Placenta Accreta Spectrum

Uterine artery ligation before placental delivery during caesarean in patients with placenta previa accreta

To investigate the influence of uterine artery ligation before placental delivery during cesarean section on postpartum hemorrhage (PPH) and related complications in patients with placenta previa accreta.A retrospective study was conducted of data from 78 patients with pernicious placenta previa, treated at Fujian Provincial Maternal and Child Health Hospital (Fuzhou, China) between January 2014 and June 2018. Twenty-nine patients underwent uterine arterial ligation before placental delivery (UALBPD), and the other 49 patients in the control group did not undergo peri-paracentesis before the delivery of the placenta. The statistical analysis and data management were performed with SPSS 19.0.The intraoperative and postoperative complications after uterine artery ligation were compared between the 2 groups: in the UALBPD group, no woman (0.0%) underwent a subtotal cesarean hysterectomy, whereas four (8.2%) did so in the control group (P = .24). The mean number of packed red blood cell (RBC) units transfused was 3.7 ± 1.2 in the UALBPD group and 5.7 ± 3.4 units in the control group (P = .0002). The estimated blood loss was 734.2 ± 317.5 mL in the UALBPD group and 1101.6 ± 442.7 mL in the control group (P < .0001). Nine (31.0%) women in the UALBPD group underwent transfusion compared with 38 (77.6%) in the control group (P = .003). The reduction in hemoglobin was 2.63 ± 1.85 g/L in the UALBPD group and 5.41 ± 2.38 g/L in the control group (P < .0001). The reduction in hematocrit was 2.96 ± 4.07 in the UALBPD group and 6.77 ± 8.74 (%) in the control group (P = .009).Bilateral uterine artery ligation before the delivery of the placenta in women with placenta accreta can effectively reduce the amount of intraoperative blood loss, the incidence of PPH, and the risk of complications, such as hysterectomy.

Prevalence and main outcomes of placenta accreta spectrum: a systematic review and meta-analysis

OBJECTIVE DATA

The objective of this study was to evaluate the prevalence of placenta accreta spectrum in general population studies and the main maternal outcomes at delivery.

STUDY

We searched PubMed, Google Scholar, clinicalTrials.gov, and MEDLINE between 1982 and 2018. Articles that provided data on the number of cases of placenta accreta spectrum per pregnancies, births, or deliveries in a defined population were used.

STUDY APPRAISAL AND SYNTHESIS METHODS

Study characteristics were evaluated by 2 independent reviewers who used a predesigned protocol. Primary outcomes were the prevalence of placenta accreta spectrum and clinical diagnostic data at birth; the pathologic criteria were used to confirm the diagnosis. Secondary outcomes included cases that required transfusion, incidence of peripartum hysterectomy, and maternal mortality rates. Heterogeneity between studies was analyzed with the Cochran's Q-test and the I² statistics.

RESULTS

Of the 98 full-text studies that were identified, 29 articles met the defined criteria and included 22 retrospective and 7 prospective studies comprising 7001 cases of placenta accreta spectrum of 5,719,992 births. Prevalence rates ranged from 0.01-1.1% with an overall pooled prevalence of 0.17% (95% confidence interval, 0.14-0.19). Only 10 studies provided detailed histopathologic data. The pool prevalence for the adherent vs the invasive grades was 0.5 (95% confidence interval, 0.3-0.36) and 0.3 (95% confidence interval, 0.2-0.4) per 1000 births, respectively. The pooled incidence for peripartum hysterectomy was 52.2% (95% confidence interval, 38.3-66.4; I²=99.8%) and 46.9% (95 % confidence interval, 34-59.9; I²=98.8%) for hemorrhage that required transfusion. The pooled estimate of maternal death was 0.05% (95% confidence interval, 0.06-0.69; I²=73%). We found large amounts of heterogeneity between studies for all parameters and further quantification was limited because of methodologic inconsistencies between studies with regards to clinical criteria that were used for the diagnosis of the condition at birth and the histopathologic confirmation of the diagnosis and differential diagnosis between adherent and invasive accreta placentation.

CONCLUSION

This meta-analysis indicated wide variation between studies for the prevalence rate of placenta accreta spectrum and for the different grades of accreta placentation that highlighted the need for consistency in definitions that are used to describe placenta accreta spectrum at birth and in the reporting of this increasing common obstetric complication.

Development of a training program for the ultrasound screening of placenta accreta spectrum disorders

OBJECTIVE

To evaluate the impact of a training program using a systematic protocol on ultrasound signs of placenta accreta spectrum (PAS).

METHODS

Intra- and inter-observer variability rates and sensitivity were tested, before and after additional training, by two research fellows with a prior basic training in obstetric ultrasound using digitally recorded second-trimester ultrasound images from cases of anterior placenta previa with and without PAS.

