What are the early signs of sepsis?

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Early Signs of Sepsis

The early signs of sepsis include fever (>38.3°C) or hypothermia (<36°C), heart rate >90 beats per minute, respiratory rate >20 breaths per minute, altered mental status, and signs of infection, with these symptoms indicating the need for urgent medical evaluation. 1

Key Early Signs and Symptoms of Sepsis

Sepsis can be recognized through several categories of early warning signs:

Temperature Abnormalities

  • Fever (core temperature >38.3°C/100.4°F)
  • Hypothermia (core temperature <36°C/96.8°F)
  • Rigors/shivering 1

Cardiovascular Signs

  • Heart rate >90 beats per minute
  • Arterial hypotension (systolic BP <90 mmHg or decrease >40 mmHg)
  • Mottled or discolored skin
  • Decreased capillary refill 1

Respiratory Changes

  • Respiratory rate >20 breaths per minute
  • Rapid breathing or breathlessness
  • Difficulty breathing
  • Arterial hypoxemia (SpO2 ≤90%) 1

Neurological Changes

  • Altered mental status
  • Confusion
  • Slurred speech
  • Dizziness 1

Urological Signs

  • Decreased urine output (<0.5 ml/kg/h)
  • Lack of urination in a day 1

Other Important Signs

  • Severe muscle pain
  • Feeling very unwell or sense of impending doom
  • Nonblanching rash
  • Clammy/sweaty skin 1
  • Gastrointestinal symptoms (nausea, vomiting, diarrhea) 1, 2

Risk Factors and Populations at Higher Risk

Certain populations are at increased risk for developing sepsis:

  • Elderly individuals 3
  • Immunocompromised patients
  • Neutropenic patients (particularly after chemotherapy) 1
  • Patients with indwelling catheters
  • Those with chronic medical conditions

In neutropenic patients, the white blood cell count cannot be used as a criterion to define sepsis, making other signs and symptoms even more important for early recognition 1.

Progression from Early Sepsis to Severe Sepsis

Early sepsis can rapidly progress to severe sepsis, characterized by organ dysfunction:

  • Respiratory dysfunction: SpO2 ≤90%, central cyanosis, signs of respiratory distress 1
  • Renal dysfunction: Acute oliguria (urine output ≤0.5 mL/kg/h) 1
  • Hepatic dysfunction: Jaundice 1
  • Coagulation dysfunction: Petechiae, ecchymoses, bleeding from puncture sites 1
  • Gastrointestinal dysfunction: Ileus (absent bowel sounds) 1

Important Clinical Considerations

Temperature Patterns Matter

Temperature patterns, rather than absolute values, can be predictive of sepsis development. Studies have shown that abnormal body temperature curves were predictive of sepsis in afebrile critically ill patients, with significantly larger temperature deviations in any 24-hour period (1.5°C vs. 1.1°C) compared to non-septic patients 4.

Systemic Symptoms as Warning Signs

Research indicates that certain systemic symptoms significantly predict the presence or development of severe sepsis:

  • Altered mental status (OR = 4.29)
  • Dyspnea (OR = 2.92)
  • Gastrointestinal symptoms (OR = 2.31)
  • Muscle weakness (OR = 2.24) 2

Early Recognition Leads to Better Outcomes

Early identification of septic patients allows for evidence-based interventions that improve survival, including prompt antibiotics and goal-directed resuscitation 5. The time to adequate treatment is directly linked to outcome, making early recognition critically important 2.

Action Steps When Sepsis Is Suspected

  1. Obtain appropriate cultures before starting antibiotics 6
  2. Administer IV antimicrobials within 1 hour of sepsis recognition 6
  3. Begin fluid resuscitation with crystalloids (at least 30 mL/kg in first 3 hours) 6
  4. Monitor response to treatment through vital signs, urine output, and mental status 6

Remember that sepsis cannot occur without an infection. If a person presents with an acute illness associated with any abnormal signs or symptoms as listed above, urgent medical evaluation should be sought 1.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Sepsis.

The American journal of medicine, 2007

Guideline

Sepsis Management

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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