CEN1 Shock_Hematology

Objectives:
At the completion of this section, the learner will be able to:
 Define shock
 Differentiate the signs of compensatory shock from decompensatory shock
 List the three forms of distributive shock
The CEN exam contains nine questions on shock which involve the following topics:
 Cardiogenic shock
 Distributive shock (e.g. anaphylactic, septic, neurogenic shock)
 Hypovolemic
 Obstructive (e.g. pericardial tamponade, tension pneumothorax)
 Shock (not specific)
 Shock (lack of oxygen to the tissues)
o Hypovolemic shock – Decreased cellular perfusion secondary to lack of circulating volume
o Cardiogenic shock – Decreased cellular perfusion secondary to failure of the central pump
o Distributive shock – Decreased cellular perfusion secondary to maldistribution of the oxygen to the periphery
o Obstructive shock – Decreased cellular perfusion secondary to obstruction of blood into or out of the ventricles (e.g.
pulmonary embolism, pericardial tamponade, tension pneumothorax)
 Obstructive shock
Type of obstruction Treatment
Pregnancy Roll the patient to her side
Tension pneumothorax Chest tube/needle decompression
Cardiac tamponade Pericardiocentesis
Pulmonary embolism Thrombolytics
Aortic aneurysm Surgical intervention
Aortic stenosis Surgical intervention
Excessive positive end expiratory pressure
(PEEP)
Readjust ventilator settings
 Hypovolemic shock
o Early (compensatory) shock
Sympathetic nervous system (adrenergic
system)
Parasympathetic nervous system (cholinergic
system)
Alpha
receptors
 Vasoconstriction
 Glucogeonolysis
 Diaphoresis
 Vasodilation
 Gluconeogenesis
 Dry skin
Beta-one
receptors
  heart rate
  contractility
  automaticity
  heart rate
  contractility
  automaticity
Beta-two
receptors
  respiratory rate
 Bronchodilation
  respiratory rate
 Bronchoconstriction
Certified Emergency Nurse (CEN) Exam Review Jeff Solheim
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Definition:
Agonist – St imulates a system
Antagonist – Diminishes the response of a system
 Late (decompensatory shock
 Inflammatory mediators are released in response to either foreign invasion of tissue or tissue damage. They
have three main courses of action:
 Vasodilation
 Increased capillary permeability
 Increased coagulation
Clinical manifestations of shock
o Treatment
 Fluid replacement
 Crystalloids
o Isotonic crystalloids given at a 3:1 replacement ratio.
o Generally, a bolus of 1 – 2 liters of crystalloid solution is administered to a patient with
indications of hypovolemic shock.
o Pediatric patients are given boluses at a rate of 20 mL/kg.