Internal Iliac-Artery Balloon Occlusion in a Patient with Placenta Increta During Cesarean Hysterectomy

Introduction

Abnormal attachment of placenta to the myometrium may occur when there is a deficiency of decidua and when there is invasion of the myometrium by chorionic villi. Abnormal attachment of placenta (accreta, increta, or percreta) is an uncommon but potentially lethal cause of maternal mortality from massive postpartum hemorrhage (PPH). ¹

The risk factor for invasive placentation is presence of a uterine scar, usually following a cesarean delivery. ² The incidence has increased from 1:30,000, 50 years ago to 1:2500 to 1:550 in recent years.^3.PPH, adjacent organ injury, ileus, infection, and thromboembolic complications are all markedly increased in the presence of invasive placentation, ⁴ leading to increased rates of maternal morbidity and mortality. The current treatment of third trimester hemorrhage caused by abnormal placentation is cesarean hysterectomy, which may be complicated by a large volume of blood loss. ⁵ In this case, a technique that provided temporary prophylactic balloon occlusion of the internal iliac arteries to avoid massive hemorrhage during hysterectomy was used.

Case

A 27-year-old woman, gravida 2, para 1, was diagnosed with placenta previa (placenta percreta on an ultrasonography (USG) performed in a private center), at 35 weeks and 1 day of gestation. She had a history of prior cesarean delivery for placenta previa 1.5 years earlier. Her antenatal period was uneventful, except that she had an episode of bleeding per vaginum in the first trimester, which was managed conservatively.

On ultrasound, gestational parameters corresponded to the period of gestation, estimated fetal weight (EFW) 2614 g, and placenta was low lying and seen to cover the os and to invade the lower uterine myometrium with a streak of normal myometrium seen peripherally. It was also seen to compress the adjacent wall of urinary bladder, suggestive of placenta increta.

The patient was managed conservatively. Three days after admission she had spotting per vaginum and mild intensity uterine contractions started. Nonstress tests (NST) were done on the patient every day, and the fetal heart rate was monitored at regular intervals with a stethoscope as well as a fetal Doppler monitor.

A decision to perform urgent surgery was made, and informed consent was given by the patient for cesarean delivery and prophylactic balloon catheterization of the internal iliac arteries. The need for cesarean hysterectomy was also explained preoperatively, in case it was necessary, as the placenta was seen to invade the lower uterine myometrium suggestive of placenta increta on imaging. The patient and attendants were appropriately counseled regarding this procedure, as the patient was young and might have to undergo hysterectomy if needed. Preliminary preparation consisted of informing the anesthesia team prior to the operation, and ensuring that the interventionist, surgeon, neonatologist, and hematology departments were ready for surgery. The patient's hemoglobin was 11.1 gm%, her platelet count was 1 lac per 40,000, and her coagulation profile was normal. The plan was to perform the internal iliac artery, bilateral balloon occlusion preoperatively, and then proceed to cesarean delivery with the patient under general anesthesia, with the aid of surgeons, and finally to perform total hysterectomy. On the day of surgery, a preoperative fluoroscopy-guided balloon catheterization was performed. Through 6 Fr sheaths inserted in both groins, access to the internal iliac arteries by a contralateral approach was achieved through which two 0.025-″inch guide wires were kept in the descending aorta. Two 8×60 mm (Bard) occlusion balloons were placed at the origin of the internal iliac arteries bilaterally. Fluoroscopy time was recorded. The sheaths and catheters were connected to saline flush solutions, and the patient was transported to an operating room with fluoroscopic capability. Particular attention was paid to ensuring minimal fetal radiation exposure (fluoroscopy time 42 seconds). Immediately after balloon insertion, the patient was taken to an operating table, and the fetal heart rate checked with a stethoscope. General anesthesia was administered. A single live female newborn was delivered by cesarean section. The newborn did not cry at birth, but with resuscitation, appeared to be vigorous and healthy. The infant's APGAR score at 1 minute was 3, and, at 5 minutes, it was 8. Occlusion balloons were inflated at the time of cord clamping. The balloons were inflated until they assumed a slightly elliptical shape, indicating apposition against the wall of the hypogastric artery. A small test dose of contrast medium confirmed flow arrest. The balloons were intermittently deflated after every 2 minutes during the procedure, to determine adequate blood supply. Finally, a hysterectomy was performed. Balloons were deflated after the surgery, immediately before abdominal closure, after ensuring hemostasis within the pelvic cavity, but the sheath was kept in situ for 6 hours postoperatively, so as to facilitate uterine artery embolization if that became necessary. Arterial sheaths were removed in the recovery suite and the patient was subsequently transferred to the intensive care unit (ICU) for a minimum of 24 hours. Strict watch for PPH was kept during this time.

Intraoperatively, the lower uterine segment was very vascular, increased vascularity of the bladder wall was seen, and the placenta was invading the myometrium, but not up to the serosa. The bladder could be separated with difficulty. The placenta was invading the myometrium and could not be separated. Hence, total hysterectomy was performed. Total blood loss was ∼800 cc. One packed cell was transfused intraoperatively.

