Uro-catheter Vacuum-induced Uterine Tamponade (U-CaVIT) Versus Standard of Care for Prevention of Atonic Postpartum Hemorrhage After Cesarean Section in High-risk Women: a Monocentric Randomized-controlled Pilot Study.

Postpartum hemorrhage (PPH) is the main reason for maternal peripartum mortality and morbidity. It poses a significant burden not just in developing countries but also in industrialized nations, where an upward trend in PPH-related problems is being observed.

According to the WHO, PPH is defined as blood loss of 500 mL or more within 24 hours after delivery, and it causes about 30% of maternal deaths worldwide. The internationally observed trend towards increased PPH-related morbidity and mortality is disturbing and demands new strategies in the prevention and treatment of PPH.

The underlying causes of PPH are uterine atony (Tonus), trauma (Trauma), placental disorders (Tissue), and coagulopathy/hemorrhagic diathesis (Thrombin) as well as disorder of the coagulation system which itself aggravates bleeding. Among these, uterine atony, which prevents mechanical hemostasis, is thought to be responsible for 60-80% of PPH cases and remains one of the most frequent causes of postpartum hysterectomy.

Therapy of uterine atony is based on the use of uterotonic drugs, nonsurgical approaches (e.g., uterine massage, intrauterine tamponade with an intrauterine balloon, vacuum device, or packing) as well as surgical therapies (e.g., repair of a deep laceration or tear in the uterus, cervix, or vagina; uterine artery ligation; curettage; uterine compression sutures; hysterectomy). A reasoned and sequential treatment approach is based on a multistage strategy that starts from less invasive interventions proceeding to more invasive methods. The strategic goal is to prevent severe PPH by implementing a minimally invasive, effective and low-cost method at an early stage of PPH or even before PPH might occur in high-risk patients, who inherently have an increased bleeding risk following a cesarean section. This would result in an enormous benefit to the patient in terms of morbidity and mortality as well as a consistent and judicious approach in the use of resources.

In an atonic uterus, vessels are not constricted and hemorrhage ensues, prompting first-line therapy. When medical management alone is deemed unsuccessful, balloon tamponade is currently the next treatment option added to control uterine atony. A balloon is placed within the uterus and inflated with sterile saline solution to put sustained pressure on the uterus from the inside. The Bakri® Balloon (Cook Medical) is currently the most commonly described intrauterine tamponade balloon device in the literature. By applying external pressure to the uterine walls for 12-24 hours, the uterus may then involute and regain normal tone. Although tamponade has been demonstrated to be effective in controlling hemorrhage in 87% (95% CI 84-90%) of atony-related cases, the mechanism of action of using outward pressure to control bleeding from uterine atony is counterintuitive if the ultimate goal is uterine contraction.