Postpartum Hemorrhage

History

• Primary postpartum hemorrhage
  • Patient or caregiver may note steady, heavy bleeding. Saturation of 1 or more pads in 5 minutes is concerning; however, visual estimates of blood loss are inaccurate ^c1
  • Patients with severe hemorrhage may become light-headed, nauseated, clammy, or dyspneic ^c2c3c4c5
  • In some cases, bleeding into soft tissues results in an expanding hematoma and severe pain at the site ^c6
• Secondary postpartum hemorrhage
  • Patients may note gradual or abrupt escalation of vaginal bleeding ^c7
    • In cases caused by infection or retained products of conception, bloody discharge may be characterized by a foul odor and patients may experience low abdominal pain or cramping ^c8c9c10c11
  • Patients may have symptoms of anemia (eg, easy fatigability, light-headedness, dyspnea) ^c12c13c14

Physical examination

• Primary postpartum hemorrhage
  • Assess airway and vital signs ^r12
    • Moderate blood loss may occur without affecting vital signs; presence of tachycardia, tachypnea, or low blood pressure indicates loss of 1500 mL or more ^r11c15
    • Altered mental status may be evident, and may indicate inadequate perfusion ^c16
  • Blood loss may be quantified by a combination of the following: ^r4r13
    • Visual estimation by an experienced observer ^c17c18
      • Under- and overestimation are common based on visual estimation alone
    • Comparing weight of saturated gauze and linens with previously established dry weights ^c19
    • Direct measurement of blood in the suction canister and in the collection pouches of specially designed drapes ^c20
  • Conduct a thorough visual and manual examination of the perineum, vulva, vagina, cervix, and uterus to identify source(s) of bleeding ^r14c21c22
    • Inspect for lacerations, hematomas, retained placental cotyledons, or fetal membranes ^c23c24c25
    • Palpate for unexplained mass or tenderness ^c26
    • Assess uterine tone, which should be taut; bogginess suggests atony ^c27
  • Inspect placenta for missing cotyledons ^r14c28
• Secondary postpartum hemorrhage
  • If bleeding has been severe or continuous, there may be tachypnea and/or tachycardia ^c29c30c31
  • Pallor of conjunctivae, face, or palms may be evident ^c32c33
  • On pelvic examination, bleeding from the os may be observed; rarely, previously undetected tears or lacerations may be seen ^c34c35c36c37

Causes

• Primary postpartum hemorrhage (within 24 hours of delivery) ^r2c38
  • Uterine atony (most common, causing up to 80% of cases) ^c39
    • Inadequate involution of uterus after delivery; may or may not be associated with retained placenta or placental abnormalities ^c40c41
  • Trauma (second most frequent cause) ^c42
    • Includes spontaneous tears, incisions, and other instrumentation, as well as uterine rupture
  • Coagulopathy ^c43
    • Previously recognized conditions or medication
    • Rare hematologic conditions associated with pregnancy (eg, idiopathic thrombocytopenia, thrombotic thrombocytopenic purpura, HELLP syndrome) ^c44c45c46d1
    • Secondary coagulopathies resulting from the underlying obstetric event, increasing blood loss and complicating management
      • Amniotic fluid embolism results in acute overwhelming disseminated intravascular coagulation ^c47c48
      • Abruptio placentae and severe preeclampsia may also cause disseminated intravascular coagulation ^c49c50
      • Massive hemorrhage may trigger a consumptive coagulopathy; volume resuscitation may result in dilutional coagulopathy
  • Retained placenta ^c51
    • Placenta may tear, resulting in retained fragments
    • Placenta accreta (adherence to uterine wall) may prevent normal separation and expulsion
  • Uterine inversion ^c52
    • May occur spontaneously or may be iatrogenic, caused by incorrect use of fundal pressure and traction on the cord
• Secondary postpartum hemorrhage (24 hours to 12 weeks after delivery) ^r2r15
  • Retained products of conception ^c53
  • Subinvolution of the placental site
  • Infection (endometritis) ^c54
  • Inherited coagulation disorder ^c55
  • Gestational trophoblastic disease ^c56

Risk factors and/or associations

Primary diagnostic tools

• Primary postpartum hemorrhage
  • Quantify blood loss by visual estimation, by comparing weight of saturated gauze and linens with previously established dry weights, and/or by direct measurement of blood in measurement containers ^c79
  • Thoroughly examine the perineum, vulva, vagina, cervix, uterus, and placenta to locate main source(s) of bleeding ^r2c80c81
  • Occult blood loss may occur as perineal or pelvic hematoma; clinical clues include unexplained severe pain, tachycardia, and hypotension ^r4
  • Assess hemoglobin, hematocrit, and fibrinogen levels; platelet count; prothrombin time and INR; partial thromboplastin time; and fibrin degradation products at hemorrhage onset and periodically until stable ^{r5r6c82c83c84}
  • Obtain routine chemistries, particularly electrolyte and creatinine levels, at hemorrhage onset and periodically until stable ^r7c85
  • Obtain blood for type and crossmatch ^c86c87
  • Obtain imaging if source of bleeding is not obvious on examination, or if patient continues to deteriorate despite measures to control identified source(s) of blood loss ^r2
• Secondary postpartum hemorrhage
  • Obtain CBC and routine coagulation studies (eg, prothrombin time, INR, partial thromboplastin time) in all patients ^r18r19
  • Perform ultrasonography to evaluate for retained products of conception ^r20c88
  • Refer patients who present with hemorrhage onset 48 hours after delivery to a hematologist for screening for von Willebrand disease and other inherited or acquired coagulopathy ^r20

Laboratory

• CBC ^c89
  • Hemoglobin and hematocrit levels do not reflect blood loss immediately, but initial measure serves as a baseline for monitoring serial changes that may occur from further loss and dilution through fluid resuscitation
• Coagulation studies ^c90c91c92
  • Abnormalities in results may suggest previously undiagnosed condition (eg, clotting factor deficiency) or disseminated intravascular coagulopathy; the latter may be due to hemorrhage itself or another cause (eg, amniotic fluid embolism)
    • Disseminated intravascular coagulopathy is characterized by low or falling platelet count, prolonged prothrombin or partial thromboplastin time, elevated INR, low fibrinogen levels, and presence of fibrin degradation products ^r6
      • Fibrinogen levels are typically elevated in pregnancy; therefore, a level within general reference limits may be abnormally low in the context of pregnancy (ie, outside the pregnancy reference range) ^r5
        • Level below 200 mg/dL predicts severe postpartum hemorrhage
• Biochemistry panel ^c93
  • Disturbances of serum electrolytes and alterations in renal function are common in hemorrhages that require transfusion and fluid resuscitation; symptomatic hypocalcemia may complicate massive transfusion ^r12
• Consider β-hCG testing in late presentations of secondary postpartum hemorrhage; persistently high levels may suggest gestational trophoblastic disease ^r15c94

Imaging

• Ultrasonography ^r2c95
  • The American College of Radiology indicates that, for initial imaging, US duplex Doppler pelvis, US pelvis transabdominal, and US transvaginal are usually appropriate; the procedures are considered complementary ^r21
  • Indicated when source of bleeding is not evident on examination, particularly in secondary postpartum hemorrhage (which may be caused by retained product of conception)
  • May identify cause or location (eg, retained placenta, deep soft tissue hematoma)
  • May be done at the bedside

Other diagnostic tools

• Obstetric shock index has been proposed to aid in diagnosis and monitoring ^r22
  • Calculated as pulse rate divided by systolic blood pressure, measured at 10 minutes and 30 minutes after onset of postpartum bleeding
  • Value greater than 1 indicates significant blood loss
  • Presence of preeclampsia and high systolic blood pressure may result in a low value despite significant blood loss

Admission criteria

Admit all patients with primary postpartum hemorrhage if not already in hospital

• Patients in whom bleeding is not promptly controlled in delivery or postdelivery setting require transfer to operating room

Patients with secondary postpartum hemorrhage require admission if bleeding is extensive or if signs and symptoms of infection are present (eg, fever, abdominal tenderness)

Recommendations for specialist referral

• Refer to obstetrician-gynecologist to evaluate and manage source of bleeding
• Refer to hematologist, anesthesiologist, and/or critical care specialist to manage hemostatic resuscitation
• Refer stable patients who present with unexplained secondary postpartum hemorrhage to a hematologist for evaluation and management of possible coagulopathy

Drug therapy

• Uterotonic agents
  • None of the available agents has proven superior when oxytocin has been given prophylactically during the third stage of labor; for initial use as primary treatment of postpartum hemorrhage, oxytocin is superior to misoprostol ^r23
    • Oxytocin ^c96
      • Intramuscular
        • Oxytocin Solution for injection; Adults: 10 units IM as a single dose after delivery of the placenta.
      • Intravenous
        • Oxytocin Solution for injection; Adults: 10 to 40 units in 500 to 1,000 mL of dextrose or electrolyte solution continuous IV infusion; adjust infusion rate to sustain uterine contraction and control uterine atony.
    • Methylergonovine ^c97
      • Methylergonovine Maleate Solution for injection; Adults: 0.2 mg IM as a single dose, initially, after delivery of the anterior shoulder or placenta, or during the puerperium, initially; may repeat dose every 2 to 4 hours as needed, although unlikely additional doses will be of benefit if no response after first dose.
    • Carboprost ^c98
      • Intramuscular
        • Carboprost Tromethamine Solution for injection; Adults: 250 mcg IM every 15 to 90 minutes as needed, although unlikely additional doses will be of benefit if no response after 3 doses. Max: 2 mg.
      • Intramyometrial
        • Carboprost Tromethamine Solution for injection; Adults: 250 mcg by intramyometrial injection every 15 to 90 minutes as needed, although unlikely additional doses will be of benefit if no response after 3 doses. Max: 2 mg.
    • Misoprostol ^c99
      • Oral
        • Misoprostol Oral tablet; Adults: 600 mcg PO as a single dose.
      • Sublingual
        • Misoprostol Oral tablet; Adults: 800 mcg SL as a single dose.
• Hemostatic agents
  • Tranexamic acid ^c100
    • Tranexamic Acid Solution for injection; Adults: 1 g IV as a single dose, initially, within 3 hours of hemorrhage recognition; may give a second dose of 1 g IV if bleeding continues after 30 minutes or stops and restarts within 24 hours of the first dose.
  • Recombinant factor VIIa ^c101c102
    • Note: serious arterial and venous thrombotic events after administration of factor VIIa (recombinant) have been reported ^r31
    • For best effect, the following parameters should be met before administration: ^r32
      • Platelet count greater than 50,000/μL
      • Fibrinogen level of 50 to 100 mg/dL
      • Body temperature above 32 °C
      • pH greater than 7.2
      • Serum calcium level within reference limits
    • Coagulation Factor VIIA Recombinant Human Solution for injection; Adults: 35 to 90 mcg/kg IV as a single dose.
• Calcium gluconate ^c103
  • Calcium Gluconate Solution for injection; Adults: 300 mg (approximately 1.4 mEq elemental calcium) IV for each 100 mL of citrated blood infused.

Nondrug and supportive care

Fluid administration

• Crystalloids (eg, normal saline, Ringer lactate solution) are preferred and should be warmed if possible ^{r9c104c105c106}
  • Some authorities favor Ringer lactate solution over normal saline owing to possible chloride-induced renal vasoconstriction ^r30
• Administer enough to maintain circulation pending availability of blood, but avoid overhydration to prevent hemodilution and clot disruption; a systolic blood pressure goal of 80 to 100 mm Hg is appropriate ^r14

Transfusion of blood products ^r14

• Packed RBCs, fresh frozen plasma, and platelets are typically administered in a ratio of 1:1:1, although more complex regimens have been proposed ^{r2c107c108c109}
• Additionally, cryoprecipitate or fibrinogen is recommended if fibrinogen levels remain low after fresh frozen plasma infusion ^r2r5c110
  • Guidelines differ in levels at which fibrinogen replacement is indicated, ranging from 1 to 2 g/L (100 to 200 mg/dL) ^r5
  • Usual dose of 10 units of cryoprecipitate will raise fibrinogen levels by 100 mg/dL ^r30
  • Recommended dose of fibrinogen concentrate is 2 to 3 g ^r30
• Blood products should be warmed if possible ^r33
• Goal laboratory parameters include: ^r7
  • Hematocrit above 24%
  • INR less than 1.5 ^c111
  • Platelet count more than 50,000/μL ^c112
  • Fibrinogen more than 100,000 mg/dL ^c113

Comorbidities

• Preexisting coagulopathies increase risk of hemorrhage during delivery ^c120
  • Anticipatory infusion of coagulation factors may prevent excessive bleeding

At-risk populations

• All patients presenting for labor and delivery care ^c134

Screening tests

• Screening at admission has been proposed to assess risk and initiate blood banking procedures if appropriate ^r7c135
  • Low-risk criteria: singleton pregnancy, unscarred uterus, no previous postpartum hemorrhage, 4 or fewer previous vaginal deliveries, no known bleeding disorder
  • Medium-risk criteria: previous postpartum hemorrhage, previous cesarean delivery or other uterine surgery, 5 or more previous vaginal deliveries, multiple gestations, large fibroids, chorioamnionitis, indication for magnesium sulfate
    • Obtain blood for type and screen
  • High-risk criteria: placenta previa or accreta; hematocrit level less than 30% plus other risk, bleeding on admission, platelet count less than 100,000/μL, known coagulation defect
    • Obtain blood for type and crossmatch
  • Patients with 2 risk criteria in any category are moved to the next risk category