What Happens When Blood Volume Decreases
Losing a significant quantity of blood triggers the condition known as Hypovolemia, which can lead to hypovolemic shock. However, Hypovolemia is not only limited to blood loss but also includes fluid loss, typically 15% in a short period. This affects the blood volume, leading to a shortage of blood circulating throughout the body.
This condition is dangerous and life-threatening because blood circulates essential nutrients, oxygen, and hormones to all organs and tissues.
Additionally, it is responsible for regulating body temperature.
Thus, a shortage of blood may lead to organ failure and Hypovolemic shock. Common causes include extreme blood loss, extreme dehydration, and sepsis/septic shock.
Causes of hypovolemic shock from bleeding include:
- Internal bleeding – Ulcers, Large blood vessel rupture, Ectopic pregnancy, Ruptured ovarian cyst, Placental Abruption, and Burns.
- External bleeding – Heavy bleeding, Head and neck cuts, Broken bones around the hips
- Endometriosis
- Organ damage
Causes not from bleeding
- Severe Dehydration from Diarrhea and vomiting, extreme sweating (hyperhidrosis), lack of/low fluid intake
- Kidney failure, diuretics, and excessive urination (polyuria)
- Extreme fever
- Gastrointestinal problems like stoma or fistulas
- Fluid accumulation in parts of the body like pancreatitis, liver cirrhosis, intestinal obstruction
The severity of hypovolemic shock depends on the following:
Age
Age weakens the body’s defense. A minor issue for younger people may prove fatal for an older person.
The swiftness of blood and fluid loss
Hypovolemia becomes life-threatening quickly when fluid loss (blood or otherwise) outpaces your ability to replenish it. Losing over 50% of fluids can be fatal.
Overall health
For people with existing health issues, Hypovolemia becomes even more dangerous. It can worsen pre-existing conditions or be quickly overwhelmed by them, leading to fatal complications.
Severity of Blood and Fluid Loss
Blood loss dictates the severity of Hypovolemia. Early stages involve a 15% loss (750 ml) with mild symptoms. As loss worsens (30-40%, 1500-2000 ml), symptoms intensify, and the risk of complications rises. Losing over 40% of blood volume is life-threatening.
Symptoms
Dizziness, fatigue, extreme thirst, chest and abdomen pain, increased heart rate (Tachycardia), low blood pressure (hypotension), disorientation, clammy skin/sweating, low urine output (Oliguria), fainting (syncope), shock, multiple organ failure, and death.
How to Diagnose Hypovolemic Shock
Physical examination
Due to the amount of blood being lost, Hypovolemia from external bleeding may be easy to diagnose. However, internal bleeding and other internal causes may be more challenging to diagnose. As such, your doctor would assess your breathing, temperature, heart rate, pulse, and blood pressure.
This condition requires immediate medical attention.
Quelling external blood loss, oxygenation, and intravenous fluid replacement are crucial. For severe blood loss (above 30%), a blood transfusion may also be required. Sometimes, surgery may be necessary to fix any damages.
In conclusion, Hypovolemia may cause various effects based on severity, so it is essential to seek medical attention immediately.
