Andrew P. Mackenzie

The Closure of Iatrogenic Membrane Defects after Amniocentesis and Endoscopic Intrauterine Procedures

Objective: To describe a new technique for wound closure after endoscopic intrauterine procedures which prevents amniotic fluid leakage after the procedure. Study Design: This is an observational study which reviews a new technique under an IRB-approved protocol. The rationale for this study was the increasing frequency of intrauterine endoscopic procedures. The most common complication of these procedures is persistent leakage of amniotic fluid from puncture sites, which can result in preterm labor and preterm delivery. Thus, these procedures carry a high morbidity rate that may overcome the benefit of the intervention. We have employed a new technique, which has successfully prevented amniotic fluid leakage following the procedure. The instruments used for the endoscopic procedures were no larger than 3.5 mm for all cases. A sealant of platelets was rapidly injected followed by injection of fibrin glue and powdered collagen slurry at each puncture site. Sonography for modified AFI, clinical examination for nitrazine and ferning, and pad count were performed after each procedure at three intervals: immediately after the procedure, 24 h and 48 h. Results: Eight patients undergoing an endoscopic intrauterine procedure (either cord ligation for twin-twin transfusion syndrome or sealing of ruptured membranes after amniocentesis) were included. All patients were treated between 18 and 24 weeks of gestation. Sonography, clinical examination and pad count revealed no evidence of amniotic fluid leakage either intra-abdominally or vaginally in any of the patients. There was 1 patient who ruptured membranes 12 h after the procedure due to severe vomiting. Another patient elected to terminate the pregnancy 48 h after the procedure without evidence of leakage. The remaining patients continued for 8 weeks or more without fluid leakage. Conclusion: The technique described, immediate sealing of puncture wounds following endoscopic intrauterine procedures, is effective in preventing amniotic fluid loss after the procedure.

Debate Preparation/Participation: An Active, Effective Learning Tool

Background: Passive educational techniques (such as lectures) are thought to be less productive than active learning. Purpose: We examined whether preparing for and participating in a debate would be an effective, active way to learn about a controversial topic. Methods: We compared quiz performance in residents who attended a lecture to residents who prepared for/participated in a debate. Twelve residents each participated in one lecture session and one debate session. Learning was evaluated via a quiz. Quizzes were given twice: before the debate/lecture and 1 week after the debate/lecture. Quiz scores were compared using repeated measures analysis of variance, with a p value of < .05 considered significant. A survey evaluating the usefulness of debating was given to all participants. Results: There was a statistically significant difference in the pretest mean quiz score between the debate and lecture groups: 78.3% and 52.5%, respectively ( p = .02). Similarly, on posttest quizzes, the average debater scored 85.8%, versus 61.7% for the lecture group ( p = .003). Although no one in the debate group scored lower on a follow-up quiz, 3 residents in the lecture group did worse on follow-up. Conclusions: When learning about a controversial topic, residents who prepared for/participated in a debate achieved higher quiz scores and were better at retaining information than those who attended a lecture. When faced with teaching a controversial topic, organizing a debate may be more effective than giving a lecture.

Endoscopic closure of fetal membrane defects: comparing iatrogenic versus spontaneous rupture cases

OBJECTIVE Currently, physicians manage preterm premature rupture of membranes (PPROM) by expectant management or termination of the gestation. A therapy aimed at sealing membranes would be optimal to maintain the pregnancy and achieve a normal neonate. Our objective was to compare an endoscopic technique for intrauterine closure of fetal membrane defects after both iatrogenic and spontaneous rupture of membranes. METHODS Our technique was performed on four patients experiencing PPROM spontaneously and four patients after genetic amniocentesis. Intrauterine endoscopy allowed direct visualization of membrane defects. Rapid sequential injections of platelets, fibrin glue and powdered collagen slurry were administered at the site of the defect and of trocar placement. Sonography for amniotic fluid index, nitrazine and fern testing and pad count were performed after each procedure at three intervals: immediately post-procedure, and after 24 and 48 h. RESULTS Eight patients underwent endoscopic intrauterine sealing of ruptured membranes between 16 and 24 weeks of gestation: four were spontaneous ruptures and four were ruptures post-amniocentesis. In the post-amniocentesis group, three patients delivered viable infants at 26, 32 and 34 weeks. In one patient, the membranes ruptured again 12 h after the sealing procedure and she decided to undergo termination of pregnancy. Of the four spontaneous rupture patients, two experienced preterm labor and delivery within 2 days of the procedure. One patient was diagnosed with fetal demise 12 h post-procedure, and one patient delivered a neonate at 31 weeks of gestation with severe respiratory distress syndrome. CONCLUSIONS This technique for sealing ruptured membranes is effective after amniocentesis, but may not be of benefit with spontaneous rupture.

