Residency · Residency · Emergency Medicine

Sepsis: Recognition, Bundles, and Early Goal-Directed Therapy's Legacy

Introduction

Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. It remains one of the leading causes of mortality in the ED, with an estimated 1.7 million cases annually in the United States. The evolution from SIRS-based definitions to the Sepsis-3 criteria, and the legacy of early goal-directed therapy (EGDT), have profoundly shaped emergency medicine practice. Rapid recognition and protocolized care remain the cornerstones of management.

Definitions: From Sepsis-1 to Sepsis-3

Sepsis-1 (1991) and Sepsis-2 (2001)

The original definitions classified sepsis as SIRS plus suspected infection. SIRS criteria required two or more of the following: temperature above 38.3 or below 36 degrees Celsius, heart rate above 90, respiratory rate above 20 or PaCO2 below 32, and WBC above 12,000, below 4,000, or more than 10 percent bands. Severe sepsis denoted sepsis with organ dysfunction, and septic shock indicated sepsis with refractory hypotension requiring vasopressors. These definitions were criticized because SIRS is overly sensitive and non-specific, being present in many non-infectious conditions.

Sepsis-3 (2016)

The Sepsis-3 definitions reframed sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection, operationally defined as an increase in the SOFA score of 2 or more points. Septic shock was redefined as sepsis with persistent hypotension requiring vasopressors to maintain a mean arterial pressure of 65 mmHg or higher, combined with a lactate above 2 mmol/L despite adequate fluid resuscitation. The quick SOFA (qSOFA) was introduced as a bedside screening tool, incorporating a respiratory rate of 22 or higher, altered mentation (GCS below 15), and a systolic blood pressure of 100 mmHg or lower. Two or more points suggest a higher risk of poor outcomes. However, qSOFA performs poorly as a screening tool in the ED because of its low sensitivity and is better suited as a prognostic indicator than a detection tool.

Early Recognition

Clinical gestalt remains the most sensitive screening tool for sepsis in the emergency department. Serum lactate of 2 mmol/L or higher suggests tissue hypoperfusion, and a lactate of 4 mmol/L or higher is associated with mortality exceeding 25 percent. Vital sign abnormalities including tachycardia, hypotension, tachypnea, and fever or hypothermia (with hypothermia carrying a worse prognosis) are key early indicators. Occult sepsis, in which patients have normal blood pressure but elevated lactate, represents a dangerous subgroup with significant mortality that warrants aggressive resuscitation. Electronic health record-based sepsis alerts, which combine vital signs, laboratory values, and documentation to trigger early identification, are institution-specific but increasingly common.

<image>Flowchart illustrating the progression from infection to sepsis to septic shock using Sepsis-3 criteria, showing SOFA score calculation with organ system components (respiratory, coagulation, liver, cardiovascular, CNS, renal) and the criteria for septic shock including vasopressor requirement and lactate threshold</image>

The Hour-1 Bundle (Surviving Sepsis Campaign 2018/2021)

The Surviving Sepsis Campaign recommends initiating all bundle elements within 1 hour of sepsis recognition. The first element is measuring the lactate level, with remeasurement within 2 to 4 hours if the initial lactate exceeds 2 mmol/L to guide resuscitation. Blood cultures should be obtained before antibiotics, with at least 2 sets (aerobic and anaerobic) drawn from separate sites, though antibiotics should not be delayed if cultures cannot be drawn promptly. Broad-spectrum antibiotics should be administered as quickly as possible, because each hour of delay in antibiotic administration is associated with increased mortality (approximately 4 to 7 percent per hour in septic shock). Rapid IV fluid resuscitation with at least 30 mL/kg of crystalloid should be initiated for patients with hypotension or a lactate of 4 mmol/L or higher. Vasopressors should be started if hypotension persists during or after fluid resuscitation, targeting a mean arterial pressure of 65 mmHg or greater.

Fluid Resuscitation

Crystalloid is the first-line resuscitation fluid, with the choice between normal saline and balanced crystalloids such as lactated Ringer's or Plasmalyte. The SMART trial demonstrated that balanced crystalloids reduce the composite outcome of death, new renal replacement therapy, and persistent renal dysfunction compared to normal saline. The initial bolus is 30 mL/kg within the first 3 hours, with reassessment after each bolus. Fluid responsiveness should be assessed using passive leg raise, point-of-care ultrasound (IVC diameter and collapsibility), pulse pressure variation, or stroke volume variation. Excessive fluid administration should be avoided because fluid overload is independently associated with increased mortality. The transition to vasopressors should occur early if hypotension persists.

