Types of Shock

According to the international classification, there's 4 types of shock :
i) Hypovolemic
ii) Cardiogenic
iii) Distributive
iv) Obstructive

We can grade the severity of the shock.This approximates to the effective loss of blood volume. The blood volume does not have to actually be lost from the circulation as an expansion in the volume of the circulatory system (e.g. in septic shock) will render the patient proportionally hypovolaemic.

Grade 1 - loss up to 15% ( ~750ml) ----> mild resting tachycardia

Grade 2 - loss from 15%-30% ( 750-1500ml) ----> moderate tachycardia and narrow pulse pressure

Grade 3 - loss from 30%-40%(1500-2000ml) ----> the compensatory mechanisms begin to fail and
hypotension, tachycardia and low urine output (<0.5ml/kg/hr>.

Grade 4 - loss from 40%-50%(2000-2500ml) ---->profound hypotension will develop and if prolonged will
cause end-organ damage and death

Now the types of shock.

1. Hypovolemic - due to insufficient circulating volume caused by hemorrhage, internal bleeding, severe burns and high output fistula

2. Cardiogenic - due to failure of the muscle of heart to pump efficiently due to MI, arrhythimias, CHF.

3. Distributive - a form of 'relative hypovolemic' due to dilation of blood vessel which diminishes systemic vascular resistance.
eg i) Septic Shock - sepsis with hypotension despite fluid resuscitation, due to vasodilation that caused by systemic infection which usually caused by Gram -ve (E.coli, proteus, Klebsiella) and Gram +ve ( pneumococci, streptococci)

ii) Anaphylactic shock - allergen causing release if histames -> vasodilation and increase capillary permeability-> hypotension.

iii) Neurogenic shock - due to trauma to the spinal cord -> loss of autonomic and motor reflex below the injury level -> no symphatetic action so lead to vessel wall relax uncontrollably, lead to reduce peripheral vascular resistance -> hypotension.

4. Obstructive - when flow of blood is obstructed which impedes the circulation.
eg) i) Cardiac tamponade or constrictive pericarditis - prevent inflow of blood into heart

ii) Tension pneumothorax - increase intrathoracic pressure, reduce blood flow into heart.

iii) Massive PE , Aortic stenosis.

Management of SHOCK

MAIN AIM IS TO RESTORE NORMAL TISSUE PERFUSION

1.Establish Airway and O2 delivery
2.Fluid resuscitation - 2 large 16 size branulla, run Normal Saline@Hartmann fast over 10 mins, 30 mins, 1 hour and then reassess the BP, pulse, urine output.
3. Give adequate analgesic for pain management.
4.Treat mechanical cause if any ( tension pneumothorax, pericardial tamponade)
5. Blood transfusion if indicated
6.Inotropes if indicated
7.Vasopressin if indicated
8.Early antibiotics and rapid identification of infection in septic shock.**

** SIGN to LOOK in Hypotension or blood loss.
1. BP -- reducing trend or less than 90/60( according to my boss, dont just follow the 90/60 rules, always see the dynamics of the BP trend)

2.Pulse -- tachycardic shows that there's insufficient fluid in circulation.

3. Check urine output -- always maintain 30-50 cc/h

4. Check Hb level, if less than 8gm.. always think of tranfusing blood.

5. Do rectal examination in case there's GIT bleed.