Surgical Treatment of Early Postpartum Hemorrhage Caused by Lower Uterine Segment Atony

Purpose: Lower uterine segment atony is recently being recognized as one of the major reasons for early postpartum hemorrhage. Methods: We present our experience in surgical treatment of lower uterine segment atony patients that were delivered in our tertiary perinatal center during the 10 years period (2010-2019). Results: This particular study enrolled total number of 29 543 deliveries with 215 cases of early PPH (0,72%). LUSA was diagnosed in 44 cases or in 29,93% in all uterine atony cases. Exploration of the lower uterine segment accompanied by evacuation of the coagula was conducted in 5 cases (11,36%), haemostatic ligation procedures according to authors: Losickaja in 2 cases, Hebisch-Huch in 9 cases, Habek in 5 cases, Hebisch-Huch+Losickaja in 9 cases. Evacuation procedures were combined with ligation techniques in 7 cases, evacuation methods with ligation techniques and balloon tamponade in 2 cases, exploration combined with gauze tamponade in 1 case and ligation procedures with balloon tamponade in 3 cases. According to our results, haemostatic ligation procedures alone or combined with tamponade, have shown to be highly effective in 88,63%. Conclusion: Transvaginal approach for surgical treatment of lower uterine segment atony is accessible, feasible, successful and life saving. It can be easily performed in inpatient and outpatient care settings followed by administration of uterotonics, uterostiptics and tranexamic acid and uid replacement. All of the above mentioned methods are of great importance in the prevention and treatment of obstetric hemorrhagic shock, development of coagulopathy, multiorgan failure, postpartum hysterectomy and nally vital for fertility preservation.


Introduction
Early or primary postpartum hemorrhage (PPH) is besides of obstetric shock, recognized as the main reason of maternal morbidity and mortality. Uterine atony, birth trauma, retained tissue and coagulation defects are know etiopatogenic factors of early PPH. Physiological mechanisms that limit postpartum blood loss are: contractions of the myometrium and local spreading of decidual hemostatic factors which cause clotting. The pathogenesis of most cases of PPH is a disturbance in one or both mechanisms [1][2][3][4][5][6]. The most common cause of PPH in more than 50% of cases is uterine atony, lack of effective contraction of the uterus after the delivery. In old textbooks and some recent papers, the distinction between diffuse (corporeal, fundal, upper uterine segment) uterine atony and lower uterine segment atony (LUSA) has been underlined. With diffuse atony, blood loss can be much greater than observed because a dilated and accid uterus may contain a signi cant amount of blood. When uterine atony is localized in the region of the lower uterine segment, the fundal region may be well contracted while the lower uterine segment is dilated and atonic and is detected during vaginal examination. When LUSA is the reason for PPH, conservative therapy is usually not su cient, due to the fact that there are < 10% myo brils in the region of lower uterine segment. Therefore, surgical hemostatic compressive and / or ligation management is necessary [2,3,[5][6][7][9][10][11][12][13]. Till now, the incidence of LUSA remains unknown [(2,3,5,6]. Besides clinical signs of early PPH and effective contraction of fundal region, vaginal examination relieves dilated, ballooning and atonic lower uterine segment that is heavy bleeding [3,6].
Ultrasound examination relives empty uterine cavity, ballooned out lower uterine segment and coagulum within. According to the literature there are many suggested procedures such: manual evacuation of the coagula, curettage, different compressive methods of uterine or vaginal tamponade, uterine compression sutures and uterine artery ligation techniques as well as administration of uterotonics, anti brinolytics, tranexamic acid and peripartum hysterectomy as the last resort for the treatment of intractable severe PPH [3,6,[9][10][11][12][13][14]. The main aim of surgical methods is prevention of obstetric hemorrhagic shock complicated by disseminated intravascular coagulopathy, preservation of uterus and fertility by sustaining from hysterectomy. Peri and postpartum hysterectomy is being mainly performed due to the heavy bleeding mainly caused by uterine atony or invasive malplacentation. Cesarean section and vaginal birth after cesarean section are associated with nine-old increased risk of peripartum hysterectomy [1,2,3,4].
According to our clinical experience, it is of most importance to identify LUSA as a clinical entity as its management differs from the management of corporeal uterine atony. In this paper original results about identi cation, diagnostics and surgical management of LUSA are being presented and analyzed.

