Postpartum Hemorrhage



Postpartum Hemorrhage


Divya Dethier

Julianna Schantz-Dunn



OVERVIEW

Postpartum hemorrhage (PPH) is a leading cause of maternal mortality affecting 1% to 5% of all deliveries, although the incidence varies widely. PPH is the leading cause of maternal mortality in low-income countries, causing one-quarter of all maternal deaths globally.1 In the United States, PPH accounts for greater than 10% of maternal mortality and is the primary contributor to maternal morbidity.2 The most common cause of PPH is uterine atony.3 PPH is a clinical diagnosis, and timely recognition and active management of the third stage of labor are key to the effective treatment of PPH and reduction of maternal morbidity and mortality.





ETIOLOGY

The major causes of PPH are represented by the mnemonic “Four T’s”: uterine atony (Tone), lacerations (Trauma), retained products or placental disorders (Tissue), and coagulation defects (Thrombin) (Table 27.1).3,7









TABLE 27.1 The “Four T’s” Mnemonic Device for Causes of Postpartum Hemorrhage

























T’s


Cause


Incidence (%)


Tone


Atonic uterus


70


Trauma


Lacerations, hematomas, inversion, rupture


20


Tissue


Retained tissue, invasive placenta


10


Thrombin


Coagulopathies


1


Data from Evensen A, Anderson JM, Fontaine P. Postpartum hemorrhage: prevention and treatment. AFP. 2017;95:442-449.



Tone

Uterine atony is the most common cause of PPH. Atony means the uterus is not effectively contracting after delivery and feels soft or “boggy.” The diagnosis is made by palpating the uterus and feeling a lack of firmness despite uterine massage and oxytocin (given in the third stage of labor when the placenta is being delivered). Risk factors for uterine atony include conditions that prevent the uterus from contracting down or lead to overdistention of the uterus (Table 27.2).

After delivery, palpate the uterine fundus to assess for firmness. If the fundus is firm, it does not necessarily mean that the entire uterus is firm. Often, the lower uterine segment can be boggy or poorly contracted, while the fundus feels firm. This may be caused by a blood clot that is preventing the lower part of the uterus from contracting down. A bimanual examination is helpful to assess lower uterine segment tone and the presence of retained clots.


Trauma

PPH may result from trauma to the uterus or the genital tract, either from lacerations or surgical incisions. Between 60% and 90% of women who deliver vaginally will have a perineal laceration.8,9 Cervical and vaginal lacerations can lead to excessive vaginal bleeding; therefore, a detailed visual inspection of the lower genital tract should be conducted if a source is not readily identified. Externally visible tears include perineal lacerations or labial lacerations.

Vaginal lacerations or sulcal lacerations (tears that run deeply into the posterior vagina) as well as cervical lacerations can often bleed heavily due to the large blood supply to the vagina and cervix in term gestations and require good visualization to identify with retraction of the vaginal walls.



Thrombin

Inherited or acquired coagulation defects are another potential etiology of PPH. Inherited bleeding disorders include thrombocytopenia and clotting factor deficiencies (such as von Willebrand’s, hemophilias). Therapeutic anticoagulation may also be a cause of hemorrhage. Acquired coagulation defects include preeclampsia; hemolysis, elevated liver function tests, and low platelet (HELLP) syndrome; acute fatty liver of pregnancy; sepsis; amniotic fluid embolism; placental abruption; and intrauterine fetal demise. These conditions may cause an imbalance in the hemostatic and fibrinolytic systems that lead to disseminated intravascular coagulation (DIC), which is a widespread activation of the clotting cascade with depletion of coagulation factors and platelets resulting in uncontrolled hemorrhage.10,11 In consumptive coagulopathies of pregnancy, fibrinogen is consumed more rapidly than other factors and is critical to anticipate as failure to replete coagulation factors prior to administration of other blood products or fluids can worsen the underlying coagulopathy.


CLINICAL FEATURES

The clinical evaluation of PPH is based on the physical examination and careful assessment of signs and symptoms suggestive of hypovolemia. Tachycardia will be the first sign of compensated shock, followed by decreasing blood pressure and must be considered in the context of the patient’s baseline vital signs.

Dec 30, 2020 | Posted by in EMERGENCY MEDICINE | Comments Off on Postpartum Hemorrhage
Premium Wordpress Themes by UFO Themes