Flow cytometric assessment of feto-maternal hemorrhage; a comparison with Betke-Kleihauer

Systematic Kleihauer-Betke Test after External Cephalic Version for Breech Presentation: Is It Useful?

The incidence of fetomaternal hemorrhage (FMH) after external cephalic version (ECV) has been poorly reported. In this study, we evaluated the frequency of FMH, diagnosed by positive Kleihauer–Betke test (KBT), after ECV attempt and then evaluate the relevance of its routine use after procedure. A total of 282 women with a term breech presentation and who had ECV attempt were recruited from January 2014 and December 2018. After ECV attempt, women were systematically screened for FMH using KBT. Data on ECV attempt, KBT results, perinatal and neonatal outcomes were collected and compared between women with positive (cases) and negative KBT (controls) after ECV. The success rate of ECV was 22.0% (62/282). Eight women (2.9%) experienced transient fetal heart rate (FHR) abnormalities after ECV. In five (1.8%) women, KBT was positive after ECV. Obstetrical management was modified for two of these five women due to continuous positivity of KBT at day 1 and day 7 controls after ECV attempt. A cesarean section was planned 7 days earlier due to persistent high FMH on day 7 (6 mL fetal blood) in one woman and the labor was induced for persistent high FMH on day 7 (20 mL fetal blood) for another woman. No newborns have signs of fetal anemia at birth and there was no significant difference in neonatal status between two groups. FMH after ECV attempt are rare, and no negative fetal or neonatal outcomes were observed when KBT was positive, even strongly (>5 mL fetal blood). It appears that systematic KBT after attempted ECV is probably not useful.

Guidance for Evaluation and Management of Blunt Abdominal Trauma in Pregnancy

Blunt abdominal trauma is the leading type of traumatic injury in pregnancy, with motor vehicle crashes, falls, and assault being the most common etiologies. Several adverse outcomes can occur in pregnancy, including placental abruption, preterm labor and preterm delivery, uterine rupture, and pelvic fracture. Understanding and integration of key anatomic and physiologic changes in pregnancy are key when evaluating a pregnant trauma patient. Pregnant women should be managed in a medical center with the ability to provide adequate care to both trauma patients-the pregnant woman and fetus. Multiple clinical providers are usually involved in the care of pregnant trauma patients, but obstetric providers should play a central role in the evaluation and management of a pregnant trauma patient given their unique training, knowledge, and clinical skills. An algorithm for management of trauma in pregnancy should be used at all sites caring for pregnant women. An alignment of policies within each system optimizes appropriate triage, integration of care, management, and monitoring of pregnant trauma patients and their fetuses. Ensuring effective protocols for prehospital and hospital treatment, as well as thorough training of involved health care providers, is essential in ensuring that optimal care is provided.

Fetomaternal Bleeding and Neonatal Hematocrit following Cesarean Delivery: Routine versus Transplacental Transection

Objective  To evaluate fetomaternal bleeding following routine cesarean delivery compared with cesarean delivery involving transplacental transection. Study Design  A prospective cohort study evaluating cesarean delivery in which the placenta was transected (cases) versus controls (placenta not transected) from January 2016 to April 2018. A maternal Kleihauer-Betke's (KB) test and newborn hematocrit were performed shortly after delivery. Results  The rate of a positive KB test was not significantly different between cases ( n  = 31) and controls ( n  = 61) (19 vs. 14%; odds ratio [OR]: 1.44; 95% confidence interval [CI]: 0.46-4.49; p  = 0.74). Median neonatal hematocrits were not different. However, the rate of newborn hematocrits <40% at delivery was higher in cases compared with controls (23 vs. 3%; OR: 8.90; 95% CI: 1.72-45.90; p  = 0.005). Conclusion  A cesarean requiring transplacental transection to accomplish delivery does not significantly increase the rate of fetomaternal bleeding but is associated with a higher likelihood of newborn hematocrit <40% at delivery.

