TYPES OF SHOCK

1- Cardiogenic shock: due to acute heart failure, myocardial infarction, anaesthesia, cardiac arrest, arrhythmias …..etc

2- Oligaemic (hypovolaemic) shock: due to depletion of blood volume by:

• Blood loss: haemorrhage or trauma.
• Plasma loss: burns.
• Water loss: dehydration.

3- Vasogenic shock: due to widespread vasodilatation by:

• Reflex vasomotor paralysis: severe pain or excitement (neurogenic shock).
• Sympathetic paralysis: spinal anaesthesis (spinal shock).
• Capillary paralysis: histamine release arises from anaphylactic reactions (anaphylactic shock).

4- Septic shock:bacteraemia/endotoxaemia

CLINICAL PICTURE OF SHOCK

• Ill distressed or apathetic patient.
• Cold clammy sweat.
• Pale grayish skin.
• Collapsed veins: indicate severe oligaemia.
• Oliguria (less than 0.5 ml / min.).
• Pulse : rapid feeble pulse.
• Blood pressure: low blood pressure.
• Temperature: subnormal temperature, cold nose (severe VC), high rectal temperature is a warning sign.
• Consciousness : coma or semicoma is dangerous signs.
• Respiration: tachyapnoea (over 35/min. is serious). 

INVESTIGATIONS 

I- Clinical:

Estimation of volume deficit from pulse and blood pressure

2. Estimation of urine output:

• Persistent oliguria in spite of a satisfactory Bl. Pressure and CVP indicate acute tubular necrosis.
• Polyuria with increase blood urea indicates high output renal failure.

3. Central venous pressure (CVP):

• Decreased in oligaemic and neurogenic shock.
• Increased in cardiogenic shock. 

II- Laparotory:

1. Arterial blood gases:

• O2 tension: indicate the adequacy of oxygenation, normally = 100, if decrease indicate hypoperfusion.
• CO2 tension: indicate the adequacy of ventilation, normally = 40, if increase indicate hypoventilation.
• PH: normally = 7.4.

2. Haematocrite value:

• Haemoconcentration (increase HC) is an early sign of shock.
• Differentiate shock (increase HC) from haemorrhage (decrease HC).

3. Arterial blood lactate:

• Increase in shock.

III- Radiological:

Estimation cardiac Output: by radioisotope study.

FIRST – AID MANAGEMENT OF SHOCKED PATIENT

Aim of treatment:

• Restore normal tissue perfusion.
• Correction of hypotension.
• Correction of microcirculation.
• Maintain CVP around 5 cm saline.
• Maintain urine output around 0.5 ml/min.
• Maintain haematocrite value around 35%.

First – aid measures:

• Arrest of bleeding.
• Dressing of open wounds.
• Splintage of fractures.
• Maintain of open airway.
• Correction of chest injury.
• O2 therapy.
• Morphia : relieves pain, alleys anxiety, and reduces tissue metabolism.
• Head-down (Trendelenburg) position, or legs elevation with maintaining the trunk in the supine position.
• Maintain body heat by blankets.
• IV cannula with lactated Ringer’s solution,
• CVP catheter.

Fluid replacement:

• Colloids: Blood, human plasma, Dextran.
• Crystalloids: Saline, Glucose, Lactated Ringer’s solution.

Drainage of Abscesses and Septic Collections. 

Adjuvant treatment: