Wing and associates46 conducted a prospective, randomized, controlled trial that reinforces the need for judicious use of outpatient management. In their study, fewer than half the patients diagnosed with placenta previa prior to 37 weeks were candidates. The authors point out the small number of patients in their study, and the fact that vaginal bleeding recurred in approximately 60% of patients. Because of the difficulty of predicting which patients will have recurrent bleeding and when, outpatient management should be reserved for those judged to be compliant with home bed rest who can rapidly return to the hospital, if necessary.
Women with recurrent vaginal bleeding during outpatient management should be rehospitalized.
Intrapartum hemorrhage: Surgical techniques to stanch the flow
In the event of massive hemorrhage, immediate compression of the aorta below the level of the renal arteries will reduce the bleeding enough to allow time to evaluate the situation.56 At the same time, aggressive IV fluid resuscitation and blood transfusion should begin. Reevaluate coagulation status after every 5 to 10 U of blood.57
Focused repair may be effective. In some situations, the hemorrhage may be controlled by oversewing and repairing the focal placental site defects.40
Bracketing the bleeding area. Another measure is a circular suture technique in which interrupted sutures are placed on the serosal surface of the anterior and posterior aspects of the uterus and as deeply as possible into the endometrium in a circumferential manner, bracketing the bleeding area.58
The argon beam coagulator can be used to achieve hemostasis; it is more effective than traditional bipolar cautery at ensuring hemostasis in extensive areas.56,57
Stepwise devascularization was effective in 100% of 103 women with postpartum hemorrhage who did not respond to traditional management.59 It involves 5 procedures to be performed in sequence until hemostasis is achieved: unilateral uterine vessel ligation, bilateral uterine vessel ligation, low uterine vessel ligation, unilateral ovarian vessel ligation, and bilateral ovarian vessel ligation.
Hypogastric artery ligation is another option, but it is technically challenging and successful in less than 50% of cases.57 In fact, the time spent on this technique may actually lead to increased blood loss.
Components of safe delivery
A detailed plan is necessary when major hemorrhage is anticipated at the time of elective cesarean delivery for placenta previa, including consultation with experts in different disciplines such as radiology, anesthesiology, urology, pathology, blood bank, neonatology, and gynecologic oncology.
Also pay attention to the maternal red blood cell reserve. Iron and folic acid should be administered to prevent and treat anemia, and antepartum erythropoietin should be considered as a way of increasing the hemoglobin level in women with placenta previa. Autologous blood transfusion, including acute normovolemic hemodilution, is another option.
Pelvic vessel embolization
Elective embolization or occlusion of the hypogastric or uterine arteries has proved to be safe and effective for postpartum hemorrhage, with a success rate of more than 90% in women with normal coagulation.47
In addition, elective catheterization with a balloon-tipped catheter can be used prophylactically to reduce blood flow to the placenta. Prophylactic catheterization of the anterior division of the internal iliac arteries can be performed right before the scheduled cesarean section. An axillary approach is technically easier for fluoroscopically guided catheterization of the internal iliac.48 The actual fluoroscopy time is minutes, so the risk of fetal exposure to radiation and irreversible ovarian damage is minimal.
The fetus is monitored during the procedure, and the balloons are left in the deflated state until after delivery, reducing the risk of uteroplacental insufficiency. Balloon inflation after delivery occludes the hypogastric arteries and diminishes uterine arterial blood flow during surgery. In some cases, the temporary occlusive effect of the balloons may control intraoperative bleeding completely. If substantial bleeding persists, subsequent embolization of the uterine arteries is advised, using absorbable Gelfoam particles, which are temporary and do not damage pelvic organs. Menstruation is not impaired, and normal pregnancies have been reported after this procedure.49,50
In women who undergo cesarean delivery under regional anesthesia, placement of a dry epidural catheter for later dosing of anesthetic agents should be considered prior to balloon catheterization, since the patient’s mobility is restricted after placement of the balloon-tipped catheter.
This therapy is especially useful when there is a high index of suspicion for placenta accreta.
Recommendations at the time of delivery
Hysterectomy for placenta previa, placenta accreta
This procedure is technically challenging when there is a markedly enlarged uterus with engorged collateral vessels. One useful method, delayed ligation technique, was originally described by Dyer et al on the Tulane obstetrics service at Charity Hospital of New Orleans.53 This technique facilitates quick control of all uterine vasculature with rapid hemostasis. Later modification of this method involves successive clamping and severing of all vascular pedicles supplying the uterus, prior to their suture ligation, for quick control of bleeding.