The role of interventional radiology in primary postpartum hemorrhage

Endometritis risk factors after arterial embolisation for postpartum haemorrhage

Various complications of arterial embolisation (AE) for postpartum haemorrhage (PPH) are reported. Endometritis (EM) frequently causes abscesses, increasing hysterectomy risk. However, risk factors for EM after AE for PPH are unclear. We explored these risk factors. We included patients who underwent AE for PPH in our hospital from 2005 to 2020 and compared those who did (EM group) and did not develop EM after AE (non-EM group) in a case-control study. Twenty patients met the study criteria; eight patients (40%) had EM. There were no differences in risk factors between groups involved in infection, such as premature rupture of membranes. However, the contrast medium extravasation rate on computed tomography scans before the AE procedure was significantly higher in the EM group (p=.019) compared to the non-EM group. The greatest EM risk factor was contrast medium extravasation before AE for PPH, determined by classification and regression tree modelling (relative risk: 4.5).Impact StatementWhat is already known on this subject? Reportedly, the clinical success rate of arterial embolisation (AE) for critical haemorrhage in obstetrics is high, around 90%. However, information regarding AE complications is limited. Endometritis is one of these complications, which not only causes prolonged hospitalisation but may also require further treatment, such as hysterectomy. However, the incidence rate and risk factors for EM remain unknown.What do the results of this study add? In this study, 40.0% of patients developed EM after AE for PPH. Extravasation of contrast medium was the top risk factor (relative risk: 4.5 compared to those without EM, p=.019). The second-leading risk factor was a bleeding volume greater than 2500 mL (relative risk: 4.5 compared to those without EM, p=.019).What are the implications of these findings for future clinical practice and/or future research? We created an EM prediction model using extravasation and a bleeding volume greater than 2500 mL. The model was 87.5% sensitive and 66.7% specific. This prediction model allows for the early detection and treatment of EM by recognising high-risk patients and providing intensive postpartum management.

Risk Factors Associated with Clinical Failure of Uterine Artery Embolization for Postpartum Hemorrhage

PURPOSE

To identify risk factors for clinical failure of uterine artery embolization (UAE) for postpartum hemorrhage (PPH), with particular attention to the uterine artery diameter.

MATERIALS AND METHODS

This retrospective study included 47 patients who underwent UAE for PPH between January 1, 2010, and January 31, 2021. Technical success was defined as the completion of embolization of the arteries thought to be the cause of the bleeding. Clinical success was defined as no recurrent bleeding or need for additional therapeutic interventions. Univariate and multivariate analyses were performed to examine the risk factors associated with clinical failure of UAE.

RESULTS

Of the 47 patients, 6 had recurrent bleeding. Of the 6 patients, 4 underwent hysterectomy, and 2 underwent repeat embolization. The clinical success rate was 87.2% (41/47), with no major adverse events such as uterine infarction or death. In univariate analysis, there were slight differences in multiparity (P = .115) and placental abruption (P = .128) and a significant difference in the findings of a narrow uterine artery on digital subtraction angiography (DSA) (P = .005). In multivariate analysis, only a narrow uterine artery on DSA was a significant factor (odds ratio, 18.5; 95% confidence interval, 2.5-134.8; P = .004).

CONCLUSIONS

A narrow uterine artery on DSA was a risk factor for clinically unsuccessful UAE for PPH. It may be prudent to conclude the procedure only after it is ensured that vasospasm has been relieved.

Two Case Studies on Inferior Mesenteric Artery Embolization for Primary Postpartum Hemorrhage

Postpartum hemorrhage (PPH) remains a leading cause of maternal mortality. Transcatheter arterial embolization (TAE) is an effective treatment option for PPH. Among the vessels embolized, the inferior mesenteric artery (IMA) is usually not the first choice for TAE, because it is a rare source of bleeding in PPH. In this report, we describe our experience with two patients with PPH, in whom the IMA was selected on the basis of contrast-enhanced computed tomography (CECT) findings, and prompt hemostasis was achieved with TAE. CECT can provide useful clues as to the culprit artery based on the anatomical location of the hematoma and extravasation. These useful findings of CECT allow prompt TAE of rare sources of bleeding in PPH, such as the IMA.