Results

The patient was shifted to the recovery room after surgery. She remained stable in the recovery room; bleeding per vaginum was within normal limits. Therefore, the femoral sheaths were removed 6 hours after surgery. Postoperatively, intravenous antibiotics were given. The urinary catheter was removed on day 7, and the patient remained healthy; she was discharged well after stitch removal on day 9. Her histopathology report showed focal penetration of the myometrium by chorionic villi suggestive of placenta increta. Her cervix, placenta, and umbilical cord showed no specific pathology.

Discussion

The incidence of abnormal placentation in patients with a placenta previa increases from 3% in those with no history of cesarean section to >60% in patients who have had more than two prior cesarean deliveries. ⁴

Multiparity, advanced maternal age, previous dilatation and curettage, hypertensive disorders, and tobacco use are also risk factors for placenta accreta in patients with a placenta previa. ⁶

Abnormal placentation (accreta, increta, percreta) has overtaken uterine atony as the leading indication for peripartum hysterectomy ⁷ and further massive hemorrhage, hypovolemic shock, or disseminated intravascular coagulation (DIC) and maternal morbidity and mortality. Therefore, antepartum recognition of invasive placentation is important for planning a multidisciplinary approach to a safe delivery and minimizing the risk of PPH. Preoperative color Doppler USG and magnetic resonance imaging (MRI) are used to establish the diagnosis of abnormal placentation and guide clinical management, which can lead to more favorable outcomes. ⁸

With a prenatal diagnosis of placenta accreta confirmed or suspected, the implementation of a multidisciplinary team approach is appropriate. ⁶ The following specialties become involved: radiology, anesthesiology, urology, interventional cardiology, neonatology, and transfusion medicine.

Prophylactic internal iliac artery occlusion should be introduced to reduce intraoperative blood loss in patients at high risk for peripartum hemorrhage.

Alvarez et al. found that this significantly decreased mean blood loss and transfusion requirements during hysterectomy. ⁹

Other studies have shown conflicting results concerning the efficacy of prophylactic internal iliac artery ballooning, some have reported satisfactory outcome for decreasing the mean blood loss and transfusion requirements, ⁸ and some have reported no benefit. ¹⁰ (Mean blood loss did not decrease because of rich collateral blood supply to the uterus). The authors of these studies proposed that subsequent embolization before deflation of balloons should be mandatory. Optimal placement site of the catheter for ballooning and balloon inflation time during the operation can be critical factors affecting outcome. An exposure to radiation >200 mGy can increase the risk for fetal congenital malformations in humans. ¹¹

Occlusion of the internal iliac arteries does not eliminate the blood flow to the uterus, because of the collateral vascular structures in the pelvis. The technique reduces the pulse pressure distal to the site of occlusion, thus reducing blood loss. ⁸

The overall efficacy and success rates of temporary internal iliac artery occlusion using endovascular balloons have not been established, because of the limited number of cases studied. Studies regarding future fertility and subsequent pregnancies have shown no adverse effects. ¹²

An ideal embolic agent should be inexpensive, readily available, easy to use, available in a wide variety of sizes for various applications, and radiopaque to prevent non-target embolization; cause mechanical occlusion without the need of superimposed thrombosis; and have a reproducible result whenever used, and a predictable and precise delivery. ¹³ No single agent exists; therefore, it is for the user to decide which agent is clinically applicable.

The temporary occlusive method is usually one of the following:

• Foam

Gelfoam is classified as a short-acting occluding agent. The advantages of gelfoam are its availability, low cost, and the ease and speed of delivery. However, delayed recanalization is one of its disadvantages. ¹⁴ Most cases require 20–30 days of recanalization after embolization. Another disadvantage of gelfoam is less selectivity, because it may reflux into non-target arteries. It is radiolucent and has an unpredictable delivery.

Microcoil is a superselective material. It allows precise deployment. Although rare, ischemic complication is still a major concern. ¹⁵

With balloon occlusion, ischemic complication, although rare, is still a major concern. ¹⁵ Balloon occlusion, like any other endovascular treatment, may cause endothelial damage and result in thrombus formation and subsequent embolus. Prolonged balloon occlusion can cause tissue ischemia. Therefore, intermittent deflation of the occluded balloon is sometimes needed to reduce the risk of tissue ischemia. Temporary arterial balloon occlusion is an effective and safe alternative for controlling hemorrhage. This technique should be considered in emergent situations and when surgical intervention is technically not feasible.

Polyvinyl alcohol (PVA) particles are permanent agents. They are tiny balls 50–1200 um in size. The particles are not meant to mechanically occlude a vessel. Instead, they cause an inflammatory reaction. Unfortunately, they have a tendency to clump together, as the balls are not perfectly round. The clump can separate a few days later, failing as an embolic agent.

Acrylic gelatin microspheres are superior permanent particulate embolic agents. They are similar to PVA, but are perfectly round, so they do not clump together. The balls are fragile, so they may crack inside small catheters.

Conclusions

This case illustrates that prophylactic temporary occlusion of the internal iliac arteries using balloons might be a safe and effective treatment option for patients at high risk for peripartum hemorrhage.

A short operating time with early removal of the endovascular catheters and close postoperative surveillance of the vascular system is required with this procedure, to minimize the risk of vascular complications.