Rosen & Barkin's 5-Minute Emergency Medicine Consult (647 page)

DIAGNOSIS

Generalized shock:

• Hypotension
  
• Decreased peripheral pulses
  
• Tachycardia
  
• Tachypnea
  
• Decreased urine output
  
• Diaphoresis
  
• Obtundation
  
• Lethargy
  

Standard medical history with a goal of deducing the etiology of the shock and important precipitating factors

• Standard physical exam to assist in determining the etiology (e.g., wounds, cardiac exam signs of cellulitis and urticarial rash, etc.)
  
• Targeted physical exam to focus on the type of shock state:
  
  • Hypovolemic (classic symptoms):
    
    • Neck veins are flat.
      
    • Mucous membranes are dry.
      
    • Extremities are cold.
      
  • Cardiogenic shock (classic symptoms):
    
    • Jugular venous distension is present.
      
    • Mucous membranes are moist.
      
    • Extremities are cold.
      
  • Early septic shock (classic symptoms):
    
    • Neck veins are flat.
      
    • Mucous membranes are dry.
      
    • Extremities are warm.
      
    • During late shock, extremities may become cold and mottled.
      

• Identify type or types of shock present.
  
• Identify underlying cause of shock.
  

• Hemoglobin/hematocrit
  
• WBC:
  
  • High: Nonspecific marker of infection
    
  • Low: Neutropenic infections
    
• Electrolytes
  
• Blood glucose:
  
  • High: Diabetic ketoacidosis or septic shock
    
  • Low: Pediatric sepsis
    
• Prothrombin time/partial thromboplastin time
  
• Cardiac enzymes
  
• Urinalysis
  
• β-human chorionic gonadotropin
  
• Lactic acid level:
  
  • Good surrogate marker of shock state
    

• CXR
  
• ECG
  
• Abdominal US
  
• CT abdomen:
  
  • Requires that the patient 1st be stabilized
    
  • In the setting of abdominal trauma and in search for suspicion of abdominal infection
    

EKG:

• Assess for ischemia and other disorders of cardiac muscle:
  
• Electrical alternans or low voltage with cardiac tamponade
  
• Right-heart strain with pulmonary embolism
  

TREATMENT

• ABCs per standard protocol
  
• Fluid resuscitation as warranted
  

• Large-bore IV access:
  
  • When possible, central venous access and monitoring
    
• Fluid resuscitation in noncardiogenic shock patients
  
• Control bleeding with direct pressure measures.
  
• Stabilization of a fractured pelvis with sheet or commercial device or external fixation
  

• Hypovolemic shock:
  
  • Identify source of volume depletion
    
  • Aggressive fluid resuscitation keeping systolic blood pressure (SBP) >100 mm Hg until definitive treatment
    
  • 2–3 L crystalloid initially
    
  • Packed RBCs if 2–3 L crystalloids do not improve SBP
    
  • Identify source of bleeding and rapidly move toward definitive treatment.
    
  • Thoracotomy and aortic cross-clamping in refractory shock with penetrating torso trauma
    
• Cardiogenic shock:
  
  • Ease work of breathing with intubation
    
  • Insult-specific therapy (e.g., thrombolytics for MI, pericardiocentesis for pericardial tamponade)
    
  • Treat dysrhythmias.
    
  • Vasopressors (norepinephrine or dopamine) as needed
    
• Septic shock:
  
  • Aggressive crystalloid fluid resuscitation
    
  • Titrate fluid to urine output >30 cc/hr
    
  • Blood product transfusion to maintain HCT 30–35%
    
  • Early antimicrobial therapy
    
  • Inotropic support as needed
    
  • Norepinephrine as preferred 1st-line infusion
    
• Anaphylactic shock:
  
  • Intubation for airway compromise
    
  • Epinephrine
    
  • Subcutaneous in noncritical settings
    
  • IV drip for immediate life threats or refractory hypotension
    
  • H1 blockers (diphenhydramine)
    
  • H2 blockers (cimetidine)
    
  • Corticosteroids (hydrocortisone or methylprednisolone)
    
  • Nebulized β2-antagonists for bronchospasm
    
  • Patients taking β-blockers may be more likely to experience severe symptoms of anaphylaxis
    
• Pharmacologic shock:
  
  • Decontamination of overdoses with charcoal
    
  • Inotropic agents as needed
    
  • Drug-specific antidotes
    
• Neurogenic shock:
  
  • Supportive therapy
    
  • Traction and fracture stabilization
    
  • Corticosteroids
    

• Albuterol: 2.5 mg/2.5 cc nebulizer PRN
  
• Calcium gluconate: 100–1,000 mg IV at 0.5–2 mL/min
  
• Cimetidine: 300 mg IV
  
• Diphenhydramine: 50–100 mg IV over 3 min
  
• Dobutamine: 5–40 μg/kg/min IV:
  
  • Dopaminergic: 1–3 μg/kg/min IV
    
  • β-effects: 3–10 μg/kg/min IV
    
  • α/β-effects: 10–20 μg/kg/min IV
    
  • α-effects: 20 μg/kg/min IV
    
• Epinephrine:
  
  • 1–4 μg/min IV infusion
    
  • Endotracheal 1 mg (10 mL of 1:10,000) once followed by 5 quick insufflations
    
  • Place 1 mg in 250 mL D
    ₅
    W = 4 μg/mL
    
• Glucagon: 1–5 mg IV bolus initial, then 1–20 mg/h infusion
  
• Hydrocortisone: 5–10 mg/kg IV
  
• Methylprednisolone: 1–2 mg/kg IV
  
• Naloxone: 0.01 mg/kg IV initial, titrate to effect
  
• Norepinephrine: Start 2–4 μg/min IV, titrate up to 1–2 μg/kg/min IV
  
• Phenylephrine: 40–180 μg/min IV
  

FOLLOW-UP

• All patients in shock need to be admitted.
  
• ICU criteria:
  
  • All patients with persistent shock need ICU monitoring.
    
• Patients with shock definitively reversed may be admitted to non-ICU setting (e.g., tension pneumothorax that has been decompressed and chest tube placed).
  

Patients who are in shock should not be discharged home from the ED.

• Traumatic hypovolemic shock (hemorrhagic shock) patients may require a trauma center.
  
• Patients with cardiogenic shock due to MI may require cardiac catheterization or additional cardiac surgery support.
  
• Septic shock due to necrotizing fasciitis may require advanced surgical support.
  
• Neurogenic shock with spinal cord injury will require neurosurgical care.
  

• Identify the etiology of shock.
  
• Aggressively resuscitate the patient, 1st with IV fluids and next with vasopressor support to minimize hypoxic exposure.
  

• Havel C, Arrich J, Losert H, et al. Vasopressors for hypotensive shock.
  Cochrane Database Syst Rev.
  2011;(5):CD003709.
  
• Puskarich MA. Emergency management of severe sepsis and septic shock.
  Curr Opin Crit Care
  . 2012;18(4):295–300.
  
• Strehlow MC. Early identification of shock in critically ill patients.
  Emerg Med Clin North Am
  . 2010;28(1):57–66, vii.
  

CODES

• 785.50 Shock, unspecified
  
• 785.51 Cardiogenic shock
  
• 785.59 Other shock without mention of trauma
  

BASICS