The multidisciplinary management of placenta accreta spectrum (PAS) within a single tertiary centre: A ten-year experience

Successful multidisciplinary team management of placenta accreta spectrum disorder: A referral center model in a middle-income country

OBJECTIVE

The aim of the study was to evaluate the outcomes of placenta accreta spectrum (PAS) disorder managed by a multidisciplinary care team (MCT) compared with a conventional care team (CCT) in a PAS referral center in Thailand.

METHODS

This retrospective single-center cohort study analyzed PAS management outcomes in the PSU PAS Center between January 2010 and December 2022. The incidence of hemorrhage ≥3500 mL and the composite maternal and neonatal outcomes of PAS were compared before and after the introduction of an MCT in 2016.

RESULTS

Of 227 PAS cases, 219 (96.5%) had pathological confirmation. There were 52 (22.9%) cases of placenta accreta, 119 (52.4%) cases of placenta increta, and 56 (24.7%) cases of placenta percreta. The incidence of estimated blood loss (EBL) ≥3500 mL decreased from 61.8% to 34.3% (P < 0.001) after the establishment of the MCT. The median EBL decreased from 4000 (IQR: 2600,7250) mL to 2250 (1300, 4750) mL (P < 0.001). EBL reduction was statistically significant in the accreta and increta groups (P < 0.001). Red blood cell transfusions decreased from five (3, 9) to two (1, 6) units (P < 0.001) per patient. The length of maternal hospital stays and ICU admissions were statistically shorter when PAS was managed by an MCT (P < 0.001). The length of newborn hospital and ICU stays decreased significantly (P < 0.001).

CONCLUSION

The incidence of massive postpartum hemorrhage and a composite of maternal and neonatal morbidities in pregnant women with PAS disorder improved significantly after the establishment of an MCT to manage PAS in a middle-income country setting.

A Retrospective Study of Maternal and Neonatal Outcome in Placenta Accreta Spectrum After Planned or Emergency Delivery From a Tertiary Care Centre in North India

Aim This retrospective study aimed to evaluate the incidence, sociodemographic profile, feto-maternal outcomes, and associated risk factors of placenta accreta spectrum (PAS) among all the deliveries. Methods This retrospective cohort study included all women diagnosed with PAS either preoperatively or intraoperatively. Data on maternal high-risk factors such as previous surgical history, association with placenta praevia, parity and primary outcomes such as the operative procedure carried out, transfusion requirements and ICU admission, as well as neonatal variables such as Apgar score, NICU admission and birthweight, were among the primary outcomes of this study. The study was carried out over a period of 10 months at our centre. Results A cohort of 32 women were identified with placenta accreta, increta, or percreta. The mean maternal age was 31 years. The mean gestational age at the time of diagnosis was 32.75 weeks. Around 50% of patients had risk factors for the abnormally invasive placenta, such as placenta praevia, and 75% had a history of previous caesarean sections. Hysterectomy was done in 28 cases (87.5%). Blood transfusion was done in all the cases. There were two maternal deaths in the study group. The perinatal outcome was better in the antenatally detected cases. Conclusion An increased incidence of PAS has been seen. Early risk factor identification and strategic management improve maternal and foetal outcomes. Our findings demonstrated that PAS pregnancies managed in our centre had maternal and neonatal outcomes comparable to those in developed countries. It is hypothesized that this is because pregnancies with PAS are managed using a multidisciplinary approach.

The effect of abnormal placentation on maternal serum fetal fraction of cell-free DNA

OBJECTIVES

Abnormal placentation may affect the maternal serum fraction of cell-free fetal DNA (fetal fraction) determined as part of non-invasive prenatal screening (NIPS). This study aimed to assess whether the fetal fraction can predict placenta accreta spectrum (PAS) with or without placenta previa (PP). We also investigated the impact of trophoblastic invasion depth on the fetal fraction.

METHODS

This is a retrospective case-control study of pregnant women with and without abnormal placentation carrying a singleton and having undergone NIPS prior to 20 weeks of gestation. The eligible subjects were selected from a cohort managed at our institution for PAS suspected antenatally. We compared women with normal placentation (controls) to PAS, PP, or PAS + PP cases. Data were abstracted from electronic medical records, and PAS was confirmed histologically.