Glutathione peroxidase levels throughout normal pregnancy and in pre-eclampsia

Objective: Evidence suggests that hemoglobin, in addition to its function as a carrier of oxygen, also serves to transport nitric oxide, as S-nitroso cysteine, from the lungs to the peripheral circulation, where it can be released. Glutathione peroxidase, besides being an important antioxidant, is known to catalyze the release of nitric oxide from smaller carrier molecules, and may play a role in the distribution of nitric oxide throughout the body. In light of these findings, we sought to determine whether glutathione peroxidase levels differed throughout gestation, and specifically between pre-eclamptic and normal women. Methods: A nested case-control study of women receiving routine prenatal care was conducted. Pre-eclampsia was defined by a blood pressure of at least 140 mmHg systolic and/or 90 mmHg diastolic as well as proteinuria > 300 mg/24 h or > 2+ by dipstick, both occurring on two occasions at least 6 h apart. Blood was collected in heparinized tubes and was then centrifuged in a clinical centrifuge for 10 min. Plasma was frozen promptly at -80°C for later enzyme-linked immunosorbent assay (ELISA), with which plasma glutathione peroxidase was determined. Results: The maternal demographics of the pre-eclamptic and non-pre-eclamptic study groups did not significantly vary with respect to mean maternal age, gravidity, parity and gestational age at the time of delivery. The median maternal ages were 33 and 34 years, and the median gestational ages at the time of birth were 37.5 and 38.1 weeks, respectively. In evaluating the glutathione peroxidase levels of all patients across the three trimesters, we found that there was essentially no difference in mean levels (83.7, 81.0 and 89.5 ng/ml, respectively). There was no difference between the pre-eclamptic and non-pre-eclamptic patients, again stratified by trimester. A linear regression analysis indicated that the plasma glutathione peroxidase concentration did not correlate with gestational age or the presence of pre-eclampsia. Conclusions: Plasma glutathione peroxidase expression is similar across all trimesters. There is no change in the glutathione peroxidase levels in pre-eclamptic patients.

Combined sonographic and endoscopic umbilical cord occlusion in twin and triplet gestations.

Abstract Objective: To review our experience with a minimally invasive technique for umbilical cord occlusion as a method of selective feticide in monochorionic sets. Study design: Umbilical cord occlusion was completed using 3 mm bipolar cautery under ultrasound guidance (3D/4D, n=6; 2D, n=6) with pre and post ligation endoscopic evaluation. Results: 12 cases of monochorionic sets where selective feticide was performed were identified during the period 2000 to present. There were four triplet and eight twin gestations in the study cohort. Median interval from intervention to delivery was 16 weeks (range, 5–19). All co-twins survived the procedure and 15 of 16 were delivered after 33 weeks. Conclusions: Umbilical cord occlusion in monochorionic sets can be accomplished in a minimally invasive manner with combined endoscopic and ultrasound guidance in both twin and triplet pregnancies.

Increased rates of chorioamnionitis with extra-amniotic saline infusion method of labor induction.

OBJECTIVE: Extra-amniotic saline infusion has been shown to be equal to or more efficacious than misoprostol, laminaria, dinoprostone, and prostaglandin estradiol for cervical ripening and labor induction. Because of the introduction of a foreign body into the uterus, extra-amniotic saline infusion may potentially cause increased rates of chorioamnionitis. This study examines the risk of chorioamnionitis with extra-amniotic saline infusion compared with other methods of induction and spontaneous labor. METHODS: A retrospective analysis was performed based on deliveries at Bellevue Hospital Center, a tertiary-care facility, from August 2000 to December 2002. Three groups were identified: extra-amniotic saline infusion, other methods of induction, and spontaneous labor. Differences in chorioamnionitis rates were analyzed by using analysis of variance and multivariable logistic regression as appropriate. RESULTS: There were 625 charts evaluated: 171 extra-amniotic saline infusion, 190 other, and 264 with spontaneous labor. The rates of chorioamnionitis were 26.9%, 17.9%, and 13.3%, respectively. After adjusting for confounding variables, such as instrumentation, length of rupture, and number of exams, subjects who were induced with extra-amniotic saline infusion were significantly more likely to develop chorioamnionitis (relative risk = 2.2; 95% confidence interval 1.4, 4.0; P = .006). CONCLUSION: Extra-amniotic saline infusion may be associated with a greater risk of chorioamnionitis when compared with other methods of labor induction. Given the increased risk of chorioamnionitis associated with extra-amniotic saline infusion, its use should be in the context of a careful assessment of the risks and benefits of various methods of labor induction. LEVEL OF EVIDENCE: II-2

Four-dimensional real-time sonographically guided cauterization of the umbilical cord in a case of twin-twin transfusion syndrome.

In the past decade, three-dimensional (3D) sonographic technology has matured from a static imaging modality to near-real-time imaging. One of the more notable improvements in this technology has been the speed with which the imaged volume is acquired and displayed. This has enabled the birth of the near-real-time or four-dimensional (4D) sonographic concept. Using the 4D feature of the current 3D sonography machines allows us to follow moving structures, such as fetal motion, in almost real time. Shortly after the emergence of 3D and 4D technology as a clinical imaging tool, its use in guiding needles into structures was explored by other investigators. We present a case in which we used the 4D feature of our sonographic equipment to follow the course and motion of an instrument inserted into the uterus to occlude the umbilical cord of a fetus in a case of twin-twin transfusion syndrome.