Case 6. Postpartum Hemorrhage

 A 29-year-old parous (G5P4) woman at 39 weeks’ gestation with preeclampsia delivers vaginally. Her prenatal course has been uncomplicated except for asymptomatic bacteriuria caused by Escherichia coli in the first trimester treated with oral cephalexin. She denies a family history of bleeding diathesis. After the placenta is delivered, there is appreciable vaginal bleeding estimated at 1000 cc.

» What is the most likely diagnosis?

» What is the next step in therapy?

ANSWERS TO CASE 6:

Postpartum Hemorrhage

Summary: A 29-year-old parous (G5P4) woman at 39 weeks’ gestation with preeclampsia delivers vaginally. She denies a family history of a bleeding diathesis. After the placenta is delivered, there is appreciable vaginal bleeding, estimated at 1000 cc.

Most likely diagnosis: Uterine atony.

Next step in therapy: Dilute intravenous (IV) oxytocin, bedside uterine massage and compression, and if this is ineffective, then intramuscular prostaglandin F 2-alpha (H emabate) or rectal misoprostol.

ANALYSIS

Objectives

1. Know the definition of postpartum hemorrhage.

2. Understand that the most common cause of postpartum hemorrhage is uterine atony.

3. Know the treatment for uterine atony and the contraindications for the various agents.

Considerations

This 29-year-old woman delivers at 39 weeks’ gestation and has an estimated blood loss of 1000 cc after the placenta delivers. This meets the definition of postpartum hemorrhage for a vaginal delivery, which is a loss of 500 mL or more. The most common etiology is uterine atony, in which the myometrium has not contracted to cut off the uterine spiral arteries that are supplying the placental bed. Bladder emptying, uterine massage, and dilute oxytocin are the first therapies. If these are ineffective, then prostaglandin F2-alpha or rectal misoprostol is the next agent to be used in this patient. Because she is hypertensive, methylergonovine maleate (Methergine) is contraindicated. It should be noted that if the uterus is palpated and found to be firm and yet bleeding continues, a laceration to the genital tract should be suspected. H er risk factors for uterine atony include preeclampsia sinceshe is likely to be treated with magnesium sulfate.

APPROACH TO:

Postpartum Hemorrhage

DEFINITIONS

POSTPARTUM HEMORRHAGE (PPH): Classically defined as greater than 500

mL of blood loss at a vaginal delivery and greater than 1000 mL during a cesarean

delivery. Practically speaking, it means significant bleeding that may result in hemodynamic instability if unabated.

Also, a decline in hematocrit levels of 10% has been used to define postpartum

hemorrhage, but it is not a satisfactory definition because determinations of hemoglobin or hematocrit concentrations may not reflect the current hematologic status.

UTERINE ATONY: Lack of myometrial contraction, clinically manifested by a

boggy uterus.

METHYLERGONOVINE MALEATE (METHERGINE): An ergot alkaloid

agent that induces myometrial contraction as a treatment of uterine atony, contraindicated in hypertension.

PROSTAGLANDIN F

2-ALPHA: A prostaglandin compound that stimulates myometrial contraction, contraindicated in asthmatic patients.

CLINICAL APPROACH

Postpartum hemorrhage is defined as primary (early) and secondary (late) according to whether it occurs within the first 24 hours or after that period. The most common cause of early PPH is uterine atony, with bleeding arising from the placental implantation site. (See Table 6– 1 for risk factors.) The physical examination reveals a boggy uterus. Table 6– 2 summarizes the stepwise approach to PPH . Because of the large proportion of cardiac output that perfuses the uterus and placental bed, a postpartum woman can exsanguinate in 10 to 15 minutes without intervention.

Uterotonic agents include intramuscular methylergonovine (Methergine), intramuscular prostaglandin F2-alpha, and rectal misoprostol. Ergot alkaloids should not be given in women with hypertensive disease because of the risk of stroke.

Prostaglandin F2-alpha should not be administered in those with asthma due to the potential for bronchoconstriction. Among these three agents, rectal misoprostol has emerged in many centers as the preferred agent due to high efficacy, low cost,

Table 6–1 • RISK FACTORS FOR UTERINE ATONY

Magnesium sulfate

Oxytocin use during labor

Rapid labor and/or delivery

Overdistention of the uterus (macrosomia, multifetal pregnancy, and hydramnios)

Intraamniotic infection (chorioamnionitis)

Prolonged labor

High parity

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Table 6–2 • TREATMENT FOR POSTPARTUM HEMORRHAGE

and low side effects. If medical therapy is ineffective, two large-bore intravenous lines should be placed, the blood bank should be notified, and anesthesiologist alerted. Intrauterine tamponade such as with a balloon can be performed while preparing for surgical therapy. Surgical therapy may include exploratory laparotomy with interruption of the blood vessels to the uterus such as uterine artery ligation or internal iliac artery ligation. More recently, suture methods that attempt to compress the uterus, such as the B-lynch stitch, have been described. If these fail, hysterectomy may be lifesaving.

Other causes of early PPH include genital tract lacerations, which should be suspected with a firm contracted uterus while bleeding persists. The vaginal side walls an cervix should be especially carefully inspected. Repair of the complete extent of the laceration is important. Uterine inversion (see Case 3), whether partial or complete, must also be considered. Placental causes include accreta or retained placenta. If the uterus is firm and there are no lacerations, one must also consider coagulopathy.

Secondary (late) PPH, defined as occurring after the first 24 hours, may be caused by subinvolution of the placental site, usually occurring at 10 to 14 days after delivery. In this disorder, the eschar over the placental bed usually falls off and the lack of myometrial contraction at the site leads to bleeding. Classically, the patient will not have bleeding until about 2 weeks after delivery and is not significantly anemic. Oral ergot alkaloid and careful follow-up is the standard treatment; other options include intravenous dilute oxytocin or intramuscular prostaglandin

F 2-alpha compounds.

Other causes of secondary postpartum hemorrhage include uterine atony (perhaps secondary to retained products of conception) and infection. Ultrasound examination helps to confirm the diagnosis. If uterus is atonic, uterotonic agents are the first-line therapy. If suspecting retained products of conception, suction dilation and curettage can be performed. Women with retained products of conception (POCs) generally have uterine cramping and bleeding. If suspecting infection (endometritis), broad-spectrum antibiotics are indicated. Endometritis is suspected with uterine fundal tenderness, fever, and foul-smelling lochia.

Emerging Concepts

Recent studies have indicated that active management of the third stage of labor reduces the incidence and severity of PPH . This includes oxytocin given immediately upon delivery of the infant, late cord clamping, and gentle cord traction with uterine countertraction with a well-contracted uterus. Several randomized trials found a 25% to 50% decrease in the incidence of PPH . Although retained placenta is a theoretical risk with early oxytocin administration, studies have not found this complication.

CASE CORRELATION

See also Case 3, Uterine Inversion, which is strongly associated with postpartum hemorrhage; see also Section I—Approach to Reading and What Is the Most Likely Diagnosis—for the clinical approach.

COMPREHENSION QUESTIONS

6.1 A 24-year-old G1P0 woman at 39 weeks’ gestation had induction of labor due to gestational hypertension. She was placed on magnesium sulfate for seizure prophylaxis. She was placed on oxytocin for 15 hours and reached a cervical dilation of 6 cm. After being at 6-cm dilation for 3 hours despite adequate uterine contractions as judged by 240 Montevideo units, she underwent a cesarean delivery. The baby was delivered without difficulty through a low-transverse incision. Upon delivery of the placenta, profuse bleeding was noted from the uterus, reaching 1500 mL. Which of the following is the most likely cause of hemorrhage in this patient?

A. Uterine atony

B. Uterine laceration

C. Coagulopathy

D. Uterine inversion

E. Retained placenta

6.2 A 26-year-old G2P1001 woman underwent a normal vaginal delivery. A viable 7 lb 4 oz male infant was delivered. The placenta delivered spontaneously. The obstetrician noted significant blood loss from the vagina, totaling approximately 700 mL. The uterine fundus appeared to be well contracted. Which of the following is the most common etiology for the bleeding in this patient?

A. Retained placenta

B. Genital tract laceration

C. Uterine atony

D. Coagulopathy

E. Endometrial ulceration

6.3 A 32-year-old woman has severe postpartum hemorrhage that does not respond to medical therapy. The obstetrician states that surgical management is the best therapy. The patient desires future childbearing. Which of the following is most appropriate to achieve the therapeutic goals?

A. Utero-ovarian ligament ligation

B. H ypogastric artery ligation

C. Supracervical hysterectomy

D. Ligation of the external iliac artery

E. Cervical cerclage

6.4 A 34-year-old woman is noted to have significant uterine bleeding after a vaginal delivery complicated by placenta abruption. She is noted to be bleeding from multiple venipuncture sites. Which of the following is the best therapy?

A. Immediate hysterectomy

B. Packing of the uterus

C. H ypogastric artery ligation

D. Ligation of utero-ovarian ligaments

E. Correction of coagulopathy

6.5 A 26-year-old G2P2 woman underwent a normal vaginal delivery 10 days previously. She comes into the doctor’s clinic complaining of a large amount of bright red bleeding beginning since 5 PM the previous day. Which of the following is the most likely diagnosis?