RESULTS

Fifty-two cases of anterior placenta previa with PAS (n=26) and without PAS (n=26) were included in the study. The highest level of inter-observer agreement for ultrasound signs was found for the absence of placental bulge and/or focal exophytic mass on gray-scale imaging and the absence of subplacental hypervascularity, bridging vessels and lacunar feeder vessels on color Doppler imaging. The level of inter-observer agreement increased from 39% before training to 40% after training; the numbers agreed as PAS by both trainees increased from four to 20. No cases were classified as inconclusive after training. There was a significant (P<0.001) change in sensitivity for both trainees after training.

CONCLUSION

Additional training in detecting the ultrasound signs associated with PAS using a standardized protocol improves the diagnostic accuracy of operators with only a basic obstetric ultrasound training.

Surgical Management of Placenta Accreta Spectrum

This is a discussion of the standard surgical treatment of placenta accreta spectrum disorders including preoperative considerations, diagnostic imaging, surgical steps for cesarean hysterectomy, and postoperative management.

Conservative Management of Placenta Accreta Spectrum

The purpose of this review was to assist obstetricians and gynecologists in considering the most appropriate conservative treatment option to manage women with placenta accreta spectrum according to their individual need and local expertise of the heath care team. The issue is challenging, as the quality of evidence with regard to efficacy is poor, and is mainly based on retrospective studies with limited sample size.

Severe Maternal Morbidity in Canada: Temporal Trends and Regional Variations, 2003-2016

OBJECTIVE

This study sought to quantify temporal trends and provincial and territorial variations in severe maternal morbidity (SMM) in Canada.

METHODS

The study used data on all hospital deliveries in Canada (excluding Québec) from 2003 to 2016 to examine temporal trends and from 2012 to 2016 to study regional variations. SMM was identified using diagnosis and intervention codes. Contrasts among periods and regions were quantified using rate ratios (RRs) and 95% confidence intervals (CIs). Temporal changes were also assessed using chi-square tests for trend (Canadian Task Force Classification II-1).

RESULTS

The study population included 3 882 790 deliveries between 2003 and 2016 and 1 418 545 deliveries between 2012 and 2016. Severe hemorrhage rates increased from 44.8 in 2003 to 62.4 per 10 000 deliveries in 2012 (P for trend <0.0001) and then declined to 41.8 per 10 000 deliveries in 2016 (P for trend <0.0001). Maternal intensive care unit admission and sepsis rates decreased between 2003 and 2016, whereas rates of stroke, severe uterine rupture, hysterectomy, obstetric embolism, shock, and assisted ventilation increased. Rates of composite SMM in 2012-2016 were higher in Newfoundland and Labrador (RR 1.15; 95% CI 1.04-1.26), Nova Scotia (RR 1.11; 95% CI 1.03-1.19), New Brunswick (RR1.22; 95% CI 1.13-1.32), Manitoba (RR 1.09; 95% CI 1.03-1.15), Saskatchewan (RR 1.15; 95% CI 1.09-1.22), the Yukon (RR 1.74; 95% CI 1.35-2.25), and Nunavut (RR 1.76; 95% CI 1.46-2.11) compared with the rest of Canada, whereas rates were lower in Alberta and British Columbia.

CONCLUSION

This surveillance report helps inform clinical practice and public health policy for improving maternal health in Canada.

Prenatal planning of placenta previa: diagnostic accuracy of a novel MRI-based prediction model for placenta accreta spectrum (PAS) and clinical outcome

PURPOSE

To investigate the diagnostic accuracy of MRI for placenta accreta spectrum (PAS) and clinical outcome prediction in women with placenta previa, using a novel MRI-based predictive model.

METHODS

Thirty-eight placental MRI exams performed on a 1.5T scanner were retrospectively reviewed by two radiologists in consensus. The presence of T2 dark bands, myometrial thinning, abnormal vascularity, uterine bulging, placental heterogeneity, placental protrusion sign, placental recess, and percretism signs was scored using a 5-point scale. Pathology and clinical intrapartum findings were the standard of reference for PAS, while intrapartum/peripartum bleeding and emergency hysterectomy defined the clinical outcome. Receiver-operating characteristic (ROC) analysis and discriminant function analysis were performed to test the predictive power of MRI findings for both PAS and clinical outcome prediction.

RESULTS

Abnormal vascularity and percretism signs were the two most predictive MRI features of PAS. The area under the curve (AUC) of the predictive function was 0.833 (cutoff 0.39, 67% sensitivity, 100% specificity, p = 0.001). Percretism signs and myometrial thinning were the two most predictive MRI features of poor outcome. AUC of the predictive function was 0.971 (cutoff - 0.55, 100% sensitivity, 77% specificity, p < 0.001).

CONCLUSION

The diagnostic accuracy of MRI, especially considering the combination of the most predictive MRI findings, is higher when the target of the prediction is the clinical outcome rather than the PAS.

