Accuracy of Blood Loss Estimation After Vaginal Delivery

Not Applicable

Completed

Conditions: Postpartum Hemorrhage

Interventions: Procedure: blood loss estimation

Registration Number: NCT00462839

Lead Sponsor: Northwestern University

Brief Summary: Post-partum hemorrhage (PPH) is defined as blood loss greater than 500 mL after vaginal delivery. Delayed diagnosis of PPH is a major cause of maternal morbidity and mortality. Obstetricians estimate blood loss at delivery by visual estimation of blood collected in the obstetric drapes. Blood is often mixed with urine and surgical sponges. The urine, blood, and sponges collect in a cone shaped plastic bag that is suspended from the perineum during delivery. Visual estimation of blood loss is insensitive in diagnosing PPH. In one study visual assessment of blood loss underestimated postpartum blood loss by 33% to 50% compared to an objective measurement of blood loss using photospectrometry. Other studies have shown that the magnitude of underestimation increases as the amount of blood loss is increased. A limitation of previous studies is that there is no "gold standard" for blood loss determination in the third stage of labor. Care providers (obstetricians, anesthesiologists, and labor \& delivery nurses) need to be able to accurately estimate blood loss in order to better care for mothers and prevent morbidity and mortality. It is unknown whether provider type or experience (obstetric and anesthesiology resident, fellow, attending physicians, and nurses) influences the accuracy of blood loss estimation, or whether blood loss estimation can be improved by providing graduated markings on the vaginal delivery drape.

Detailed Description: Packed red blood cells discarded by the blood bank will be mixed with normal saline to simulate whole blood with a hematocrit of 33%. A total of eight isolated study stations will be set up (study participants will only be able to visualize the vaginal delivery drape for one station at a time). The simulated blood will be mixed with urine and sponges and be placed in suspended blood collection drapes which are used during vaginal deliveries at Northwestern Memorial Hospital. Two types of drapes will be used: drapes without calibrated markings and drapes with calibrated markings. Calibrated volume markings will begin at 500 mL at 500 mL intervals to 2500 mL.

Study participants will be randomized to one of two groups. Randomization will occur in blocks depending on provider type. Group 1 will view the unmarked vaginal collection drapes first and Group 2 will view the collection drapes with the calibrated markings first. Both groups will analyze the initial four study stations in random order. At the completion of the four study stations, the group which evaluated the drapes without markings will cross over to view the stations with calibrated markings and the group that views uncalibrated drapes will then view the calibrated drapes.

Each study participant will view a station and write his/her estimation of blood loss on a data card. Study participants will NOT be allowed to change answers once they have been recorded.

Demographic data on study participants will include provider type, level of training/years of practice, and gender.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 106

Inclusion Criteria

Any anesthesia or obstetric attending or resident may participate provided that they have rotated through obstetrics/obstetric anesthesia.

Exclusion Criteria

Any provider that does not complete all of the stations will be excluded from analysis. Any participant who chooses to withdraw from the study will also be excluded from the analysis.

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Non-calibrated drapes viewed first	blood loss estimation	Standard vaginal delivery drape (non-calibrated) was shown to caregiver who was asked to estimate amount of blood. These same individuals were then crossed over and shown calibrated delivery drapes and asked to estimate the amount of blood they contained.
Calibrated drapes viewed first	blood loss estimation	Caregivers were shown calibrated drape demonstrating level of blood and asked to estimate amount of blood in collection bag. These same individuals were then crossed over and shown non-calibrated drapes and asked to estimate the amount of blood they contained.

Primary Outcome Measures

Name	Time	Method
Difference in Actual Blood Volume and Estimated Blood Volume in Milliliters.	1 hour	Two types of drapes were used: drapes with and without volume calibrations. Calibrated drapes had volume markings beginning at 500ml with 500ml increments to a total of 2500ml. The participants were asked to estimate the volume contained in the bag and the difference in milliliters between the estimate and actual volume was calculated.

Secondary Outcome Measures

Name	Time	Method
Level of Training	1 hour
Number of Years of Clinical Experience Providing Patient Care Requiring Blood Loss Estimation.	1 hour
Number and Type of Care Providers Assigned to Study Arms.	1 hour