Approach-to-Shock———————————————————————

Emergency Medicine

1. APPROACH TO SHOCK Jonathan Paghubasan Emergency medicinE

2. OBJECTIVES: Identify shock

3. Shock is a state of circulatory insufficiency that creates an imbalance between tissue oxygen supply and oxygen demand resulting in end-organ dysfunction Mechanisms: Hypovolemic Cardiogenic Distributive Obstructive

4. Cardiac Output Inotropy Chronotropy Lusitropy Anrep Effect – increase in afterload Bowditch Effect – heart rate

5. Compensatory Mechanism arteriolar vasoconstriction an increase in heart rate and contractility constriction of venous capacitance vessels release of the vasoactive hormones epinephrine, norepinephrine, dopamine, and cortisol release of antidiuretic hormone and activation of the renin-angiotensin axis

6. Categories of Shock

7. Clinical Features: systemic arterial hypotension; systolic blood pressure <90 mm Hg generalized weakness, lethargy, or altered mental status

8. Early Treatment Airway Breathing Circulation Delivery of oxygen End points of resuscitation

9. Airway Best obtained through endotracheal intubation. Sedatives used to facilitate intubation may cause arterial vasodilatation, venodilation , or myocardial suppression and may result in hypotension

10. Breathing Control of breathing is required when significant tachypnea accompanies shock Mechanical ventilation and sedation allow for adequate oxygenation, improvement of hypercapnia, and assisted, controlled, synchronized ventilation

11. Circulation Fluids Fluid resuscitation should begin with isotonic crystalloid Administer fluid rapidly (over 5 to 20 minutes), in set quantities of 500 or 1000 mL of normal saline, and reassess the patient after each bolus. Modest degree of hypovolemia 20-30ml/kg Septic shock; 6L of crystalloid for the 1 st 24H Vasopressors raising MAP above the 65 to 70 mm Hg range

12. Assuring Adequate Oxygen Delivery Control of oxygen consumption is important in restoring the balance of oxygen supply and demand to the tissue

13. End Points of Resuscitation A goal-directed approach of: MAP >65 mm Hg, C entral venous pressure of 8 to 12 mm Hg, Scvo2 >70 % U rine output >0.5 mL/kg/h

14. Early recognition, intervention, source control, and smooth transitions of care help ensure the most ideal outcomes.

15. END