The Low Down on Placenta Abruptio


Author: Colleen M Hayes, MBA, RN, EMT-P

Introduction

Normally the placenta does not separate from the uterine wall until the baby is born. When the placenta prematurely separates from the uterine wall severe hemorrhage can occur and threatens the life of both the baby and mother. Placenta abruptio is the leading reason for hemorrhage related deaths in pregnant women. Other causes of maternal death include cardiac disease, infection, pulmonary embolism, and pregnancy-induced hypertension complications. Most cases of abnormal bleeding during the second and third trimesters of pregnancy are caused by premature separation of the placenta from the uterine wall and abnormal placental implantation.

This article, Part 2 in 3-Part series: "The Low Down on Placenta Abruptio" will first review the tragic outcome of a case of placenta abruptio that ended in a lawsuit against EMS. Then this article will discuss the pathophysiology, incidence, causes, risk factors and emergency treatment for bleeding caused by placenta abruptio. The next edition of EMSvillage.com will present Part 3 of this series and will discuss pregnancy induced hypertension, eclampsia and other OB complications.

A True Story and A Real Lawsuit Case Against EMS

The headlines in newspapers after the lawsuit's verdict case read: "Paramedics Fail to Diagnose Symptoms of Abruptio Placenta and Hypovolemic Shock - Failure to Transport Mother to Hospital in Timely Manner - Emotional Distress Damages for Death of Infant, Born Alive, Who Died Next Day - $4.5 Million New York Verdict". The following information below is excerpted from the case summary:

The plaintiff, a forty-two year old self-employed consultant in her 36th week of pregnancy, claimed that at 3 a.m. on November 20, 1989, her membranes broke and she developed stabbing abdominal pains. Her treating obstetrician advised her to call 911. The evidence indicated that the ambulance arrived in a timely manner and that the two paramedics started an IV line, conducted a head to toe examination, and placed her on an EKG monitor before bringing her to the ambulance.

The plaintiff claimed that the defendant paramedics failed to promptly recognize signs of abruptio placenta and signs of hypovolemic shock, and negligently failed to immediately rush her to the hospital. Specifically, the plaintiff contended that her systolic blood pressure was ninety-six, which, she claimed, was indicative of internal bleeding, when taken together with the severe stabbing abdominal pains, and was indicative of abruptio placenta, a clear emergency situation for which she should have been rushed to the hospital. The plaintiff also contended that as a result, she arrived at least eighteen minutes later than would be acceptable under the circumstances.

The plaintiff claimed that this delay caused hypoxia to the fetus, which was delivered by cesarean section, and led to the death of the baby the following day. The plaintiff further contended that the published paramedic protocols for making a presumptive diagnosis of hypovolemic shock would be systolic pressure under 100 and diaphoresis, or excessive perspiration. The plaintiff contended that diaphoresis was present and that in view of this finding, taken together with the low blood pressure, she should have been treated in accordance with the protocol, which stated that the patient should be brought to the hospital immediately.

The plaintiff claimed that the IV line could have been inserted and the examination conducted in the ambulance while en route to the hospital. She contended that immediately upon arriving at the hospital, the nurses realized that she was suffering an abruptio placenta and a cesarean section was completed in a timely fashion at 4:40 a.m. The plaintiff contended, however, that the baby was born hypoxic with Apgar scores of two and four. Testimony indicated that the placenta was completely detached from the uterus at the time of birth. The plaintiff contended that if the baby had been brought to the hospital eighteen minutes earlier, the cesarean section could have been completed at a time when the fetal pulse was only slightly depressed and the placenta still attached. The plaintiff's expert testified that when the child became hypoxic, the fetus experienced pain and suffering from suffocation that would last several minutes in utero. The plaintiff also claimed that the procedures used during the one day of life, including intubation and the insertion of IV lines, were painful.

