What is the initial treatment for shock?

Initial Treatment of Shock

Begin immediate fluid resuscitation with isotonic crystalloid boluses (20 mL/kg in adults, 10-20 mL/kg in children) while simultaneously establishing vascular access, administering high-flow oxygen, and preparing vasopressor therapy with norepinephrine as the first-line agent if hypotension persists despite adequate fluid loading. 1, 2

Immediate Stabilization (First 5-15 Minutes)

Airway, Breathing, and Circulation

• Initiate high-flow oxygen therapy immediately to achieve oxygen saturation >90-95%, regardless of shock etiology 2, 1
• Establish vascular access rapidly using IV or intraosseous (IO) routes if IV access is difficult 2, 1
• Monitor vital signs continuously including heart rate, blood pressure, temperature, pulse oximetry, ECG, and urine output 2, 1
• Consider early intubation if increased work of breathing, inadequate respiratory effort, or marked hypoxemia is present, but administer volume loading before intubation as positive pressure ventilation reduces preload 2

Aggressive Fluid Resuscitation

• Administer isotonic crystalloid boluses of 20 mL/kg (adults and older children) or 10 mL/kg (neonates) as rapid push boluses 2, 1
• Reassess perfusion after each bolus and continue fluid administration until perfusion improves or signs of fluid overload develop 2, 1
• Up to 60 mL/kg may be required in the first hour, particularly in distributive shock states 2, 1
• Use either balanced crystalloids or normal saline as the fluid of choice; both are acceptable 2
• Stop fluid boluses if hepatomegaly or increased work of breathing (rales) develops, indicating fluid overload 2

The Surviving Sepsis Campaign guidelines emphasize that crystalloids are strongly recommended over colloids for initial resuscitation, and hydroxyethyl starches should never be used due to increased mortality and acute kidney injury risk 2, 3.

Hemodynamic Support (15-60 Minutes)

Vasopressor Therapy for Fluid-Refractory Shock

• Initiate norepinephrine as the first-choice vasopressor when hypotension persists despite adequate fluid resuscitation 2, 1, 3
• Target mean arterial pressure (MAP) of 65 mmHg as the initial goal 2, 1, 3
• Place an arterial catheter as soon as practical for continuous blood pressure monitoring in all patients requiring vasopressors 2, 1

The 2017 Surviving Sepsis Campaign guidelines provide strong evidence (moderate quality) that norepinephrine is superior to dopamine as first-line therapy, with dopamine reserved only for highly selected patients with low risk of tachyarrhythmias and absolute or relative bradycardia 2.

Alternative and Adjunctive Vasopressors

• Add vasopressin (0.03 units/min) or epinephrine if additional agents are needed to achieve MAP targets or to reduce norepinephrine dosage 2
• Consider epinephrine (0.05-0.3 mcg/kg/min) as an alternative in pediatric patients or when combined inotropic/vasopressor effects are needed 2
• Avoid phenylephrine except in specific circumstances: serious arrhythmias with norepinephrine, known high cardiac output with persistent hypotension, or as salvage therapy 2
• Do not use low-dose dopamine for renal protection—this practice is ineffective and strongly discouraged 2, 3

Inotropic Support

• Add dobutamine (up to 20 mcg/kg/min) if evidence of persistent hypoperfusion exists despite adequate fluid loading and vasopressor use, particularly when cardiac output is suspected to be low 2
• In neonates, consider a combination of low-dose dopamine (<8 mcg/kg/min) plus dobutamine (up to 10 mcg/kg/min) as initial therapy 2

Therapeutic Endpoints and Monitoring

Clinical Perfusion Parameters

Target the following endpoints to guide resuscitation 2, 1:

• Capillary refill ≤2 seconds
• Normal pulses with no differential between peripheral and central pulses
• Warm extremities
• Urine output >1 mL/kg/hr (>0.5 mL/kg/hr in adults)
• Normal mental status
• Normal blood pressure for age
• Arterial oxygen saturation >95%

Laboratory and Hemodynamic Targets

• Measure serum lactate at presentation and repeat within 6 hours if initially elevated 1, 4
• Target central venous oxygen saturation (ScvO2) >70% when central venous access is available 2
• Aim for cardiac index >3.3 L/min/m2 when cardiac output monitoring is available 2
• Use dynamic measures of fluid responsiveness (pulse pressure variation, stroke volume variation) rather than static measures like CVP alone when available 3

Type-Specific Considerations

Distributive (Septic) Shock

• Administer broad-spectrum IV antibiotics within 1 hour of recognizing septic shock 1, 4, 3
• Obtain blood cultures before antibiotics if this does not delay therapy beyond 45 minutes 4
• Identify and control the source of infection as rapidly as possible through drainage, debridement, or device removal 4

Hypovolemic Shock

• Control the source of bleeding as the primary intervention in hemorrhagic shock 5
• Consider blood product transfusion when hemoglobin is low and ongoing bleeding is present 2

Cardiogenic Shock

• Prioritize inotropic support (dobutamine) over pure vasopressors when cardiac output is known to be low 2, 6
• Perform urgent echocardiography to identify the cause and guide mechanical circulatory support decisions 6

Obstructive Shock

• Identify and treat reversible causes immediately: tension pneumothorax, pericardial tamponade, or massive pulmonary embolism 1

Critical Pitfalls to Avoid

• Never delay fluid resuscitation while waiting for laboratory results, imaging studies, or central venous access 1, 3
• Never delay antibiotics in suspected septic shock—administer within 1 hour even if cultures are not yet obtained 4, 3
• Do not use hydroxyethyl starches for volume replacement due to increased mortality and acute kidney injury 2, 3
• Avoid fluid overresuscitation in patients with signs of volume overload (hepatomegaly, rales, elevated work of breathing), particularly in dialysis-dependent patients who cannot excrete excess volume 2, 3
• Do not rely solely on CVP to guide fluid resuscitation; use clinical assessment and dynamic parameters 3
• Avoid low-dose dopamine for renal protection—it provides no benefit 2, 3
• Do not withhold life-sustaining therapy in pregnant women with shock; hypotension poses greater risk to mother and fetus than treatment 7

Ongoing Reassessment

• Reassess frequently after each intervention to determine response and guide ongoing management 1, 4
• Continue the fluid challenge technique as long as hemodynamic parameters improve with each bolus 2, 1
• Escalate to higher levels of care and consider mechanical circulatory support or extracorporeal membrane oxygenation (ECMO) if shock remains refractory to medical management 2