Perioperative prophylactic internal iliac artery balloon occlusion in the prevention of postpartum hemorrhage in placenta previa: a randomized controlled trial

Exploring the Limits of Artificial Intelligence for Referencing Scientific Articles

OBJECTIVE

 To evaluate the reliability of three artificial intelligence (AI) chatbots (ChatGPT, Google Bard, and Chatsonic) in generating accurate references from existing obstetric literature.

STUDY DESIGN

 Between mid-March and late April 2023, ChatGPT, Google Bard, and Chatsonic were prompted to provide references for specific obstetrical randomized controlled trials (RCTs) published in 2020. RCTs were considered for inclusion if they were mentioned in a previous article that primarily evaluated RCTs published by the top medical and obstetrics and gynecology journals with the highest impact factors in 2020 as well as RCTs published in a new journal focused on publishing obstetric RCTs. The selection of the three AI models was based on their popularity, performance in natural language processing, and public availability. Data collection involved prompting the AI chatbots to provide references according to a standardized protocol. The primary evaluation metric was the accuracy of each AI model in correctly citing references, including authors, publication title, journal name, and digital object identifier (DOI). Statistical analysis was performed using a permutation test to compare the performance of the AI models.

RESULTS

 Among the 44 RCTs analyzed, Google Bard demonstrated the highest accuracy, correctly citing 13.6% of the requested RCTs, whereas ChatGPT and Chatsonic exhibited lower accuracy rates of 2.4 and 0%, respectively. Google Bard often substantially outperformed Chatsonic and ChatGPT in correctly citing the studied reference components. The majority of references from all AI models studied were noted to provide DOIs for unrelated studies or DOIs that do not exist.

CONCLUSION

 To ensure the reliability of scientific information being disseminated, authors must exercise caution when utilizing AI for scientific writing and literature search. However, despite their limitations, collaborative partnerships between AI systems and researchers have the potential to drive synergistic advancements, leading to improved patient care and outcomes.

KEY POINTS

· AI chatbots often cite scientific articles incorrectly.. · AI chatbots can create false references.. · Responsible AI use in research is vital..

Efficacy and safety of prophylactic balloon occlusion in the management of placenta accreta spectrum disorder: a retrospective cohort study

OBJECTIVE

Placenta accreta spectrum disorder (PAS) is a serious obstetric complication associated with significant maternal morbidity and mortality. Prophylactic balloon occlusion (PBO), as an intravascular interventional therapies, has emerged as a potential management strategy for controlling massive hemorrhage in patients with PAS. However, current evidence about the clinical application of PBO in PAS patients are still controversial. This study aimed to evaluate the effectiveness and safety of PBO in the management of PAS.

METHODS

A retrospective cohort study including PAS patients underwent cesarean delivery was conducted in a tertiary hospital from January 2015 to March 2022. Included PAS patients were further divided into balloon and control groups by whether PBO was performed. Groups were compared for demographic characteristics, intraoperative and postoperative parameters, maternal and neonatal outcomes, PBO-related complication and follow up outcomes. Additionally, multivariate-logistic regression analysis was performed to determine the definitive associations between PBO and risk of massive hemorrhage and hysterectomy.

RESULTS

A total of 285 PAS patients met the inclusion criteria were included, of which 57 PAS patients underwent PBO (PBO group) and 228 women performed cesarean section (CS) without PBO (control group). Irrespective of the differences of baseline characteristics between the two groups, PBO intervention did not reduce the blood loss, hysterectomy rate and postoperative hospital stay, but it prolonged the operation time and increased the cost of hospitalization (All P < 0.05) Additionally, there were no significant differences in postoperative complications, neonatal outcomes, and follow-up outcomes(All P > 0.05). In particular, patients undergoing PBO were more likely to develop the venous thrombosis postoperatively (P = 0.001). However, multivariate logistic regression analysis showed that PBO significantly decreased the risk of massive hemorrhage (OR 0.289, 95%CI:0.109-0.766, P = 0.013). The grade of PAS and MRI with S2 invasion were the significant risk factors affecting massive hemorrhage(OR:6.232 and OR:5.380, P<0.001).

CONCLUSION

PBO has the potential to reduce massive hemorrhage in PAS patients undergoing CS. Obstetricians should, however, be aware of potential complications arising from the PBO. Additionally, MRI with S2 invasion and PAS grade will be useful to identify PAS patients who at high risk and may benefit from PBO. In brief, PBO seem to be a promising alternative for management of PAS, yet well-designed randomized controlled trials are needed to convincingly demonstrate its benefits and triage the necessity of PBO.

Placenta accreta spectrum into the parametrium, morbidity differences between upper and lower location

OBJECTIVE

To demonstrate the surgical and morbidity differences between upper and lower parametrial placenta invasion (PPI).

MATERIALS AND METHODS

Forty patients with placenta accreta spectrum (PAS) into the parametrium underwent surgery between 2015 and 2020. Based on the peritoneal reflection, the study compared two types of parametrial placental invasion (PPI), upper or lower. Surgical approach to PAS follows a conservative-resective method. Before delivery, surgical staging by pelvic fascia dissection established a final diagnosis of placental invasion. In upper PPI cases, the team attempted to repair the uterus after resecting all invaded tissues or performing a hysterectomy. In cases of lower PPI, experts performed a hysterectomy in all cases. The team only used proximal vascular (aortic occlusion) control in cases of lower PPI. Surgical dissection for lower PPI started finding the ureter in the pararectal space, ligating all the tissues (placenta and newly formed vessels) to create a tunnel to release the ureter from the placenta and placenta suppletory vessels. Overall, at least three pieces of the invaded area were sent for histological analysis.

