The Cardiovascular Interventional Radiological Society of Europe (CIRSE) 2020 Standards of Practice document for gynaecological and obstetric haemorrhage are among the most comprehensive guidelines in interventional radiology (IR) for obstetric interventions. The guidelines cover the use of IR for both elective and emergency procedures. The indications for IR are for postpartum haemorrhage and post-surgical bleeding in the emergency setting, and electively for the embolization of tumours either as a primary treatment or as an adjunct to surgery; embolization for arteriovenous fistulae and malformations; and the elective use of prophylactic occlusion balloons in abnormal placentation.
The guidelines cover the basics of anatomical knowledge required to perform an effective embolization. The operator must be aware of potential causes of failure of embolization including failure to search for and treat collateral supply to the uterus. Recommendations are made for appropriate imaging equipment which should ideally consist of an IR or hybrid theatre setting with digital subtraction angiography. However, it is recognised that lifesaving embolization may be required and can be performed successfully in an obstetric theatre using portable image intensifiers. In such non-optimal settings, the operator must be aware of the higher potential for non-target embolization secondary to poor visualisation. The guidelines also suggest having available an ‘emergency haemorrhage control box’ which would have all the essential equipment needed to provide this procedure in a setting remote to the IR suite.
Active extravasation is only seen in 21–52% of cases and is mostly seen with uterine atony. In most cases of postpartum haemorrhage, a focal bleeding point is not identified. It is important in this situation to perform bilateral empirical embolization of the uterine arteries. The embolic agent of choice in this situation is absorbable gelatine sponge. This allows for later recanalization of the artery when it has healed. In an emergency, patients usually require rapid catheter angiography and embolization. However in a more elective situation, for example where there is a slow bleed, but the patient is not unstable, a triple phase computed tomography (CT) scan may be useful in identifying a source of bleeding, thus enabling targeted embolization. If focal bleeding points are identified, for example, a pseudoaneurysm, permanent embolic agents can be used, such as coils. The choice of embolic agent is dependent on operator expertise and availability.
Approximately 5–10% of patients undergoing embolization may re-bleed. Causes of failure of embolization include development of arterial spasm, collateralisation after primary embolization of the uterine arteries, bleeding from non-uterine artery sources, previous surgical ligation or dilatation and curettage, unilateral embolization, and abnormal placentation. Potential complications from embolization include non-target embolization resulting in limb and buttock claudication, and necrosis of structures with pelvic arterial supply. These risks can be mitigated by using high-quality imaging, avoiding the use of very small particles, and being aware of collateral and cross-uterine blood supply.
The placement of prophylactic occlusion balloons in the management of patients with abnormally adherent placenta is also becoming more commonplace with the increase in incidence of abnormally adherent placenta and this is also discussed briefly in the guidelines.
Postpartum haemorrhage remains the leading cause of maternal morbidity and mortality worldwide. In 2015, postpartum haemorrhage was reported to be responsible for more than 80,000 maternal deaths worldwide. The use of embolization in the treatment of obstetric haemorrhage was first reported in the 1970s. Since then, the use of IR in the treatment of both elective and emergency haemorrhage has increased and the success rates of embolization for postpartum haemorrhage are reported as being between 79% and 100%. Despite this, the rates of hysterectomy remain high and the use of IR for the treatment of postpartum haemorrhage is still significantly underutilised. Much more needs to be done to promote the availability and access to IR for patients. CIRSE’s 2020 guidelines and the 2022 International Federation of Gynaecology and Obstetrics guidelines both recommend the use of IR after failure of conservative measures to control haemorrhage, and before contemplating surgery. We need to move beyond these guidelines to make this a reality in practice for patients.
Lakshmi Ratnam is a consultant diagnostic and interventional radiologist at St George’s University Hospitals NHS Foundation Trust in London, UK.
Disclosures: The author declared no relevant disclosures.
