Shock: Symptoms, Causes & Types

Table of Contents:

1. Introduction
2. What is Shock?
3. What Is Hypoxia And How It Relates To Shock?
4. Types of Shock and Their Causes 
5. Symptoms of Shock
6. First Aid For Shock
7. Final Thoughts

Shock is a severe disorder in which the circulatory system fails to deliver sufficient oxygenated blood to the body’s tissues and organs. This inadequate concentration of oxygen in the blood is called hypoxia. One of the main causes of hypoxia is a lack of oxygen, which can kill cells and lead to major organ failure. 

The onset of shock can be extremely sudden, and it can rapidly worsen in the absence of care. Shock is not only a prevalent disorder but also a highly perilous one, with several forms affecting hundreds of thousands of people each year. For instance, septic shock develops in about 300 cases per 100,000 annually, with an almost 50% mortality rate in the United States alone.  

The article provides a detailed overview of shock and its types. It also discusses the major causes of shock and its interrelationship with hypoxia.

What is Shock and its Causes?

Shock is a life-threatening situation arising from acute circulatory failure. The blood pressure falls, which decreases the amount of oxygen and other nutrients supplied to vital organs like the brain, heart, and lungs.  Generally, shock is attributed to the following causes:

• Uncontrolled Bleeding
• Spinal Injury
• Blood Loss
• Trauma
• Heatstroke
• Severe Burns
• Severe Infection
• Allergic Reactions
• Poisoning. 

The shock can induce cellular and tissue hypoxia, which can lead to cellular death with consequent organ dysfunction. If not treated, shock rapidly becomes irreversible and culminates in multiorgan failure and death.

Consequences of Shock 

The primary issue in shock is decreased blood flow to crucial tissues. When blood flow decreases and cells don’t receive enough oxygen for aerobic metabolism, they switch to anaerobic metabolism. This causes higher levels of carbon dioxide and lactate in the blood. 

• Cellular function decreases with continued shock, which results in irreversible cell harm and death. 
• In areas of decreased blood flow, shock can activate both the inflammatory and clotting processes. 
• Blood pressure may not be consistently low at the beginning of shock (although hypotension will occur if shock is not treated). Likewise, shock is not present in all patients who have low blood pressure. The extent and effects of low blood pressure differ based on how well the body compensates physiologically and the patient’s pre existing conditions. 
• A slight drop in blood pressure that is easily endured by a younger or generally healthy individual may cause serious brain, heart, or kidney issues in an older person with substantial hardening of the arteries.

What Is Hypoxia And How It Relates To Shock?

Hypoxia is attributed to a decrease in oxygen supply to the body’s tissues and organs. It may affect diverse parts of the body, and when not treated for a very long period, it may lead to serious complications like organ failure and even death.

Shock lowers the amount of oxygen supplied to the cells, leading to hypoxia. If a patient is in shock, then their circulatory system gets compromised, either due to low blood volume, poor cardiac function, or malfunctioning veins. Therefore, the circulation of oxygenated blood to organs and tissues is not well carried out. This can lead to a self-perpetuating cycle of shock from poor perfusion that further deteriorates the patient’s condition.

Types of Hypoxia

The most common causes of hypoxia are lung diseases, serious anemia, poisoning, heart failure, going to high altitude places, or circulatory shock. Treatment must, therefore, be offered immediately to prevent permanent damage or even death. Here are the types of Hypoxia: 

1. Hypoxic Hypoxia: Hypoxic Hypoxia is very common in high altitudes, where less oxygen is available in the atmosphere. It can lead to advanced lung diseases like COPD (Chronic Obstructive Pulmonary Disease).
2. Anemic Hypoxia: This is a state caused by the inability of the blood to transport sufficient oxygen. This could be due to a low count of red blood cells or hemoglobin. Carbon monoxide poisoning can also cause anemic hypoxia as it binds to hemoglobin with more affinity than oxygen.
3. Static Hypoxia: It is also referred to as circulatory hypoxia, which results from the failure of blood flow to deliver oxygen to cells. This may be due to cardiac failure or shock.
4. Histotoxic Hypoxia: It is a condition in which cells cannot use oxygen supplied into the tissues by circulation. This generally takes place due to poisons like cyanide, which stop cells from respiring.

Types of Shock and Their Causes 

When left untreated, shock can be fatal as it is the ultimate symptom of numerous intricate etiologies. Shock can be broadly classified into four categories: distributive, hypovolemic, cardiogenic, and obstructive. The final result of shock is a manifestation of the diverse etiologies that can contribute to each of these categories.

1. Distributive Shock

A medical emergency known as distributive shock, also known as vasodilatory shock, occurs when the heart, brain, and kidneys do not receive enough blood. During distributive shock, blood vessels are highly dilated (flaccid or relaxed), which lowers blood pressure and restricts blood flow to major organs. Here are the types of distributive shock include:

• Septic Shock: 

Sepsis is an organ failure that could be life-threatening because of an unbalanced host reaction to infection. This type of sepsis involves serious problems with the circulatory system, cells, and metabolism. This leads to tissue hypoperfusion, which shows up as low blood pressure and needs vasopressor therapy and high lactate levels.

• Anaphylactic Shock: 

Anaphylactic shock occurs due to a severe allergic reaction controlled by immunoglobulin E (Ig-E). This response causes the patient’s heart to stop beating and their bronchi to narrow, making it hard for them to breathe. The immediate hypersensitivity responses can happen anywhere from seconds to minutes after the inciting antigen is presented.

• Neurogenic Shock: 

Neurogenic shock can happen due to a disruption in the brain or spinal cord. The main cause is a disruption in the autonomic system, which leads to changes in vagal tone and lower vascular resistance.