Association of placental inflammation with fetomaternal hemorrhage and loss of placental mucin-1

BACKGROUND

Fetomaternal hemorrhage (FMH) poses an immediate risk to the fetus and, in case of Rhesus-immunization, to future pregnancies. Given that altered endothelial permeability is part of the pathophysiology of inflammation, in this study we investigated whether placental inflammatory processes like chorioamnionitis (ChoA) or preeclampsia (PE) lead to increased rates of FMH compared to the established risk factor of placenta previa (PP). Putative accompanying markers of trophoblastic damage were also explored.

METHODS

40 patients (14 PE; 6 ChoA; 9 PP; 11 normal controls) were evaluated for FMH using a flowcytometric test kit, which is able to quantify FMH of 0.06% fetal cells. Placental tissue samples were immunostained for human placental lactogen (hPL), human chorionic gonadotropin (hCG), and mucin-1 (MUC1). MUC1 was evaluated as a potential serum marker of FMH.

RESULTS

Patients with ChoA had a mean calculated FMH volume of 29 ml, compared to 4 ml in PE and 1 ml in PP and controls. MUC1 staining was reduced in PE and ChoA placenta samples, while elevated MUC1 serum concentration correlated positively with FMH.

CONCLUSION

Diseases of placental inflammation are associated with FMH. Placental MUC1 staining is reduced and serum concentrations are increased in cases of FMH.

Fetomaternal hemorrhage in women undergoing elective cesarean section

OBJECTIVE

To investigate the degree of fetomaternal hemorrhage (FMH) caused by elective cesarean section.

DESIGN

Descriptive study.

SETTINGS

University Hospitals in Copenhagen, Denmark.

POPULATION

Women scheduled for elective cesarean section, in the period September 2007 to January 2009, at the Department of Gynecology and Obstetrics, Hvidovre Hospital, University of Copenhagen, Denmark.

METHODS

Two maternal blood samples were taken, the first before cesarean section and the second immediately after. Both samples were analyzed at the Blood Bank, Rigshospitalet, Copenhagen, for the presence of fetal red blood cells (fRBCs) using flow cytometry. FMH associated with cesarean section was defined as the difference between the volumes of fRBCs in the two samples.

MAIN OUTCOME MEASURES

The frequency and volume of FMH caused by elective cesarean section.

RESULTS

207 women were included in the study. FMH was detected in 38 cases (18.4%). Of these, 22 women (10.6%) had FMH of less than 1 ml fRBCs, 13 women (6.3%) had FMH between 1 and 4 ml fRBCs, and three women (1.4%) had FMH above 4 ml fRBCs.

CONCLUSIONS

We found no evidence for recommending general screening for FMH in connection with elective cesarean section, provided guidelines such as the current Danish guidelines for Rhesus prophylaxis are followed.

Flowcytometric assessment of fetomaternal hemorrhage during external cephalic version at term

External cephalic version (ECV) at term is a safe procedure and reduces the incidence of cesarean sections for breech presentation. One of the known complications, however, is an ECV-related disruption of the placental barrier and a subsequent transfusion of fetal blood into maternal circulation. While the incidence of ECV-related fetomaternal hemorrhage (FMH) has been determined recently in a large trial using a manual Kleihauer-Betke test (KBT), questions remain on the amount of ECV-related FMH. KBT, which detects fetal red blood cells (RBC) on the basis of acidic resistance of fetal hemoglobin (HbF), is known to be a sensitive test, yet prone to procedural errors limiting its accuracy in quantifying FMH. In this study we investigated 50 patients for FMH before and after ECV, using a dual-color flow cytometric test kit with a lower limit of quantification of 0.05% fetal RBC in maternal peripheral blood. Three patients had a quantifiable increase of fetal RBC detected after ECV (0.06%; 0.08%; 0.1%). None of these subtle increments was predictable by ECV-related clinical parameters or translated into fetal compromise. Using a sensitive and accurate flow cytometric test method, our data provide further assurance to mothers on the safety of ECV at term.