RESULTS

Forty patients with PPI were included, 13 in the upper parametrium and 27 in the lower parametrium. MRI indicated PPI in 33/40 patients; in three, the diagnosis was presumed by ultrasound or medical background. The intrasurgical staging categorizes 13 cases of PPI performed and finds diagnosis in seven undetected cases. The expertise team completed a total hysterectomy in 2/13 upper PPI cases and all lower PPI cases (27/27). Hysterectomies in the upper PPI group were performed by extensive damage of the lateral uterine wall or with a tube compromise. Ureteral injury ensued in six cases, corresponding to cases without catheterization or incomplete ureteral identification. All aortic vascular proximal control (aortic balloon, internal aortic compression, or aortic loop) was efficient for controlling bleeding; in contrast, ligature of the internal iliac artery resulted in a useless procedure, resulting in uncontrollable bleeding and maternal death (2/27). All patients had antecedents of placental removal, abortion, curettage after a cesarean section, or repeated D&C.

CONCLUSIONS

Lower PAS parametrial involvement is uncommon but associated with elevated maternal morbidity. Upper and lower PPI has different surgical risks and technical approaches; consequently, an accurate diagnosis is needed. The clinical background of manual placental removal, abortion, and curettage after a cesarean or repeated D&C could be ideally studied to diagnose a possible PPI. For patients with high-risk antecedents or unsure ultrasound, a T2 weight MRI is always recommended. Performing comprehensive surgical staging in PAS allows the efficient diagnosis of PPI before using some procedures.

Anatomical basis for the uterine vascular control: implications in training, knowledge, and outcomes

The efficiency of uterine vascular control depends on the precise management of its arterial pedicles and anastomotic network. Although all specialists know the uterine and ovarian arteries, only a few are familiar with the anatomy of the inferior supply system and the connections of the pelvic vessels. For this reason, specific proven inefficient hemostatic procedures are still used worldwide. The pelvic arterial system is extensively interconnected with the aortic, internal iliac, external iliac, and femoral anastomotic components. Most uterine vascular control methods act on the blood supply to the uterus and ovary but rarely on the anastomotic network of the internal pudendal artery. Therefore, the effectiveness of vascular control procedures depends on the topographic area in which they are performed. In addition, the procedure's effectiveness depends on the skill and experience of the operator, among other factors. From a practical point of view, the uterine arterial supply is divided into 2 sectors, sector S1, which involves the uterine body, supplied by the uterine and ovarian arteries, and sector S2, which includes the uterine segment, the cervix, and the upper part of the vagina, provided by pelvis subperitoneal pedicles arising from the internal pudendal artery. As both sectors receive different arterial pedicles, the hemostatic procedures for one or the other are also different. The urgent nature of obstetrical hemorrhage, correct application of a specific technique, surgeon experience, time to provide accurate informed consent in a person under a life-threatening condition, lack of precise or possible harmful consequences of the proposed method, lack of randomized controlled trials or multiple phase II trials, epidemiologic data, qualitative data, and reports from the field from clinicians using an intervention multiple other aspects could be impossible to randomize all patients to obtain more precise information. Apart from actual effectiveness, there are no reliable morbidity data, as most complications are rarely published for various reasons. However, a simple and current presentation of pelvic and uterine blood supply and its anastomotic system allows readers to understand the value of different hemostatic procedures.

Efficacy of resuscitative endovascular balloon occlusion of the aorta for hemorrhage control in patients with abnormally invasive placenta: a historical cohort study

BACKGROUND

Patients with abnormally invasive placenta (AIP) are at high risk of massive postpartum hemorrhage. Resuscitative endovascular balloon occlusion of the aorta (REBOA), as an adjunct therapeutic strategy for hemostasis, offers the obstetrician an alternative for treating patients with AIP. This study aimed to evaluate the role of REBOA in hemorrhage control in patients with AIP.

METHODS

This was a historical cohort study with prospectively collected data between January 2014 to July 2021 at a single tertiary center. According to delivery management, 364 singleton pregnant AIP patients desiring uterus preservation were separated into two groups. The study group (balloon group, n = 278) underwent REBOA during cesarean section, whereas the reference group (n = 86) did not undergo REBOA. Surgical details and maternal outcomes were collected. The primary outcome was estimated blood loss and the rate of uterine preservation.

RESULTS

A total of 278 (76.4%) participants experienced REBOA during cesarean section. The patients in the balloon group had a smaller blood loss during cesarean Sect. (1370.5 [752.0] ml vs. 3536.8 [1383.2] ml; P < .001) and had their uterus salvaged more often (264 [95.0%] vs. 23 [26.7%]; P < .001). These patients were also less likely to be admitted to the intensive care unit after delivery (168 [60.4%] vs. 67 [77.9%]; P = .003) and had a shorter operating time (96.3 [37.6] min vs. 160.6 [45.5] min; P < .001). The rate of neonatal intensive care unit admission (176 [63.3%] vs. 52 [60.4%]; P = .70) and total maternal medical costs ($4925.4 [1740.7] vs. $5083.2 [1705.1]; P = .13) did not differ between the two groups.

CONCLUSIONS

As a robust hemorrhage-control technique, REBOA can reduce intraoperative hemorrhage in patients with AIP. The next step is identifying associated risk factors and defining REBOA inclusion criteria to identify the subgroups of AIP patients who may benefit more.

