1 Shock Terry White, RN

2 SHOCK Inadequate perfusion (blood flow) leading to inadequate oxygen delivery to tissues

3 Physiology l Basic unit of life = cell l Cells get energy needed to stay alive by reacting oxygen with fuel (usually glucose) l No oxygen, no energy l No energy, no life

4 Cardiovascular System l Transports oxygen, fuel to cells l Removes carbon dioxide, waste products for elimination from body Cardiovascular system must be able to maintain sufficient flow through capillary beds to meet cell’s oxygen and fuel needs

5 Flow = Perfusion Adequate Flow = Adequate Perfusion Inadequate Flow = Inadequate Perfusion (Hypoperfusion) Hypoperfusion = Shock

6 What is needed to maintain perfusion? l Pump l Pipes l Fluid Heart Blood Vessels Blood

7 How can perfusion fail? l Pump Failure l Pipe Failure l Loss of Volume

8 Types of Shock and Their Causes

9 Cardiogenic Shock l Pump failure l Heart’s output depends on How often it beats (heart rate) How hard it beats (contractility) l Rate or contractility problems cause pump failure

10 Cardiogenic Shock l Causes Acute myocardial infarction Very low heart rates (bradycardias) Very high heart rates (tachycardias) Why would a high heart rate caused decreased output? Hint: Think about when the heart fills.

11 Neurogenic Shock l Loss of peripheral resistance l Spinal cord injured l Vessels below injury dilate What happens to the pressure in a closed system if you increase its size?

12 Hypovolemic Shock l Loss of volume l Causes Blood loss: trauma Plasma loss: burns Water loss: Vomiting, diarrhea, sweating, increased urine, increased respiratory loss If a system that is supposed to be closed leaks, what happens to the pressure in it?

13 Psychogenic Shock l Simple fainting (syncope) l Caused by stress, pain, fright l Heart rate slows, vessels dilate l Brain becomes hypo- per fused l Loss of consciousness occurs What two problems combine to produce hypoperfusion in psychogenic shock?

14 Septic Shock l Results from body’s response to bacteria in bloodstream l Vessels dilate, become “leaky” What two problems combine to produce hypoperfusion in septic shock?

15 Anaphylactic Shock l Results from severe allergic reaction l Body responds to allergen by releasing histamine l Histamine causes vessels to dilate and become “leaky” What two problems combine to produce hypoperfusion in anaphylaxis?

16 Shock: Signs and Symptoms l Restlessness, anxiety l Decreasing level of consciousness l Dull eyes l Rapid, shallow respirations Why are these signs and symptoms present? Hint: Think hypoperfusion l Nausea, vomiting l Thirst l Diminished urine output

17 Shock: Signs and Symptoms l Hypovolemia will cause Weak, rapid pulse Pale, cool, clammy skin l Cardiogenic shock may cause: Weak, rapid pulse or weak, slow pulse Pale, cool, clammy skin l Neurogenic shock will cause: Weak, slow pulse Dry, flushed skin l Sepsis and anaphylaxis will cause: Weak, rapid pulse Dry, flushed skin Can you explain the differences in the signs and symptoms?

18 Shock: Signs and Symptoms l Patients with anaphylaxis will: Develop hives (urticaria) Itch Develop wheezing and difficulty breathing (bronchospasm) What chemical released from the body during an allergic reaction accounts for these effects?

19 Shock: Signs and Symptoms Shock is NOT the same thing as a low blood pressure! A falling blood pressure is a LATE sign of shock!

20 Treatment l Secure, maintain airway l Apply high concentration oxygen l Assist ventilations as needed l Keep patient supine l Control obvious bleeding l Prevent loss of body heat

21 Treatment l Elevate lower extremities 8 to 12 inches in hypovolemic shock l Do NOT elevate the lower extremities in cardiogenic shock Why the difference in management?

22 Treatment l Administer nothing by mouth, even if the patient complains of thirst

23 Bleeding Significance l If uncontrolled, can cause shock and death

24 Identification of External Bleeding l Arterial Bleed Bright red Spurting l Venous Bleed Dark red Steady flow l Capillary Bleed Dark red Oozing What is the physiology that explains the differences?

25 Control of External Bleeding l Direct Pressure gloved hand dressing/bandage l Elevation l Arterial pressure points

26 Arterial Pressure Points l Upper extremity: Brachial l Lower extramity: Femoral

27 Internal Bleeding l Can occur due to: Trauma Clotting disorders Rupture of blood vessels Fractures (injury to nearby vessels)

28 Internal Bleeding Can result in rapid progression to hypovolemic shock and death

29 Internal Bleeding l Assessment Mechanism? Signs and symptoms of hypovolemia without obvious external bleeding

30 Internal Bleeding l Signs and Symptoms Pain, tenderness, swelling, discoloration at injury site Bleeding from any body orifice

31 Internal Bleeding l Signs and Symptoms Vomiting bright red blood or coffee ground material Dark, tarry stools (melena) Tender, rigid, or distended abdomen

32 Internal Bleeding l Management Open airway High concentration oxygen Assist ventilations Control external bleeding Stabilize fractures Transport rapidly to appropriate facility