Postpartum hemorrhage (PPH) continues to challenge obstetric care despite ongoing medical advancements. With blood loss exceeding 500 ml in 6.3% to 13% of births and over 1000 ml in 1.9% to 2.8% of cases, PPH remains a significant concern. These figures are particularly worrying given that 500 ml is the established threshold for PPH following vaginal delivery. Cesarean sections often involve even more significant blood loss, frequently exceeding 1000 ml.
This raises critical questions about the risks we’ve come to accept in modern obstetric practice. How can understanding the significant blood loss associated with delivery reshape our management strategies? Given the advancements in minimally invasive techniques, how can we incorporate novel approaches to enhance patient safety and outcomes during deliveries? This article explores how endovascular surgery fits in the multidisciplinary approach to PPH.
The Growing Threat of Placenta Accreta Spectrum
A key contributor to PPH is the placenta accreta spectrum (PAS), where the placenta attaches too deeply to the uterine wall. This condition involves complex cellular interactions that we’re still working to fully understand. The resulting deep attachment can cause severe bleeding during delivery, posing substantial risks to maternal health.
The link between cesarean deliveries and PAS is particularly concerning. Cesarean sections disrupt the natural structure of uterine tissue, leading to scarring that can complicate future pregnancies. This microscopic change in uterine structure can lead to significant complications with potentially serious consequences. Studies consistently show that the more cesarean deliveries a woman has, the higher her risk of developing PAS.
The prevalence of PAS has increased dramatically, now affecting approximately 1 in 533 pregnancies. This rise closely mirrors the increasing rate of cesarean deliveries. Understanding this relationship is crucial to developing effective prevention and management strategies. It challenges us to balance the immediate benefits of cesarean sections with their potential long-term risks, a consideration that should inform both clinical decision-making and patient counseling.
Historical Endovascular Approaches
In the past, endovascular specialists employed various techniques to manage PPH either prophylactically or postpartum. Bilateral internal iliac artery occlusion was one of the earliest approaches, requiring balloon occlusion catheter placement in the internal iliac arteries. This technique, while pioneering, required precise catheter placement and bilateral femoral arterial access. The major disadvantage is that it fails to control the significant collateral circulation to the uterus and placenta from sources beyond the internal iliac arteries.
Uterine artery embolization (UAE) has also been proposed as an alternative. UAE is usually well-tolerated and feasible, making it suitable for hemodynamically stable patients experiencing slow, ongoing bleeding. The major disadvantage, however, is the permanence of arterial embolization, which can have implications on future fertility, with decreased blood flow to the uterus, and even the development of pelvic ischemia in rare cases.
Prophylactic Aortic Occlusion: A Preemptive Approach
Prophylactic balloon occlusion of the aorta is the newest technique for managing PPH, especially in high-risk patients, such as those with placenta accreta. This procedure involves strategically placing a balloon occlusion catheter in the abdominal aorta. It temporarily blocks blood flow to at-risk areas, significantly reducing blood loss during delivery. Recent studies show encouraging results with prophylactic aortic occlusion, suggesting it may be more effective than bilateral iliac artery occlusion or UAE for severe hemorrhage management. Research from Texas Children’s Hospital and Atrium Health suggests that prophylactic aortic occlusion can significantly reduce blood loss and transfusion requirements in high-risk patients. These hospitals exclusively use the COBRA-OS® (Front Line Medical Technologies, Canada), a 4 French aortic occlusion device, that aims for improved safety than previous aortic occlusion devices. This prophylactic approach may ultimately lead to reducing the need for unplanned surgical interventions like hysterectomy.
REBOA Technology: A Closer Look
The COBRA-OS® is part of a broader category of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) technology. While REBOA has shown promise in managing severe hemorrhage, its implementation has been challenging in the past, mainly due to a 7-8% access complication rate using previous 7 French devices. The 4 French COBRA-OS® aims to address these challenges, potentially making this life-saving technology safer and more accessible.
Dr. Adam Power, co-founder of Front Line Medical Technologies and a practicing vascular surgeon, explains the device’s design philosophy: “Helping mothers survive high-risk deliveries is a major focus of our company with the innovative COBRA-OS®. In female patients who are at higher risk of clotting due to pregnancy and who have smaller arteries, it is critical to use a low-profile aortic occlusion device to avoid the complications seen with larger devices.”
This focus on the unique physiological changes of pregnancy demonstrates a thoughtful approach to medical device design. By considering the specific needs of postpartum patients, the COBRA-OS® aims to provide a more tailored and potentially safer intervention option.
Conclusion
Addressing PPH, particularly in cases involving the PAS, demands a coordinated effort from a diverse team of medical professionals. Only when obstetricians, endovascular specialists, anesthesiologists, and critical care specialists work closely together can we maximize the potential of tools like the COBRA-OS®.
Medical innovations provide new ways to address PPH, a condition that remains one of the leading causes of maternal mortality worldwide. Although the road from breakthrough technology to becoming a standard of care can be lengthy and complex, devices like the COBRA-OS® give us a glance at how targeted solutions can make a real difference.
The reality is that these advancements present a critical opportunity to save lives and improve maternal care. Ultimately, the goal is to reduce the risks women face during childbirth, but also to make childbirth safer and less stressful for mothers and their families.
References:
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- https://www.prweb.com/releases/front-line-medical-technologies-announces-the-release-of-first-real-world-data-of-the-cobra-os-for-postpartum-hemorrhage-301972775.html