What is a sign of early sepsis?

A Sign of Early Sepsis: Respiratory Alkalosis

The correct answer is (c) respiratory alkalosis, which is a characteristic sign of early sepsis. 1

Pathophysiological Basis of Respiratory Alkalosis in Early Sepsis

• In early sepsis, patients often exhibit a respiratory alkalosis due to centrally mediated hyperventilation 1
• This hyperventilation leads to increased respiratory rate (≥20 breaths per minute), which is one of the defining criteria for sepsis 1
• The increased respiratory rate causes excessive elimination of CO2, resulting in decreased PaCO2 levels (≤32 mmHg) and subsequent alkalosis 1

Clinical Manifestations of Early Sepsis

• Tachypnea (respiratory rate ≥20 breaths per minute) is a key early sign of sepsis 1
• Other early manifestations include:
  • Fever (≥38°C) or hypothermia (≤36°C) 1
  • Tachycardia (heart rate ≥90 beats per minute) 1
  • Altered mental status (malaise, apathy, confusion) 1

Progression of Acid-Base Disturbances in Sepsis

• As sepsis progresses, the acid-base status typically evolves:
  • Early stage: Respiratory alkalosis predominates 1
  • Later stages: Metabolic acidosis develops due to tissue hypoperfusion, lactate accumulation, and organ dysfunction 1
  • Advanced sepsis: Combined respiratory and metabolic acidosis may occur as patients develop respiratory muscle fatigue and parenchymal lung disease 1

Why Other Options Are Incorrect

• (a) Metabolic alkalosis: Not typically associated with early sepsis; may occur later due to other factors like diuretic use or vomiting 1
• (b) Metabolic acidosis: Develops in later stages of sepsis as tissue hypoperfusion leads to lactate accumulation 1
• (d) Respiratory acidosis: Occurs in advanced sepsis when patients develop respiratory muscle fatigue or parenchymal lung disease, not in early sepsis 1

Clinical Implications

• Recognition of respiratory alkalosis in a patient with suspected infection should prompt consideration of early sepsis 1
• Early identification allows for timely implementation of evidence-based interventions:
  • Prompt antibiotic administration 1
  • Appropriate fluid resuscitation 1
  • Hemodynamic monitoring 1
• Waiting for confirmatory laboratory tests is discouraged; clinical assessment should guide initial management 1

Monitoring Considerations

• Continuous monitoring of respiratory parameters is essential in septic patients 1
• Pulse oximetry, respiratory rate, and work of breathing should be closely monitored 1
• Arterial blood gas analysis can confirm respiratory alkalosis but should not delay treatment 1