Vasopressors and Inotropes

Norepinephrine is the first-line vasopressor in septic shock, providing potent vasoconstriction through alpha-1 agonism with a modest increase in cardiac output through beta-1 agonism. Vasopressin at 0.03 to 0.04 units per minute is added as a second agent to reduce norepinephrine requirements and is not titrated. Epinephrine is a second-line agent when additional inotropic support is needed. Phenylephrine, a pure alpha-1 agonist, is used when tachyarrhythmias limit norepinephrine use. Norepinephrine can be safely administered through a peripheral IV (ideally a large-bore, proximal vein) for the first 2 to 4 hours while central access is being obtained. Corticosteroids, specifically hydrocortisone 200 mg per day (50 mg IV every 6 hours), are recommended in refractory septic shock requiring escalating vasopressor doses. The ADRENAL and APROCCHSS trials provided mixed results but support their use in the sickest patients.

<image>Diagram showing a stepwise vasopressor and inotrope algorithm for septic shock management, starting with norepinephrine as first-line, adding vasopressin as second-line, then considering epinephrine or dobutamine for myocardial dysfunction, with decision points based on MAP and cardiac output assessment</image>

Early Goal-Directed Therapy: Rise and Legacy

Rivers Trial (2001)

The landmark single-center randomized controlled trial by Rivers demonstrated a 16 percent absolute mortality reduction with a protocolized resuscitation bundle targeting CVP 8 to 12, MAP of 65 mmHg or higher, urine output of 0.5 mL/kg per hour or greater, and ScvO2 of 70 percent or higher. Interventions included central venous catheterization, continuous ScvO2 monitoring, blood transfusion to a hematocrit of 30 percent or higher, and dobutamine for low ScvO2.

ProCESS, ARISE, and ProMISe Trials (2014-2015)

Three large multicenter randomized controlled trials found no mortality benefit of protocolized EGDT over usual care. However, "usual care" in these trials had already incorporated many of EGDT's core principles, including early antibiotics, aggressive fluid resuscitation, and lactate monitoring, reflecting how thoroughly the standard of care had improved since the Rivers era. EGDT's lasting legacy is the now-embedded principle that early, aggressive, protocolized sepsis care saves lives.

Source Control

Identifying and controlling the source of infection is essential: abscesses should be drained, infected devices removed, necrotic tissue debrided, and emergent surgical intervention performed when indicated. CT with contrast should be obtained early to identify surgically drainable sources. Delays in source control are associated with increased mortality, particularly in abdominal sepsis.

Antibiotic Selection

Empiric broad-spectrum antibiotic coverage is guided by the suspected source. For pulmonary infections, ceftriaxone plus azithromycin is standard, with piperacillin-tazobactam for healthcare-associated pneumonia. For urinary sources, ceftriaxone or a fluoroquinolone is appropriate, with broader coverage using piperacillin-tazobactam or meropenem for urosepsis. For intra-abdominal infections, piperacillin-tazobactam or meropenem plus metronidazole provides appropriate coverage. For skin and soft tissue infections, vancomycin plus piperacillin-tazobactam covers necrotizing infections. MRSA coverage with vancomycin or linezolid should be considered in patients with risk factors. Antifungal coverage should be considered in immunocompromised patients or those with prolonged ICU stays.

<image>Infographic summarizing the Surviving Sepsis Campaign Hour-1 bundle with five clock icons representing each element: measure lactate, obtain blood cultures, administer broad-spectrum antibiotics, begin 30 mL/kg crystalloid for hypotension or lactate >= 4, and apply vasopressors for persistent hypotension targeting MAP >= 65</image>

Clinical Pearls

Time to antibiotics is the most modifiable variable associated with sepsis mortality, and administration should be targeted within 1 hour of recognition. Lactate clearance, defined as a decrease of 10 to 20 percent or more within 2 to 4 hours, is a useful marker of adequate resuscitation. Balanced crystalloids are preferred over normal saline for large-volume resuscitation. Peripheral vasopressors are safe for initial resuscitation and should not be delayed while awaiting central access. EGDT as a rigid protocol is no longer practiced, but its core principles of early recognition, rapid antibiotics, volume resuscitation, and hemodynamic optimization remain the standard of care.

References

1. Singer M, Deutschman CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801-810.
2. Rivers E, Nguyen B, Havstad S, et al. Early goal-directed therapy in the treatment of severe sepsis and septic shock. N Engl J Med. 2001;345(19):1368-1377.
3. ProCESS Investigators. A randomized trial of protocol-based care for early septic shock. N Engl J Med. 2014;370(18):1683-1693.
4. Evans L, Rhodes A, Alhazzani W, et al. Surviving Sepsis Campaign: international guidelines for management of sepsis and septic shock 2021. Crit Care Med. 2021;49(11):e1063-e1143.

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