For bleeding with uterine atony in postpartum or cesarean section, various methods of hemostatic suture and balloon tamponade in the uterine body have been reported, including the B-lynch suture and Bakri-balloon [1, 2].
In placenta previa and accreta, heavy hemorrhaging is often encountered with gushing from the lower part of the uterus. This hemorrhaging is difficult to stop, and effective hemostatic methods are limited, especially for bleeding from the area around the internal uterine ostium. In such cases, conventional methods such as direct suturing, gauze filling, and uterine balloon tamponade were used, as in the case of uterine atony [9,10].
Meanwhile, compression sutures, in which the lower anterior and posterior uterine walls are compressed to stop bleeding, have also been reported [5,6]. A typical method of compression suturing on the lower segment of the uterus is the parallel vertical compression suture (PVCS), devised by Hwu et al. [5]. This suture penetrated the anterior wall of the lower uterus, but not the posterior wall, only through the muscle layer. On the other hand, Tanaka et al. [6] reported a full-thickness suture penetrating the anterior-posterior wall of the uterus. This allows the lower part of the uterus to be easily compressed to stop the bleeding. Furthermore, Li et al. [7] reported a method of revising the suturing position spanning over the uterine incision.
These compression sutures on the lower segment of the uterus are easy and quick to perform; however, some problems remain. First, compression sutures reduce the cavity of the lower uterus; therefore, if required, additional hemostatic measures are difficult to perform. In particular, gauze packing or Bakri-balloon tamponade can be difficult and inadequate, owing to narrowing of the cervix. Second, compression sutures involve extensive blockages of both the anterior and posterior walls of the lower uterus, which may have an adverse impact on subsequent pregnancy.
Finally, when the suture is placed too laterally to the uterus, it may damage the uterine artery, whereas when it is placed too close to the median, it may obstruct the cervical canal, resulting in poor evacuation of the lochia.
Considering the abovementioned details, we developed VUS as a simple and quick method to achieve hemostasis in placenta previa during laparotomy, which overcomes the disadvantages of PVCS. VUS is designed to be effective for hemostasis, even when the bleeding site involves the internal ostium, because direct sutures can be applied on the involved site.
We used a straight blunt needle to penetrate the uterine wall, developed by Matsuzaki et al.[8], which enabled minimal invasion of the fragile surface of placental detachment, due to the blunt needle, and easy control of the needle tip during penetration, due to the straight needle. Nonetheless, when performing VUS in clinical practice, it is not necessary to use this special, long needle. Unlike compression sutures which require a long needle in the case of VUS, the conventional needle is sufficient in size because only one side of the uterine wall is penetrated. This is an important clinical advantage of VUS.
Thus, VUS is characterized by suturing only one side of the lower uterine wall surrounding the bleeding site of the placental detachment. This is the first report of localized hemostatic suturing on the side of placental abruption that is sufficient for hemostasis in placenta previa and accreta.
The most commonly used parameter to assess the hemostatic efficacy of intraoperative procedures is estimated intraoperative blood loss. The mean estimated intraoperative blood loss in our 14 patients with VUS was 1212 ± 463 ml (range, 700-2100 ml). Furthermore, in the 12 singleton cases, the mean blood loss was even lower (1130 ± 429 ml). In five cases of total placenta previa, blood loss was <1500 ml in the present study. Blood transfusion was not required in any of the 14 patients.
In comparison with previous reports, the amount of estimated blood loss with VUS was less than that with other methods for placenta previa and accreta (Table 2). These results indicate that VUS is much more effective for hemostasis, with less intra-operative blood loss than conventional compression sutures.
As to placenta accrete, there were two cases in the present study. In Case 10, it took a few minutes to detach the placenta manually, and persistent bleeding occurred from the remaining placenta, which caused a large amount of bleeding (2100 ml). Notably, after VUS, bleeding stopped completely. In Case 14, as an empirical precaution, VUS was performed immediately on the remaining placenta, and the resultant blood loss was a usual amount of 750 ml. These results strongly suggest that even in placenta accreta, VUS is an effective technique for reducing intraoperative hemorrhaging.
Comparing with PVCS, the characteristics of VUS are summarized below.
1. Additional hemostatic measures are possible.
The internal cavity of the lower uterus is wider even after VUS; therefore, additional hemostatic measures, such as gauze packing, Bakri-balloon tamponade, and PVCS can be easily performed in cases of continued bleeding.
2. The area of blood blockage is localized compared to PVCS. In VUS, the suturing area is localized to one side of the uterine wall with the placental abruption. Therefore, the adverse effects caused by hypoperfusion or ischemic changes within the suturing area, such as wound thinning or suture failure, are less likely to occur during postoperative recovery.
3. It is possible to control the bleeding from the vicinity of the cervical canal. The lower end of the suture reaches the level of the internal uterine ostium, so that it can directly stop the refractory bleeding, which comes from the uterine cervix via the fine collateral channels from the vagina.
4. Ensured cervical patency and avoidance of artery insult. In VUS, the suture is placed on one side of the uterine wall and the needle is inserted away from the uterine artery. Accordingly, cervical patency is ensured and the uterine artery insult is avoidable, with VUS.
5. The suture area is adjustable. Whether the placenta is attached anteriorly, laterally, or posteriorly, VUS can be applied to stop bleeding, by shifting the position of the needle. Furthermore, VUS allows the upper end of the suturing area to be extended cephalad until cover the bleeding area completely,
There are few knacks on how VUS can be performed in practice. First, needle insertion of both the left and right threads at the level of the internal ostium should be performed at the same point in the midline. Second, the tip of the needle should be carried straight backwards, emerging at the midline of the posterior surface of the cervix (Figure 2). These techniques reduce bleeding from the vicinity of the internal ostium and prevent damage to the bilateral uterine arteries. Finally, it is better to perform VUS as early as possible after placental detachment, because, while the surgeon is debating whether to use VUS, bleeding increases and often reaches approximately >2000 ml. VUS is strongly recommended as the first-line treatment for active bleeding, immediately after placental detachment.
Regarding limitations, our study has a bias, which is the small sample size and lack of multivariate analysis to analyze the variable factors. Although the results of our study were superior to those of previous studies, it is necessary to collect more cases and perform multivariate analysis to accurately analyze the effect of VUS.
The present retrospective study focused on the suturing technique. The strength of the present study is that this is the first report of VUS, which is a new technique and an alternative to compression uterine suture, resulting in the least amount of blood loss compared to previous reports
Hemostatic suturing of the bleeding area is a basic clinical procedure and VUS was performed within the scope of this basic technique to stop bleeding in the lower part of the uterus. In addition, compression sutures, which include extensive compression area, are already recognized clinically. Therefore, this minimally invasive VUS is considered clinically necessary and appropriate.
We conclude that VUS is a simple and quick suturing technique with minimal blockage for the control of continuous bleeding in placenta previa or accreta that does not obliterate the lower uterine space and allows for additional hemostatic procedures in laparotomy. We suggest that VUS should be attempted first to obtain reliable hemostasis and prevent critical hemorrhagic damage.