What are the initial steps in a septic workup?

Initial Septic Workup

Begin immediate resuscitation and obtain blood cultures before antibiotics, but do not delay antimicrobials beyond 1 hour of sepsis recognition—treatment is a medical emergency that takes priority over diagnostic procedures. 1

Immediate Actions (Within First Hour)

Obtain Cultures Before Antibiotics (If No Delay)

• Draw at least 2 sets of blood cultures (both aerobic and anaerobic bottles) before starting antimicrobials, with at least one drawn percutaneously and one through each vascular access device if present 1
• Cultures should not delay antibiotic administration beyond 45 minutes to 1 hour 1, 2
• Sample fluid or tissue from the suspected infection site whenever possible without harming the patient 1, 2
• Perform Gram stain and microscopic examination of sampled specimens when applicable 1, 2

Initiate Antimicrobial Therapy

• Administer IV broad-spectrum antimicrobials within 1 hour of recognizing sepsis or septic shock 1, 3, 2
• Use empiric therapy covering all likely pathogens (bacterial, and potentially fungal or viral) based on suspected source and local resistance patterns 1, 3
• Ensure maximum recommended dosages during the initial phase 1

Begin Aggressive Fluid Resuscitation

• Administer at least 30 mL/kg of IV crystalloid fluid within the first 3 hours 1, 3, 2
• Use crystalloids (balanced crystalloids or normal saline) as the fluid of choice; avoid hydroxyethyl starches 3, 4
• Give fluid challenges of 1000 mL of crystalloids over 30 minutes, repeating as long as hemodynamic parameters improve 4

Clinical Assessment and Source Identification

Perform Targeted Physical Examination

• Evaluate vital signs: heart rate, blood pressure, respiratory rate, temperature, oxygen saturation, and urine output 1, 2
• Assess mental status and level of consciousness 1, 2
• Examine for signs of tissue hypoperfusion: capillary refill time, skin mottling, temperature of extremities, peripheral pulses 2
• Conduct systematic head-to-toe examination to identify infection source, focusing on respiratory system (pneumonia), genitourinary tract, gastrointestinal system, and skin/soft tissue 1, 5

Obtain Detailed History

• Document timing and progression of symptoms 1
• Identify potential infection sources and recent exposures 1
• Review recent antibiotic use and risk factors for resistant organisms 1
• Assess for immunocompromising conditions including HIV/AIDS 1

Laboratory and Diagnostic Studies

Essential Laboratory Tests

• Measure serum lactate immediately at time of sepsis recognition 1, 3, 2
• Repeat lactate within 6 hours if initially elevated (≥2 mmol/L) to guide resuscitation 1, 3
• Obtain complete blood count, comprehensive metabolic panel, liver function tests, and coagulation studies 1

Imaging Studies

• Perform imaging promptly to confirm potential infection source (chest X-ray for pneumonia, ultrasound or CT for abdominal sources) 1, 2
• Do not delay antimicrobials while waiting for imaging results 4, 6

Hemodynamic Monitoring and Targets

Initial Resuscitation Goals (First 6 Hours)

• Target mean arterial pressure (MAP) ≥65 mmHg 1, 3, 2
• Maintain urine output ≥0.5 mL/kg/hour 1
• Guide resuscitation to normalize lactate in patients with elevated levels 1, 3

Reassessment Strategy

• Perform frequent clinical reassessment after each fluid bolus 1
• Look for improvement in blood pressure, heart rate reduction, improved mental status, peripheral perfusion, and urine output 1
• Use dynamic variables (pulse pressure variation, stroke volume variation) over static measures like CVP alone when available 1, 4

Vasopressor Initiation

• Start norepinephrine as first-choice vasopressor if hypotension persists despite adequate fluid resuscitation 3, 4, 2
• Place arterial catheter for continuous blood pressure monitoring once vasopressors are initiated 4

Source Control

• Identify anatomic diagnosis requiring emergent source control (abscess drainage, debridement, device removal) as rapidly as possible 3, 2
• Implement required source control intervention as soon as medically and logistically practical 3, 2

Critical Pitfalls to Avoid

• Never delay antibiotics beyond 1 hour while waiting for cultures or imaging—early antibiotic therapy within 1 hour significantly improves survival 1, 4, 5
• Do not use hydroxyethyl starches for volume replacement—they increase acute kidney injury and mortality 3, 4
• Avoid fluid overresuscitation—stop fluids when no improvement occurs or signs of fluid overload develop (pulmonary edema, worsening oxygenation) 1, 4
• Do not rely solely on CVP to guide fluid therapy—use clinical assessment combined with dynamic parameters 4
• Never leave septic patients unattended—ensure continuous observation and frequent reassessment 1