A 24-year-old primigravid patient at 38 weeks gestation undergoes vaginal delivery of healthy twins after a prolonged labor course. Shortly after the placenta is delivered, profuse vaginal bleeding and a boggy uterus are noted on examination. Uterine massage and uterotonic medications fail to stop the bleeding. The patient is taken to the operating room for a laparotomy. Control of this patient's bleeding can best be achieved through bilateral ligation of which of the following arteries?

Question

A 24-year-old primigravid patient at 38 weeks gestation undergoes vaginal delivery of healthy twins after a prolonged labor course.  Shortly after the placenta is delivered, profuse vaginal bleeding and a boggy uterus are noted on examination.  Uterine massage and uterotonic medications fail to stop the bleeding.  The patient is taken to the operating room for a laparotomy.  Control of this patient's bleeding can best be achieved through bilateral ligation of which of the following arteries?

Quizplus · Accepted Answer

11ec160b_3577_af7a_9249_69962485c3d2_MD0001_00 Postpartum hemorrhage (PPH), an obstetric emergency, is a leading cause of maternal mortality. A common cause is uterine atony (failure of the uterus to contract and compress the placental site vessels), as evidenced by a boggy uterus. Surgery is indicated when medical management (eg, uterotonic medications) cannot control uterine bleeding. The main blood supply to the uterus is the uterine artery, a branch of the anterior division of the internal iliac artery. However, there are robust collaterals (eg, vaginal, ovarian) to the uterus during pregnancy such that in cases of severe PPH, ligation (tying off with suture) of the uterine arteries may fail to control the bleeding. In these cases, bilateral ligation of the internal iliac artery (also known as the hypogastric artery), the main blood supply to the pelvis, is performed to decrease flow rate and pulse pressure within all pelvic vessels, which can stop uterine bleeding and avoid hysterectomy. The structures supplied by the internal iliac arteries are typically unharmed by the procedure due to anastomoses with branches of the external iliac artery (eg, medial femoral circumflex-obturator anastomosis) or eventual recanalization. Therefore, in women of childbearing age, fertility is preserved and complication rates (eg, buttock claudication) are low. (Choices A and B) The aorta bifurcates into the common iliac arteries, which bifurcate into the internal and external iliac arteries. The external iliac becomes the femoral artery after exiting the pelvis and supplies the leg. Bilateral ligation of the common or external iliac would cut off blood flow to the lower extremities, leading to ischemia and necrosis of the legs. (Choice D) The internal pudendal artery, also a branch of the anterior division of the internal iliac, runs through the sciatic foramina to supply the perineum. Because the internal pudendal artery is distal to the uterine artery on the internal iliac, ligation would not decrease uterine blood flow. (Choice E) The ovarian artery, which originates from the abdominal aorta, supplies primarily the ovary and secondarily the uterus. Although bilateral ligation could somewhat decrease uterine blood flow, it would also cause irreversible ovarian necrosis, infertility, and menopause. Educational objective: The internal iliac artery (hypogastric artery) supplies blood to the pelvis, including the uterus via the uterine artery. Therefore, bilateral ligation of the internal iliac artery is a potential surgical management option for postpartum hemorrhage due to uterine atony. __________ References: Step-by-step ligation of the internal iliac artery. (http://www.ncbi.nlm.nih.gov/pubmed/30499283) Outcomes of hypogastric artery ligation and transcatheter uterine artery embolization in women with postpartum hemorrhage. (http://www.ncbi.nlm.nih.gov/pubmed/30638485)

A 24-Year-Old Primigravid Patient at 38 Weeks Gestation Undergoes Vaginal