Placenta accreta spectrum disorder: updates on anesthetic and surgical management strategies

The Management of Placenta Accreta Spectrum Disorder

This chapter provides insight into current management strategies for the placenta accreta spectrum (PAS). PAS is one of the most morbid conditions of pregnancy, with significant maternal hemorrhage and surgical morbidity risks, and its increasing incidence. Here, we review the available data to help guide the clinical management of PAS, from time of diagnosis through delivery and postpartum care, while acknowledging the many areas of continued uncertainty. The evidence is strong for the importance of team-based, patient-centered, and multidisciplinary care for patients with PAS. However, much else remains uncertain and is predominantly guided by expert opinion. Ultimately, we aim to provide a current understanding of available literature and to emphasize that continued research is paramount to explore management and surgical approaches to move toward optimization of patient outcomes, including the patient experience.

Multi-layered data framework for enhancing postoperative outcomes and anaesthesia management through natural language processing

Anaesthesia management is a critical aspect of perioperative care, directly influencing postoperative recovery, pain management, and patient outcomes. Despite advancements in anaesthesia techniques, variability in patient responses and unexpected postoperative complications remain significant challenges. The research proposes a multi-layered architecture named Anaesthesia CareNet for analyzing data from diverse sources to enhance personalized anaesthesia management and postoperative outcome prediction. The architecture is structured into two primary layers: Data processing and Predictive Modeling. In the Data processing layer, advanced Natural Language Processing (NLP) techniques such as Named Entity Recognition (NER), normalization, lemmatization, and stemming are applied to clean and standardize the unstructured clinical data. Generative Pre-trained Transformer 3 (GPT-3), a Large Language Model (LLM) is employed as a feature extraction method, allowing the system to process and analyze complex clinical narratives and unstructured textual data from patient records. This enables more precise and personalized predictions, not only improving anaesthesia management but also laying the groundwork for broader applications in life sciences. The extracted data is passed into the predictive modeling layer, where the Intelligent Golden Eagle Fine-Tuned Logistic Regression (IGE-LR) model is applied. By analyzing correlations between patient characteristics, surgical details, and postoperative recovery patterns, IGE-LR enables the prediction of complications, pain management requirements, and recovery trajectories beyond anaesthesia; the methodology has potential applications in diverse areas such as diagnostics, drug discovery, and personalized medicine, where large-scale data analysis, predictive modeling, and real-time adaptability are crucial for improving patient outcomes. The proposed IGE-LR method achieves higher performance with 91.7 % accuracy, 90.6 % specificity, and 90 % AUC, with a recall of 91.3 %, precision of 90.1 %, and an F1-Score of 90.4 %. By leveraging advanced NLP and predictive analytics, Anaesthesia CareNet exemplifies how AI-driven frameworks can transform life sciences, advancing personalized healthcare and creating a more precise, efficient, and dynamic approach to treatment management.

The benefit of additional embolization after perioperative balloon occlusion of pelvic artery during cesarean hysterectomy in placenta accreta spectrum

BackgroundCesarean hysterectomy in the placenta accreta spectrum (PAS) remains challenging due to difficulty in controlling perioperative bleeding.PurposeTo compare the effectiveness and safety of perioperative balloon occlusion with versus without pelvic artery embolization in PAS women who underwent a cesarean hysterectomy.Material and MethodsA total of 26 pathological confirmed cases of PAS were retrospectively reviewed and categorized into two groups: perioperative balloon occlusion at either the anterior division of the internal iliac artery or uterine artery followed by gelfoam embolization (n = 12, study group) and perioperative balloon occlusion alone (n = 14, control group). Intraoperative estimated blood loss (EBL), a unit of packed red blood cell (pRBC) transfusion, surgical time, transfer to the intensive care unit (ICU), postoperative hospitalization days, postoperative complications, and Apgar scores were compared between the two groups.ResultsThe median and interquartile range (IQR) intraoperative EBL in the study group (1200 mL [700-2100 mLl]) was significantly lower compared to those in the control group (1900 mL [1300-3200 mL]) (P = 0.044). There was no significant difference between the study and control groups in units of pRBC blood transfusion, surgical time, transfer to the ICU, postoperative length of stay, postoperative complications, and mean Apgar score at 1 min and 5 min.ConclusionThe perioperative combination of balloon occlusion followed by embolization of the pelvic artery before cesarean hysterectomy is more effective in reducing blood loss than perioperative balloon occlusion alone in PAS with no difference in postoperative complications or neonatal outcomes.

