Resuscitation and Shock LSU Medical Student Clerkship, New Orleans, LA

Resuscitation Goals Provide an introduction to the ABC’s of resuscitation in the ED Review available oxygen delivery devices and airway adjuncts Describe the pathophysiology of shock and its major subtypes Provide an introduction to the basics of treatment of shock in the ED

Resuscitation Shock Shock is defined as circulatory insufficiency that creates an imbalance between tissue oxygen supply and oxygen demand. The result of shock is global tissue hypoperfusion and is associated with a decreased venous oxygen content and metabolic acidosis (lactic acidosis).

Resuscitation Pathophysiology of Shock Imbalance between tissue supply and demand  Anaerobic Metabolism  Lactic Acid Production

Resuscitation Emergency Medicine Always Starts with the ABC’s Compressions A – Airway B - Breathing C - Circulation

Resuscitation Airway Remove any obstructions Head tilt, chin lift Jaw Thrust Oropharyngeal and nasopharyngeal airways Orotracheal and nasotracheal intubation Cricothyroidotomy and Tracheotomy

Resuscitation Jaw Thrust

Resuscitation Head Tilt

Resuscitation Nasopharygeal airway

Resuscitation Orotracheal airway

Resuscitation Supraglottic devices

Resuscitation Orotracheal

Resuscitation Neck airways

Resuscitation challenges…

Resuscitation Rapid Sequence Intubation Assume every ED patient has a full stomach Combination of sedation and paralysis to facilitate procedure Evidence based to increase chance of success and decrease incidence of aspiration Not without its dangers: paralyzing a patient who cannot be ventilated

Resuscitation Rapid Sequence Intubation Assume every ED patient has a full stomach Combination of sedation and paralysis to facilitate procedure Evidence based to increase chance of success and decrease incidence of aspiration Not without its dangers: paralyzing a patient who cannot be ventilated

Resuscitation RSI Indications Airway Protection Respiratory Failure Expected Clinical Course

Resuscitation Breathing Hypoxic Respiratory Failure Hypercapnic Respiratory Failure Mechanical Respiratory Failure

Resuscitation Oxygen Delivery Devices Nasal Cannula - up to 40% FiO2 Venturi mask - fixed 25% to 50% FiO2 Nonrebreather mask - theoretical 100% FiO2 Bag Valve Mask – 100%FiO2 Noninvasive Positive Pressure Ventilation (BiPAP or CPAP) FiO2 up to 100% based on setting

Resuscitation Nasal cannula/ Venturi mask

Resuscitation

Positive pressure ventilation

Resuscitation Circulation Restoration of a pulse is the first goal ACLS However having a pulse is not the end of the story Adequate circulation requires correction of original mismatch

Resuscitation Types of Shock Hypovolemic Cardiogenic Distributive Obstructive

Resuscitation Hypovolemic Shock Caused by inadequate circulating volume (decreased preload) Hemorrhage (trauma, ruptured AAA, GI bleeding) Fluid loss (diarrhea, vomiting, poor intake, burns, third spacing)

Resuscitation Cardiogenic Shock Caused by pump failure (decreased cardiac output) Myopathic – systolic dysfunction, diastolic dysfunction Dysrrythmic – disorganized cardiac activity

Resuscitation Distributive Shock Caused by maldistribution of bloodflow from peripheral vasodilatation and decrease in SVR (decreased afterload) Sepsis Neurogenic Anaphylaxis Toxic shock syndrome

Resuscitation Obstructive shock Caused by extracardiac obstruction to blood flow Cardiac tamponade, tension pneumothorax, pulmonary embolus

Resuscitation Clinical Presentation of Shock Clinical presentation varies with type of shock History and physical are key for determining underlying cause Hypotension is very common Altered mental status may be most sensitive sign of illness Lethargy, cool clammy skin, tachypnea, tachycardia, and cyanosis are common as well DIAGNOSE THE UNDERLYING CAUSE!!!!

Resuscitation Treating Shock Early intervention is vital to reducing morbidity and mortality All efforts are aimed at balancing maximizing tissue oxygen supply decreasing tissue oxygen demand

Resuscitation Systemic inflammatory response syndrome Early phase 1) temperature greater than 38°C (100.4°F) or less than 36°C (96.8°F); (2) heart rate faster than 90 beats/min; (3) respiratory rate faster than 20 breaths/min; (4) white blood cell count greater than 12.0 less than 4.0, or with greater than 10 percent bands

Resuscitation Multi organ disease myocardial depression adult respiratory distress syndrome, disseminated intravascular coagulation, hepatic failure renal failure.

Resuscitation Early Goal Directed Shock Therapy

Resuscitation Treating Shock - Breathing Maximize oxygenation (Keep Sa02 > 93%) Control the work of breathing. Respiratory muscles are highly metabolic and can greatly increase oxygen demand.

Resuscitation Treating Shock – Fluid Resuscitation Most patients in shock have either an absolute or relative volume deficit, except the patient in cardiogenic shock with pulmonary edema Central venous catheterization can guide help guide via central venous pressure monitoring and SVCO2 monitoring A good bolus is a bold bolus!! Massive trauma transfusion- more blood products/ crystalloids

Resuscitation Treating Shock – Vasopressors Vasopressor agents are used when there has been an inadequate response to volume resuscitation or when a patient has contraindications to volume infusion Vasopressors are most effective after fluid resuscitation but may be necessary to avoid prolonged hypotension Goal is generally a MAP of 65

Resuscitation Treating Shock – Vasopressors

Resuscitation Treating Shock – Endpoints No therapeutic end point is universally effective, and only a few have been tested in prospective trials, with mixed results.

Resuscitation Treating Shock – Endpoints

Resuscitation Take Home Points The goal of resuscitation is to maximize survival and minimize morbidity using objective hemodynamic and physiologic values to guide therapy. The first few hours are vital. Diagnose and treat the underlying cause!!! Stay ahead of shock!!!!!!!