Risk factors of MRI findings for predicting patient outcomes of placenta accreta spectrum and placenta previa after prophylactic balloon occlusion of the internal iliac artery

PURPOSE

Our study aimed to identify the risk factors of magnetic resonance imaging (MRI) findings for predicting patient outcomes of placenta accreta spectrum (PAS) and placenta previa after prophylactic balloon occlusion of the internal iliac artery (PBOIIA).

MATERIALS AND METHODS

This retrospective analysis was performed using the clinical records of 46 patients diagnosed with PAS and placenta previa who underwent PBOIIA during caesarean section (CS). The possible clinical risk factors for adverse maternal outcomes were evaluated by consulting patients' clinical records. The inclusion criteria for the massive bleeding group were as follows: estimated blood loss (EBL) > 2500 mL, packed red blood cell (pRBC) transfusion (>4 units), and need for hysterectomy or transcatheter arterial embolization after delivery. The MRI features were compared between the massive and non-massive bleeding groups.

RESULTS

Patients in the massive bleeding group (n = 22) had a significantly longer operation time (p < 0.001), more EBL (p < 0.001), more pRBC transfusions (p < 0.001), and a prolonged postoperative hospital stay (p < 0.05). MRI features showed a T2 dark bands, placenta bulge, and abnormal blood vessels in the placental bed more frequently in the massive bleeding group (p < 0.05). In the multiple logistic regression analysis, T2 dark bands (odds ratio 9.1, p = 0.048) and placental bulge (odds ratio 5.1, p = 0.014) remained statistically significant.

CONCLUSION

T2 dark bands and placental bulges observed on an MRI can predict adverse maternal outcomes in patients with PAS and placenta previa undergoing PBOIIA. If these findings are observed on a preoperative MRI, effective management strategies should be prepared for the possibility of massive hemorrhage during CS.

Curative effect of cervical lifting suture combined with the improved Hayman suture in pernicious placenta previa under noninterventional conditions: A retrospective cohort study

OBJECTIVE

To propose a novel operative strategy involving cervical lifting suture (CLS) in conjunction with the improved Hayman suture (CLS-Hayman) to apply in the cesarean section of pernicious placenta previa (PPP) under noninterventional conditions and evaluate the curative effect of the CLS-Hayman operation by comparing with conventional CLS.

METHODS

A retrospective cohort study was conducted on 119 pregnant women diagnosed with PPP, including 50 cases in the CLS-Hayman group and 69 cases in the CLS group. The authors used different statistical methods to compare intraoperative bleeding, 24-h postpartum bleeding, postoperative complication rates, and uterine involution between the two groups under noninterventional conditions.

RESULTS

The median intraoperative blood loss was 800 mL in the CLS-Hayman group versus 1000 mL in the CLS group. The amount of 24-h postpartum bleeding in the CLS-Hayman group was lower than that in the CLS group. The complication rates in the two groups were 12% and 27.5%, respectively (P = 0.04). B-ultrasound or magnetic resonance imaging data showed that the uterine involution was better in the CLS-Hayman group.

CONCLUSION

The CLS-Hayman suture achieves the desired intraoperative hemostasis and also stands out for its better prevention of postpartum hemorrhage, better prognosis at follow-up, and lower complication rates.

Potential resolution of placenta previa from the 28th-to the 36th-week of pregnancy: A retrospective longitudinal cohort study

INTRODUCTION

Placenta previa greatly contributes to severe antenatal and post-partum hemorrhage. Previous studies have mainly focused on the risk factors of placenta previa, with very few studies reporting which factors may affect the potential resolution of 28th-week previa. This study aimed to investigate the impact of maternal characteristics on potential resolution of placenta previa from the 28th-to the 36th-week of pregnancy.

METHODS

A retrospective longitudinal sub-cohort investigation was carried out among 368 pregnant women with 28th-week previa from the Longitudinal Placenta Previa Study (LoPPS). Logistic regression analysis was used to discover the connections between maternal covariates and the placental potential resolution. Multivariable linear regression analysis was used to detect the associations between perioperative characteristics and volume of intraoperative bleeding.

RESULTS

Among pregnant women whose placenta completely or partially covered the internal os at the 28th-week of pregnancy, 37.5% were without placenta previa at the 36th-week and 25.8% converted into marginal placenta previa. There were significant correlation between placenta previa type and GHD (Beta: 2.808, 95% CI: 1.642, 7.138; p = 0.041), type of 28th-week previa (Beta: 6.767, 95% CI: 1.592, 18.767; p < 0.001), and number of prior cesarean sections (Beta: 3.326, 95% CI: 1.580, 9.081; p < 0.001).

DISCUSSION

62.5% of the pregnant women with 28th-week placenta previa were still with previa at the 36 weeks of gestation (25.8% with marginal and 36.7% with partial/complete placenta previa). This proportion is even higher for 28th-week complete placenta previa.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2100054068, December 8, 2021.

Outcomes of prophylactic abdominal aortic balloon occlusion in patients with placenta previa accreta: a propensity score matching analysis

Background

Placenta previa accreta is a life-threatening pregnancy complication, and reducing blood loss during operative treatment remains a major challenge. The aim of our study was to investigate the effect of prophylactic abdominal aortic balloon occlusion (AABO) during caesarean section in women with placenta previa accreta.

Methods

A retrospective study of women with placenta previa accreta was conducted in a tertiary hospital from January 1, 2015, to December 31, 2020. Women were divided into balloon and control groups by whether AABO was performed. Baseline characteristics and pregnancy outcomes were compared in the two groups. A propensity score analysis was applied to minimise the indication bias. The primary outcome was composite, including estimated blood loss (EBL) ≥ 2.0 L, massive transfusion and hysterectomy.