Effective utilisation of rapid infusion catheters in perioperative care: a narrative review

The Rapid Infusion Catheter (RIC) has transformed intravenous (i.v.) access, allowing for rapid fluid delivery peripherally. It may negate the need for a central vein sheath to be placed. This review explores the clinical utility of RICs while addressing technical considerations and potential risks. The RIC is a large-bore i. v. sheath available in two sizes. Its maximal flow rate is 1200 ml min-1, making it advantageous in significant blood loss scenarios such as trauma and major surgeries. Insertion involves the Seldinger technique. Monitoring and maintaining the RIC is crucial to detect and address immediate complications such as occlusions, infiltration, phlebitis, and extravasation of infusate. Although the related complications share similarities with those of other peripheral i. v. cannulae, they have a lower risk of occlusion and accidental displacement. Catheter removal should be considered once the patient is stable or alternative access is available to avoid infectious complications. Removal of the RIC needs to be performed by those educated in RIC management. Maximal flow rate is an essential factor in assessing the performance of i. v. cannulae, and studies have shown that RICs outperform other peripheral and central catheters in this regard. In conclusion, RIC offers advantages over large-bore central venous access for large-volume rapid infusions, including ease of insertion and reduced severe complications. The RIC demonstrates lower thrombosis rates and a different complication profile than peripherally inserted central catheters. Understanding the characteristics and applications of RICs can help healthcare professionals make informed decisions about their use in various medical scenarios.

A Review of Conservative Surgical Approaches for Managing Placenta Accreta Spectrum

The placenta accreta spectrum (PAS) was previously called the morbidly adherent placenta. It involves a range of pathological adherence of the placenta, including placenta increta, placenta percreta and placenta accreta, depending on the depth of invasion of anchoring villi into the myometrium and beyond. This spectrum of disorder is becoming a frequently encountered problem as a consequence of rising caesarean rates all over the world. Hysterectomy during caesarean delivery (CD) has been the conventional management of PAS. However, associated complications have prompted conservative surgery at the first sitting, with or without interventional radiology. The aim is to reduce blood loss and conserve the uterus if possible. It was decided to review the available literature on this emerging topic. Using PubMed and Google Scholar, our search focused on articles published from 2004 onwards, utilizing search terms "Placenta Accreta Spectrum" OR "Adherent Placenta" and "Caesarean Delivery". The selection for review adhered to specified inclusion/exclusion criteria and finally focused on 50 articles. It was found that published work includes the following conservative approaches: first, to leave the placenta expecting autolysis and resolution; second, to leave the placenta with the intention of a delayed hysterectomy; and third, to resort to an intraoperative arterial occlusion and follow-up. Though the primary objective of reducing blood loss at initial surgery is usually achieved, the success of uterine preservation differs. The availability of a multidisciplinary team for the surgical management of PAS is an important factor to consider. Limiting the extent of surgery at the time of CD, combined with or without arterial embolization/ballooning/ligation, reduces blood loss and limits morbidity with the potential to preserve the uterus.

Perioperative Management of Unexpected Placenta Percreta in a Twin Gestation

Placenta accreta represents a spectrum of adherent placental anomalies and is an atypical invasion of the placenta. The major predisposing factor is a prior cesarean delivery. Placenta previa is considered an additional risk factor. Twin gestation is increasingly recognized as an independent risk factor for placenta accreta spectrum (PAS) disorders. Currently, immediate hysterectomy is the gold standard treatment. The management of placenta percreta is indeed highly challenging, with significant risks for both the mother and fetus due to the aggressive nature of the condition. We present a case of intraoperative diagnosis of placenta percreta in a 37-year-old woman with twin pregnancy.

Abnormal placental development induced by repeated cesarean sections: Investigating an animal model of placenta accreta spectrum disorders

INTRODUCTION

Placenta accreta spectrum (PAS) is a serious condition associated with severe postpartum hemorrhage, leading to emergency hysterectomy. Research has predominantly focused on clinical diagnosis and the prevention of adverse maternal outcomes, but the underlying pathological mechanisms remain poorly understood, partly due to the limitations of animal models.

METHODS

In this study, we conducted up to three cesarean sections (CS) on full-term pregnant mice, since a history of multiple CS is an independent risk factor for PAS. We evaluated pregnancy outcomes, placental development, morphology, trophoblast invasion, and angiogenesis at the maternal-fetal interface to assess the impact of repeated CS.

RESULTS

Following repeated CS, the model mice displayed adverse pregnancy outcomes, including placental dysplasia, incomplete remodeling of spiral arteries, deep trophoblast invasion at the maternal-fetal interface, and reduced placental perfusion. Additionally, the mice exhibited abnormal fetal development, imbalances in angiogenic and anti-angiogenic both within the placenta and in peripheral blood.

CONCLUSION

The pathological phenotypes of placenta and adverse pregnancy outcomes observed in mice with a history of three CSs closely resemble the clinical features of PAS. This model offers a valuable tool for studying the pathogenesis of PAS and could serve as a foundation for the development of early prevention strategies.

Prenatal identification of invasive placentation using ultrasound in women with placenta previa and prior cesarean delivery

OBJECTIVE

To evaluate the performance of ultrasound for antenatal identification of invasive placentation in women with placenta previa in the setting of prior cesarean delivery.