Material And Methods
We have conducted a retrospective, clinical study during a ten years period (2010-2019) in our institution that is tertiary perinatal university center. Research was approved by Ethical Committee of our Hospital.
Condition identi ed as LUSA PPH was diagnosed according to the clinical ndings, accompanied by severe uterine bleeding -early PPH > 500 mL that persisted after administration of oxytocin (Syntocinon 5-10 IU in 500 mL of saline intravenously), uterostiptics (methyergometrine 0,2 mg iv., carboprost tromethamine 1-4 amp) and anti brinolytic drug (tranexamic acid (TXA) 1-2 g iv) therapy. Clinical examination reveals well contracted fundus and upper uterine segment while lower uterine segment is being ballooned; heavy bleeding from the cervix is being identi ed and lacerations and ruptures in the lower genital tract are being excluded (Fig. 1.). Ultrasound reveals contracted fundus of the uterus and empty uterine cavity while within the dilated uterine segment coagula are identi ed (Fig. 2.). The primary treatment of hemorrhagic obstetric shock is control of the source of the bleeding as soon as possible and uid replacement (crystalloids, colloids and blood transfusion). All procedures were performed in prolonged existing peripartum epidural analgesia or without anesthesia, because anesthesia is not necessary to perform these procedures.
We have collected and investigated data of perinatal interest like: age of the patient, parity, gestational age, comorbidity, course of the labor and delivery (induction of labor, spontaneous labor, fetal malpresentation, operative vaginal delivery), date about newborn (peripartal fetal hypoxia, gender, birth weight/length, Apgar score). Furthermore, we investigated different techniques of transvaginal surgical management of LUSA PPH: evacuation techniques (removal of retained placental tissues or coagula Page 4/13 manually or instrumentally), ligation techniques (Losickaja, Hebitsch-Huch, Habek) and compressive techniques (Gauze, balloon thamponade). Blood loss was closely monitored in order to identify the grade of obstetric hemorrhagic shock (grade III/IV with the loss of 2000-2500 mL of blood volume) and need for uid replacement, (massive) blood transfusion and need for intensive care monitoring in the intensive care unit (ICU). We also evaluate the need for peripartum hysterectomy. We did not record any deaths associated with LUSA PPH. All analyzed results are presented in numbers and percentage in Table 1.

Results
This particular study, conducted on our center conducted during 10 years period of time (2010-2019) enrolled total number of 29 543 deliveries with 215 cases of early PPH (0,72%). LUSA was diagnosed in 44 cases or in 29,93% in all uterine atony cases. We did not record LUSA PPH after cesarean delivery, but exclusively in vaginal births (and VBAC).
Average age of parturient women was 32,18 years, parity 1,77 and gestational age 39,3 weeks. Gestational diabetes was diagnosed in 6 cases, and in 3 cases hypertension with or without anemia was identi ed. In 50% of the all LUSA cases labor was stimulated after the premature rupture of membranes. In 3 cases oligohydramnios and in 2 polyhydramnios and vaginal birth after cesarean section (VBAC) were diagnosed. Episiotomy was performed 7 times during delivery, instrumental delivery (vacuum extraction) was conducted 3 times and releasing impacted shoulders in 1 case by different maneuvers (shoulder dystocia). All newborns were in vertex presentation, 3 in dorsoposterior occipital presentation. Due to the fetal hypoxia 2 newborns were delivered instrumentally (vacuum extraction). Apgar score of all newborns was ≥ 9/10 in the 1st and 5th minute. Statistically there were more female newborns. The was only 9% of babies that were large for gestational age (> 4000g).
Exploration of the lower uterine segment accompanied by evacuation of the coagula was conducted in 5 cases (11,36%), haemostatic ligation procedures according to authors: Losickaja in 2 cases, Hebisch-Huch in 9 cases, Habek in 5 cases, Hebisch-Huch + Losickaja in 9 cases. Evacuation procedures were combined with ligation techniques in 7 cases, evacuation methods with ligation techniques and balloon tamponade in 2 cases, exploration combined with gauze tamponade in 1 case and ligation procedures with balloon tamponade in 3 cases. According to our results, haemostatic ligation procedures alone or combined with tamponade, have shown to be highly effective in 88,63%.
There was just 1 case of severe obstetric hemorrhagic shock complicated with disseminated coagulopathy of 2nd grade that required massive transfusion. Total number of 21 patients (47,72%) were treated with blood transfusion and fresh frozen plasma due to obstetric hemorrhagic shock, but only 6 of them were stationed in ICU for intensive care and monitoring. We have not performed any transabdominal procedures including hysterectomy. We have not recorded any early or late postoperative complications like stenosis, lacerations or bleeding, progression in 3nd grade of coagulopathy and multiorgan failure.

