Acute Posthemorrhagic Anemia: Symptoms, Causes, And Treatment

What is acute posthemorrhagic anemia?

Also known as acute blood loss anemia, acute posthemorrhagic anemia is a type of acute anemia resulting from a quick loss of blood volume. This blood loss causes a significant drop in red blood cell count. And since red blood cells carry oxygen to the body's cells, it can lead to severe organ damage.

What causes acute posthemorrhagic anemia?

Acute posthemorrhagic anemia is directly caused by loss of blood, which can stem from:

• A traumatic injury involving an artery. This trauma can be due to an accident or even after surgery. Bleeding from a vein can be just as serious as arterial bleeding. However, due to its slow blood flow, blood loss is generally less severe.

• A ruptured aneurysm (an outward bulging caused by a localized and abnormal weak spot on a blood vessel wall)

• Significant damage in either the upper or lower gastrointestinal

• Disseminated intravascular coagulation. This happens when an infection or injury affects blood clotting, which causes overactive clotting followed by internal bleeding or bleeding under the skin.¹

• A ruptured ectopic pregnancy. This happens when a fertilized egg implants outside the uterus, often in a fallopian tube. The tube can then rupture, causing severe internal bleeding.

• Platelet disorders. This disorder is diagnosed when your platelet count is abnormal or your platelets aren’t functioning. Since this disorder can lead to bleeding, it may play a role in the development of posthemorrhagic anemia.

It’s worth remembering that blood loss is the most common cause of anemia.

What are the risk factors for acute posthemorrhagic anemia?

Most cases of posthemorrhagic anemia are caused by traumatic injury. In this sense, engaging in more dangerous occupational or recreational activities is an important risk factor. You can reduce your risk by always following safety protocols and wearing appropriate safety gear when needed.

In general, risk factors include those that increase your risk of conditions that can result in blood loss. 

For example, your risk for an ectopic pregnancy is higher if you:

• Have had one before

• Have had surgery on your fallopian tubes

• Have had any other surgery in the pelvis or abdomen

• Have pelvic inflammatory disease

• Have endometriosis, a condition in which the tissue that lines the womb grows elsewhere in the abdomen

• Smoke

• Are older than 35

• Used assisted reproductive technology

Major gastrointestinal bleeding can be caused by anything from cancer to gastritis or ulcers. Be aware that chronic gastrointestinal bleeding can also cause chronic anemia. 

Also, consider paying attention to risk factors of other conditions that can lead to acute posthemorrhagic anemia since many of them can be modified. Risk factors for these include:

• Aneurysm rupture: smoking, high blood pressure, genetics 

• Disseminated intravascular coagulation: inflammation 

• Platelet disorders: age, excessive drinking, the use of certain medications, including blood thinners and seizure medications   

Acute posthemorrhagic anemia symptoms

Doctors will generally be on the lookout for anemia if you’ve experienced a traumatic injury. Acute posthemorrhagic anemia presents differently depending on how much blood you have lost. It’s divided into four classes:

1. Class I (15% or less blood loss): characterized by increased heart rate and skin that feels cool to the touch

2. Class II (15-30% blood loss): characterized by a higher decrease in pulse pressure accompanied by rapid breathing

3. Class III (30-40% blood loss): characterized by a more accentuated increase in heart rate, a decrease in blood pressure, and a decrease in urine output

4. Class IV (40% blood loss): symptoms presented in previous stages get worse and may result in loss of consciousness. Mortality is high.

The symptoms of acute anemia are different from chronic anemia symptoms such as fatigue. Any of these symptoms are a medical emergency requiring immediate attention.

Complications of acute blood loss anemia

Untreated acute blood loss anemia can lead to hypovolemic shock, which means your heart is unable to pump enough blood to your other organs due to low blood volume. This can cause damage to the kidneys, brain, and other organs and can result in gangrene for the lack of oxygen. Finally, depending on the volume of blood lost, the hypovolemic shock can be fatal.

Treatment of acute blood loss anemia

The treatment recommended depends in part on whether you’re still bleeding.

If you’re still bleeding, an immediate blood transfusion is performed while medical professionals work on the cause of the bleeding. Trying to stop the bleeding first can result in hypovolemic shock. However, if you’re getting somebody who is bleeding medical assistance, stopping the bleeding is vital. Ideally, you want to get the bleeding stopped before medical professionals arrive.

Supplemental oxygen is also sometimes used to help prevent hypoxia before receiving the transfusion. 

After the bleeding is stopped and the transfusion occurs, you will receive treatment to help you recover. You might be placed in a hyperbaric chamber for a couple of days, which has been shown to speed recovery (and can also keep people alive until a blood transfusion can be arranged). You might also receive intravenous fluids, specifically hypertonic saline. 

Finally, you will need to take iron supplements for a period, which may be as long as three to six months. These measures are intended to help your body create more blood to replace what you’ve lost.

Preventing acute blood loss anemia

When an accident occurs, the best way to prevent acute blood loss anemia is to provide proper first aid and call for emergency medical care.

One should apply direct pressure to the wound. Wear latex gloves if available (or non-latex gloves if you’re allergic). Blood-borne infections are a risk any time you’re treating somebody with a bleeding wound. If there’s a foreign object in the wound, do not remove it. Often the object is preventing more bleeding. Tape and bandage the object in place.

Maintain pressure until the bleeding stops. Note that some very minor wounds, such as scalp wounds, can appear to bleed a lot.

If the bleeding is severe, keep the injured body part still. Lay the person flat and raise their feet by about a foot, then cover them with a coat or blanket. Try not to move them.

It isn’t recommended to use a tourniquet unless the bleeding is severe and life-threatening, as it can damage the limb. Apply the tourniquet over the clothing if possible.

Again, always call medical help for severe bleeding or if you’re unable to stop the bleeding quickly. Always call for medical assistance if there’s gravel or dirt in the wound, the wound was caused by a bite (human or animal), or you aren't sure whether the person is up to date on their tetanus vaccinationsCall medical help if you have the symptoms of acute anemia, even if you can't find the source of the bleeding (it’s likely internal). If you suspect you might be pregnant and have low back pain, mild pain in the abdomen, or mild cramping on one side of the pelvis along with vaginal bleeding, call your ob-gyn, as it may be an ectopic pregnancy.

The lowdown

Acute posthemorrhagic anemia is most often caused by a traumatic injury. But it can also be caused by an aneurysm, severe gastrointestinal bleeding, platelet disorders, or ectopic pregnancy. It refers to anemia caused by blood loss, which reduces blood volume and can mean your organs aren’t getting enough oxygen.

It’s a medical emergency. You will likely need a blood transfusion and other treatments to restore blood volume, so it’s important to seek urgent medical assistance. While there are few ways to prevent it, knowing good first aid skills can keep a traumatic injury from turning into acute anemia.