STUDY DESIGN

This was a multicenter, retrospective, cohort study. Singleton pregnancies at risk of placenta accreta because of persistent placenta previa in the setting of prior cesarean delivery who delivered at four centers, from January 2010 to May 2020, were included in the study. For this study, pregnancies with diagnosis of accreta, increta, or percreta were considered under the umbrella term of placenta accreta. All women with placenta previa identified in the second trimester had a follow-up ultrasound at 32-34 weeks. Only those with prior cesarean delivery were considered at risk of placenta accreta. Women were considered with suspected accreta in case of suspected prenatal ultrasound. Women with suspected placenta accreta had delivery planned via cesarean hysterectomy at 34+0 - 35+6 weeks, without any attempt to remove the placenta. The primary endpoint of the study was the performance of ultrasound for antenatal identification of invasive placentation. The following ultrasound signs were evaluated: placenta lacunae; loss of clear space; increased vascularity between myometrium and placenta; intracervical lake; rail sign; uterovesical hypervascularity; increased vascularity in the inferior part of the lower uterine segment potentially extending into the parametrial region; and disruption of bladder-myometrial interface.

RESULTS

180 singleton pregnancies with placenta previa in the setting of prior cesarean delivery were identified. Of them, 155 (86.1%) had antenatal suspected placenta accreta based on ultrasound, having at least one sign of invasive placentation. Of the 155 suspected cases, 99 had confirmed placenta accreta at the time of delivery. Among the 99 cases of confirmed placenta accreta, all of them had at least one sign of invasive placentation at ultrasound. Among the 81 cases with placenta previa, prior cesarean delivery, without placenta accreta, 25/81 (30.9%) had ultrasound scan negative for sign of invasive placentation, and 56/81 (69.1%) had at least one sign of invasive placentation). In particular, 12/81 (14.8%) had placenta lacunae, 16/81 (19.8%) had loss of clear space, 20/81 (24.7%) had increased vascularity between myometrium and placenta, 9/81 (11.1%) had intracervical lake, 14/81 (17.3%) had rail sign, 14 (17.3%) had uterovesical hypervascularity, 5/81 (6.2%) had increased vascularity in the inferior part of the lower uterine segment potentially extending into the parametrial region, 8/81 (9.9%) had disruption of bladder-myometrial interface. In the group of women with confirmed placenta accreta, the most common sign recorded was the disruption of bladder-myometrial interface, being recorded in 88/99 women. Disruption of bladder-myometrial interface had the highest sensitivity in detection placenta accreta. Women with disruption of bladder-myometrial interface at ultrasound had 73-fold increase in the risk of placenta accreta compared to those who did not.

CONCLUSION

Prenatal ultrasound has an excellent diagnostic accuracy in identifying invasive placentation in women with placenta previa and prior cesarean delivery.

Complex obstetrical surgery: building a team and defining roles

As the number of placenta accreta spectrum cases continues to rise, the gap in surgical skills in labor and delivery units becomes more apparent. Recent scholarly work has highlighted the diminishing advanced surgical skills among obstetrician-gynecologists, particularly among new graduates. Therefore, it has become a practice in many institutions to refer complex cesarean deliveries and obstetrical hysterectomies to subspecialists, specifically gynecologic oncologists. Hence, in this commentary, we propose a process through which key personnel within departments of obstetrics and gynecology are identified and their appropriate level of involvement in cases of complex obstetrical surgery is delineated. In doing so, we describe the surgical skills expected from each provider level so that the cesarean delivery complexity level can be matched with specific surgical expertise. Through this process, an obstetrician-led complex obstetrical surgery team is formed. Ultimately, the goal of this process is 2-fold; first, to return cases with higher levels of surgical complexity back to obstetricians and, second, to reduce the surgical back-up burden from gynecology subspecialists such as gynecologic oncologists.

Current understanding of the pathogenesis of placenta accreta spectrum disorder with focus on mitochondrial function

AIM

The refinement of assisted reproductive technology, including the development of cryopreservation techniques (vitrification) and ovarian stimulation protocols, makes frozen embryo transfer (FET) an alternative to fresh ET and has contributed to the success of assisted reproductive technology. Compared with fresh ET cycles, FET cycles were associated with better in vitro fertilization outcomes; however, the occurrence of pregnancy-induced hypertension, preeclampsia, and placenta accreta spectrum (PAS) was higher in FET cycles. PAS has been increasing steadily in incidence as a life-threatening condition along with cesarean rates worldwide. In this review, we summarize the current understanding of the pathogenesis of PAS and discuss future research directions.

METHODS

A literature search was performed in the PubMed and Google Scholar databases.

RESULTS

Risk factors associated with PAS incidence include a primary defect of the decidua basalis or scar dehiscence, aberrant vascular remodeling, and abnormally invasive trophoblasts, or a combination thereof. Freezing, thawing, and hormone replacement manipulations have been shown to affect multiple cellular pathways, including cell proliferation, invasion, epithelial-to-mesenchymal transition (EMT), and mitochondrial function. Molecules involved in abnormal migration and EMT of extravillous trophoblast cells are beginning to be identified in PAS placentas. Many of these molecules were also found to be involved in mitochondrial biogenesis and dynamics.

CONCLUSION

The etiology of PAS may be a multifactorial genesis with intrinsic predisposition (e.g., placental abnormalities) and certain environmental factors (e.g., defective decidua) as triggers for its development. A distinctive feature of this review is its focus on the potential factors linking mitochondrial function to PAS development.

Perioperative outcomes and causes of postpartum hemorrhage in patients undergoing cesarean delivery in Thailand: A comprehensive retrospective study

BACKGROUND

This study aimed to identify the characteristics, causes, perioperative anesthetic, and obstetric outcomes of patients experiencing postpartum hemorrhage (PPH) after cesarean delivery.

METHODS

We retrospectively analyzed patients who underwent cesarean delivery at the largest university hospital in Bangkok, Thailand, during a 5-year period (January 1, 2016-December 31, 2020). PPH was defined as an estimated blood loss (EBL) of ≥ 1000 ml within 24 hours postpartum.

RESULTS

Of 17 187 cesarean deliveries during the study period, 649 patients were included for analysis. The mean EBL was 1774.3 ± 1564.4 ml (range: 1000-26 000 ml). Among the patients, 166 (25.6%) experienced massive PPH (blood loss > 2000 ml). Intraoperative blood transfusions were necessary for 264 patients (40.7%), while 504 individuals (77.7%) needed intraoperative vasopressors. The analysis revealed uterine atony as the leading cause of PPH in 62.7% (n = 407) of the patients, with abnormal placentation following at 29.3% (n = 190). Abnormal placentation was associated with a significantly higher mean EBL of 2345.0 ± 2303.9 ml compared to uterine atony, which had a mean EBL of 1504.0 ± 820.7 ml (P < 0.001). Abnormal placentation also significantly increased the likelihood of blood transfusions and hysterectomies (P < 0.001 for both) and led to more intensive care unit admissions (P = 0.032). The risk of EBL exceeding 2000 ml was markedly higher in patients with abnormal placentation (odds ratio [OR] 5.12, 95% confidence interval [CI] 3.45-7.57, P < 0.001) and in cases involving trauma to the internal organs (OR 2.33, 95% CI 1.16-4.71, P = 0.018) than in patients with uterine atony. The study documented three instances of perioperative cardiac arrest, one of which was fatal.

CONCLUSIONS

These findings highlight the importance of comprehensive perioperative management strategies, including the ready availability of adequate blood and blood products, particularly in scenarios predisposed to significant hemorrhage.

TRIAL REGISTRATION

Clinical trial registration: Clinicaltrial.gov registration number NCT04833556 (April 6, 2021).

Anesthesia and postpartum pain management for placenta accreta spectrum: The healthcare provider perspective

OBJECTIVE

To explore the management and experiences of healthcare providers around anesthetic care in placenta accreta spectrum (PAS).

METHODS

This descriptive survey study was carried out over a 6-week period between January and March 2023. Healthcare providers, both anesthesiologists and those involved in operative care for women with PAS, were invited to participate. Questions invited both quantitative and qualitative responses. Qualitative responses were analyzed using content analysis.

RESULTS

In all, 171 healthcare providers responded to the survey, the majority of whom were working in tertiary PAS referral centers (153; 89%) and 116 (70%) had more than 10 years of clinical experience. There was variation in the preferred primary mode of anesthesia for PAS cases; 69 (42%) used neuraxial only, but 58 (35%) used a combined approach of neuraxial and general anesthesia, with only 12 (8%) preferring general anesthesia. Ninety-nine (61%) were offering a routine antenatal anesthesia consultation. Content analysis of qualitative data identified three main themes, which were "variation in approach to primary mode of anesthesia", "perspectives of patient preferences", and "importance of multidisciplinary team care". These findings led to the development of a decision aid provided as part of this paper, which may assist clinicians in counseling women on their options for care to come to an informed decision.

CONCLUSIONS

Approach to anesthesia for PAS varied between healthcare providers. The final decision for anesthesia should take into consideration the clinical care needs as well as the preferences of the patient.

Anesthesia and postpartum pain management for placenta accreta spectrum: The patient perspective and recommendations for care

OBJECTIVE

Placenta accreta spectrum (PAS) is a high-risk complication of pregnancy, which often requires complex surgical intervention. There is limited literature on the patient experience during the perioperative period and postpartum pain management for PAS. Therefore, this study aims to explore the patient perspective of anesthesia care.

METHODS

Ethical approval was granted by the hospital ethics committee (EC02.2023). This was a descriptive survey study, including women with a history of pregnancy complicated by PAS who were members of two patient advocacy groups. The survey, consisting of both open and closed questions, was performed over a 6-week period between January and March 2023. Content analysis was performed on qualitative data to identify themes, and recommendations for care are suggested.

RESULTS

A total of 347 participants responded to the survey; 76% (n = 252) had a cesarean hysterectomy (n = 252), and general anesthesia was the most common primary mode of anesthesia (39%, n = 130). We identified two overarching themes: experiences of anesthesia and experience of postpartum pain management. Under experiences of anesthesia, three subthemes were identified, namely "communication with the anesthesiologist", "deferring to the expertise of the team", and "consequences of decision around the mode of anesthesia." Under postpartum pain management, two subthemes emerged: "support of specialist PAS team" and "poor pain management following PAS surgery".