Results

A total of 156 patients participated in this study, with 68 in the balloon group and 88 in the control group. Propensity score analysis showed that women in the balloon group had less EBL (1590.36 ± 1567.57 vs. 2830.36 ± 2285.58 mL, P = 0.02) as well as a lower proportion of EBL ≥ 1.0 L (50.00% vs. 78.57%, P = 0.03), EBL ≥ 2.0 L (21.43% vs. 50.00%, P = 0.03) and EBL ≥ 3.0 L (14.29% vs. 42.86%, P = 0.04). In addition, women in the control group received more red blood cell transfusions (8.43 U ± 9.96 vs. 3.43 U ± 6.27, P = 0.03), and the proportion of massive transfusions was higher (35.71% vs. 7.14%, P = 0.02). The proportions of disseminated intravascular coagulation (0% vs. 28.57%, P < 0.01), haemorrhagic shock (3.57% vs. 32.14%, P = 0.02) and hysterectomy (10.71% vs. 39.29%, P = 0.03) were significantly lower in the balloon group. Sutures were performed more often in the balloon group (64.29% vs. 17.86%, P < 0.01). Multivariate logistic regression analysis showed that AABO was associated with the primary outcome (adjusted odds ratio 0.46, 95% confidence interval 0.23 ~ 0.96, P = 0.04). No serious balloon catheter-related complications occurred in the balloon group.

Conclusion

AABO was an effective and safe approach to improve maternal outcomes for patients with placenta previa accreta.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04837-2.

Prophylactic endovascular internal iliac balloon placement during cesarean hysterectomy for placenta accreta spectrum

BACKGROUND

The utility of prophylactic endovascular internal iliac balloon placement in the surgical management of placenta accreta spectrum is debated.

OBJECTIVE

In this study, we review outcomes of surgical management of placenta accreta spectrum with and without prophylactic endovascular internal iliac balloon catheter use at a single institution.

STUDY DESIGN

This is a retrospective cohort study of consecutive viable singleton pregnancies with a confirmed pathologic diagnosis of placenta accreta spectrum undergoing scheduled delivery from October 2018 through November 2020. In the T1 period (October 2018-August 2019), prophylactic endovascular internal iliac balloon catheters were placed in the operating room before the start of surgery. Balloons were inflated after neonatal delivery and deflated after hysterectomy completion. In the T2 period (September 2019-November 2020), endovascular catheters were not used. In both time periods, all surgeries were performed by a dedicated multidisciplinary team using a standardized surgical approach. The outcomes compared included the estimated blood loss, anesthesia duration, operating room time, surgical duration, and a composite of surgical complications. Comparisons were made using the Wilcoxon rank-sum test and the Fisher exact test.

RESULTS

A total of 30 patients were included in the study (T1=10; T2=20). The proportion of patients with placenta increta or percreta was 80% in both groups, as defined by surgical pathology. The median estimated blood loss was 875 mL in T1 and 1000 mL in T2 (P=.84). The proportion of patients requiring any packed red blood cell transfusion was 60% in T1 and 40% in T2 (P=.44). The proportion of patients requiring >4 units of packed red blood cells was 20% in T1 and 5% in T2 (P=.25). Surgical complications were observed in 1 patient in each group. Median operative anesthesia duration was 497 minutes in T1 and 296 minutes in T2 (P<.001). Median duration of operating room time was 498 minutes in T1 and 205 minutes in T2 (P<.001). Median surgical duration was 227 minutes in T1 and 182 minutes in T2 (P<.05). The median duration of time for prophylactic balloon catheter placement was 74 minutes (range, 46-109 minutes). The median postoperative length of stay was similar in both groups (6 days in T1 and 5.5 days in T2; P=.36).

CONCLUSION

The use of prophylactic endovascular internal iliac balloon catheters was not associated with decreased blood loss, packed red blood cell transfusion, or surgical complications. Catheter use was associated with increased duration of anesthesia, operating room time, and surgical time.

Application of Abdominal Aortic Balloon Occlusion Combined with Tourniquet in Pregnant Women with Severe Placenta Accreta Spectrum

OBJECTIVE

Abdominal aortic balloon occlusion (AABO) is a vascular intervention method that has been widely used in the treatment of severe placenta accreta spectrum (PAS). The aim of this study was to investigate the benefits, potential risks, and characteristics of AABO combined with tourniquet binding of the lower uterine segment (LUS) in treatment of pregnant women with PAS.

METHODS

In this study, 64 pregnant women with PAS scores greater than 5 were enrolled as research subjects and divided into two groups. Group A (n=34) underwent normal operative procedures including tourniquet binding of the LUS. Group B (n=30) underwent AABO combined with tourniquet binding of the LUS. General clinical characteristics, ultrasonography PAS score, intraoperative blood loss (IBL), blood loss within 24 h after surgery (24-h BL), postoperative complications, and neonatal data of the two groups were retrospectively reviewed. The influencing factors of IBL for the two groups were analyzed.

RESULTS

The amounts of IBL, 24-h BL, total input red blood cell, and the incidence of disseminated intravascular coagulation were significantly lower in group B than in group A (P<0.05), and this difference was even more significant in the subgroup of placenta percreta (PAS scores ≥10). Further multivariate linear analysis showed that the combined therapy of AABO and tourniquet could independently predict lower IBL than normal operative procedures did (P=0.001).

CONCLUSION

AABO combined with tourniquet binding of the LUS could improve the outcomes of pregnant women with severe PAS and reduce serious peripartum complications of AABO.

