Proning modus operandi in pregnancies complicated by acute respiratory distress syndrome secondary to COVID-19

INTRODUCTION

Prone positioning has been widely utilized in ARDS management before and during the COVID-19 pandemic due to its demonstrated mortality benefits. In pregnancy, proning requires careful attention to often overlooked physiologic changes in pregnancy and additional technical challenges accompanying a gravid abdomen. The purpose of this manuscript is to demonstrate a proning technique that was successfully used at our institution to avoid premature delivery of the fetus while improving maternal outcomes. All technical challenges are addressed in the instructional videos using a pregnant model with twin gestation at 32 weeks.

METHODS

We reviewed all the patients' charts with positive SARS-CoV-2 from March 2020 until July 2020 and identified those who developed ARDS. Subsequently, we identified four patients that were proned during the antepartum period. We described their clinical course, including the change in ventilatory parameters in relationship with proning timing. Stepwise instructions for self-proning and proning in mechanically ventilated patients are illustrated in video format.

RESULTS

During the study period, we identified 100 pregnant patients with SARS-CoV-2 infection. Mechanical ventilation was required in 8 of these patients. In four cases, proning was performed during the antepartum period. We were able to improve the P/F ratio while decreasing FiO₂ and avoiding iatrogenic preterm delivery. Except for one case, where the patient self-extubated and required emergent delivery, all patients were successfully extubated, followed for prenatal care, and delivered for usual obstetric indications.

CONCLUSION

Proning remains a well-proven intervention in ARDS and should be considered in pregnant women when indicated. We recognize that proning might not be effective in all cases. However, proning positioning is an option to improve oxygenation in patients with severe hypoxemia when the next consideration is delivery of a premature infant or maternal cannulation for extracorporeal membrane oxygenation.

Efficacy of long-term indomethacin therapy in prolonging pregnancy after fetoscopic laser surgery for twin-to-twin transfusion syndrome: a collaborative cohort study

OBJECTIVE

To evaluate the efficacy of long-term indomethacin therapy (LIT) in prolonging pregnancy and reducing spontaneous preterm birth (PTB) in patients undergoing fetoscopic laser surgery (FLS) for the management of twin-to-twin transfusion syndrome (TTTS).

DESIGN

Retrospective cohort study of prospectively collected data.

SETTING

Collaborative multicentre study.

POPULATION

Five hundred and fifty-seven consecutive TTTS cases that underwent FLS.

METHODS

Long-term indomethacin therapy was defined as indomethacin use for at least 48 hours. Log-binomial regression was used to estimate the relative risk of PTB in the LIT group compared with a non-LIT group. Cox regression was used to evaluate the association between LIT use and FLS-to-delivery survival.

MAIN OUTCOME MEASURES

Gestational age (GA) at delivery.

RESULTS

Among the 411 pregnancies included, a total of 180 patients (43.8%) received LIT after FLS and 231 patients (56.2%) did not. Median GA at fetal intervention did not differ between groups (20.4 weeks). Median GA at delivery was significantly higher in the LIT group (33.6 weeks) compared with the non-LIT group (31.1 weeks; P < 0.001). FLS-to-delivery interval was significantly longer in the LIT group (P < 0.001). The risks of PTB before 34, 32, 28 and 26 weeks of gestation were all significantly lower in the LIT group compared with the non-LIT group (relative risks 0.69, 0.51, 0.37 and 0.18, respectively). The number needed to treat with LIT to prevent one PTB before 32 weeks of gestation was four, and to prevent one PTB before 34 weeks was five.

CONCLUSION

Long-term indomethacin after FLS for TTTS was found to be associated with prolongation of pregnancy and reduced risk for PTB.

TWEETABLE ABSTRACT

Long-term indomethacin used after fetoscopic laser surgery for twin-to-twin transfusion syndrome is effective in prolonging pregnancy and reducing the risk for preterm birth; especially extreme preterm birth.

