In the present study, we showed that in the patients with postpartum haemorrhage, the sensitivity of detecting arterial extravasation on CE-CT scanning was 100% and the negative predictive value was also 100%. It is important to identify the source of bleeding when planning a haemostatic strategy. In the case of arterial bleeding, there are options other than surgery as a haemostatic strategy, such as uterine artery embolization. Therefore, this study, which showed for the first time, to our knowledge, the accuracy of CE-CT scanning in postpartum haemorrhage, may be useful in planning strategies to treat postpartum haemorrhage.
To our best knowledge, there are no reports of the accuracy of detecting arterial extravasation on CE-CT scanning in postpartum patients, but there are many reports of its utility in severe trauma patients. Salimi et al. reported that the sensitivity of CE-CT scanning for intra-abdominal organ injury was 100% for liver injury and 86.6% for splenic injury [12]. Dreizin et al. reported that the sensitivity and specificity of CE-CT scanning to search for arterial bleeding in pelvic trauma were 80% and 93%, respectively [13]. Because the presence of arterial injury can be identified by extravasation on CE-CT scanning, CE-CT scanning can rapidly identify the site of injury in parenchymal organ injury and pelvic trauma [14]. Thus, the identification of arterial extravasation with CE-CT scanning in trauma is a useful diagnostic tool due to its high sensitivity and negative predictive value [15]. In the present study, the identification of arterial extravasation on CE-CT scanning was highly sensitive in postpartum haemorrhage, and its presence on CE-CT imaging may be useful as a screening test to detect arterial bleeding in postpartum patients.
The presence of arterial bleeding is important in planning a treatment strategy because treatment options such as trans-catheter arterial embolization (TAE) are available in addition to surgical treatment. According to the Eastern Association for Surgery of Trauma guidelines, when the cause of bleeding is intra-abdominal haemorrhage or intra-abdominal organ damage, TAE is a treatment option as long as the patient’s vital signs are stable [4]. Furthermore, when the cause of bleeding is retroperitoneal haemorrhage such as from pelvic fracture, TAE is the first choice for bleeding control, even if the patient’s vital signs are unstable [16]. Kuo et al. reported that in trauma with haemorrhagic shock, there were cases requiring TAE among those who did not initially show extravasation on CE-CT scanning. They reported that in patients with pelvic fractures, 19.5% (30/154) of those without extravasation on CE-CT scanning underwent TAE, and these patients were accompanied by hypotension (extravasation (+) vs. extravasation (-); 68 mmHg vs. 129 mmHg [median]) on hospital arrival [17]. However, the effectiveness of uterine artery embolization for postpartum haemorrhage has also been noted in several studies [18], but the rapid identification of the source of bleeding is essential in the case of critical postpartum haemorrhage. Intraperitoneal and retroperitoneal haemorrhage can occur in postpartum haemorrhage, and in the present study, the sensitivity of detecting arterial extravasation with CE-CT scanning in postpartum haemorrhage was 100% not only in the patients with shock but also in those without shock.
Surgery is the first choice for haemostatic treatment in critical trauma patients whose vital signs are unstable. Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a technique used to control subdiaphragmatic bleeding. REBOA is used as a damage control strategy for trunk trauma with haemorrhagic shock and also preoperatively and intraoperatively for surgery and transcatheter therapy. The efficacy of REBOA has been reported for postpartum haemorrhage with unstable circulation [19, 20]. In the present study, blood loss was highest in the group with extravasation on CE-CT and without angiography, (3820 g, IQR; 2000–6050 g), and 4 patients required hysterectomy for haemostatic treatment. Although the median SI in this group was 1.0, the condition of the patients required urgent haemostatic treatment via surgery. Hysterectomy cannot preserve fertility, but if REBOA can be used as a bridging therapy until angiography, it may be possible to preserve the uterus.