CONCLUSIONS

Women want to be involved in decisions around their care, but do not always understand the consequences of their decision-making, such as missing the birth of their child. An antenatal anesthesiology consultation is important to provide women with information, explore preferences, and develop a plan of care for the birth.

Accuracy of Ultrasound in the Prediction of the FIGO Classification of Placenta Accreta Spectrum

OBJECTIVES

To evaluate the accuracy of greyscale ultrasound (US) and colour Doppler detecting placenta accreta spectrum (PAS) based on the newly recommended International Federation of Obstetrics and Gynaecology (FIGO) grading system.

METHODS

This prospective study was conducted on women diagnosed with placenta previa or low-lying placenta involving the anterior uterine wall and associated with PAS as identified by the US. Transabdominal and transvaginal greyscale US was performed on admission between 34 and 36 weeks of gestation and compared to clinical grading and histopathological examination after cesarean hysterectomy.

RESULTS

In total, 36 pregnant females who underwent a cesarean hysterectomy due to placenta previa complicated by PAS were included in this study. All patients had a history of previous cesarean deliveries, ranging from 1 to 5 deliveries. The US has an overall sensitivity of 33%, 55%, and 84.62%, and specificity of 100%, 75%, and 60% in detecting the 3 degrees of PAS, respectively. US cannot differentiate between the different subtypes of PAS grade 3 (a, b, and c).

CONCLUSION

The overall US evaluation was highly significant in predicting the FIGO diagnosis of PAS; however, all ultrasonographic signs were equally relevant in diagnosing grade 1 and/or 2 PAS and were inaccurate in differing the subtypes of PAS grade 3.

Society for Maternal-Fetal Medicine Special Statement: Emergency checklist, planning worksheet, and system preparedness bundle for placenta accreta spectrum

Placenta accreta spectrum is a life-threatening complication of pregnancy that is underdiagnosed and can result in massive hemorrhage, disseminated intravascular coagulation, massive transfusion, surgical injury, multisystem organ failure, and even death. Given the rarity and complexity, most obstetrical hospitals and providers do not have comprehensive expertise in the diagnosis and management of placenta accreta spectrum. Emergency management, antenatal interdisciplinary planning, and system preparedness are key pillars of care for this life-threatening disorder. We present an updated sample checklist for emergent and unplanned cases, an antenatal planning worksheet for known or suspected cases, and a bundle of activities to improve system and team preparedness for placenta accreta spectrum.

Placenta accreta spectrum care infrastructure: an evidence-based review of needed resources supporting placenta accreta spectrum care

The incidence of placenta accreta spectrum, the deeply adherent placenta with associated increased risk of maternal morbidity and mortality, has seen a significant rise in recent years. Therefore, there has been a rise in clinical and research focus on this complex diagnosis. There is international consensus that a multidisciplinary coordinated approach optimizes outcomes. The composition of the team will vary from center to center; however, central themes of complex surgical experts, specialists in prenatal diagnosis, critical care specialists, neonatology specialists, obstetrics anesthesiology specialists, blood bank specialists, and dedicated mental health experts are universal throughout. Regionalization of care is a growing trend for complex medical needs, but the location of care alone is just a starting point. The goal of this article is to provide an evidence-based framework for the crucial infrastructure needed to address the unique antepartum, delivery, and postpartum needs of the patient with placenta accreta spectrum. Rather than a clinical checklist, we describe the personnel, clinical unit characteristics, and breadth of contributing clinical roles that make up a team. Screening protocols, diagnostic imaging, surgical and potential need for critical care, and trauma-informed interaction are the basis for comprehensive care. The vision from the author group is that this publication provides a semblance of infrastructure standardization as a means to ensure proper preparation and readiness.

Placenta Accreta Spectrum

Placenta accreta spectrum (PAS) is one of the most dangerous conditions in pregnancy and is increasing in frequency. The risk of life-threatening bleeding is present throughout pregnancy but is particularly high at the time of delivery. Although the exact cause is unknown, the result is clear: Severe PAS distorts the uterus and surrounding anatomy and transforms the pelvis into an extremely high-flow vascular state. Screening for risk factors and assessing placental location by antenatal ultrasonography are essential for timely diagnosis. Further evaluation and confirmation of PAS are best performed in referral centers with expertise in antenatal imaging and surgical management of PAS. In the United States, cesarean hysterectomy with the placenta left in situ after delivery of the fetus is the most common treatment for PAS, but even in experienced referral centers, this treatment is often morbid, resulting in prolonged surgery, intraoperative injury to the urinary tract, blood transfusion, and admission to the intensive care unit. Postsurgical complications include high rates of posttraumatic stress disorder, pelvic pain, decreased quality of life, and depression. Team-based, patient-centered, evidence-based care from diagnosis to full recovery is needed to optimally manage this potentially deadly disorder. In a field that has relied mainly on expert opinion, more research is needed to explore alternative treatments and adjunctive surgical approaches to reduce blood loss and postoperative complications.

