What are the signs, symptoms, and management of sepsis?

Signs and Symptoms of Sepsis

Sepsis is characterized by a systemic inflammatory response to infection with specific diagnostic criteria including fever or hypothermia, tachycardia, tachypnea, altered mental status, and evidence of organ dysfunction. 1

Diagnostic Criteria for Sepsis

General Parameters

• Fever (core temperature >38.3°C) or hypothermia (core temperature <36°C) 1
• Heart rate >90 beats per minute or >2 standard deviations above normal for age 1
• Tachypnea (respiratory rate >20 breaths per minute) 1
• Altered mental status 1, 2
• Significant edema or positive fluid balance (>20 mL/kg over 24h) 1
• Hyperglycemia (plasma glucose >140 mg/dL) in the absence of diabetes 1

Inflammatory Parameters

• Leukocytosis (WBC >12,000/μL) or leukopenia (WBC <4,000/μL) 1
• Normal WBC count with >10% immature forms 1
• Elevated plasma C-reactive protein or procalcitonin (>2 standard deviations above normal) 1, 3

Hemodynamic Parameters

• Arterial hypotension (SBP <90 mmHg, MAP <70 mmHg, or SBP decrease >40 mmHg in adults) 1
• Mixed venous oxygen saturation >70% 1
• Cardiac index >3.5 L/min/m² 1

Organ Dysfunction Parameters

• Arterial hypoxemia (PaO₂/FiO₂ <300) 1
• Acute oliguria (urine output <0.5 mL/kg/h for at least 2h despite adequate fluid resuscitation) 1
• Creatinine increase ≥0.5 mg/dL 1
• Coagulation abnormalities (INR >1.5 or aPTT >60s) 1
• Ileus (absent bowel sounds) 1
• Thrombocytopenia (platelet count <100,000/μL) 1
• Hyperbilirubinemia (plasma total bilirubin >4 mg/dL) 1

Tissue Perfusion Parameters

• Hyperlactatemia (>1 mmol/L) 1
• Decreased capillary refill or skin mottling 1
• Peripheral cyanosis 1

Warning Signs for Severe Sepsis

Certain systemic symptoms strongly predict progression to severe sepsis or septic shock:

• Altered mental status (4.29 times higher risk) 2
• Dyspnea (2.92 times higher risk) 2
• Gastrointestinal symptoms (2.31 times higher risk) 2
• Muscle weakness (2.24 times higher risk) 2

Severe Sepsis and Septic Shock

Severe Sepsis

Defined as sepsis with evidence of organ dysfunction or tissue hypoperfusion 1:

• Sepsis-induced hypotension 1
• Lactate above upper limits of normal 1
• Urine output <0.5 mL/kg/h for >2h despite adequate fluid resuscitation 1
• Acute lung injury with PaO₂/FiO₂ <250 (in absence of pneumonia) or <200 (with pneumonia) 1
• Creatinine >2.0 mg/dL 1
• Bilirubin >2 mg/dL 1
• Platelet count <100,000/μL 1
• Coagulopathy (INR >1.5) 1

Septic Shock

Defined as severe sepsis with persistent hypotension despite adequate fluid resuscitation and evidence of tissue hypoperfusion 1

Management of Sepsis

Initial Resuscitation

• Prompt fluid resuscitation with crystalloid solutions (at least 20 mL/kg initially) 1
• Target a positive response to fluid loading: >10% increase in systolic/mean arterial pressure, >10% reduction in heart rate, and/or improvement in mental status, peripheral perfusion, and urine output 1
• Some patients may require several liters of fluids during the first 24-48 hours 1

Antimicrobial Therapy

• Early administration of appropriate antibiotics is crucial for reducing mortality 1
• Obtain blood cultures before starting antibiotics, but do not delay antimicrobial therapy 4

Source Control

• Identify and control the source of infection promptly 1
• Late or incomplete source control procedures may adversely affect outcomes 1

Vasopressors

• Norepinephrine is the first-line vasopressor for hypotension unresponsive to fluid resuscitation 1
• In resource-limited settings, adrenaline infusions may be an acceptable alternative 1

Monitoring and Support

• Regular assessment of vital signs, mental status, urine output, and peripheral perfusion 1
• Monitor for signs of organ dysfunction and provide appropriate supportive care 4

Special Considerations

Neutropenic Patients

• White blood cell count cannot be used as a criterion to define sepsis in neutropenic patients 1
• Main risk factors include severity and duration of granulocytopenia, disruption of skin and mucosal barriers, and malnutrition 1

Resource-Limited Settings

• Clinical diagnosis supported by basic laboratory tests like complete blood count 1
• Ultrasound can be a cost-effective diagnostic tool when CT is unavailable 1
• Adapt fluid resuscitation protocols based on available monitoring capabilities 1

Early recognition and prompt intervention are critical for improving outcomes in sepsis. The presence of systemic symptoms combined with signs of infection should trigger immediate assessment for sepsis and initiation of appropriate management strategies 2, 4.