Antenatal Fetal Adrenal Measurements at 22 to 30 Weeks' Gestation, Fetal Growth Restriction, and Perinatal Morbidity

OBJECTIVE

Our objective was to test the association of fetal adrenal size with perinatal morbidity among fetuses with fetal growth restriction (FGR; estimated fetal weight [EFW] < 10th percentile).

STUDY DESIGN

This was a secondary analysis of the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be (nuMoM2b) adrenal study, which measured fetal adrenal gland size at 22 to 30 weeks' gestation. We analyzed the transverse adrenal area (TAA) and fetal zone area (absolute measurements and corrected for fetal size) and the ratio of the fetal zone area to the total transverse area using a composite perinatal outcome of stillbirth, neonatal intensive care unit admission, respiratory distress syndrome, necrotizing enterocolitis, retinopathy of prematurity, sepsis, mechanical ventilation, seizure, or death. Among fetuses with FGR, adrenal measurements were compared between those that did and did not experience the composite perinatal outcome.

RESULTS

There were 1,709 eligible neonates. Seven percent (n = 120) were diagnosed with FGR at the time of adrenal measurement, and 14.7% (n = 251) experienced perinatal morbidity. EFW-corrected and absolute adrenal measurements were similar among fetuses with and without FGR as well as among those who did and did not experience morbidity. The area under the curve for corrected TAA was 0.52 (95% confidence interval 0.38-0.67).

CONCLUSION

In our cohort, adrenal size was not associated with risk of morbidity among fetuses with FGR.

Clinical Outcomes of Pregnant and Postpartum Extracorporeal Membrane Oxygenation Patients

BACKGROUND

The use of extracorporeal membrane oxygenation (ECMO) as a rescue therapy for cardiopulmonary failure is expanding in critical care medicine. In this case series, we describe the clinical outcomes of 21 consecutive pregnant or postpartum patients that required venovenous (VV) or venoarterial (VA) ECMO. Our objective was to characterize maternal and fetal survival in peripartum ECMO and better understand ECMO-related complications that occur in this unique patient population.

METHODS

Between January 2009 and June 2019, all pregnant and postpartum patients treated with ECMO for respiratory or circulatory failure at a single quaternary referral center were identified. For all patients, indications for ECMO, maternal and neonatal outcomes, details of ECMO support, and anticoagulation and bleeding complications were collected.

RESULTS

Twenty-one obstetric patients were treated with ECMO over 10 years. Thirteen patients were treated with VV ECMO and 8 patients were treated with VA ECMO. Six patients were pregnant at the time of cannulation and 3 patients delivered while on ECMO; all 6 maternal and infant dyads survived to hospital discharge. The median gestational age at cannulation was 28 weeks (interquartile range [IQR], 24-31). In the postpartum cohort, ECMO initiation ranged from immediately after delivery up to 46 days postpartum. Fifteen women survived (72%). Major bleeding complications requiring surgical intervention were observed in 7 patients (33.3%). Two patients on VV ECMO required bilateral orthotopic lung transplantation and 1 patient on VA ECMO required orthotopic heart transplantation to wean from ECMO.

CONCLUSIONS

Survival for mother and neonate are excellent with peripartum ECMO in a high-volume ECMO center. Neonatal and maternal survival was 100% when ECMO was used in the late second or early third trimester. Based on these results, ECMO remains an important treatment option for peripartum patients with cardiopulmonary failure.

Surgical advances in the management of placenta accreta spectrum: establishing new expectations for operative blood loss

OBJECTIVE

To evaluate whether the implementation of our surgical approach, referred to in the text as Linear Cutter Vessel Sealing System (LCVSS) technique, will improve perioperative outcomes in patients with placenta accreta spectrum (PAS), specifically by reducing blood loss and blood transfusion rates at the time of cesarean hysterectomy (C-HYST). The LCVSS technique integrates the following: (1) hysterotomy performed using the Linear Cutter, (2) no placental manipulation, (3) cauterization of anatomically prominent vascular anastomosis using the handheld vessel sealing system, and (4) completion of bladder dissection until the cervico-vaginal junction before ligation and division of uterine arteries.