The plaintiff claimed that she suffered excessive bleeding, requiring a second surgery to control the bleeding after the baby was born, and that the massive blood loss resulted in kidney failure for a brief period. The plaintiff underwent multiple blood transfusions which rectified the difficulties and plaintiff suffered no permanent injury to the kidneys. She contended that the excessive bleeding, the need for a second surgery, and the kidney failure were additional injuries that were independent of the complications that would have stemmed from the abruptio placenta if it had been recognized and treated promptly. The plaintiff claimed that the onset of such an independent injury constituted an exception to the general rule precluding an award for damages for emotional distress stemming from the baby's death, and she brought this action for emotional distress stemming from the death of the child.

The plaintiff, who had a history of chronic depression and several incidents of severe depressive episodes, contended that the happiest time in her life was during the first three to four years following the birth of her son eight years before this incident. The plaintiff testified that she became pregnant again one year before the subject incident, but miscarried shortly thereafter, and that she had greatly desired another child. The plaintiff stated that she was very happy when she became pregnant with this child, and contended that the loss occasioned a severe depression. The plaintiff contended that although she has experienced significant improvement through therapy and the use of Prozac, she will require the medication for the rest of her life, and will suffer some residual depression. The defendant contended that the patient's signs and symptoms did not fall clearly into any mandated paramedic protocol and that the paramedics acted appropriately in using their clinical judgment. The defendant also contended that plaintiff required an examination, which included the taking of her vital signs, pursuant to and mandated by protocols. The defendant also contended that plaintiff's depression predated the incident, and partially stemmed from the earlier miscarriage, citing her psychiatrist's records describing a major depression prior to these incidents. The defendant argued that any depression stemming from this episode fully resolved. The defendant further claimed that any continuing difficulties and the need for Prozac stemmed from her prior depression. According to The New York Jury Verdict Reporter, the jury awarded plaintiff $4,500,000.

Incidence, causes and risk factors:

Placenta abruptio usually occurs in the third trimester of pregnancy, but it may occur any time after the 20th week. Placenta abruptio occurs in just a little less than 1% of pregnancies. However, the severe form (resulting in fetal death) occurs only in about 1 out of 500 to 750 deliveries. About 15% of all fetal deaths are caused by severe placenta abruptio.

While the cause of abruptio placenta is generally not known, there are risk factors associated with it. The known risk factors are as follows:

  1. Hypertension or high blood pressure during pregnancy is the most common risk factor and is associated with 2.5 to 17.9% incidence. However, approximately 50% of placenta abruptio cases severe enough to cause fetal death are associated with hypertension.
  2. Trauma to the abdomen, such as in the case of domestic violence (1.5% - 9.4% of all cases)
  3. Smoking
  4. Cocaine use
  5. Use of alcohol (more than 14 drinks per week)
  6. Mother over 40 years of age
  7. Previous abruptio placenta (after 1 prior episode there is a 4% recurrence, after 2 prior episodes the incidence of recurrence exceeds 20%)
  8. Premature rupture of the amniotic sac
  9. Diabetes mellitus in the pregnant woman
  10. Increased uterine distention (as may occur with multiple pregnancies or abnormally large volume of amniotic fluid)

Pathophysiology and Types of Placenta Abruptio

Recall that the placenta and umbilical cord connect the mother and the developing fetus. The placenta and umbilical cord provides oxygen and nutrients to the baby and eliminates carbon dioxide and waste products through a filtering system. A normal placenta is implanted high in the uterus and its surface attaches to the uterus completely. (Fig.1)

Fig. 1: The placenta normally implants high in the uterus.

 

Placenta abruptio happens when the placenta prematurely peels away from the normally implanted uterus with associated bleeding occurring between the separated placenta and the uterine wall. The amount of separation from the uterus in placenta abruptio ranges from partial to complete. (To view two photographs of placenta abruptio click here and here.)

Either the blood may accumulate in the uterus, causing a concealed hemorrhage (Fig. 2) because it is trapped between the placenta and uterine wall, or there may be an external hemorrhage (Fig 3.) when blood drains through the cervix and out the body. In placenta abruptio, blood vessels rupture and create a hematoma. This hematoma shears off the adjacent blood vessels, creating further bleeding and separation of the placenta.

Fig. 2: Concealed hemorrhage (gray color)
Fig.3: External hemorrhage (gray color)


Classification of placental abruption is based on extent of separation (i.e., partial vs complete) and location of separation (i.e., marginal Vs central). A classification system and corresponding clinical characteristics include the following:

Class 1 is the mildest type and represents approximately 48% of all cases.

No vaginal bleeding to mild vaginal bleeding
Slightly tender uterus
Normal maternal BP and heart rate
No coagulopathy (clotting problems)
No fetal distress

Class 2 is moderate and represents approximately 27% of all cases.

No vaginal bleeding to moderate vaginal bleeding
Moderate-to-severe uterine tenderness with possible tetanic contractions
Maternal tachycardia with orthostatic changes in BP and heart rate
Fetal distress
Low fibrinogen levels present (causing clotting problems)

Class 3 is severe and represents approximately 24% of all cases.

No vaginal bleeding to heavy vaginal bleeding
Very painful tetanic uterus
Maternal shock
Coagulopathy (Life threatening clotting problems)
Fetal death

Signs and Symptoms: Making the Diagnosis of Placenta Abruptio

While in the hospital ultrasound is used to locate the placenta's location and will help rule out placenta previa, the study is not reliable to diagnose, or rule out the diagnosis of placenta abruptio. The diagnosis of placenta abruptio is made primarily on clinical presentation. Symptoms may vary, depending on how much of the placenta has separated and when in the pregnancy it occurs. 30% of placenta abruptios are small and produce no symptoms. The main symptom of abruptio placenta is bright red or dark red bleeding from the vagina. The bleeding does not always occur, though, because the blood can be trapped behind the placenta or the baby. Other symptoms include abdominal pain, tenderness around the belly, lower back pain, rigidity of the uterus, uterine contractions, and decreased fetal movement.

The frequency of the most common symptoms are:

  1. Vaginal bleeding - 80%
  2. Abdominal or back pain and uterine tenderness - 70%
  3. Fetal distress - 60%
  4. Abnormal uterine contractions (e.g., hypertonic, high frequency) - 35%
  5. Idiopathic premature labor - 25%
  6. Fetal death - 15%

Vaginal bleeding that varies in amount (scant to heavy) or color (bright to dark red), depending on the location and amount of separation. Light bleeding does not necessarily mean a minor problem, because major bleeding may be occurring internally. Vaginal bleeding usually does not occur if the separation is slight. Vaginal bleeding may not occur in a small number of large separations if blood is trapped between the placenta and the wall of the uterus.

Considerations Related to Assessment

The classic presentation of placenta abruptio is painful cramps or contractions with dark red or bright red vaginal bleeding after the 20th week of pregnancy. The bleeding may be heavy or scant depending on the degree of separation and whether the hemorrhage is concealed or external. There is usually severe pain, uterine tenderness, and contractions or cramps. Remember the physiological changes in the pregnant woman that alters the way the EMS provider interprets certain vital sign changes. Click here to review the physiologic changes related to pregnancy from Part 1 "The 'Low Down' on Placenta Previa" of this series.

Your assessment may reveal signs of compensated or decompensated shock. Remember that some of the classic changes in the pregnant female effect cardiovascular, respiratory and fluid-volume status. These normal changes may conceal the earliest signs of hypovolemia. For example, due to the increased fluid volume during the normal pregnant state the mother can lose up to 35% of her blood volume before signs of shock are evident! The uterus can also contain up to 2 liters of blood. Just because external blood loss is absent or minimal, there may be significant occult hemorrhage. In meantime, the brain has told the sympathetic nervous system to vasoconstrict vessels supplying the fetus as a method to compensate for blood loss to the mother. While the mother appears stable the fetus is in serious jeopardy!