• Endocrine Shock: 

Vascular dilation can happen in mineralocorticoid deficit because of increased vascular tone and hypovolemia caused by aldosterone insufficiency. These conditions include adrenal failure, Addisonian crisis, and myxedema.

2. Hypovolemic Shock

Hypovolemic shock is marked by less blood volume inside the blood vessels and more help from the systemic veins. It’s a way for the body to keep blood flowing during the early stages of shock. In the later stages of shock, as the body’s volume lowers, cardiac output also drops, which shows up as low blood pressure. Hypovolemic shock occurs in two ways:

• Hemorrhagic Shock: 

Hemorrhagic shock can happen when blood loss lowers the amount inside the blood vessels. Most of the time, blunt or penetrating injuries, such as multiple fractures without damage to blood vessels, cause hemorrhagic shock.

• Non-hemorrhagic Shock: 

This type of shock occurs when the body loses fluids other than blood, and the blood volume drops. Due to salt and water loss, volume depletion can happen in many body parts. Conditions like diarrhea, vomiting, external drainage, heatstroke, and more can cause it.

3. Cardiogenic Shock

Cardiogenic shock occurs when the heart fails to pump a sufficient amount of blood, causing the circulatory system to stop operating. Moreover, It can also occur as a result of sudden ischemic or nonischemic cardiac events.

Acute myocardial infarction is the most common cause of cardiogenic shock. It can happen in 5 to 10 percent of people who have had an acute myocardial infarction, which is up to 70% of cases. Cardiogenic shock can seriously damage cells and multiple organ systems, reduce metabolism, and even kill the person. These are the different kinds of cardiogenic shock:

• Cardiomyopathic: 

The shock is caused by heart problems like myocardial infarction, heart failure getting worse quickly, cardiac death, prolonged ischemia, or cardiopulmonary bypass.

• Arrhythmic: 

Atrial and ventricular tachyarrhythmias and bradyarrhythmia can cause sudden drops in blood pressure. Low blood pressure often plays a role in shock states. When big rhythm problems hurt the heart’s output too much, a person may go into cardiac arrest.

• Mechanical: 

Some mechanical problems that can lead to cardiogenic shock include severe aortic or mitral valve insufficiency and acute valvular defects. These can be caused by the bursting of a papillary muscle or chordae tendineae, the ascending aorta cutting backward into the aortic valve ring, or an abscess of the aortic ring.

4. Obstructive Shock

Blood and oxygen cannot reach your organs if you have obstructive shock. The issue that prompted this emergency, such as a blood clot or collapsed lung, needs to be treated right away. Pulmonary Vascular: 

It is caused by a reduction in the left heart’s ability to receive blood from the right heart. Severe pulmonary hypertension and hemodynamically significant pulmonary embolism are two examples.

Symptoms of Shock

The symptoms of shock depend upon the type and cause of shock and may develop over time after an injury. Shock can cause long-lasting consequences. Some common signs and shock symptoms include:

• Skin: Pale, cool, wet, or ashy skin. The feet and hands may appear light blue or pale. The lips and nails may appear greyish or bluish.
• Breathing: Fast, shallow, too rapid breathing, difficulty moving.
• Pulse: Irregular, very fast, or weak pulse rate.
• Mental status change: Confused, sleepy, less alert, anxious, agitated, restless. Dizziness, weakness, or lightheadedness.

Other symptoms of shock include thirst or dry mouth, nausea or vomiting, and dark or decreased urination.

First Aid For Shock

Shock needs prompt treatment, as delay in first-aid can be life-threatening. Insufficient oxygen can impair the body’s ability to function and even result in death. However, after a patient’s condition stabilizes, some complementary and alternative therapies (CAM) may be used in addition to traditional treatment to help prevent shock. Here are some first-aid steps you can take if someone is in shock:

• Step 1: Assess the situation using the DRSABCD (Danger, Response, Airway, Breathing, and Circulation) Action Plan.
• Step 2: If the person is conscious, he should be laid on his back and made as comfortable and warm as possible. It can also elevate her legs 6–12 inches above heart level using a chair, stool, or box unless he has injuries with fractures or snakebite. This can relieve the blood supply to the brain, lungs, and heart.
• Step 3: Loosen tight clothing around the neck, chest, and waist so that he does not cut off his blood flow.
• Step 4: If there is definite bleeding, stop by pressing a clean cloth or pad firmly on the wound. If a person is bleeding from the mouth or vomits, turn them on the other side to prevent choking.
• Step 5: When a person goes into shock, the body shuts down the blood supply to the extremities and supplies it to the vital organs, making a person feel cold. Hence, you should keep the person warm. 
• Step 6: Call for emergency help and describe that you believe the person is in shock. Try to describe what you believe caused the shock and share your location so that they can reach out to you as soon as possible. 
• Step 7:  While waiting for help to arrive, check to see if the person is breathing. If they’re not breathing, start rescue breathing and CPR. Observe the patient for signs of response.

Final Thoughts

Shock is an extremely dangerous situation that, if not handled promptly, can result in death. To treat shock properly, it is essential to understand the types and causes of shock. The heart and brain are most severely affected due to shock. This can require people to be skilled at CPR or AED usage under emergency conditions. 

Being ready means more than just knowing what happens in a shock or having the right tool. It also means having the courage and skills to know when and how to use it. To save a life tomorrow, you might be the person who makes the difference by training today.

Read More: 

First Aid for Choking: Essential Steps to Save Lives

The Ultimate Guide to Infant CPR Ratios