RESULTS

Of the 146 patients in our cohort, 8 controls, 10 PP, 6 PAS, and 7 PAS + PP cases were eligible for the study. Among the groups, there were no significant differences in baseline demographic and clinical characteristics except the median number of prior uterine surgeries. Also, the groups did not significantly differ in their median fetal fraction. The fetal fraction did not discriminate any group when stratified according to the depth of placental invasion, i.e., no PAS, abnormally adherent, and abnormally invasive placenta.

CONCLUSIONS

The maternal serum fraction of cell-free fetal DNA measured before 20 weeks of gestation is not predictive of PAS with or without concurrent PP or the depth of trophoblastic invasion.

Red Blood Cell Transfusion in Patients With Placenta Accreta Spectrum: A Systematic Review and Meta-analysis

OBJECTIVE

To evaluate red blood cell use during delivery in patients with placenta accreta spectrum.

DATA SOURCES

We searched MEDLINE, EMBASE, CINAHL, Cochrane Central, ClinicalTrials.gov, and Scopus for clinical trials and observational studies published between 2000 and 2021 in countries with developed economies.

METHODS OF STUDY SELECTION

Abstracts (n=4,275) and full-text studies (n=599) were identified and reviewed by two independent reviewers. Data on transfused red blood cells were included from studies reporting means and SDs, medians with interquartile ranges, or individual patient data. The primary outcome was the weighted mean number of units of red blood cells transfused per patient. Between-study heterogeneity was assessed with an I2 statistic. Secondary analyses included red blood cell usage by placenta accreta subtype.

TABULATION, INTEGRATION, AND RESULTS

Of the 599 full-text studies identified, 20 met criteria for inclusion in the systematic review, comprising 1,091 cases of placenta accreta spectrum. The number of units of red blood cells transfused was inconsistently described across studies, with five studies (25.0%) reporting means, 11 (55.0%) reporting medians, and four (20.0%) reporting individual patient data. The weighted mean number of units transfused was 5.19 (95% CI 4.12-6.26) per patient. Heterogeneity was high across studies (I2=91%). In a sensitivity analysis of five studies reporting mean data, the mean number of units transfused was 6.61 (95% CI 4.73-8.48; n=220 patients). Further quantification of units transfused by placenta accreta subtype was limited due to methodologic inconsistencies between studies and small cohort sizes.

CONCLUSION

Based on the upper limit of the CI in our main analysis and the high study heterogeneity, we recommend that a minimum of 6 units of red blood cells be available before delivery for patients with placenta accreta spectrum. These findings may inform future guidelines for predelivery blood ordering and transfusion support.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO, CRD42021240993.

Outcomes of pregnancies at high-risk for placenta accreta spectrum following negative diagnostic imaging

OBJECTIVES

To assess the pretest and negative post-test probability for placenta accreta spectrum (PAS) in a group of patients with high-risk clinical factors.

METHODS

We included patients with suspected and/or confirmed PAS at our institution over 8 years. Sonography performed by maternal-fetal medicine specialists, and selected patients underwent MRI. Imaging was considered positive if either sonography or MRI suggested PAS. Histopathology was the gold standard for diagnosis of PAS. We assessed the pretest and negative imaging-test probability, and resources required.

RESULTS

We identified 82 high-risk patients with the following: (1) a history of ≥1 cesarean section and/or intrauterine gynecologic procedure and placenta previa in the index pregnancy; (2) a history of >3 cesarean deliveries and/or gynecologic procedures regardless of placental location; (3) prior PAS disorder, or retained placenta requiring manual extraction and/or curettage, complicated by postpartum hemorrhage; and (4) suspected cesarean section scar pregnancy. Histopathology confirmed PAS in 52 patients, with pretest probability of 63%. Imaging correctly identified 44/50 cases with PAS, and excluded this condition in 24/30 cases. Thus, the positive and negative post-test probability for PAS following negative imaging was 88 and 20%, respectively. Of the six patients with false-negative imaging, all had either surgical complications or required care beyond that for routine cesarean section.

CONCLUSIONS

Although diagnostic imaging is sensitive, the negative posttest probability remains high in women with high pretest probability for PAS. Therefore, women at high risk for PAS should be managed in experienced centers by a multidisciplinary team even if imaging is negative.

Improved management of placenta accreta spectrum disorders: experience from a single institution

OBJECTIVES

To assess the applicability of a standardized multidisciplinary protocol for managing placenta accreta spectrum (PAS) disorders and its impact on the outcomes.