Image Analysis Application of Motherwort Total Alkaloid Injection in the Treatment of Postabortion Hemorrhage

In order to reduce the possibility of postabortion hemorrhage leading to maternal death, the author studied the image analysis of postpartum hemorrhage based on Leonurus total alkaloid injection, combining research results, in order to explore the curative effect of Leonurus injection in treating postpartum hemorrhage. After treatment, the time and volume of vaginal bleeding were significantly lower than those in the control group (P < 0.05); it is suggested that the combination of oxytocin and motherwort can effectively reduce the time and volume of vaginal bleeding after medical abortion, conducive to postoperative recovery. The results show that motherwort injection can effectively reduce the amount of bleeding and reduce the risk of postpartum hemorrhage; in addition, adverse reactions have been reduced, and an image analysis consensus has been formed, which is worthy of promotion.

The zone II aorta is not a forbidden zone for occlusion in women with morbidly adherent placenta

AIM

To evaluate the safety and efficacy of balloon occlusion at the Zone II aorta for the management of morbidly adherent placenta.

METHODS

From September 2015 to October 2018, a total of 80 consecutive patients who were prenatally diagnosed with morbidly adherent placenta were assigned into two groups: the balloon occlusion group (n = 40) and the non-balloon occlusion group (n = 40).The intraoperative estimated blood loss, blood transfusion, urine output, serum creatinine, blood urea nitrogen and hysterectomy rate were recorded and compared between the two groups.

RESULTS

The estimated blood loss in the balloon occlusion group was significantly lower than that in the non-balloon occlusion group (811.75 ± 299.93 ml vs 1529.75 ± 808.01 ml, P < 0.001). The median amount of packed RBCs transfused in the balloon occlusion group and non-balloon occlusion group was 0 U and 2 U, respectively (P = 0.001). The women in the former group had a lower blood transfusion rate than those in the latter group (30% vs 57.5%, P = 0.013). Hysterectomy occurred in none in the balloon occlusion group but in six patients in the non-balloon occlusion group (P = 0.011).

CONCLUSION

The middle abdominal aorta (Zone II) is not a forbidden zone for occlusion as long as the single occlusion time is limited to 15 min. Balloon occlusion at the Zone II aorta can effectively reduce blood loss, transfusion requirements and hysterectomy rates in patients with morbidly adherent placenta.

Combined Efficacy of Balloon Occlusion and Uterine Artery Embolization on Coagulation Function in Patients with High-Risk Placenta Previa during Cesarean Section

PURPOSE

The present study was performed in order to investigate the conbined effect of balloon occlusion and uterine artery embolization on coagulation function in patients with high-risk placenta previa during cesarean section.

METHODS

There involved a total of 38 patients with high-risk placenta previa undergoing cesarean section in our hospital from August 2019 to January 2021. The patients enrolled were randomly divided into study group (19 cases, receiving balloon occlusion combined with uterine artery embolization) and control group (19 cases, receiving conventional cesarean section). The operation time, intraoperative blood loss, plasma injection volume and hospital stay of the two groups were recorded. Moreover, the postoperative coagulation function indexes, including thrombin time (TT), fibrinogen (FBI), activated partial thromboplastin time (APTT) and prothrombin time (PT), were monitored and compared. Neonatal Apgar score and postoperative complications of the two groups were regarded as parameters for comparison.

RESULTS

The intraoperative blood loss, plasma injection volume and hospital stay of the study group were significantly lower compared with the control group (P < 0.05), whereas the operation time of the two groups was comparable (P > 0.05). Compared with the control group, the levels of TT, APTT and PT were lower while the level of FBI was higher in the study group (P < 0.05). The Apgar 1-min and 5-min scores of newborns were compared between the two groups (P > 0.05). However, the incidence of postoperative complications in the study group showed evidently lower outcomes compared with the control group (P < 0.05).

CONCLUSION

The combined approach of balloon occlusion and uterine artery embolization offered potential for improving the coagulation function of patients with high-risk placenta previa during cesarean section. In addition, the approach reduced the amount of blood loss and plasma injection, shortened the length of hospital stay, which was believed available for wide clinical application.

Postpartum hemorrhage - what the interventional radiologist should know

Postpartum hemorrhage is a leading cause of maternal morbidity and mortality around the world and can be caused by multiple etiologies. Distinguishing between the various etiologies that lead to PPH and identifying high risk features are crucial to implementing effective clinical management. In this review, the diagnostic imaging features and management principles of some of the most important causes of postpartum hemorrhage are discussed, with an emphasis on the pearls and pitfalls when minimally invasive treatment via interventional radiologic techniques are employed.

Number and quality of randomized controlled trials in obstetrics published in the top general medical and obstetrics and gynecology journals

BACKGROUND

There has been an increasing number of randomized controlled trials published in obstetrics and maternal-fetal medicine to reduce biases of treatment effect and to provide insights on the cause-effect of the relationship between treatment and outcomes.

OBJECTIVE

This study aimed to identify obstetrical randomized controlled trials published in top weekly general medical journals and monthly obstetrics and gynecology journals, to assess their quality in reporting and identify factors associated with publication in different journals.

STUDY DESIGN

The 4 weekly medical journals with the highest 2019 impact factor (New England Journal of Medicine, The Lancet, The Journal of the American Medical Association, and British Medical Journal), the top 4 monthly obstetrics and gynecology journals with obstetrics-related research (American Journal of Obstetrics & Gynecology, Ultrasound in Obstetrics & Gynecology, Obstetrics & Gynecology, and the British Journal of Obstetrics and Gynaecology), and the American Journal of Obstetrics & Gynecology Maternal-Fetal Medicine were searched for obstetrical randomized controlled trials in the years 2018 to 2020. The primary outcome was the number of obstetrical randomized controlled trials published in the obstetrics and gynecology journals vs the weekly medical journals and the percentage of trials published, overall and per journal. The secondary outcomes included the proportion of positive vs negative trials overall and per journal and the assessment of the study characteristics of published trials, including quality assessment criteria.