MATERIALS AND METHODS

This is a retrospective cohort study that analyzed perioperative outcomes in patients undergoing C-HYST for PAS at a tertiary care center from 1 July 2014 to 1 December 2019. Comparisons were performed between cases managed with the use of the LCVSS technique (designated as LCVSS cohort) and those managed without the use of the LCVSS technique (designated as no technique cohort). The primary outcomes were cumulative blood loss (CBL) and total perioperative blood transfusion of ≥4 and ≥6 units of PRBCs. The secondary outcomes were intra- and postoperative complications. Continuous and categorical variables were compared according to the sample size and distribution. Binary logistic regression analysis was performed to predict confounders for blood transfusion of ≥4 units of PRBCs.

RESULTS

A total of 69 prenatally diagnosed PAS cases underwent C-HYST at the time of delivery. Forty-four cases that were performed using the LCVSS technique comprised the LCVSS cohort. The remaining 25 were marked as no technique cohort. CBL was significantly lower in the LCVSS cohort (1124 ml [300-4100] vs 3500 ml [650-10600]; p < .001). The rate of urinary tract injuries was similar (16%). The rate of postoperative complications and reoperation for intra-abdominal bleeding were lower but not significantly different in LCVSS cohort (9 vs 20% and 0 vs 8%, p = .26 and p = .12, respectively). There were no differences in neonatal outcomes.

CONCLUSION

Implementation of this advanced surgical approach for PAS management resulted in reduced blood loss and blood transfusion rates in comparison with no technique cohort.

An initiative to evaluate the safety of maternal bonding in patients with SARS-CoV-2 infection

BACKGROUND

In the last two decades, the world faced three epidemics caused by novel coronaviruses, namely, SARS-CoV in 2002, MERS-CoV in 2012, and the ongoing SARS-CoV-2 that started in late 2019. Despite a growing understanding of SARS-CoV-2 virology, epidemiology, and clinical management strategies, other aspects, such as mode of delivery, vertical transmission, and maternal bonding, remain controversial. The question we faced upon the decision to separate the neonates of SARS-CoV-2 positive mother is whether we follow the principle of "do no harm"?

METHODS

This is a quality improvement project that analyzed all cases of SARS-CoV-2 positive pregnancies that delivered at a major health care system from March 1, 2020 to June, 1 2020. The article was prepared following Standards for Quality Improvement Reporting Excellence (SQUIRE) 2.0 guidelines. Data were prospectively collected and entered into the Research Electronic Data Capture (REDCap). Maternal bonding was defined by events such as rooming-in, skin to skin contact (STSC), and breastfeeding. Descriptive analysis was performed using the same software platform.

INTERVENTION

We compared neonatal transmission rates between those neonates who experienced bonding versus those who were separated.

RESULTS

A total of 1989 women were screened for SARS-CoV-2, from which 86 tested positive. Out of 31 analyzed pregnancies, five women (16%) were admitted to ICU and required mechanical ventilation. From the remaining 26 (84%), 17 (65%) opted for rooming-in, 12 (46%) for STSC, and 16 (61%) fed the infants with breastmilk (11 direct breastfeedings and five pumped the breast milk). All neonatal tests for SARS-CoV-2 returned negative.

CONCLUSION

Our results have illustrated that maternal bonding appears safe in neonates born to mothers that are SARS-CoV-2 positive.

Marginal placental cord insertion: the need for follow up?

Objective: The objectives of this study were (1) to estimate the association between marginal placental cord insertion (PCI) and small for gestational age (SGA) and other adverse perinatal outcomes and (2) to determine if pregnancy-associated plasma protein A (PAPP-A) levels was altered in these patients.Methods: It was a retrospective cohort study of singleton pregnancies undergoing ultrasound between 2016 and 2018. Marginal PCI was defined as a distance of ≤2 cm from placental edge to PCI site, visualized in both sagittal and transverse planes, and diagnosed between 16 and 32 weeks. Velamentous PCI were excluded. The primary outcome was SGA, defined as birthweight below 10th percentile for gestational age. Pregnancies with marginal PCI were compared to those with normal PCI with respect to maternal characteristics, PAPP-A levels and adverse perinatal and delivery outcomes.Results: The incidence of marginal PCI was 4.2% (76/1819). Compared to those with a normal PCI, patients with a marginal PCI were more likely to be nulliparous and less likely to be African American or morbidly obese (p < .05). SGA rate was similar between the groups (17.6% vs. 18.1%). There was a trend toward an increased incidence of oligohydramnios, polyhydramnios and breech presentation in patients with marginal PCI; however, these did not reach statistical significance. The incidence of low PAPP-A level was comparable between the groups (18.4% vs. 14.3%, p > .05).Conclusion: Our study did not demonstrate any increase in adverse pregnancy outcomes in the presence of marginal PCI. These findings may provide reassurance for counseling patients with this sonographic finding.

The rate of undetectable genetic causes by Cell-free DNA test in congenital heart defects

Objective: The study aimed to estimate the rate of genetic causes that were undetectable by Cell-free DNA (cfDNA) test in prenatally diagnosed congenital heart defect (CHD) cases based on an assumption that cfDNA would accurately detect common aneuploidies including trisomy 21/18/13/45X, and del22q11.2.Methods: This study included prenatally diagnosed CHD cases with diagnostic genetic results. The possibility of false-positive/negative results from cfDNA testing was discarded. Thus, cfDNA results would be positive in common aneuploidies or del22q11.2 and negative in normal diagnostic genetic testing results or other genetic conditions. The rate of genetic causes that were undetectable by cfDNA test was estimated for all cases as well as for CHD subgroups.Results: Of 302 cases, 98 (34.8%) had a type of genetic abnormalities, with 67 having common aneuploidies or del22q11.2 and 31 having other genetic conditions. The rate of genetic causes that were undetectable by cfDNA test in CHD cases was 13.2% among those with assumingly negative cfDNA screen results and 10.3% among the entire study population. These rates were similar between CHD subgroups (p > .05). The rate of genetic causes that were undetectable by cfDNA test was higher in the non-isolated cases than in the isolated ones among those with assumingly negative-screen results (20.5% and 9.9%, respectively, p = .025).Conclusion: In prenatally diagnosed CDH cases, a significant number of chromosomal abnormalities are still identified after diagnostic testing even if cfDNA screen is negative, and thus it is important to extensively counsel patients with negative cfDNA screen carrying a CHD-affected fetus.

A novel approach to reduce blood loss in patients with placenta accreta spectrum disorder

OBJECTIVE

Cesarean hysterectomy for the treatment of placenta accreta spectrum (PAS) disorders has the potential to be associated with significant blood loss, massive transfusion, and operative morbidity. Two major contributors to blood loss are the hysterotomy and the bladder dissection. We introduce a new surgical technique and hypothesize that developing the hysterotomy with a linear cutter and mobilization of the bladder using a vessel sealing system (VSS) before clamping uterine arteries will lead to a total reduction in blood loss and transfusion rates.

MATERIALS AND METHODS

This was a case series, which presents clinical outcomes according to our described surgical technique. The following surgical outcomes were collected: operation time (minutes), estimated blood loss (EBL), intraoperative complications, need for reoperation before discharge, and transfusion rates. Our surgical technique utilizes a linear cutter to create a bloodless hysterotomy and a VSS to dissect the vesicouterine tissue. The VSS cauterizes and transects the small vesicouterine and placental-vesical vascular anastomoses that are prone to bleeding. Once the bladder is mobilized below the level of the cervix, the uterine arteries are ligated to complete the key components of the hysterectomy.