Resuscitative measures are indicated even if the mother appears stable and is normotensive because the fetus is most likely being be hypoperfused and in serious life threatening shock. Therefore, maintaining a high index of suspicion even in the absence of the "classic" signs of shock is warranted. Massive bleeding will threaten both the lives of the mother and the baby. If bleeding is massive, blood transfusion, and probably preterm delivery may be needed.

Prehospital Management of Placenta Abruptio

The first step in appropriate treatment is recognition of the emergency. Even if the mother is stable, the assumption must be made that a life threatening problem exists. After assessing your patient, provide any airway, ventilatory and circulatory support as needed. Immediate administration of high-flow oxygen and positioning the patient onto her left side for optimal perfusion is indicated. Pregnant women are susceptible to vena cava syndrome (compression of the abdominal aorta and vena cava) and should be placed in the left lateral recumbent position. Vena cava syndrome can be prevented and simply positioning the patient on her left side will optimize blood flow to both the fetus and mother.

Placenta abruptio is a surgical emergency when the patient and/or the fetus is in distress. It is impossible for the paramedic to make the actual diagnosis or gauge the degree of maternal risk or fetal distress in the field setting. Therefore your plan of care for the patient must include beginning transport immediately and enroute start a large bore IV and begin fluid resuscitation with an isotonic crystalloid IV fluid such as Normal Saline. Remember that even in the normotensive pregnant patient the fetus is still at risk and physiological body changes can mask the classic signs of shock we expect to see in the non-pregnant patient. Limit scene time to 10 minutes or less as you would with a trauma patient who would require emergent surgery for survival. Follow your local protocols carefully.

Notify the ED of the patient's parity, gravidity, history of any past cesarean section, maternal lifestyle (ETOH, smoking, etc.), LMP, due date, uterine size by fundal height, past medical history, medications taken, present condition and treatment being administered. This will allow the ED to alert the Labor & Delivery team so they may be prepared to serve this patient's special needs.

In-Hospital Management of Placenta Abruptio

The diagnosis for abuptio placenta is made by ruling out any other possible causes of the symptoms. Sometimes an ultrasound is used to help find the abruption, but it does not detect an abruption every time. If the baby is not in danger the mother will be hospitalized to allow the fetus to mature before delivery. A fetal monitor will be used to observe the baby's heart rate. If the bleeding is severe or there is apparent danger to the baby, a Cesarean Section will be performed immediately.

Prognosis

Maternal death rates, in various parts of the world range from 0.5 to 5% . Early diagnosis of the condition and adequate intervention should decrease the maternal death rate to 0.5 to 1%. Fetal death rates range from 50% to 80%. 15% of all causes of fetal deaths are caused by placenta abruptio. Upon hospital admission, no fetal heart tone is detectable in about 15% of cases. Fetal distress appears early in the condition in approximately 50% of cases. The infants who live have a 40 to 50% incidence of illness. Concealed vaginal bleeding in pregnancy, excessive loss of blood resulting in shock, absence of labor, a closed cervix, and delayed diagnosis and treatment are unfavorable factors that may increase the risk of maternal or fetal death.

Summary

The challenge the EMS provider faces is that the the true amount of blood being lost may be occult (hidden), or difficult to reliably assess due to physiological norms related to pregnancy. Learn from the issues presented in the legal case presentation and the unique physiological considerations that apply to all pregnant women. Remember the rule for EMS is: Any pregnant woman, especially after the first trimester, who presents with abnormal bleeding (spotting or frank bleeding), with or without pain, must be treated, stabilized and promptly transported for OB evaluation. Unlike first trimester bleeding, second and third trimester bleeding is most often secondary to premature separation of the placenta. Placenta previa is another serious cause of bleeding. Treat these patients like you would treat any hemorrhagic shock patient, limit field time, and keep in mind some of the special considerations for pregnant women. Oxygen administration, fluid resuscitation and aggressive treatment based on a high index of suspicion or known diagnosis are warranted.

Coming next edition: Part Three: The Low Down on Pregnancy Induced Hypertension, Eclampsia and other complications

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References:

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