Treatment of a Patient in Shock

Step 1: Recognize Shock Early

• Hypotension (SBP <90 mmHg or MAP <65 mmHg)
• Tachycardia
• Low cardiac output
• Dusky or mottled skin / delayed capillary refill
• Altered mental status
• Decreased urine output (<0.5 mL/kg/hr)
• Elevated serum lactate
• Low central venous O2 saturation (ScvO2)

Important: Compensated shock exists when tissue hypoperfusion persists despite normal BP and HR. Up to 80-85% of trauma patients have inadequate tissue perfusion even with normalized vitals. Always check lactate. - Schwartz's, p. 179

Step 2: Classify the Type of Shock

Step 3: Universal Immediate Actions (All Types)

1. Airway and breathing - Ensure patent airway, provide supplemental oxygen (high-flow), consider intubation if needed; apply PEEP for pulmonary edema
2. Establish IV access - Two large-bore peripheral IVs; use central venous catheter or intraosseous (IO) access if peripheral access fails
3. Monitoring - ECG, pulse oximetry, arterial line for continuous BP, urinary catheter for urine output
4. Draw blood - CBC, metabolic panel, lactate, coagulation studies, type & crossmatch, blood cultures (before antibiotics in sepsis)

Step 4: Type-Specific Treatment

Hypovolemic / Hemorrhagic Shock

• Control bleeding - Operative hemorrhage control takes absolute priority; "attempts to stabilize an actively bleeding patient anywhere but in the operating room are inappropriate" - Schwartz's, p. 179
• Fluid resuscitation - Crystalloid (lactated Ringer's preferred over normal saline) initially; follow with blood products in hemorrhagic shock
• Damage control resuscitation - Use packed RBCs, FFP, and platelets in a 1:1:1 ratio for massive hemorrhage
• Transfuse PRBCs for Hgb <7 g/dL (or higher threshold if hemodynamically unstable)
• REBOA (resuscitative endovascular balloon occlusion of the aorta) may be used in select patients with non-compressible torso hemorrhage
• Permissive hypotension (MAP 50-65 mmHg) may be appropriate before definitive hemorrhage control to avoid diluting clotting factors

Septic Shock

• Within 1 hour: Start broad-spectrum IV antibiotics (do not delay for cultures beyond 45 min)
• Fluid resuscitation: At least 30 mL/kg IV crystalloid in the first 3 hours; balanced solutions (e.g., lactated Ringer's) are preferred over normal saline
• Source control: Identify anatomic source of infection and drain/debride as quickly as possible
• Vasopressors if fluids fail: Start norepinephrine (first-line) at 0.05 mcg/kg/min, titrate to MAP ≥ 65 mmHg
• Second vasopressor: Add vasopressin (0.03-0.04 units/min) or epinephrine to norepinephrine if needed
• Inotrope: Add dobutamine if myocardial dysfunction persists despite adequate MAP
• Transfuse PRBCs for Hgb <7 g/dL
• Corticosteroids (hydrocortisone 200 mg/day) if shock is refractory to adequate fluids and vasopressors
• Rosen's Emergency Medicine, p. 2757-2758; Schwartz's, p. 160

Cardiogenic Shock

• Treat underlying cause (e.g., PCI/thrombolysis for STEMI - note: fibrinolytic therapy alone does not decrease mortality in cardiogenic shock; early revascularization is key)
• Vasopressors: Norepinephrine or inotropes are first-line; epinephrine alone is associated with increased mortality and should be avoided
• Inotropes: Dobutamine to increase cardiac output/contractility
• Oxygen/PEEP for pulmonary edema
• Mechanical support: Intra-aortic balloon pump (IABP) for refractory cardiogenic shock
• Do NOT give large fluid boluses (risk of worsening pulmonary edema)
• Rosen's, p. 1713

Obstructive Shock

• Tension pneumothorax: Immediate needle decompression (2nd intercostal space, midclavicular line), then tube thoracostomy (4th ICS, anterior axillary line). Do NOT wait for imaging.
• Cardiac tamponade: Emergency pericardiocentesis or surgical pericardial decompression (left thoracotomy for arrest)
• Massive PE: Anticoagulation, thrombolysis (systemic or catheter-directed), or embolectomy

Neurogenic Shock

• Volume resuscitation first
• Norepinephrine is a reasonable first-choice vasopressor (increases HR, contractility, and SVR)
• Phenylephrine (pure alpha-agonist) if hypotension is purely due to vasodilation or patient develops tachyarrhythmia
• Maintain MAP to prevent spinal cord ischemia; restoration of normal BP should precede operative vertebral stabilization

Step 5: Monitor Resuscitation Endpoints

• Target lactate clearance - normalize within 12 hours; failure to do so is associated with 4x higher mortality and 3x higher infection rate - Schwartz's, p. 179
• MAP goal: ≥65 mmHg (higher, e.g., 75 mmHg, in previously hypertensive patients)
• Urine output: 0.5-1 mL/kg/hr
• Avoid over-resuscitation - especially in elderly, CHF, or renal impairment patients

Vasopressor Dosing Summary (from Rosen's EM)

Key Principles to Remember

1. Treat the cause - fluid resuscitation alone is insufficient without definitive management of the etiology
2. Balanced resuscitation - avoid both under-resuscitation and fluid overload; use dynamic variables (stroke volume variation) to guide ongoing fluid therapy
3. Reassess constantly - shock states evolve; medication needs can change greatly within the first hours
4. Vasopressors through central line when possible - to avoid limb ischemia from extravasation; but don't delay treatment if central access isn't immediately available (use proximal large-gauge peripheral IV in extremis)
5. Lactate normalization is the target endpoint; normalized vitals alone do not confirm adequate resuscitation

Recent evidence (2025 network meta-analysis [PMID: 40540789]) continues to support balanced crystalloid over normal saline for septic shock resuscitation, consistent with current Surviving Sepsis Campaign guidance.