RESULTS

Of the 4024 original research articles published in the 9 journals during the 3-year study period, 1221 (30.3%) were randomized controlled trials, with 137 (11.2%) randomized controlled trials being in obstetrics (46 in 2018, 47 in 2019, and 44 studies in 2020). Furthermore, 33 (24.1%) were published in weekly medical journals, and 104 (75.9%) were published in obstetrics and gynecology journals. The percentage of obstetrical randomized controlled trials published ranged from 1.5% to 9.6% per journal. Overall, 34.3% of obstetrical trials were statistically significant or "positive" for the primary outcome. Notably, 24.8% of the trials were retrospectively registered after the enrollment of the first study patient. Trials published in the 4 weekly medical journals enrolled significantly more patients (1801 vs 180; P<.001), received more often funding from the federal government (78.8% vs 35.6%; P<.001), and were more likely to be multicenter (90.9% vs 42.3%; P<.001), non-United States based (69.7% vs 49.0%; P=.03), and double blinded (45.5% vs 18.3%; P=.003) than trials published in the obstetrics and gynecology journals. There was no difference in study type (noninferiority vs superiority) and trial quality characteristics, including pretrial registration, ethics approval statement, informed consent statement, and adherence to the Consolidated Standards of Reporting Trials guidelines statement between studies published in weekly medical journals and studies published in obstetrics and gynecology journals.

CONCLUSION

Approximately 45 trials in obstetrics are being published every year in the highest impact journals, with one-fourth being in the weekly medical journals and the remainder in the obstetrics and gynecology journals. Only about a third of published obstetrical trials are positive. Trials published in weekly medical journals are larger, more likely to be funded by the government, multicenter, international, and double blinded. Quality metrics are similar between weekly medical journals and obstetrics and gynecology journals.

Efficacy and safety of prophylactic abdominal aortic balloon occlusion versus internal iliac arterial balloon occlusion for placenta accreta spectrum disorder: A systematic review and meta-analysis

PURPOSE

To assess the efficacy and safety of abdominal aortic (AA) balloon occlusion versus internal iliac arteries (IIA) balloon occlusion in patients with placenta accreta spectrum (PAS) disorders.

METHODS

Databases of Embase, PubMed, Web of Science and Cochrane Library were systematically searched from inception to May 2020. The relevant literature was screened and the quality was assessed. RevMan software 5.3 was used to analyze the data.

RESULTS

Six studies involving 239 patients in AA occlusion and 281 patients in IIA occlusion were included. The results demonstrated that the intraoperative hemorrhage volume (MD - 410.61 ml, 95% CI -779.74 to -41.47 ml, p < 0.001), balloon dilatation duration (MD -5.34 min, 95% CI -9.91 to -0.77 min, p = 0.02) and fetus radiation dose (MD-20.81 mGy, 95% CI -31.84 to -9.78 mGy, p < 0.001) were significantly less in AA occlusion compared to IIA occlusion. There was no significant difference in the rate of lower extremity thrombosis between AA occlusion and IIA occlusion (OR 0.21, 95% CI 0.02 to 2.21, p = 0.19); similarly, no significant differences were found in blood transfusion volume (MD -344.50 ml, 95% CI -735.74 to 46.74 ml, p = 0.08), the rate of hysterectomy (OR 0.99, 95% CI 0.22 to 4.44, p = 0.99) and other outcome variables.

CONCLUSION

The available data demonstrated AA occlusion was more effective in reducing intraoperative hemorrhage volume and fetus radiation dose compared with IIA occlusion in patients with PAS disorders. Larger studies or randomized controlled trials are needed to further assert this evidence.

Prophylactic temporary abdominal aortic balloon occlusion for patients with pernicious placenta previa: a retrospective study

BACKGROUND

Pernicious placenta previa (PPP) can increase the risk of perioperative complications. During caesarean section in patients with adherent placenta, intraoperative blood loss, hysterectomy rate and transfusion could be reduced by interventional methods. Our study aimed to investigate the influence of maternal hemodynamics control and neonatal outcomes of prophylactic temporary abdominal aortic balloon (PTAAB) occlusion for patients with pernicious placenta previa.

METHODS

This was a retrospective study using data from the Peking University People's Hospital from January 2014 through January 2020. Clinical records of pregnant women undergoing cesarean section were collected. Patients were divided into two groups: treatment with PTAAB placement (group A) and no balloon placement (group B). Group A was further broken down into two groups: prophylactic placement (Group C) and balloon occlusion (group D).

RESULTS

Clinical records of 33 cases from 5205 pregnant women underwent cesarean section were collected. The number of groups A, B, C, and D were 17, 16, 5 and 12.We found that a significant difference in the post-operative uterine artery embolism rates between group A and group B (0% vs.31.3%, p = 0.018). There was a significant difference in the Apgar scores at first minute between group A and group B (8.94 ± 1.43 vs 9.81 ± 0.75,p = 0.037),and the same significant difference between two groups in the pre-operative central placenta previa (29.4% vs. 0%,p = 0.044), complete placenta previa (58.8% vs 18.8%, p = 0.032),placenta implantation (76.5% vs 31.3%, p = 0.015). We could also observe the significant difference in the amount of blood cell (2.80 ± 2.68vs.10.66 ± 11.97, p = 0.038) and blood plasma transfusion (280.00 ± 268.32 vs. 1033.33 ± 1098.20, p = 0.044) between group C and group D. The significant differences in the preoperative vaginal bleeding conditions (0% vs 75%, p = 0.009), the intraoperative application rates of vasopressors (0% vs. 58.3%, p = 0.044) and the postoperative ICU (intensive care unit) admission rates (0% vs. 58.3%, p = 0.044) were also kept.

