: Phutchjirah
authors.initials: P
authors.lastname: Cheerranichanunth
authors.forename: Pattama
authors.initials: P
authors.lastname: Poolnoi
mesh_terms: D001296:Audiovisual Aids; D016063:Blood Loss, Surgical; D001810:Blood Volume; D001811:Blood Volume Determination / Q000379:methods*; D002585:Cesarean Section / Q000009:adverse effects*; D002983:Clinical Competence; D005260:Female; D006801:Humans; D006473:Postpartum Hemorrhage / Q000175:diagnosis* / Q000209:etiology; D011247:Pregnancy; D015203:Reproducibility of Results