METHODS

We compared patients with PAS manage by a standardized multidisciplinary protocol (T2) to historic controls managed on a case-by-case basis by individual physicians between (T1). The primary outcome is composite maternal morbidity. Secondary outcomes were the rates of surgical complications, estimated blood loss, number of blood products transfused, intensive care unit admissions, ventilator use, and birth weight. Multivariate logistic analysis was used to identify independent predictors of composite maternal morbidity.

RESULTS

During T1 and T2, we managed 39 and 36 patients with confirmed PAS, respectively. During T2, the protocol could be implemented in 21 cases (58%). Compared to T1, patients managed during T2 had 70% less composite maternal morbidity (95% CI: 0.11-0.82) and lower blood loss (median, 2,000 vs. 1,100 mL, p=0.008). Also, they were 68% less likely to require transfusion of blood products (95% CI: 0.12-0.81; p=0.01), including fewer units of packed red blood cells (median, 2 vs. 0, p=0.02). Management following the protocol was the only independent factor associated with lower composite maternal morbidity (OR: 0.22; 95% CI: 0.05-0.95; p=0.04). Selected maternal and neonatal outcomes were not different among 12 and 15 patients with suspected but unconfirmed PAS disorders managed during T1 and T2, respectively.

CONCLUSIONS

Most patients can be managed under a standardized multidisciplinary protocol for PAS disorders, leading to improved outcomes.

A comparison of praevia and non-praevia outcomes in placenta accrete spectrum cases: A single centre analysis

BACKGROUND

Placenta accreta spectrum (PAS) causes severe maternal morbidity and mortality. Antenatal diagnosis can optimise maternal outcomes and reduce the risk of complications. PAS cases where the placenta is not low lying are suggested to be more difficult to diagnose antenatally and are potentially associated with different outcomes.

AIM

The aim was to compare factors associated with births in PAS pregnancies with and without placenta praevia at a single tertiary centre over 15 years.

MATERIALS AND METHODS

A retrospective review of all births complicated by PAS was conducted from a site-specific database. Cases with and without a placenta praevia were analysed to compare differences in maternal risk factors, outcomes and histological diagnosis.

RESULTS

Between June 2006 and July 2020 there were 134 cases of PAS, 106 with placenta praevia. Cases without praevia were less likely to have a history of previous caesarean section and to be admitted for delivery planning or with antepartum haemorrhage. A higher proportion of cases without praevia were delivered at term, with no overall difference in emergency or elective deliveries. There was a significantly lower rate of hysterectomy in the non-praevia group. The overall estimated blood loss was significantly lower in those without praevia.

CONCLUSION

Suspected PAS without placenta praevia is at lower risk of hysterectomy and massive blood loss. The management approach can be tailored accordingly, with good operative outcomes with transverse abdominal and uterine incisions. Antenatal diagnosis can be difficult to accurately predict the degree of invasion, and a higher level of suspicion is required.

Suspected Placenta Accreta: Using Imaging to Stratify Risk of Morbidity

OBJECTIVE

This study was aimed to compare clinical outcomes and use of interventions in women with suspected accreta based on the degree of antenatal suspicion.

STUDY DESIGN

This was a retrospective cohort study of women with suspected accreta from 2007 to 2019. Included patients had one or more imaging studies suggestive of accreta. Cases were classified as "lower risk" if imaging showed possible signs of accreta including mild or superficial myometrial infiltration, an abnormal uterine contour, an abnormal uteroplacental interface, or loss of the retroplacental hypoechoic zone and "higher risk" if there was clear evidence of more than superficial myometrial infiltration, placental tissue extruding beyond the uterine serosa, bridging vessel(s), or placental lacunae with high velocity and/or turbulent flow. The primary study outcome was a composite maternal morbidity including cesarean hysterectomy, transfusion of blood or blood products, unintentional cystotomy, or intensive care unit (ICU) admission. Chi-square, Fisher's exact test, and Mann-Whitney U-test were used for analysis.

RESULTS

A total of 78 women had a suspected accreta on imaging, 36 with "lower risk" features and 42 with "higher risk" features. There were no differences in baseline maternal demographics. Women in the "higher risk" group were more likely to have a placenta previa (p < 0.01) and preoperative consultation with gynecologic oncology (p = 0.04). There was a significant difference in composite maternal morbidity between patients with "lower risk" and "higher risk" features of accreta on imaging (50 vs. 92.9%, p < 0.01). Median gestational age at planned and actual delivery were earlier in the "higher risk" group (36.6 vs. 34.9 weeks, p < 0.01; 36.0 vs. 34.7 weeks, p < 0.01).

