Faculty Bibliography

BACKGROUND: The rising cesarean birth rate has drawn attention to risks associated with repeat cesarean birth. Prevention of adhesions with adhesion barriers has been promoted as a way to decrease operative difficulty. However, robust data demonstrating effectiveness of such interventions are lacking. OBJECTIVE: We report data from a multicenter trial designed to evaluate the short-term safety and effectiveness of a modified sodium hyaluronic acid (HA)-carboxymethylcellulose (CMC) absorbable adhesion barrier for reduction of adhesions following cesarean delivery. STUDY DESIGN: Patients who underwent primary or repeat cesarean delivery were included in this multicenter, single-blinded (patient), randomized controlled trial. Patients were randomized into either HA-CMC (N = 380) or no treatment (N = 373). No other modifications to their treatment were part of the protocol. Short-term safety data were collected following randomization. The location and density of adhesions (primary outcome) were assessed at their subsequent delivery using a validated tool, which can also be used to derive an adhesion score that ranges from 0-12. RESULTS: No differences in baseline characteristics, postoperative course, or incidence of complications between the groups following randomization were noted. Eighty patients from the HA-CMC group and 92 controls returned for subsequent deliveries. Adhesions in any location were reported in 75.6% of the HA-CMC group and 75.9% of the controls (P = .99). There was no significant difference in the median adhesion score; 2 (range 0-10) for the HA-CMC group vs 2 (range 0-8) for the control group (P = .65). One third of the HA-CMC patients met the definition for severe adhesions (adhesion score >4) compared to 15.5% in the control group (P = .052). There were no significant differences in the time from incision to delivery (P = .56). Uterine dehiscence in the next pregnancy was reported in 2 patients in HA-CMC group vs 1 in the control group (P = .60). CONCLUSION: Although we did not identify any short-term safety concerns, HA-CMC adhesion barrier applied at cesarean delivery did not reduce adhesion formation at the subsequent cesarean delivery.

BACKGROUND:Fetal growth restriction (FGR) is associated with adverse outcomes extending from fetal to adult life, and thus, constitutes a major health care challenge. Fetuses with progressive growth restriction show increasing impedance in the umbilical artery flow, which may become absent during end-diastole. Absent end-diastolic flow (AEDF) is associated with adverse perinatal outcomes including stillbirths and perinatal asphyxia. Placentas from such pregnancies demonstrate deficient fetoplacental vascular branching. Current evidence, moreover, indicates an antiangiogenic state in maternal circulation in several pregnancy complications including preeclampsia, small-for-gestational-age births, fetal death, and preterm labor. The angiogenic mediators in maternal circulation are predominantly of placental origin. Information, however, on the role of specific proangiogenic and antiangiogenic mechanisms operating at the placental level remains limited. Elucidation of these placenta-specific angiogenic mechanisms will not only extend our understanding of the causal pathway for restricted fetal growth but may also lead to the development of biomarkers that may allow early recognition of FGR. OBJECTIVE:We sought to test the hypothesis that fetoplacental angiogenic gene expression is altered in pregnancies complicated with FGR and umbilical artery Doppler AEDF. STUDY DESIGN/METHODS:Placental samples were collected from FGR pregnancies complicated with umbilical artery Doppler AEDF (study group, n = 7), and from uncomplicated pregnancies (control group, n = 7), all delivered by cesarean during the last trimester of pregnancy. Angiogenic oligonucleotide microarray analysis was performed and was corroborated by quantitative real-time polymerase chain reaction, Western blot analysis, and immunohistochemistry. The Student t test with Bonferroni correction was used with P < .05 considered statistically significant. Independent groups t test was used to analyze the immunostain intensity scores with a P < .05 considered statistically significant. RESULTS:Our microarray results showed that among several differentially expressed angiogenic genes in the growth-restricted group, only the down-regulation of neuropilin (NRP)-1 was most significant (P < .0007). Quantitative real-time polymerase chain reaction confirmed a significantly lower NRP-1 gene expression in the FGR group than in the control group (mean ± SD (ˆ)cycle threshold: 0.624 ± 0.55 and 1.325 ± 0.84, respectively, P = .04). Western blot validated significantly lower NRP-1 protein expression in the FGR group than in the control group (mean ± SD NRP-1/β-actin ratio: 0.13 ± 0.04 and 0.34 ± 0.05, respectively, P < .001). Finally, immunohistochemistry of placental villi further corroborated a significantly decreased expression of NRP-1 in the FGR group (P = .006). CONCLUSION/CONCLUSIONS:The study demonstrated significant down-regulation of placental NRP-1 expression in FGR pregnancies complicated with AEDF in umbilical artery. As NRP-1 is known to promote sprouting angiogenesis, its down-regulation may be involved in the deficient vascular branching observed in FGR placentas suggesting the presence of an antiangiogenic state. Further studies may elucidate such a causal role and may lead to the development of novel diagnostic and therapeutic tools.

INTRODUCTION/BACKGROUND:Postpartum hemorrhage is a major cause of maternal morbidity and mortality throughout the world and uterine atony is the leading cause of postpartum hemorrhage. The B-Lynch brace suture is a fertility-sparing approach to treating intractable uterine atony at the time of cesarean delivery. However, many obstetricians lack confidence to perform this procedure, which they may not have performed during residency. In order to train all residents to perform the B-Lynch brace suture, we developed a realistic model by using a flank steak to imitate a gravid uterus. METHODS:A convenience sample of obstetrics-gynecology faculty and residents at different levels of training at a single large hospital participated in this pilot project. Each physician reported self-perceived understanding of and confidence in performing the B-Lynch procedure before and immediately after practicing the technique using the flank-steak model, via a Likert-type survey (scale 1  =  low, 5  =  high). A Wilcoxon matched-pairs signed rank test was used to compare the before and after responses. RESULTS:Thirty-four participants completed the flank-steak model training and pretraining/posttraining surveys. The median score (range) for self-perceived understanding was 4 (2-5) and increased to 5 (4-5) (P < .01) after exposure to the training model. The confidence scores rose from 3 (1-5) to 5 (4-5) (P < .01) after training. CONCLUSION/CONCLUSIONS:The flank-steak model for teaching the B-Lynch suture significantly improved resident and faculty self-perceived understanding of and confidence in performing this procedure, which is otherwise rarely practiced in residency.