CONCLUSIONS

PTAAB occlusion could be useful in reducing the rate of post-operative uterine artery embolism and the amount of transfusion, and be useful in coping with patients with preoperative vaginal bleeding conditions, so as to reduce the rate of intraoperative applications of vasopressors and the postoperative ICU (intensive care unit) admission. In PPP patients with placenta implantation, central placenta previa and complete placenta previa, we advocate the utilization of prophylactic temporary abdominal aortic balloon placement.

Experience of Managing Suspected Placenta Accreta Spectrum with or without Internal Iliac Artery Balloon Occlusion in Two Lithuanian University Hospitals

Background and objectives: Placenta previa and placenta accreta spectrum are considered major causes of massive postpartum hemorrhage. Objective: To determine whether the placement of an occlusion balloon catheter in the internal iliac artery could reduce bleeding and other related complications during cesarean delivery in patients with placenta previa and placenta accreta spectrum. Materials and Methods: A retrospective analysis was conducted at two tertiary obstetric units of Lithuania. From January 2016 to November 2019 patients with placenta previa and antenatally suspected invasive placenta were included in the intervention group and underwent cesarean delivery with endovascular procedure. From January 2014 to December 2015 patients with placenta previa and suspected placenta accreta spectrum were included in the non-intervention group. The primary outcomes were reduction in intraoperative blood loss and transfusion volumes in the intervention group. Secondary outcomes were the incidence of hysterectomy and maternal complications. Results: Nineteen patients underwent cesarean delivery with preoperative endovascular procedure, and 47 women underwent elective cesarean delivery. The median intraoperative blood loss (1000 (400–4500) mL vs. 1000 (400–5000) mL; p = 0.616) and the need for red blood cell transfusion during operation (26% vs. 23%; p = 0.517) did not differ significantly between the patients groups. Seven patients in the intervention group and two patients in the non-intervention group underwent perioperative hysterectomy (p = 0.002). None of the patients had complications related to the endovascular procedure. Conclusion: The use of intermittent balloon occlusion catheter in patients with placenta pathology is a safe method but does not significantly reduce intraoperative blood loss during cesarean delivery.

The intraoperative use of internal iliac artery balloon catheters in cesarean deliveries for abnormal invasive placentation: A 3-year retrospective cohort review in Doha, Qatar

Background: Abnormal invasive placentation leads to massive intraoperative hemorrhage and maternal morbidity. This study aimed to assess the impact of the preoperative use of internal iliac artery balloon occlusion (IIABO) catheters in patients who had a cesarean delivery (CD) for invasive placentation, commonly known as the placenta accreta spectrum.

Methods: This retrospective cohort study reviewed 67 pregnancies complicated by abnormal invasive placenta and confirmed intraoperatively. Preoperative planned placement of IIABO was performed in 33 women who underwent elective CD. Senior Obstetricians with the necessary expertise performed all CDs. The primary outcome measures were: intraoperative blood loss, blood transfusion requirement, duration of surgery and the need for hemostatic measures. Univariate comparison between the groups and regression analysis of the primary outcome and controlling for confounders, were performed.

Results: No statistically significant difference was observed between the groups with intraoperative hemorrhage volume of above 3000 mL (unadjusted odds ratio [OR] 0.94 [no-IIABO group as the reference]; p = 0.895) and the median duration of surgery (median 107, interquartile range [IQR] 80–135 vs. median 96, IQR 75–121; p = 0.3508). More than 40% of the IIABO group required intraoperative transfusion of packed red blood cells above six units (14 [42.4%] vs. 10 [29.4%]; p = 0.357]), and 30% required additional postoperative transfusion (10 [30.3%] vs. 8 [23.5%]; p = 0.706]), although not statistically significant. Multivariate logistic regression analysis showed that the difference remained nonsignificant after covariate adjustment (adjusted OR 0.585, p = 0.456). Cesarean hysterectomy was performed in fewer cases (seven [21.1%]) in the IIABO group than in the no-IIABO group (10 [29.4%]), although this difference was not significant (unadjusted OR 0.65, p = 0.442).

Conclusions: The placement of IIABO catheters is an invasive procedure, which consumes time and resources. Its value as a means of reducing intraoperative blood loss or preserving the uterus in patients with abnormal placental adherence appears questionable. In this cohort study, there was no statistical difference in blood loss, and the need for other steps to control hemorrhage between women with and without IIABO catheters.

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

Placenta accreta spectrum (PAS) is a leading contributor to major obstetric hemorrhage and severe maternal morbidity in the developed world. In the United States, PAS has become the most common cause of peripartum hysterectomy. Over the last 40 years, clinicians have also witnessed a dramatic increase in the incidence of PAS. In the 1950s, the incidence of PAS was reported to be 0.03 per 1000 pregnancies. Recent epidemiological studies estimate that the PAS incidence is between 0.79 and 3.11 in 1000 pregnancies. As a consequence, obstetric anesthesiologists are increasingly likely to be called upon to manage women with suspected PAS for delivery. Given the increasing incidence and the morbidity burden associated with PAS, anesthesiologists play a vital role in optimizing maternal outcomes for women with PAS. This review will provide up-to-date information on nomenclature, pathophysiology, risk factors, antenatal detection, systemic preparations (includes timing of delivery, location of surgery, pre-operative evaluation and patient positioning), surgical and anesthetic approach, intra-operative management, invasive radiology and postoperative plans.