RESULTS

Of the 23 cases, the median EBL was 1500 cubic centimeters and patients received a median of 1 unit of packed red blood cells. Eleven of the 23 cases did not require any blood transfusion and no patients required massive transfusion. The EBL did not differ between procedures that were performed emergently versus scheduled and it also did not differ between patients that had placenta increta versus placenta percreta, as diagnosed by histopathology.

CONCLUSION

Use of a linear cutter and closure of the lower anastomosis with VSS prior to clamping uterine artery during cesarean hysterectomy can significantly reduce blood loss and transfusion rates. This technique is applicable in emergent and nonemergent settings as well as for the most challenging procedures complicated by placenta percreta.

Prolonged early antenatal indomethacin exposure is safe for fetus and neonate. J Matern Fetal Neonatal Med 2019;34:167-176. [PMID: 30905227 DOI: 10.1080/14767058.2019.1599351]

Objective: To evaluate fetal and neonatal safety of early-onset long-term antenatal indomethacin treatment (LIT) for short cervix.Methods: In this cohort study, women started LIT for short cervix (<25 mm) before completing 25 weeks. They followed a standardized regiment of oral indomethacin: 100 mg loading, 50 mg qid for 48 h, 25 mg qid until delivery or at 32 weeks gestational age (GA), whichever comes first. Weekly monitoring for oligohydramnios and ductus arteriosus (DA) constriction included confirmation of compliance with treatment/dose. This approach is established in our clinical practice. To identify LIT complications separate from prematurity, each neonate exposed to LIT were matched to two unexposed neonatal controls within ±3 days of GA of delivery and birth weight of ±10%. Odds ratios for neonatal variables included pulmonary hemorrhage, patent DA (PDA) requiring medical or surgical correction, necrotizing enterocolitis (NEC), spontaneous intestinal perforation (SIP), intraventricular hemorrhage (IVH) grade III-IV, other intracranial hemorrhage (ICH), neonatal mortality, calculated individually, and for total composite morbidity. Statistical determinants of neonatal morbidity were assessed using binary logistic regression. Exposure to LIT, maternal age, parity, BMI, GA at delivery, birth-weight (BW), neonatal gender, cord artery pH, and 5-min Apgar score were independent variables.Results: 166 LIT cases were matched with 332 controls. LIT median duration was 49 (3-108) days. Mean delivery GA was 34 weeks. LIT was stopped for 5 patients (2.9%) with oligohydramnios and 1 (0.6%) with DA constriction, without consequent morbidity. 71 cases (43%) completed LIT, stopping at 32 weeks. 95 stopped early for preterm premature ruptures of membranes (PPROM) (20%), active labor (11%) or patient choice (22%). Odds of any individual complication did not differ between treated cases and controls. LIT was not a statistical determinant of composite morbidity or any individual neonatal problem.Conclusion: Continuous early-onset indomethacin exposure, up to 15 weeks antenatally, did not increase fetal or neonatal complications. This level of safety is permissive to a randomized trial of indomethacin for the treatment of short cervix.

Harmony Behind the Trumped-Shaped Vessel: the Essential Role of the Ductus Venosus in Fetal Medicine

The ductus venosus is a fetal vessel that functions importantly in the transfer of oxygen-and nutrient-rich blood from the umbilical vein to vital organs. Its control under active regulation and its anatomy result in a flow-velocity profile that is typically forward throughout the cardiac cycle. This forward cardiac function reflects afterload, cardiac contractility, compliance, and vascular volume changes. Ductus venosus assessment gives valuable information under different fetal conditions. For example, during first trimester screening, an abnormal ductus venosus measurement changes the screening result. Assessment of ductus venosus in twin-to-twin transfusion syndrome is an essential element of staging. In fetal growth restriction, an abnormal waveform mandates imminent delivery. In this review, we will discuss the role of ductus venosus assessment and its role in antenatal management and outcome prediction in certain fetal conditions throughout pregnancy.