CONCLUSION

Stratification of women with suspected accreta based on imaging corresponded to rates of maternal morbidity and operative complications, and appears to have been used clinically in selecting timing of delivery and interventions.

KEY POINTS

· Increased morbidity with high risk accreta imaging.. · Interventions correlate with accreta imaging risk.. · Imaging can be used to stratify accreta cases..

Whole blood transfusion reduces overall component transfusion in cases of placenta accreta spectrum: a pilot program

OBJECTIVE

Placenta accreta spectrum (PAS) is a group of placental invasion pathologies associated with significant morbidity to both mother and fetus. The majority of patients with PAS will require a blood transfusion at time of delivery and subsequent cesarean hysterectomy. The optimal approach to maternal acute blood loss resuscitation is currently unknown.

METHODS

Here, we present a cohort analysis of 34 patients with pathology-confirmed PAS treated with either whole blood (n = 16) or component therapy (n = 18) for initial intraoperative resuscitation.

RESULTS

We observed comparable results in post-operative outcomes with fewer overall transfusions and subsequently, lower volumes of resuscitation (p=.03) with whole blood initial resuscitation.

CONCLUSIONS

Whole blood transfusion may represent a viable option for initial resuscitation with lower resuscitation volumes and transfusion-associated complications without directly effecting post-operative outcomes in cases of PAS.

Placenta accreta spectrum disorders-experience of management in a German tertiary perinatal centre

PURPOSE

Placenta accreta spectrum (PAS) disorders can cause major intrapartum haemorrhage. The optimal management approach is not yet defined. We analysed available cases from a tertiary perinatal centre to compare the outcome of different individual management strategies.

METHODS

A monocentric retrospective analysis was performed in patients with clinically confirmed diagnosis of PAS between 07/2012 and 12/2019. Electronic patient and ultrasound databases were examined for perinatal findings, peripartum morbidity including blood loss and management approaches such as (1) vaginal delivery and curettage, (2) caesarean section with placental removal versus left in situ and (3) planned, immediate or delayed hysterectomy.

RESULTS

46 cases were identified with an incidence of 2.49 per 1000 births. Median diagnosis of placenta accreta (56%), increta (39%) or percreta (4%) was made in 35 weeks of gestation. Prenatal detection rate was 33% for all cases and 78% for placenta increta. 33% showed an association with placenta praevia, 41% with previous caesarean section and 52% with previous curettage. Caesarean section rate was 65% and hysterectomy rate 39%. In 9% of the cases, the placenta primarily remained in situ. 54% of patients required blood transfusion. Blood loss did not differ between cases with versus without prenatal diagnosis (p = 0.327). In known cases, an attempt to remove the placenta did not show impact on blood loss (p = 0.417).

CONCLUSION

PAS should be managed in an optimal setting and with a well-coordinated team. Experience with different approaches should be proven in prospective multicentre studies to prepare recommendations for expected and unexpected need for management.

A comparison of antenatally and intraoperatively diagnosed cases of placenta accreta spectrum

Objective

To assess the effect of antenatal diagnosis of placenta accreta spectrum (PAS) on fetomaternal outcomes.

Material and Methods

This was a retrospective cohort study conducted from January 2017 to December 2018. Women with PAS diagnosed antenatally were designated as group A and those where diagnosis was suspected during operation and confirmed on histopathology (PAS diagnosed perioperatively) were designated as group B. Outcome in terms of uterine conservation, maternal death, admission of mother to intensive care unit (ICU), perinatal death and neonatal ICU (NICU) admission were recorded.

Results

During the study, PAS was confirmed in 96 cases which were included. Out of these, 34 (35.4%) cases were included in group A while 62 (64.6%) were diagnosed intraoperatively (group B). The median number of units of blood transfused was lower in group A compared to group B (4 vs 6, p<0.001). The uterus was conserved more often in group A compared with group B (67.6% vs 43.5%, p=0.024) while admission to ICU occurred significantly more often in group B (26.5% vs 59.7%, p=0.002). Maternal death (p=0.038) and perinatal death (p=0.008) were also significantly higher in group B. More neonates delivered to mothers in group B were admitted to NICU (85.7% vs 24%, p=0.033). Survival analysis showed a statistically significant increase in uterine conservation rate in group A compared with group B (log rank, p=0.04).

Conclusion

PAS diagnosed antenatally has better fetomaternal outcome than intraoperative detection of PAS. Diagnosing PAS antenatally is therefore crucial to improve management and achieve a better outcome.