1. TRANSITION SERIES Topics for the Advanced EMT CHAPTER Shock 35

2. Objectives Review the rates for hypoperfusion and shock. Review aerobic and anaerobic metabolism. Discuss the pathophysiological basis for the stages of shock. Define treatment strategies for a patient with shock.

3. Introduction “Shock” coined in 1743 to represent what happens at the cellular level when perfusion is bad. Now it has varied meanings, so the term “hypoperfusion” has been introduced.

4. Epidemiology Since “shock” is a response to another body dysfunction, there is not a clear estimation of “shock” rates. It is known, though, that when a shock state does occur (for whatever reason), the death rate is normally >20%. Some etiologies of shock cause 90% mortality.

5. Pathophysiology Hypoperfusion can occur due to multiple etiologies. –Cardiac –Volume –Vascular

6. Pathophysiology (cont’d) In any instance, the final common pathway is deterioration of cellular oxygenation. –Aerobic metabolism –Anaerobic metabolism

7. Etiologies of Shock

8. Etiology of shock: fluid loss

9. Etiology of shock: pump failure

10. Etiology of shock: vasodilation

11. Pathophysiology (cont’d) Stages of shock –Initial stage –Compensatory (nonprogressive) stage  Compensatory mechanisms –Progressive (decompensatory) stage –Refractory (irreversible) stage

12. Compensatory Mechanisms in Hypoperfusion

13. Effects of Shock on Body Organs and Systems

14. Recognizing the severity of shock

15. Assessment Findings Depending upon stage of shock: –Tachycardia and tachypnea –Anxious, aggressive, altered mental status –Narrowing pulse pressure –Muscles become weak, then limp

16. Assessment Findings (cont’d) Depending upon stage of shock (continued) –Skin becomes cool and pale, typically diaphoretic –Final stages will have a dropping systolic blood pressure, excessive tachycardia, unresponsiveness and death

17. Categories and types of shock

18. Characteristics of the Major Categories of Shock

19. Emergency Medical Care Spinal immobilization considerations –Traumatic incidents Airway considerations –Ensure open airway. –Maintain airway if needed.

20. Emergency Medical Care (cont’d) Breathing considerations –Use high-flow oxygen if breathing adequately. –PPV at either 8-10 or 10-12 (based on pulse).

21. Emergency Medical Care (cont’d) Circulatory considerations –Importance of pulse checks. –If CPR warranted, push hard and fast. –If major bleed present (whether arterial or venous), control it as soon as possible. Other considerations –Maintain normothermia. –Body positioning.

22. Emergency Medical Care (cont’d) Intravenous therapy –Do not delay transport to initiate an IV. –If volume expansion is needed, use a large-bore catheter such as a 14 or 16 gauge. –Administer IV fluids based on the clinical presentation and as your protocol allows.

23. Emergency Medical Care (cont’d) Volume Loss Etiology (Hypovolemia) –Uncontrolled hemorrhage - infuse fluid at a rate to maintain a systolic blood pressure of 80 to 90 mmHg or until radial pulses are able to be palpated. –Controlled hemorrhage - infuse fluid to maintain the systolic blood pressure above 90 to 100 mmHg.

24. Emergency Medical Care (cont’d) Vasodilation Etiology –Increase vascular resistance by decreasing the vessel size. –Fill the vessel with fluid. –As an Advanced EMT, you will not likely be able to administer vasopressors to constrict vessels; however, you can infuse fluids to fill the vascular space.

25. Emergency Medical Care (cont’d) Cardiogenic Etiology –Typically the patient is normovolemic and is experiencing difficulty in moving the existing volume of blood. –Restrict fluid administration to a keep- open rate once the intravenous line is initiated.

26. Case Study During a local cage-fighting event, one of the fighters was lifted and thrown down onto the mat, landing on his head and back. The fighter quit moving so you were called in to assess the patient. He is a young male, 22-23 years old, 185 pounds, very muscular.

27. Case Study (cont’d) Scene Size-Up –Standard precautions taken. –Scene is safe, obvious struggle with the fighting. –Patient lying supine on floor of ring. –No entry problems, egress may be hampered due to large audience present.

28. Case Study (cont’d) Primary Assessment Findings –Patient responsive. –Airway appears open, patient able to speak. –Breathing is rapid and shallow, breath sounds present. –Carotid and radial pulses present, radial very weak.

29. Case Study (cont’d) Primary Assessment Findings –Peripheral skin is warm, diaphoretic. –No major bleeds or angulations noted, patient not moving extremities.

30. Case Study (cont’d) Is this patient a high or low priority? Why? What interventions should be provided at this time?

31. Case Study (cont’d) What is the significance of the radial pulse being weak as compared to the carotid? What could be the etiologies of shock that could create this finding?

32. Case Study (cont’d) Medical History –Patient states none Medications –Various muscular training supplements Allergies –None

33. Case Study (cont’d) Pertinent Secondary Assessment Findings –Pupils reactive to light. –Airway patent and maintained by the patient. –Breathing is rapid, alveolar sounds diminished. –Peripheral pulse now absent, carotid now becoming weaker.

34. Case Study (cont’d) Pertinent Secondary Assessment Findings (continued) –Skin warm and dry, no motor or sensory motion below shoulders. –B/P 100/50, HR 62, RR 26. –SpO 2 95% on room air, 99% on oxygen.

35. Case Study (cont’d) Is this patient in a state of shock? If yes, what stage of shock? Are there now findings that would cause you to refine your field impression?

36. Case Study (cont’d) What normal compensatory mechanism for shock is not active in this patient? Why would this etiology of shock cause the patient's respiratory status to be what it is?

37. Case Study (cont’d) Care provided: –Patient kept supine. –High-flow oxygen via NRB mask. –Full spinal immobilization done very carefully. –Paramedic intercept started early. –Patient packaged and taken to ambulance via wheeled cot. –Transport to hospital initiated.

38. Summary Hypoperfusion is going to be one of the most common syndromes seen by the Advanced EMT. Since this is the final common pathway for all types of shock, the Advanced EMT must be able to recognize the cause of shock – not just the symptoms, in order to provide the best care.