The role of fetal growth restriction in the association between Down syndrome and perinatal mortality

Objective: Down syndrome (DS) is associated with significant risk of perinatal mortality. We hypothesize that this association is primarily mediated through the effects of fetal growth restriction (FGR).Methods: This was a retrospective cohort analysis using the US Natality Database from 2011 to 2013. Analysis was limited to singleton nonanomalous pregnancies or confirmed DS pregnancies without severe structural anomalies between 24 and 42 w in gestation. The risk of stillbirth (SB) associated with DS was estimated using both Cox proportional Hazard (HR) regression and accelerated failure time (AFT) methods. The risk of neonatal mortality was estimated using logistic regression analyses. Mediation analysis was then performed to estimate the effect of small for gestational age (SGA), defined as birthweight ≤10th percentile for gestational age, on perinatal mortality associated with DS. All regression models were selected using backward stepwise elimination method. The final regression models included adjustment for maternal age, hypertension, and diabetes.Results: The final cohort included 2446 DS cases among 9,804,718 births. The overall SB rate was 223.6/1000 births in DS group and 4.7/1000 births without DS (p < .001, adjusted hazard ratio (aHR): 58.25; 95% CI [53.44,63.49]). Based on the AFT model, DS survival-to-delivery rate is 4.3 times lower (TR: 0.23; 95% CI [0.22,0.24]). Thirty-five percentage of the effect of DS on stillbirth was mediated through SGA (% mediation:35.1%; 95% CI [33.7,36.4]). The rate of neonatal mortality among DS was 69.0/1000 births compared with 2.8/1000 births without DS (p < .001, adjusted odds ratio (aOR): 27.16; 95% CI: [22.63,32.60]). Only 11.6% of the effect of DS on neonatal deaths was mediated through SGA (%mediation:11.6%; 95% CI [8.4,10.6]).Conclusion: Over one-third of overall stillbirths were mediated through SGA. Routine surveillance of fetal growth and standard SGA surveillance protocols may reduce the risk of perinatal mortality in DS pregnancies. Conversely, it is important to point out that these surveillance strategies may not be effective two-third of the cases not affected by growth restriction.

The factors associated with mode of delivery in fetuses with congenital heart defects

Objective: It is not evident whether the mode of delivery (MOD) should be modified in pregnancies complicated by fetal congenital heart defects (CHDs). The question as to whether MOD of CHD infants has a significant impact on neonatal outcome remains elusive. The aim of this study was to evaluate factors associated with MOD and its impact on immediate neonatal outcomes in a cohort of late preterm or term fetuses with CHDs born in a tertiary center.Methods: This retrospective study comprised of singleton pregnancies with known fetal CHDs who delivered after 34 0/7 weeks of gestation over a 7-year period. Fetuses with chromosomal abnormality or stillbirths were excluded. Obstetric risk factors were classified as maternal medical, maternal surgical or fetal comorbidities. MOD was classified as elective cesarean delivery (CD) or attempted vaginal delivery (VD). The latter was further categorized as successful VD or intrapartum CD. The study population was stratified into four categories based on the severity of cardiac abnormalities diagnosed by fetal echocardiography. Immediate neonatal outcomes included Apgar scores and umbilical cord artery pH.Results: Of a total of 222 patients, 79.8% underwent attempted VD and 20.2% had elective CD. Of the attempted VD group, 80.2% had successful VD and 19.8% had intrapartum CD. The frequencies of maternal medical, maternal surgical and fetal comorbidities were higher in the elective CD group than in the attempted VD group and also were higher in the intrapartum CD group than in the successful VD group (p < .05 for all). Multivariate logistic regression models revealed that maternal surgical or fetal comorbidities increased the chance of elective CD and maternal medical or fetal comorbidities decreased the chance of successful VD. The severity of CHDs was not an independent factor that affected MOD. Elective or intrapartum CD did not improve immediate neonatal outcomes.Conclusion: Our results demonstrated that preexisting obstetric comorbidities were significant variables that affected the MOD in fetuses with CHD. Vaginal delivery should be attempted unless obstetric and medical contraindications accompany index pregnancy.