The anesthetic approach to a patient with placenta accreta spectrum

PURPOSE OF REVIEW

Placenta accreta poses significant risk of morbidity and mortality to a laboring patient. Here we review available treatment options, highlight trends in bleeding prevention and diagnosis that have been shown to improve patient outcome, and provide best practice suggestions. We also discuss the decision-making process for choice of anesthesia, as it is not based on a gold-standard paradigm.

RECENT FINDINGS

The use of resuscitative endovascular balloon occlusion of the aorta has been gaining popularity around the world. It has been shown to cause an equivocal reduction in perioperative bleeding in placenta accreta spectrum (PAS), reduce the rate of hysterectomies, and is a safe and relatively easy technique. There are other invasive radiology techniques that have also proven to be beneficial in bleeding prevention: balloon occlusion of hypogastric arteries intraoperatively, internal iliac artery embolization, and intraoperative ligation of the hypogastric or uterine arteries.

SUMMARY

Optimal management of PAS begins with early and definitive diagnosis. A multidisciplinary approach along with preparation of special equipment and the use of a check-list maximize the chance for success. Anesthesia could be done with all types of regional or under general, considering case-by-case factors but most importantly choosing according to the institution's best facility and skill.

Animal models of the placenta accreta spectrum: current status and further perspectives

Placenta accreta spectrum disorder (PAS) is a kind of disease of placentation defined as abnormal trophoblast invasion of part or all of the placenta into the myometrium, even penetrating the uterus. Decidual deficiency, abnormal vascular remodeling in the maternal-fetal interface, and excessive invasion by extravillous trophoblast (EVT) cells contribute to its onset. However, the mechanisms and signaling pathways underlying such phenotypes are not fully understood, partly due to the lack of suitable experimental animal models. Appropriate animal models will facilitate the comprehensive and systematic elucidation of the pathogenesis of PAS. Due to the remarkably similar functional placental villous units and hemochorial placentation to humans, the current animal models of PAS are based on mice. There are various mouse models induced by uterine surgery to simulate different phenotypes of PAS, such as excessive invasion of EVT or immune disturbance at the maternal-fetal interface, which could define the pathological mechanism of PAS from the perspective of the "soil." Additionally, genetically modified mouse models could be used to study PAS, which is helpful to exploring the pathogenesis of PAS from the perspectives of both "soil" and "seed," respectively. This review details early placental development in mice, with a focus on the approaches of PAS modeling. Additionally, the strengths, limitations and the applicability of each strategy and further perspectives are summarized to provide the theoretical foundation for researchers to select appropriate animal models for various research purposes. This will help better determine the pathogenesis of PAS and even promote possible therapy.

Interventional radiology in obstetric patients: A population-based record linkage study of use and outcomes

INTRODUCTION

Interventional radiology (IR) is a technique for controlling hemorrhage and preserving fertility for women with serious obstetric conditions such as placenta accreta spectrum (PAS) or postpartum hemorrhage. This study examined maternal, pregnancy and hospital characteristics and outcomes for women receiving IR in pregnancy and postpartum.

MATERIAL AND METHODS

A population-based record linkage study was conducted, including all women who gave birth in hospital in New South Wales or the major tertiary hospital in the neighboring Australian Capital Territory, Australia, between 2003 and 2019. Data were obtained from birth and hospital records. Characteristics and outcomes of women who underwent IR in pregnancy or postpartum are described. Outcomes following IR were compared in a high-risk cohort of women: those with PAS who had a planned cesarean with hysterectomy. Women were grouped by those who did and those who did did not have IR and were matched using propensity score and other factors.

RESULTS

We identified IR in 236 pregnancies of 1 584 708 (15.0 per 100 000), including 208 in the delivery and 26 in a postpartum admission. Two-thirds of women receiving IR in the birth admission received a transfusion of red cells or blood products, 28% underwent hysterectomy and 12.5% were readmitted within 6 weeks. Other complications included: severe maternal morbidity (29.8%), genitourinary tract trauma/repair (17.3%) and deep vein thrombosis/pulmonary embolism (4.3%). Outcomes for women with PAS who underwent planned cesarean with hysterectomy were similar for those who did and did not receive IR, with a small reduction in transfusion requirement for those who received IR.

CONCLUSIONS

Interventional radiology is infrequently used in pregnant women. In our study it was performed at a limited number of hospitals, largely tertiary centers, with the level of adverse outcomes reflecting use in a high-risk population. For women with PAS undergoing planned cesarean with hysterectomy, most outcomes were similar for those receiving IR and those not receiving IR, but IR may reduce bleeding.

Timing of delivery for placenta accreta spectrum: the Pan-American Society for the Placenta Accreta Spectrum experience

BACKGROUND

The Society for Maternal-Fetal Medicine recommends cesarean delivery with potential hysterectomy scheduled in the late preterm period between 34 0/7 and 35 6/7 weeks of gestation for prenatally suspected placenta accreta spectrum.

