Septic Shock: A Comprehensive Guide for Nurses

Septic shock is a life-threatening condition resulting from severe infection and systemic inflammation, leading to profound circulatory, cellular, and metabolic dysfunction. It is a subset of sepsis characterized by persistent hypotension despite adequate fluid resuscitation and requiring vasopressors, along with evidence of tissue hypoperfusion. Prompt recognition and treatment are crucial to improving survival rates.

Pathophysiology of Septic Shock

Septic shock begins with an infection that triggers an excessive immune response. Key mechanisms include:

• Systemic Inflammatory Response: Release of pro-inflammatory cytokines leads to widespread vasodilation, increased vascular permeability, and hypotension.
• Coagulation Cascade Activation: Formation of microthrombi contributes to tissue hypoperfusion and organ dysfunction.
• Impaired Cellular Metabolism: Inadequate oxygen and nutrient delivery results in anaerobic metabolism, lactic acidosis, and cellular damage.
• Multi-Organ Dysfunction Syndrome (MODS): Prolonged hypoperfusion causes progressive organ failure.

Causes of Septic Shock

1. Infectious Sources:

Bacterial Infections (most common):

• Gram-negative: Escherichia coli, Klebsiella, Pseudomonas.
• Gram-positive: Staphylococcus aureus, Streptococcus species.

Fungal Infections:

• Candida species.

Viral Infections:

• Influenza, SARS-CoV-2, or other viruses.

2. Common Sites of Infection:

• Lungs: Pneumonia.
• Abdomen: Peritonitis, intra-abdominal abscess.
• Urinary Tract: Pyelonephritis, urosepsis.
• Skin: Cellulitis, necrotizing fasciitis.
• Bloodstream: Central line-associated bloodstream infections (CLABSIs).

Clinical Presentation

Symptoms:

• Fever or hypothermia.
• Chills, rigors.
• Fatigue, malaise.
• Confusion or altered mental status.
• Shortness of breath.
• Oliguria (reduced urine output).

Signs:

Early (Warm Phase):

• Warm, flushed skin (due to vasodilation).
• Tachycardia, tachypnea.
• Bounding pulses.
• Hypotension.

Late (Cold Phase):

• Cold, clammy skin (due to hypoperfusion).
• Weak, thready pulses.
• Severe hypotension.
• Cyanosis.

Diagnosis

1. Clinical Criteria:

• Sepsis: Infection + organ dysfunction (Sequential Organ Failure Assessment [SOFA] score ≥2 points).
• Septic Shock:
  • Persistent hypotension requiring vasopressors to maintain mean arterial pressure (MAP) ≥65 mmHg.
  • Serum lactate >2 mmol/L despite adequate fluid resuscitation.

2. Laboratory Tests:

• Complete Blood Count (CBC): Leukocytosis or leukopenia.
• Serum Lactate: Elevated levels (>2 mmol/L) indicate tissue hypoperfusion.
• Blood Cultures: Obtain before initiating antibiotics.
• Procalcitonin: Marker of bacterial infection.
• Coagulation Studies: Prolonged PT/INR, elevated D-dimer (indicating coagulopathy).

3. Imaging:

• Chest X-ray, CT scan, or ultrasound to identify the source of infection.

Management of Septic Shock

Goals of Treatment:

• Identify and treat the source of infection.
• Restore tissue perfusion and oxygen delivery.
• Prevent organ dysfunction.

1. Initial Resuscitation:

• Fluid Therapy: Administer 30 mL/kg of crystalloids (e.g., normal saline, lactated Ringer’s) within the first 3 hours.
• Reassess fluid responsiveness using dynamic measures (e.g., passive leg raise, stroke volume variation).

2. Antimicrobial Therapy:

• Initiate broad-spectrum antibiotics within 1 hour of diagnosis.
• Examples:
  • Piperacillin-tazobactam + vancomycin.
  • Carbapenems for multidrug-resistant organisms.
• De-escalate therapy based on culture results.

3. Hemodynamic Support:

• Vasopressors: Start norepinephrine as the first-line agent if MAP <65 mmHg after fluid resuscitation.
• Add vasopressin or epinephrine if needed.
• Inotropic Support: Use dobutamine for patients with cardiac dysfunction or low cardiac output.

4. Oxygenation and Ventilation:

• Administer oxygen to maintain SpO₂ ≥94%.
• Consider mechanical ventilation for severe respiratory distress or ARDS (acute respiratory distress syndrome).

5. Corticosteroids:

• Use low-dose hydrocortisone (200 mg/day) if hypotension persists despite fluids and vasopressors.

6. Glucose Control:

• Maintain blood glucose levels between 140–180 mg/dL using insulin therapy if necessary.

7. Source Control:

• Drain abscesses, remove infected catheters, or debride infected tissues as appropriate.

Nursing Interventions

1. Monitoring:

• Regularly assess vital signs (MAP, heart rate, respiratory rate, temperature).
• Monitor urine output (goal: ≥0.5 mL/kg/hour).
• Measure lactate levels and assess for improvement.

2. Administer Medications:

• Administer antibiotics, fluids, vasopressors, and other prescribed medications promptly.

3. Prevent Complications:

• Reposition patients to prevent pressure ulcers.
• Maintain strict aseptic techniques to prevent secondary infections.

4. Supportive Care:

• Address psychological needs of the patient and family.
• Provide reassurance and clear communication about the treatment plan.

Complications of Septic Shock

• Multi-Organ Dysfunction Syndrome (MODS): Failure of ≥2 organ systems (e.g., kidneys, lungs, liver).
• Disseminated Intravascular Coagulation (DIC): Widespread clotting and bleeding.
• Acute Respiratory Distress Syndrome (ARDS): Severe hypoxemia requiring mechanical ventilation.
• Death: High mortality rate, especially in delayed treatment.

Prevention

• Infection Control: Hand hygiene and aseptic techniques.
• Timely Removal of Invasive Devices:(e.g., central lines, catheters).
• Vaccinations: Influenza and pneumococcal vaccines to prevent respiratory infections.
• Early Sepsis Screening: Use sepsis protocols in high-risk patients.

Conclusion

Septic shock is a medical emergency requiring prompt diagnosis and aggressive treatment to prevent complications and improve survival. Nurses play a pivotal role in early recognition, rapid intervention, and providing holistic care to critically ill patients. By employing evidence-based practices, nurses can significantly impact outcomes for patients with septic shock.