Management of Shock
Shock is a serious medical condition where the tissue perfusion is insufficient to meet demand for oxygen and nutrients because the body is not getting enough blood flow. This can damage multiple organs and can get worse very rapidly. This hypoperfusional state is a life-threatening medical emergency and one of the leading causes of death for critically ill people.
Major classes of shock include :
1. Hypovolemic Shock (caused by inadequate blood volume)
Hypovolemic shock is an emergency condition in which severe blood and fluid loss makes the heart unable to pump enough blood to the body. This type of shock can cause many organs to stop working.
Blood loss can be due to bleeding from cuts or other injury or internal bleeding such as gastrointestinal tract bleeding. The amount of blood in your body may drop when you lose too many other body fluids, which can happen with diarrhea, vomiting, burns, and other conditions.
Symptom are :
- Anxiety, restlessness, altered mental state due to decreased cerebral perfusion and subsequent hypoxia.
- Hypotension due to decrease in circulatory volume.
- A rapid, weak, thready pulse due to decreased blood flow combined with tachycardia.
- Cool, clammy skin due to vasoconstriction and stimulation of vasoconstriction.
- Rapid and deep respirations due to sympathetic nervous system stimulation and acidosis.
- Hypothermia due to decreased perfusion and evaporation of sweat.
- Thirst and dry mouth, due to fluid depletion.
- Fatigue due to inadequate oxygenation.
- Cold and mottled skin (cutis marmorata), especially extremities, due to insufficient perfusion of the skin.
Therapy are include :
- Maintain or increase intravascular volume, In hypovolaemic shock, caused by bleeding, it is necessary to immediately control the bleeding and restore the victim’s blood volume by giving infusions of balanced salt solutions. Blood transfusions are necessary for loss of large amounts of blood (e.g. greater than 20% of blood volume), but can be avoided in smaller and slower losses. Hypovolaemia due to burns, diarrhoea, vomiting, etc. is treated with infusions of electrolyte solutions that balance the nature of the fluid lost.
- Decrease any future fluid loss via I.V fluid regimen
- Give supplementary O2 therapy to commence replacement of fluids via the intravenous route.
2. Cardiogenic shock (associated with heart problems)
Cardiogenic shock is a disease state where the heart is damaged enough that it is unable to supply sufficient blood to the body. Most common causes are :
a). acute myocardial infarction
b). dilated cardiomyopathy, This is a serious disease in which the heart muscle becomes inflamed (enlarged and stretched) and doesn’t work as well as it should.
c). acute myocarditis
Symptoms are :
similar to hypovolaemic shock but in addition:
- Distended jugular veins due to increased jugular venous pressure.
- Absent pulse due to tachyarrhythmia.
Therapy are include :
The main goals of the treatment of cardiogenic shock are the re-establishment of circulation to the myocardium, minimising heart muscle damage and improving the heart’s effectiveness as a pump.
- Oxygen (O2) therapy to reduces the workload of the heart by reducing tissue demands for blood flow.
- Administration of cardiac drugs
- Increase heart’s pumping action through medication such as Dopamine, dobutamine, epinephrine, norepinephrine, amrinone
3. Septic shock (associated with infections)
Septic shock is a serious condition that occurs when an overwhelming infection leads to low blood pressure and low blood flow. The brain, heart, kidneys, and liver may not work properly or may fail.
Most common of this case may it’s happened to the patients with Meningococcemia, Waterhouse-Friderichsen syndrome, DIC (disseminated intravascular coagulation), Multiple organ dysfunction syndrome (MODS), Acute Respiratory Distress Syndrome (ARDS).
Symtomps are :
similar to hypovolaemic shock except in the first stages:
- Pyrexia and fever, or hyperthermia, due to overwhelming bacterial infection.
- Vasodilation and increased cardiac output due to sepsis.
- Therapy are include :
- Restore intravascular volume via I.V fluid
- Give supplemental O2 therapy
- Identify and control source of infection
- Administer antibiotic
- Remove risk factor for infection
4. Neurogenic shock (caused by damage to the nervous system)
Neurogenic shock is shock caused by the sudden loss of the sympathetic nervous system signals to the smooth muscle in vessel walls. This can result from severe central nervous system (brain and spinal cord) damage. With the sudden loss of background sympathetic stimulation, the vessels suddenly relax resulting in a sudden decrease in peripheral vascular resistance and decreased blood pressure.
Signs and symptoms:
similar to hypovolaemic shock except in the skin’s characteristics. In neurogenic shock, the skin is warm and dry.
Therapy are include :
- Large volumes of fluid may be needed to restore normal hemodynamics
- Vasopressors (Norepinephrine)
- Atropine (speeds up heart rate and Cardiac Output)
5. Anaphylactic Shock (caused by allergic reaction)
Anaphylaxis is an severe, whole-body allergic reaction. After an initial exposure to a substance like bee sting toxin, the person’s immune system becomes sensitized to that allergen. On a subsequent exposure, an allergic reaction occurs. This reaction is sudden, severe, and involves the whole body.
Common causes include insect bites/stings, horse serum (used in some vaccines), food allergies, and drug allergies.
Symptoms of anaphylaxis are related to the action of Immunoglobulin E and other anaphylatoxins, which act to release histamine and other mediator substances from mast cells (degranulation). In addition to other effects, histamine induces vasodilation of arterioles and constriction of bronchioles in the lungs, also known as bronchospasm (constriction of the airways).
Symptoms can include the following :
Polyuria, respiratory distress, hypotension (low blood pressure), encephalitis, fainting, unconsciousness, urticaria (hives), flushed appearance, angioedema (swelling of the lips, face, neck and throat), tears (due to angioedema and stress), vomiting, itching, diarrhea, abdominal pain, anxiety, impending sense of doom.
Therapy are include :
- Identify and remove causative antigen
- Administer counter-mediators such as anti-histamine
- Oxygen therapy and I.V fluid replacement