Materials and Methods

This study was approved by Northwestern University’s Institutional Review Board. The didactic program was initiated as a quality initiative at Northwestern Memorial Hospital to improve the recognition of postpartum hemorrhage. All labor and delivery unit providers, which included obstetric and anesthesiology attending and resident physicians, and nurses participated in the educational program. Participation in the program, as part of the quality initiative, was mandatory; participants gave consent to allow their results to be used for the study.

The training program was divided into 2 phases. A live version of the training program took place during a 1-week period in March 2008 in 2 adjacent rooms on the labor and delivery unit. Informed consent was obtained before live participation. With the use of expired packed red blood cells that had been reconstituted to a hematocrit of 33%, the study investigators poured measured blood volumes onto each study station. The cylinders that were used to measure the blood volumes had volumetric accuracy of ±5%. Study stations consisted of 3 small-volume stations (laparotomy sponge, perineal pad, and large under-the-buttocks pad) and 2 large-volume stations, which simulated postpartum hemorrhage (under-the-buttocks vaginal delivery drape and hemorrhage onto a bed with a mannequin; Figure 1 ; Table 1 ). Participants rotated to each of the 5 stations sequentially and wrote the volume estimate for each station on a data sheet, which was collected immediately after the estimations were made. Participants were then told the actual volumes at each station.

Photographs of the 5 stations

A , Laparotomy sponge; B , perineal pad; C , large blue under-the-buttocks pad; D , vaginal delivery drape; E , blood spill on a mannequin on a labor and delivery bed.

Toledo. Effect of education in blood-loss estimation scenarios. Am J Obstet Gynecol 2010.

After the pretest, a member of the investigational team reviewed a slide presentation with the participant that included the definition and risk factors for postpartum hemorrhage, the signs and symptoms of maternal hemorrhage, tools for estimating blood-loss, and the postpartum hemorrhage protocol that had been developed at Northwestern Memorial Hospital. The blood-loss estimation section of the didactic session consisted of photographs of varying amounts of blood loss (30, 100, 250, 500, and 1000 mL) on materials that were used in labor and delivery (eg, a laparotomy sponge). For comparison purposes, a given volume of blood was compared with an equal volume of liquid in common containers, such as a medicine cup, Dixie cup, half pint of milk, a pint of ice cream, or a 1-liter water bottle. A list of the saturation capacity for gauze sponges and laparotomy sponges was shown, as were estimates for floor blood spills of varying diameters and tools for estimating blood loss on a delivery bed. After the didactic session, a 5-station posttest was administered in a second room. The stations were the same as the pretest (ie, both low-volume and high-volume stations); however, the volumes of blood that were used at each station were varied from the pretest. Posttest volumes also were varied throughout the week by 3 sets of volumes.

Providers who did not participate in the live training completed a web-based online version of the training program during a 1-week period in May 2008. A written electronic script of the consent form was provided before the training. Participants completed a pretest in which they were asked to estimate blood loss in 5 photographs of the pretest stations that had been used in the live sessions. The stations were shown sequentially, and volume estimation was required to progress to the next station. After the pretest, the volumes for each of the stations were revealed. The participants were required to advance through the same didactic materials concerning postpartum hemorrhage and blood-loss estimation techniques in the slide presentation that had been presented at the live sessions. Finally, participants were asked to estimate blood loss from photographs of 1 of the posttest station sets that had been used during the live training (set 3).

The primary outcome was the accuracy of blood-loss estimation in the pretest compared with the posttest. Blood volume estimates were converted to percentages of the correct amounts for each station (eg, an estimate of 300 mL for a 200-mL blood loss was considered a 50% error). Participant characteristics that were collected included provider type, level of training, years of clinical experience, and previous formal training in blood-loss estimation. Comparisons of pretest to posttest estimates were made with the Wilcoxon signed-rank test; comparisons of live vs web-based training and individual station comparisons were made with the Mann-Whitney U test. Comparison of posttest results, which were stratified by live and web-based training, used only posttest data from volume set 3 of the live training, because these were the volumes that were used for the web-based posttest. Participant characteristics (provider type, level of training, number of years of experience, previous formal blood-loss estimation training) were compared between live and web-based training with a χ ² statistic. The effects of participant characteristics on the accuracy of blood-loss estimation were compared with the use of the Kruskal-Wallis H test. All tests were 2 tailed. A probability value of < .05 was used to reject the null hypothesis. Statistical analyses were performed with SPSS software (version 16.0.2; SPSS, Inc, Chicago, IL).