The effect prophylactic internal iliac artery balloon occlusion in patients with placenta previa or placental accreta spectrum: a systematic review and meta-analysis

BACKGROUND

Placenta previa describes a placenta that extends partially or completely over the internal cervical oss. Placenta previa is one of the leading causes of widespread postpartum hemorrhage and maternal mortality worldwide. Another cause of bleeding in pregnant women is Placenta accreta spectrum. Therefore, the aim of the present systematic review and meta-analysis is to determine the effect of prophylactic balloon occlusion of the internal iliac arteries in patients with placenta previa or placental accreta spectrum (PAS).

METHODS

In this systematic review and meta-analysis, to identify and select relevant studies, the SID, MagIran, ScienceDirect, Embase, Scopus, PubMed, Web of Science, and Google Scholar databases were searched, using the keywords of internal iliac artery balloon, placenta, previa, balloon, accreta, increta and percreta, without a lower time limit and until 2020. The heterogeneity of the studies was examined using the I² index, and subsequently a random effects model was applied. Data analysis was performed within the Comprehensive Meta-Analysis software (version 2).

RESULTS

In the review of 29 articles with a total sample size of 1140 in the control group, and 1225 in the balloon occlusion group, the mean difference between the two groups was calculated in terms of Intraoperative blood loss index (mL) and it was derived as 3.21 ± 0.38; moreover, in 15 studies with a sample size of 887 in the control group, and 760 in the balloon occlusion group, the mean difference between the two groups in terms of gestation index (weeks) was found as 2.84 ± 0.49; and also with regards to hysterectomy balloon occlusion after prophylactic closure of the iliac artery, hysterectomy (%) balloon occlusion was calculated as 8.9 %, and this, in the hysterectomy control group (%) was obtained as 31.2 %; these differences were statistically significant and showed a positive effect of the intervention (P < 0.05).

CONCLUSION

The results of this study show that the use of prophylactic internal iliac artery balloon occlusion in patients with placenta previa or Placenta accreta spectrum has benefits such as reduced intraoperative blood loss, reduced hysterectomy and increased gestation (weeks), which can be considered by midwives and obstetricians.

Factors Affecting the Risk of Postpartum Hemorrhage in Pregnant Women in Tibet Health Facilities

BACKGROUND Postpartum hemorrhage (PPH), the leading cause of maternal death, is defined as a blood loss >500 mL within 24 h after vaginal delivery or >1000 mL within 24 h after cesarean section. This study aimed to investigate the incidence of PPH and assess its risk factors in pregnant women in Tibet to provide a reference for clinicians in this region. MATERIAL AND METHODS A total of 4796 pregnant women with gestational age ≥28 weeks who were admitted to hospitals in Tibet between December 2010 and December 2016 were involved in this study. Patient sociological and clinical data and pregnancy outcomes were collected. The related risk factors of PPH were analyzed by univariate and multivariable logistic regression. The area under the curve of the receiver operating characteristic curves was used to evaluate the effect of the PPH prediction model. RESULTS PPH occurred in 95 women, with an incidence of 1.98%. The following factors were associated with higher risk for PPH: maternal age ≥35 (odds ratio [OR]=1.96; 95% confidence interval [CI], 1.18-3.27; P=0.010), history of preterm birth (OR=2.66; 95% CI, 1.60-4.42; P<0.001), cesarean section (OR=6.69; 95% CI, 4.30-10.40; P<0.001), neonatal weight >4 kg (OR=3.92; 95% CI, 1.75-8.81; P<0.001) and occurrence of neonatal asphyxia (OR=5.52; 95% CI, 2.22-13.74; P<0.001). CONCLUSIONS Maternal age ≥35, history of preterm birth, cesarean section, newborn weight >4 kg, and neonatal asphyxia were risk factors of PPH, which can help evaluate PPH in Tibet.

Effect of types of placenta previa on maternal and neonatal outcomes: a 10-year retrospective cohort study

PURPOSE

Through this study, we aimed to evaluate the effects of different types of placenta previa (PP) on maternal and neonatal outcomes.

METHODS

This study was conducted in The Third Affiliated Hospital of Guangzhou Medical University and Tongji Hospital between January 2009 and 2019. PP was traditionally classified into four types, namely low-lying placenta, marginal, partial, and complete PP. Previous studies have classified PP into two types, namely low-lying placenta and PP. Based on our clinical experience, we proposed the classification of PP into three types, for the first time, which included low-lying placenta, "marpartial" (marginal and partial) PP, and complete PP. Multivariate logistic regression analysis was performed to determine the effects of different types of PP on maternal and neonatal outcomes.

RESULTS

In total, 4490 singleton pregnancies were complicated with PP. In the four-classification method, compared with women with low-lying placenta, women with complete PP had a risk of placenta accrete spectrum disorders, postpartum hemorrhage (PPH), hemorrhagic shock, severe PPH, blood transfusion, hysterectomy, puerperal infection, preterm labor, NICU admission, and low birth weight. There was no difference in maternal and neonatal outcomes between marginal and partial PP, except for increased chances of preterm labor and low birth weight in partial PP. In the two-classification method, PP was the risk factor for most of the adverse maternal and neonatal outcomes, compared with low-lying placenta.

CONCLUSION

Complete PP and low-lying placenta were associated with the highest and lowest risks of adverse pregnancy outcomes, respectively, whereas clinically similar outcomes were observed between marginal and partial PP. The three-classification of PP may be practical from the clinical perspective.