OBJECTIVES

We aimed to investigate clinical compliance with the recommended delivery timing window for placenta accreta spectrum and its impact on maternal and neonatal outcomes.

STUDY DESIGN

We performed a retrospective multicenter review of data from referral centers within the Pan-American Society for Placenta Accreta Spectrum. Patients with placenta accreta spectrum with both antenatal diagnosis and confirmed histopathologic findings were included. We investigated adherence to the Society for Maternal-Fetal Medicine-recommended gestational age window for delivery, and compliance was further stratified by scheduled and unscheduled delivery. We compared the outcomes for patients with scheduled delivery within vs immediately 2 weeks outside the recommended window.

RESULTS

Among 744 patients with a prenatal diagnosis of placenta accreta spectrum and placental histopathologic confirmation, 488 (66%) had scheduled delivery. Among all prenatally diagnosed placenta accreta spectrum patients, 252 (39%) delivered within the recommended window of 34 0/7 and 35 6/7 weeks gestation. For the subgroup of patients who underwent scheduled delivery (n=426), 209 (49%) had delivery in this window, 120 (28%) delivered before 34 weeks, and 97 (23%) delivered at or later than 36 weeks. In the patients with scheduled delivery, 27% of placenta accreta spectrum patients with accreta delivered in the 2 weeks immediately after the recommended window (36 0/7-37 6/7 weeks), and 22% of placenta accreta spectrum pregnancies with increta/percreta delivered in the 2 weeks immediately before the recommended delivery (32 0/7-33 6/7 weeks). The maternal outcomes among those who delivered within the recommended range vs those delivering 2 weeks before and after the recommended range were similar, regardless of placenta accreta spectrum severity.

CONCLUSION

Less than half of placenta accreta spectrum patients had scheduled delivery within the recommended gestational age of 34 0/7 to 35 6/7 weeks. The reasons for deviation from recommendations and the risks and benefits of individualized timing of delivery on the basis of risk factors and predicted outcomes warrant further investigation.

Emergencies in obstetric anaesthesia: a narrative review

We conducted a narrative review in six areas of obstetric emergencies: category-1 caesarean section; difficult and failed airway; massive obstetric haemorrhage; hypertensive crisis; emergencies related to neuraxial anaesthesia; and maternal cardiac arrest. These areas represent significant research published within the last five years, with emphasis on large multicentre randomised trials, national or international practice guidelines and recommendations from major professional societies. Key topics discussed: prevention and management of failed neuraxial technique; role of high-flow nasal oxygenation and choice of neuromuscular drug in obstetric patients; prevention of accidental awareness during general anaesthesia; management of the difficult and failed obstetric airway; current perspectives on the use of tranexamic acid, fibrinogen concentrate and cell salvage; guidance on neuraxial placement in a thrombocytopenic obstetric patient; management of neuraxial drug errors, local anaesthetic systemic toxicity and unusually prolonged neuraxial block regression; and extracorporeal membrane oxygenation use in maternal cardiac arrest.

Placenta Accreta Spectrum Disorders and Radiomics: Systematic review and quality appraisal

PURPOSE

Ultrasound and magnetic resonance imaging are the imaging modalities of choice for placenta accrete spectrum (PAS) disorders assessment. Radiomics could further increase the value of medical images and allow to overcome the limitations linked to their visual assessment. Aim of this systematic review was to identify and appraise the methodological quality of radiomics studies focused PAS disorders applications.

METHOD

Three online databases (PubMed, Scopus and Web of Science) were searched to identify original research articles on human subjects published in English. For the qualitative synthesis of results, data regarding study design (e.g., retrospective or prospective), purpose, patient population (e.g., sample size), imaging modalities and radiomics pipelines (e.g., segmentation and feature extraction strategy) were collected. The appraisal of methodological quality was performed using the Radiomics Quality Score (RQS).

RESULTS

10 articles were finally included and analyzed. All were retrospective and MRI-powered. The majority included more than 100 patients (6/10). Four were prognostic (focused on either the prediction of bleeding volume or the prediction of needed management) while six diagnostic (PAS vs not PAS classification) studies. The median RQS was 8, with maximum and minimum respectively equal to 17/36 and - 6/36. Major methodological concerns were the lack of feature stability to multiple segmentation testing and poor data openness.

CONCLUSIONS

Radiomics studies focused on PAS disorders showed a heterogeneous methodological quality, overall lower than desirable. Furthermore, many relevant research questions remain unexplored. More robust investigations are needed to foster advancements in the field and possibly clinical translation.

Anesthetic management of placenta accreta spectrum at an academic center and a comparison of the combined spinal epidural with the double catheter technique: A retrospective study

STUDY OBJECTIVES

To describe the anesthetic management and outcomes of placenta accreta spectrum (PAS) cases at our institution over a 19 year period and to compare outcomes associated with the lumbar combined spinal epidural (CSE) technique versus the double catheter technique (lumbar CSE with thoracic epidural catheter).

DESIGN

Retrospective cohort study.