Discussion
In the recent literature there are only 9 papers that are identifying LUSA as a special clinical entity and as a type of early PPH that requires different diagnostic and therapeutic approach to resolving PPH. It is interesting that old obstetric manuals have pointed out the problem of LUSA as well as very logical transvaginal approach to resolving it (tamponade of uterus and vagina according to Dührssen and Mange) [2,5]. It should be mentioned that Losickaja has applied stitch of the posterior lip of the cervix in the year 1965. as a method for resolving uterine atony [7], while Hebisch-Huch have established successful method of mechanical ligation of cervical braches of the uterine artery that are simultaneously contracted through the cervicohypotalamic re ex [13]. Balak and Kafali have reported their experience about haemostatic cervical suturing that controls site of the hemorrhage on the cervical lips and on the lower uterine segment, and was proven to be effective even in the cases of LUSA [14,15].
Habek has recently presented his own compressive surgical technique of perpendicular inverted cervical sutures that was very effective in 9 cases of LUSA where it was used as a primary surgical method for preventing further development of PPH and obstetric hemorrhagic shock and eventually preserving fertility [9].
Introducing TXA into the algorithms of treating PPH has signi cantly lower maternal morbidity in the sense of the development of obstetric shock, coagulopathy and need for massive transfusions [16]. TXA was rst introduced in Croatia in the year 2009 and algorithm for prophylactic use of TXA and treatment for early PPH was presented in our Clinic. In our textbook (Obstetric operations, Habek and cooworks) that was published in the year 2009 we have described different transvaginal surgical procedures applied for patients with uterine atony especially with LUSA: haemostatic ligation procedures (Losickaja, Hebitsch-Huch), tamponade (Menge, balloon/gauze (impregnated in carboprost or TXA) tamponade, Bakri balloon, Sengestaken-Blakemore tube). We believe that traction of the uterus towards vagina has certain impact that resembles so called Pringel maneuver by obstruction of circulation and decreasing the amount of haemorrhage. All of the mentioned methods are relatively simple and applicable especially because they are being performed vaginally [3].
Known risk factors for LUSA are: prolonged and precipitated delivery, polyhydramnios, fetal malpresentation or malposition (de ection of the fetal head), multiparity, low-lying placenta, VBAC, assisted reproduction, hysteroscopy, rarely LUSA may be caused by cervical and myometrial lacerations [2,3,[5][6][7][9][10][11][12][13][14][15]. In our research there were no signi cant maternal or fetal risk factors for developing LUSA, except of labor induction and labor stimulation. Induction of labor was present in 27,27% of cases, and 22,73% of labor were stimulated due to preterm rupture of membranes, what accounts for 50% of known peripartal risk factors. According to our results, induction or stimulation of labor was identi ed as an isolated risk factor for developing LUSA.
We would like to emphasize, that we have obtained similar results in our research; blood transfusion was administrated in 47,72% of patients, while only 1 patient required massive transfusion, as already noted.
In more than 40% of cases we have successfully applied one or two combined ligation techniques (Hebitsch-Huch, Losickaja), followed by Habek modi ed compressive technique or compressive methods with balloon or gauze tamponade. We did not use curettage because we thought that we would damage the already damaged dilated surface of the cervix, we were guided by the philosophy of obstruction of circulation with ligatures and tamponade with therapy with uterotonics and tranexamic acid, to establish the missing mechanism of thrombo-and myotamponade.
Kafali and coworkers [15] have presented e cacy of applied haemostatic sutures in 3 cases of uncontrolled bleeding from the lower uterine segment.  [19]. Noninvasive procedure of bilateral cervix apex clamping (BCAC) rst described by Jiang [21] was shown to be effective in cases of refractory PPH. In the total number of 13 359 vaginal deliveries, BCAC was performed in 44 cases (0,33%) with e cacy of 93,2%. Recent studies have shown good hemostasis accomplishment in the treatment of LUSA with the use of Chitosan gauze [12,22]. Dueckelmann and coworkers [12] have presented results of their comparative study in the treatment of women with PPH with either uterine packing with chitosan covered gauze compared to balloon tamponade. The major reason for PPF was LUSA. In the group of patients treated with balloon tamponade postpartum hysterectomy was performed in 3 patients, while in the group of patients treated with uterine packing covered with Chitosan gauze there was no need for such a procedure. Therefore, authors according to their results, suggest the use of uterine packing covered with Chitosan gauze in the cases of LUSA, placenta previa bed bleeding and/or coagulopathy.
Transvaginal approach for surgical treatment of LUSA is accessible, feasible, successful and life saving. It can be easily performed in inpatient and outpatient care settings followed by administration of uterotonics, uterostiptics and TXA and uid replacement. All of the above mentioned methods are of great importance in the prevention and treatment of severe PPH, obstetric hemorrhagic shock, development of coagulopathy, multiorgan failure, postpartum hysterectomy and nally vital for fertility preservation.

Conclusion
Page 10/13 LUSA should de nitely be identi ed and understood as a clinical entity. With proper medicamentous therapy transvaginal surgical procedures should be applied. We suggest evacuation of coagula from balonated cervix followed by haemostatic ligation methods (Hebitsh-Huch, Losickaja, Habek) that reduce the bleeding from the cervical blood supply and from the wide cervical surface. Tamponade balloon/gauze should be applied if bleeding persists. Above mentioned methods have shown to be highly effective for fertility preservation.

Declarations
Funding: None Con icts of interest/Competing interests: The authors declare that they have no con ict of interest. Ultrasound pictures of lower uterine segmentatony