Uterine Artery Embolization following Cesarean Delivery but prior to Hysterectomy in the Management of Patients with Invasive Placenta

PURPOSE

To evaluate outcomes of patients with placenta accreta spectrum (PAS) disorders who underwent uterine artery embolization (UAE) following cesarean delivery but before hysterectomy.

MATERIALS AND METHODS

A retrospective review of patients with PAS treated with cesarean-hysterectomy (C-hyst) was performed. Patients in the UAE group underwent UAE after cesarean delivery but before hysterectomy; patients in the control group underwent C-hyst alone. Estimated blood loss (EBL), transfusion requirements, length of intensive care unit (ICU) stay, and adverse events were evaluated.

RESULTS

The study included 31 patients, 7 in the UAE group and 24 in the control group. Median EBL, transfusion requirements, and length of ICU stay in the UAE group compared with control group were 1,500 mL (range, 500-2,000 mL) vs 2,000 mL (range, 1,000-4,500 mL) (P = .04), 150 mL (range, 0-650 mL) vs 550 mL (range, 0-3,125 mL) (P = .10), and 0 d (range, 0-1 d) vs 0.5 d (range, 0-2 d) (P = .07). All patients in the UAE group had placenta increta; patients in the control group had placenta accreta (29%), increta (54%), and percreta (17%) (P = .10). Subgroup analysis of patients with placenta increta demonstrated that the UAE group had a significant decrease in median EBL (P = .004), transfusion requirements (P = .009), and length of ICU stay (P = .04). No adverse events following UAE were noted.

CONCLUSIONS

UAE following cesarean delivery but before hysterectomy in patients with placenta increta appears to be safe and effective in decreasing EBL, transfusion requirements, and length of ICU stay compared with C-hyst alone.

Surgical Management of the Placenta Accreta Spectrum: An Institutional Experience

OBJECTIVE

The incidence of placenta accreta spectrum (PAS) has risen over the past decades, primarily in response to increasing Caesarean section rates. The surgical management of PAS is associated with significant morbidity, including hemorrhage and intensive care unit (ICU) admission. This study sought to evaluate the surgical outcomes of a PAS operative approach.

METHODS

A single-centre retrospective chart review of all Caesarean hysterectomies for PAS by an assigned surgeon over a 16-year period was performed. Surgical outcomes were described (Canadian Task Force Classification II-2).

RESULTS

The described surgical approach involves a midline skin incision, high midline hysterotomy, a rapid single-layer uterine closure with no placental removal attempt, constant cephalad uterine traction, and liberal choice of subtotal hysterectomy. A total of 47 patients were included: 19 (40.4%) with placenta accreta, 14 (29.8%) with placenta increta, and 14 (29.8%) with placenta percreta. Mean estimated blood loss was 1416 ± 699 mL, and mean operative time was 112 ± 49 minutes. Overall, 16 patients (34.0%) required blood transfusion, and 4 patients (8.5%) required ICU admission. The average hospitalization was 5.2 days, with no re-admission within 30 days. The use of internal iliac balloons did not result in a difference in blood loss or operative time (P > 0.05). Patients with placenta percreta had significantly more blood loss (P = 0.02) and longer operative time (P = 0.007) compared with those with placenta accreta and increta.

CONCLUSION

The current surgical model for planned Caesarean hysterectomy for PAS exhibits a low complication rate. Further research is needed for developing a standardized approach to the management of PAS.

Creating a Multidisciplinary Placenta Accreta Program

OBJECTIVE

To develop a formalized comprehensive placenta accreta (PA) program to improve maternal and neonatal outcomes associated with a PA birth.

DESIGN

To develop a clinically innovative PA program, goals were identified and teams were created to collaboratively address best practices in each phase of clinical patient care, along with the financial and marketing aspects necessary for a sustainable program.

SETTING/LOCAL PROBLEM

A Level 3 perinatal center in the Southwestern United States.

IMPLEMENTATION

A diverse multidisciplinary team addressed each aspect of care associated with a PA birth, including team members from the main operating room; trauma surgery; blood bank; interventional radiology unit; NICU; and gynecology-oncology, anesthesia, and urology departments.

MEASUREMENTS

Pre- and postprogram clinical outcome measures were examined including estimated blood loss at birth, postbirth ICU transfers and length of stay, and postpartum length of stay.

RESULTS

Clinical outcomes after program implementation showed decreased blood loss at birth (from an estimated 6,350 ml to 1,300-1,400 ml), reduced postbirth ICU length of stay (from approximately 3 days to less than 1 day, with many women bypassing ICU transfer altogether), and shortened postpartum length of stay (from 8 days to 4 days).

CONCLUSION

With implementation of this PA program, women receive a proactive approach to care that includes education, holistic care, and an organized team approach to birth made possible by the innovative care delivery model, structures, and processes. Standardized checklists and workflows help each clinician understand his or her role in the process, and resources are directed effectively and efficiently. Multidisciplinary, multispecialty collaboration results in decreased variation in care with associated improved patient outcomes.