SETTING

Labor and delivery unit at a tertiary care center.

PATIENTS

113 female patients who had histologically confirmed PAS on the final pathology report after cesarean delivery or cesarean hysterectomy.

INTERVENTION

Neuraxial anesthesia, including CSE and the double catheter technique, and general anesthesia for PAS cases (including scheduled and unscheduled cases and those known or unknown as PAS preoperatively).

MEASUREMENTS

The medical records were reviewed for demographic information, intraoperative management, anesthetic technique, and outcomes. We describe anesthetic management and outcomes of cases classified as scheduled vs. unscheduled and known vs. unknown PAS. We also compare the CSE and double catheter techniques with the primary outcome being conversion to general anesthesia (GA).

MAIN RESULTS

We included 113 cases: 60 (53.1%) scheduled/known cases, 12 (10.6%), scheduled/unknown cases, 22 (19.5%) unscheduled/known, and 19 (16.8%) unscheduled/unknown cases. All scheduled cases except two were started with a neuraxial technique. General anesthesia (GA) was used to start 18/41 (44%) of unscheduled cases. The double catheter technique (n = 35) was associated with a lower GA conversion rate (5.7% vs. 29.7%, P = 0.036) compared to the CSE technique (n = 37).

CONCLUSIONS

Neuraxial anesthesia is the most commonly used technique for PAS cases in our practice. The double catheter technique was associated with lower GA conversion rates compared to the CSE technique in our cohort.

Neuraxial to general anesthesia conversion has equitable intraoperative and improved post-operative outcomes compared to general anesthesia in cesarean hysterectomy for placenta accreta spectrum (PAS)

OBJECTIVE

Placenta Accreta Spectrum (PAS) represents a series of placental disorders with an estimated incidence of 1:1000. Delivery and subsequent cesarean hysterectomy for PAS is associated with significant maternal morbidity and mortality. Neuraxial anesthesia may be utilized initially with subsequent conversion to general anesthesia after delivery of the fetus as an alternative to initiating with general anesthesia.

METHODS

We performed a case-control study and analyzed 85 cases of pathology-confirmed PAS patients who underwent a cesarean hysterectomy in singleton, non-anomalous, viable pregnancies. All patients were delivered at our institution's established Placenta Accreta Program from 2005 to 2020.

RESULTS

Fifty-two (61%) patients underwent general anesthesia and 33 (39%) patients underwent neuraxial anesthesia (collectively spinal, epidural, and combined spinal-epidural) converted to general anesthesia after cesarean delivery. Baseline demographics between groups were similar. Pre-operative ASA airway assessment of III/IV was equivalent between groups (94 and 82%, p = .08). Intraoperatively, neuraxial conversion and general anesthesia were equal with respect to operative time (241 vs. 261 min, p = .47), estimated blood loss (6039 vs. 8134 mL, p = .51), and composite maternal morbidity (84.6 vs. 75.8%, p = .40). Post-operatively, ICU admission (47 vs. 46%, p = 1.0) and intensive care length of stay was equivalent (p = .07), yet the total post-operative length of stay was significantly reduced in patients who underwent neuraxial anesthesia (3.76 vs. 6.35 days, p = .02). In addition, while general anesthesia was associated with a greater sonographic suspicion for placenta percreta (40 vs. 12%, p = .007), final pathology was equivalent (52 vs. 60%, p = .5).

CONCLUSIONS

Taken together, our data show neuraxial conversion to general anesthesia has equivalent intra-operative parameters with improved post-operative outcomes when compared to general anesthesia alone in the case of cesarean hysterectomy for Placenta Accreta Spectrum disorders.

Complex Pathology and Management in the Obstetric Patient: A Narrative Review for the Anesthesiologist

Pregnant patients may present with multiple complex comorbidities that can affect peripartum management and anesthetic care. The preanesthesia clinic is the ideal setting for early evaluation of high-risk pregnant patients. Comorbidities may include cardiovascular pathology such as valvular abnormalities, septal defects, aortopathies, arrythmias and cardiomyopathies. Additional comorbidities include pulmonary conditions such as obstructive sleep apnea as well as preexisting neuromuscular and skeletal disorders that may impact anesthetic management. Hematologic conditions involving both bleeding diathesis and thrombophilias may present unique challenges for the anesthesiologist. Patients may also present with endocrinopathies including diabetes and obesity. While not as common, high-risk patients may also have preexisting gastrointestinal conditions such as liver dysfunction, renal failure, and even post-transplant status. Ongoing and prior substance abuse, obstetric conditions such as placenta accreta spectrum disorders, and fetal conditions needing ex utero Intrapartum treatment also require advanced planning. Preanesthesia evaluations also help address important ethical and cultural considerations. Counseling patients regarding anesthetic considerations as well as addressing concerns will play a role in reducing racial and ethnic disparities. Anticipatory guidance by means of pre-anesthetic planning can facilitate multidisciplinary communication and planning. This can allow for an impactful and meaningful role in the care provided, allowing for safe maternal care and optimal outcomes.