A. Uterine atony

B. Cervical laceration

C. Vaginal laceration

D. Subinvolution of the uterus

E. Normal menses

ANSWERS

6.1 A. Uterine atony is the most common cause of PPH , even after cesarean delivery. With a prolonged labor, such as with arrest of active phase, a patient is at risk for uterine atony. The finding of a boggy uterus would be confirmatory. Certainly, lacerations or injury to uterine vessels are potential issues and should be visible on examination. The treatment for uterine atony during cesarean is similar to a patient who underwent vaginal delivery, including intravenous dilute Pitocin, prostaglandin compounds (such as intramuscular

PG F 2-alpha or rectal misoprostol). If these measures are unsuccessful, surgical management of uterine atony includes ligation of blood supply to the uterus to decrease the pulse pressure (suture ligation of the ascending branch of the uterine artery or the utero-ovarian ligament or internal iliac artery) or placement of compression stitches (B-lynch stitch) that try to compress the uterus with external suture “netting.” Sometimes hysterectomy needs to be performed when the patient is unresponsive to these conservative surgical techniques.

6.2 B. Genital tract laceration is the most common cause of PPH in a well-contracted uterus. This is most likely arising from a cervical laceration, commonly laterally into or adjacent to the arterial supply of the cervix. Upon recognition of PPH , the physician should address the ABCs, assess the patient’s blood pressure (BP) and heart rate (H R), and have IV isotonic crystalloid infusing quickly. A second large-bore IV infusion should be started. The most common cause of PPH is uterine atony and so attention should be directed toward fundal massage and infusion of oxytocin (Pitocin). If the fundus is firm and the uterus well contracted, the next step should be to assess for a genital tract laceration. Inspection for whether the bleeding is coming supracervical (uterus) versus cervical or lower in the genital tract is critical. Supracervical bleeding speaks for coagulopathy, retained POC, or atypical uterine atony. The cervix and then vagina should be carefully inspected for lacerations. Often, if the patient is in a regular labor and delivery room, moving the patient to the operating room with adequate lighting and anesthesia can be helpful. Blood products should be on hand if bleeding persists. At times, a genital tract laceration may extend high into the vaginal fornix; careful assessment of the full extent of the laceration and judicious surgical repair is warranted.

6.3 B. Ligation of the ascending branch of the uterine arteries and the internal iliac (hypogastric) artery are methods for decreasing the pulse pressure to the uterus and can help in PPH . Ligation of utero-ovarian ligaments can be performed in addition to ligation of uterine arteries, which can diminish further blood flow to the uterus. Ligation of the external iliac artery would lead to lower extremity necrosis. A cervical cerclage is not a treatment option for hemorrhage; instead, it is a procedure performed in order to prevent preterm labor and delivery in a pregnant woman with cervical insufficiency.

6.4 E. Bleeding from multiple venipuncture sites together with abruption suggests a coagulopathy. This is a systemic response, so no type of localized treatment (such as hypogastric artery ligation or utero-ovarian ligament ligation) will fix the problem. A patient with disseminated intravascular coagulation can present with a simultaneously occurring thrombotic and bleeding problems, which makes it difficult to choose a treatment option.

6.5 D. The most common cause of late postpartum hemorrhage is subinvolution of the uterus, in which the placental implantation site does not decrease in size as expected; thus, when the eschar overlying the placental site falls off (7– 10 days after delivery), there is more bleeding than expected. The treatment is uterotonic agents such as ergot alkaloids or misoprostol. The bleeding almost always decreases quickly, such as within 12 hours.

CLINICAL PEARLS

» The most common cause of postpartum hemorrhage is uterine atony.

» The most common cause of early PPH with a firm, well-contracted uterus is a genital tract laceration.

» The most common cause of late postpartum hemorrhage (after the first 24 hours) is subinvolution of the uterus.

» Hypertensive disease is a contraindication for ergot alkaloids, and asthma is a contraindication for prostaglandin F2-alpha.

» The evaluation and treatment of PPH should be systematic and efficient and involves two aspects: stabilization of the circulatory status and addressing the hemorrhage.

» Stabilization of the patient begins by addressing the ABCs, ensuring asecond large-bore IV infusion of isotonic crystalloid and availability of blood products if needed, and constantly monitoring key hemodynamic parameters (mental status, BP, HR, urinary output, bleeding, and capillary refill).

» The systematic search for the etiology of PPH should begin with uterine atony, then genital tract lacerations with careful inspection to discern whether the bleeding is supracervical, cervical, or lower genital tract.

REFERENCES

American College of Obstetricians and Gynecologists. Postpartum hemorrhage. ACOG Practice Bulletin

76. Washington, DC; 2006. (Reaffirmed 2013.)

Cunningham FG, Leveno KJ, Bloom SL, H auth JC, Gilstrap LC III, Wenstrom KD. Obstetrical hemorrhage. In: Williams Obstetrics. 24th ed. New York, N Y: McGraw-H ill; 2014:619-670.

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Kim M, H yashi RH , Gambone JC. Obstetrical hemorrhage and puerperal sepsis. In: H acker NF, Gambone JC, H obel CJ, eds. Essentials of Obstetrics and Gynecology. 5th ed. Philadelphia, PA: Saunders;

2009:128-138.

WH O Recommendations for the Prevention and Treatment of Postpartum H aemorrhage. Geneva:

World H ealth Organization; 2012.

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