Peripartum estimated blood loss: Effects of delivery mode

SMFM Abstracts S97 291 PERIPARTUM ESTIMATED BLOOD LOSS: EFFECTS OF PERINEAL LACERATION IRENE STAFFORD1, GARY DILDY1, STEVEN CLARK2, MICHAEL BELFORT2, 1Louisiana State University Medical Center at New Orleans, Obstetrics & Gynecology, New Orleans, Louisiana, 2St Mark’s Hospital, Maternal-Fetal Medicine, Salt Lake City, Utah OBJECTIVE: The purpose of our study is to examine trends in blood loss according to degree of perineal laceration, comparing visual estimated blood loss (vEBL) with calculated estimated blood loss (cEBL) in vaginal deliveries. STUDY DESIGN: Between January 1 and September 2 of 2005, there were 876 deliveries on the LSU obstetrical service at University Hospital. After excluding those with blood transfusions, 677 who had height/weight and preand post-delivery hematocrit (HCT) data were analyzed. Of the 446 women who underwent vaginal delivery, 290 had no lacerations (L0), 72 had first degree lacerations (L1), 78 had second degree lacerations (L2) and 6 had either a third or fourth degree lacerations (L3-4). vEBL was recorded in mL by the physician present at delivery. cEBL was derived by multiplying the calculated pregnancy blood volume (0.75 ! {[Maternal height in inches ! 50] + [Maternal weight in pounds ! 25]}) by percent of blood volume lost ({pre-delivery HCT – post-delivery HCT}/pre-delivery HCT). Statistitical analysis was accomplished using the Wilcoxon signed-rank test and the Kruskal-Wallis test with a P-value of less than .05 considered significant RESULTS: The median vEBL for L0, L1, L2, L3-4 was 200, 250, 300 and 350 mL respectively. The median cEBL for these groups was 519, 604, 764 and 932 mL respectively. Box plots in the figure illustrate 10, 25, 50, 75, and 90th percentile for each group. The median difference between vEBL and cEBL for L0, L1, L2, L3-4 was 259, 343, 460 and 582 mL respectively.

90th percentile. There were statistically significant differences between vEBL and cEBL for each category, as well as between each mode of delivery.

CONCLUSION: vEBL is underestimated for SVD, and even more so for OVD. These findings underscore the potential for unrecognized hemorrhagerelated morbidity in OVD and the importance of developing improved methods of calculating blood loss in clinical practice. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2006.10.318

CONCLUSION: This study demonstrates that the magnitude of underestimation of vEBL increased with the degree of perineal laceration. 0002-9378/$ - see front matter doi:10.1016/j.ajog.2006.10.317

292 PERIPARTUM ESTIMATED BLOOD LOSS: EFFECTS OF DELIVERY MODE IRENE STAFFORD1, GARY DILDY1, STEVEN CLARK2, MICHAEL BELFORT2, 1Louisiana State University Medical Center at New Orleans, Obstetrics & Gynecology, New Orleans, Louisiana, 2St Mark’s Hospital, Maternal-Fetal Medicine, Salt Lake City, Utah OBJECTIVE: Visual estimated blood loss (vEBL) is well known to be imprecise in clinical practice. Our objective is to compare vEBL with calculated estimated blood loss (cEBL) according to mode of delivery. STUDY DESIGN: Between January 1 and September 2 of 2005, the LSU obstetric service at University Hospital in New Orleans delivered 876 women. After excluding 36 with blood transfusion, there remained 677 with height/ weight, pre- and post-delivery hematocrit (HCT) data. 421 experienced spontaneous vaginal delivery (SVD), 25 operative vaginal delivery (OVD), and 231 cesarean delivery (CD). cEBL was derived by multiplying the calculated pregnancy blood volume (0.75 ! {[Maternal height in inches ! 50] C [Maternal weight in pounds ! 25]}) by percent of blood volume lost ({pre-delivery HCT – post-delivery HCT}/pre-delivery HCT). Statistical analysis was performed with the Kruskal-Wallis and Wilcoxon signed-rank tests, with P!0.05 considered significant. RESULTS: The mean vEBL was 250, 300, and 800 mL for SVD, OVD, and CD, respectively. The mean cEBL was 574, 728, and 818 mL for SVD, OVD, and CD, respectively. Box plots in the figure demonstrate the 10, 25, 50, 75 and

293 REFUSAL OF TREATMENT IN OBSTETRICS- A MATERNAL-FETAL CONFLICT IRIS OHEL1, AMALIA LEVY2, MOSHE MAZOR1, EYAL SHEINER1, 1Soroka University Medical Center, Beer-Sheva, Israel, 2Ben Gurion University of the Negev, Epidemiology and Health Services Evaluation, Beer-Sheva, Israel OBJECTIVE: Clinical studies about the necessity of standard obstetric interventions raise questions, on occasion making refusal of pregnant women to treatment a legitimate choice. The present study was aimed to characterize patients refusing medical treatment during pregnancy and delivery, and to examine whether refusal of treatment is associated with adverse perinatal outcome. STUDY DESIGN: A population-based study, comparing patients who refused and did not refuse medical intervention during pregnancy and delivery was conducted. Deliveries occurred between the years 1988-2002 in a tertiary medical center. RESULTS: Out of 165,962 deliveries, 1.1% (n=1898) were of patients refusing medical intervention. Patients refusing medical intervention tended to be older (30.5G5.0 vs. 28.4G5.9 years, P!0.001) and of higher parity (52.5% vs. 32.4% had more than 5 deliveries, P!0.001). Likewise, these women were more likely to have a previous cesarean delivery (CD), and previous adverse perinatal outcome as compared to the comparison group (65% vs. 12.3%, P!0.001; 11.4% vs. 4.2%, P!0.001; respectively). Mothers refusing treatment had higher rates of complications such as placental abruption (1.8% vs. 0.8%, P!0.001), preterm delivery (18.6% vs. 8.1%, P!0.001) and post-partum hemorrhage (0.8% vs. 0.4%, P=0.008). Parturients refusing medical treatment experienced significantly higher rates of adverse perinatal outcome including low Apgar scores (!7 at 1 and 5 minutes; 12.4% vs. 4.4%, P!0.001, and 1.9% vs. 0.6%, P!0.001; respectively). Moreover, higher rates of perinatal mortality in general, and intra-partum death in particular were documented among women refusing medical treatment (3.3% vs. 1.5%, P!0.001; 0.8% vs. 0.1%, P!0.001; respectively). Using a multiple logistic regression model, with perinatal mortality as the outcome variable, refusal of treatment was found as an independent risk factor for perinatal mortality (OR=1.5, 95% CI 1.1-2.0; P=0.010). CONCLUSION: Refusal of treatment is an independent risk factor for perinatal mortality 0002-9378/$ - see front matter doi:10.1016/j.ajog.2006.10.320