What is the immediate course of action and diagnostic testing for a patient admitted with suspected acute sepsis?

Immediate Management of Acute Sepsis in Hospitalized Patients

For patients admitted with suspected acute sepsis, immediately stabilize airway, breathing, and circulation while simultaneously obtaining blood cultures and initiating broad-spectrum intravenous antibiotics within one hour of recognition, followed by aggressive fluid resuscitation with crystalloids.

Initial Assessment and Risk Stratification (First 15 Minutes)

Vital Signs and Severity Scoring

• Calculate a NEWS2 (National Early Warning Score) immediately upon hospital arrival 1
• Document Glasgow Coma Scale (GCS) for both prognostic value and monitoring deterioration 1
• High risk criteria: NEWS2 score ≥7 requires urgent assessment by a team with critical care competencies 1
• Moderate risk: NEWS2 score 5-6 or score of 3 in any single physiological parameter requires urgent clinician review 1
• Consider qSOFA or SOFA scores to determine risk of severe illness or death from sepsis 2

Critical Decision Points Within First Hour

• Senior clinician review and ICU admission decision must occur within the first hour 1
• Do not be falsely reassured by lower early warning scores—septic patients can deteriorate rapidly 1

Diagnostic Testing Protocol (Within First Hour)

Mandatory Immediate Tests

• Blood cultures: Obtain two sets as soon as possible and always within 1 hour of hospital arrival, before antibiotics if this causes no delay >45 minutes 1, 2, 3
• Lactate level: Essential for assessing tissue hypoperfusion and monitoring resuscitation endpoints (target <2 mmol/L) 1
• Complete blood count with differential 3
• Comprehensive metabolic panel including renal and liver function 2
• Coagulation studies (PT/INR, PTT, platelet count) to assess for sepsis-induced coagulopathy 3

Additional Diagnostic Studies

• Procalcitonin (PCT): Rises within 4 hours of bacterial exposure with levels ≥1.5 ng/ml showing 100% sensitivity and 72% specificity for sepsis in ICU populations 3
• C-Reactive Protein (CRP): Levels ≥50 mg/L demonstrate 98.5% sensitivity and 75% specificity for probable or definite sepsis 3
• Site-specific cultures: Urine, sputum, wound cultures, or other relevant specimens based on suspected source 2, 4
• Imaging studies: Chest X-ray, urinary tract imaging, or other studies to identify infection source and complications 2

Antibiotic Administration Protocol

Timing Based on Risk Stratification

• High risk (NEWS2 ≥7 or septic shock): Administer IV antibiotics within 1 hour of recognition 1, 2, 3, 4, 5, 6
• Moderate risk (NEWS2 5-6): Administer within 3 hours 1
• Low risk (NEWS2 <5): Administer within 6 hours 1

Critical caveat: Every 30-minute delay in antibiotic administration for septic shock significantly increases mortality—do not delay beyond one hour for high-risk patients 2, 5

Empiric Antibiotic Selection

• Use broad-spectrum agents active against all likely bacterial and fungal pathogens with good penetration to the presumed infection source 4, 5, 6, 7
• For urosepsis: Amoxicillin plus aminoglycoside, second-generation cephalosporin plus aminoglycoside, or IV third-generation cephalosporin 2
• Avoid fluoroquinolones if local resistance rates ≥10% or patient used them in last 6 months 2
• Consider combination therapy for Pseudomonas infections and neutropenic patients 4, 6
• Implement loading doses for all patients, then individualize subsequent dosing based on pharmacokinetics/pharmacodynamics and organ dysfunction 5

Fluid Resuscitation and Hemodynamic Management

Initial Fluid Bolus

• Administer 500 ml crystalloid bolus rapidly (over 5-10 minutes) for patients with signs of shock or severe sepsis 1
• Give at least 30 ml/kg IV crystalloid within first 3 hours for sepsis-induced hypoperfusion 2, 3
• Monitor carefully for fluid overload with repeated clinical assessment 1

Resuscitation Endpoints

Target the following parameters 1:

• Mean arterial pressure ≥65 mmHg 2, 3
• Capillary refill time <2 seconds 1
• Warm extremities with normal pulses (no differential between peripheral and central) 1
• Urine output >0.5 ml/kg/hour (requires urinary catheter) 1, 2
• Normal mental status 1
• Central venous pressure 8-12 mmHg 1
• Lactate <2 mmol/L 1

Vasopressor Support

• Initiate vasopressors in critical care setting if shock does not respond to initial fluid challenges 1
• Target mean arterial pressure of at least 65 mmHg 2, 3

Source Control

Urgent Interventions

• Identify anatomic source of infection requiring source control as rapidly as possible 2, 3
• Address urinary tract obstruction or anatomical abnormality within 12 hours of diagnosis 2, 3
• Remove or replace indwelling urinary catheters before starting antimicrobials 2
• Use the least invasive approach for source control 2

Ongoing Monitoring and Re-evaluation

Frequency of Reassessment

• High risk patients: Re-calculate NEWS2 and re-evaluate every 30 minutes 1
• Moderate risk patients: Re-evaluate every hour 1
• Low risk patients: Re-evaluate every 4-6 hours 1

Daily Antimicrobial Stewardship

• Reassess antimicrobial therapy daily for potential de-escalation based on culture results and clinical response 2, 4, 5, 6, 7
• De-escalate to narrower spectrum antibiotics within 1 hour of receiving microbiological results 1
• Discontinue combination therapy after 3-5 days once susceptibilities available 4, 6
• Typical duration is 7-10 days; consider shorter courses (5-7 days) with rapid clinical resolution and effective source control 2, 4, 6
• Stop antibiotics if infection is not the etiologic factor for shock 4, 6

Common Pitfalls to Avoid

• Never delay antibiotics beyond one hour for high-risk patients or those with septic shock—mortality increases significantly with each delay 2, 5
• Do not skip blood cultures before antibiotics unless this causes substantial delay (>45 minutes) 2, 3
• Avoid inadequate source control, particularly in obstructive uropathy or abscess formation 2
• Do not use empiric fluoroquinolones in areas with high resistance rates or recent patient exposure 2
• Never give false reassurance from low early warning scores—septic patients deteriorate rapidly and require frequent reassessment 1
• Avoid fluid overload by giving crystalloids in 500 ml boluses with careful monitoring rather than large single volumes 1