From the Guidelines
Sepsis is diagnosed when a patient has a suspected or confirmed infection along with evidence of organ dysfunction, as defined by the Sequential Organ Failure Assessment (SOFA) score or the quick SOFA (qSOFA) criteria, and patients should meet at least two of the following qSOFA criteria: respiratory rate ≥22 breaths/minute, altered mental status, or systolic blood pressure ≤100 mmHg, as recommended by the 2016 Surviving Sepsis Campaign guidelines 1.
Diagnostic Criteria for Sepsis
The diagnostic criteria for sepsis include:
- Documented or suspected infection plus one or more of the following general variables:
- Fever (>38.3°C)
- Hypothermia (core temperature <36°C)
- Heart rate >90/min or >2 SD above normal value for age
- Tachypnea
- Altered mental status
- Significant edema or positive fluid balance (>20 mL/kg over 24 hrs)
- Hyperglycemia (plasma glucose >140 mg/dL or 7.7 mmol/L) in the absence of diabetes
- Inflammatory variables:
- Leukocytosis (WBC count >12 x103/μL)
- Leukopenia (WBC count <4 x 103/μL)
- Normal WBC count with greater than 10% immature forms
- Plasma C-reactive protein >2 SD above normal value
- Plasma procalcitonin >2 SD above normal value
- Hemodynamic variables:
- Arterial hypotension (SBP <90 mm Hg, MAP <70 mm Hg, or an SBP decrease >40 mm Hg in adults or <2 SD below normal value for age)
- Organ dysfunction variables:
- Arterial hypoxemia (PaO2/FiO2 <300)
- Acute oliguria (urine output <0.5 mL/kg/hr for at least 2 hours despite adequate fluid resuscitation)
- Creatinine increase >0.5 mg/dL or >44.2 μmol/L
- Coagulation abnormalities (INR >1.5 or aPTT >60 s)
- Ileus (absent bowel sounds)
- Thrombocytopenia (platelet count <100 x 103/μL)
- Hyperbilirubinemia (plasma total bilirubin >4 mg/dL or >70 μmol/L)
- Tissue perfusion variables:
- Hyperlactatemia (>1 mmol/L)
- Decreased capillary refill or mottling
Treatment Algorithm for Sepsis
The treatment algorithm for sepsis begins with immediate intervention within the first hour, including obtaining blood cultures, measuring lactate, administering broad-spectrum antibiotics, and providing fluid resuscitation with 30 mL/kg of crystalloids for hypotension or lactate ≥4 mmol/L, as recommended by the 2016 Surviving Sepsis Campaign guidelines 1. The treatment algorithm includes:
- Obtaining blood cultures and measuring lactate
- Administering broad-spectrum antibiotics
- Providing fluid resuscitation with 30 mL/kg of crystalloids for hypotension or lactate ≥4 mmol/L
- Reassessing fluid status and perfusion after initial resuscitation
- Applying vasopressors if the patient remains hypotensive (norepinephrine as first choice at 0.05-0.5 mcg/kg/min)
- Considering adding vasopressin (0.03 units/min) or epinephrine if needed
- Achieving source control as soon as possible by removing infected devices or draining abscesses
- Tailoring antibiotics based on culture results within 48-72 hours
- Considering adding low-dose corticosteroids (hydrocortisone 200 mg/day in divided doses) for patients with persistent hypoperfusion
- Using mechanical ventilation with lung-protective strategies for patients with acute respiratory distress syndrome
- Maintaining blood glucose between 140-180 mg/dL
Antimicrobial Therapy
Antimicrobial therapy should be administered within the first hour of recognition of septic shock or severe sepsis, and the initial empiric anti-infective therapy should cover all likely pathogens, as recommended by the 2016 Surviving Sepsis Campaign guidelines 1. The antimicrobial therapy includes:
- Administering effective IV antimicrobials within the first hour of recognition of septic shock or severe sepsis
- Using empiric broad-spectrum therapy with one or more antimicrobials to cover all likely pathogens
- Reassessing antimicrobial therapy daily for potential de-escalation
- Using low procalcitonin levels or similar biomarkers to assist in the discontinuation of empiric antibiotics
- Considering combination empirical therapy for neutropenic patients or patients with difficult-to-treat, multidrug-resistant bacterial pathogens.
From the Research
Diagnosis of Sepsis
To diagnose sepsis, patients typically need to meet certain criteria, including:
- Suspected or confirmed infection
- Two or more of the following systemic inflammatory response syndrome (SIRS) criteria:
- Body temperature greater than 38°C or less than 36°C
- Heart rate greater than 90 beats per minute
- Respiratory rate greater than 20 breaths per minute or PaCO2 less than 32 mmHg
- White blood cell count greater than 12,000 cells/mm³ or less than 4,000 cells/mm³
- Organ dysfunction, such as:
- Lactate level greater than 2 mmol/L
- Urine output less than 0.5 mL/kg/h for 12 hours
- Mean arterial pressure less than 65 mmHg
- Mental status changes
Treatment Algorithm for Sepsis
The treatment algorithm for sepsis involves the following steps: