What is the approach to prognostication and treatment in septic shock?

Approach to Prognostication and Treatment in Septic Shock

Early prognostication and goal-directed treatment are essential in septic shock management, with goals of care discussions recommended within 72 hours of ICU admission to improve mortality and quality of life outcomes. 1

Prognostic Assessment

Key Prognostic Indicators

• Serum lactate levels: Higher levels (≥2 mmol/L) indicate tissue hypoperfusion and correlate with mortality 2
• Vasopressor requirements: Higher norepinephrine doses strongly predict mortality 3
• Venous-to-arterial carbon dioxide difference (P(v-a)CO2): Elevated levels predict clinical worsening 3

Risk Stratification

Based on the most recent evidence, patients can be classified into three prognostic phenotypes 3:

• Safe phenotype: Low norepinephrine requirements, normal/near-normal lactate, normal P(v-a)CO2
• Intermediate phenotype: Moderate vasopressor needs, moderately elevated lactate
• Unsafe phenotype: High norepinephrine requirements, significantly elevated lactate, abnormal P(v-a)CO2

Additional Mortality Risk Factors

• Mechanical ventilation (nearly 5× increased risk) 4
• SAPS II score >60 4
• Chronic alcoholism 4
• Age >65 years 4
• Prothrombin ratio <40% 4
• PaO₂/FiO₂ ratio <150 4

Treatment Algorithm

Initial Resuscitation (First 3 Hours)

1. Fluid resuscitation:

   • Administer 30 mL/kg crystalloid within 3 hours 2
   • Preferably use balanced crystalloids (e.g., lactated Ringer's) rather than normal saline 2
   • For sepsis without shock: Start with 1-2 L bolus completed within 60-90 minutes 2
   • Monitor for fluid overload, especially in patients at risk for pulmonary edema 2

2. Antimicrobial therapy:

   • Obtain at least 2 sets of blood cultures before starting antibiotics 2
   • Administer broad-spectrum antibiotics within 1 hour of recognition for septic shock 2
   • For sepsis without shock, administer within 3 hours of recognition 2

3. Vasopressor initiation:

   • Start if hypotension persists after fluid administration (SBP <90 mmHg or MAP <65 mmHg) 2, 5
   • Norepinephrine is first-line (starting dose: 0.02 μg/kg/min) 2, 5
   • Target MAP of 65 mmHg 2, 5
   • If MAP remains inadequate despite low-moderate dose norepinephrine (0.1-0.2 μg/kg/min), add vasopressin (0.04 units/min) 2

Ongoing Management (Beyond 6 Hours)

1. Hemodynamic monitoring:

   • Reassess volume status and tissue perfusion within 6 hours if:
     • Hypotension persists after fluid administration
     • Initial lactate is ≥4 mmol/L 2
   • Monitor MAP, mental status, capillary refill time, urine output, and lactate clearance 2

2. Source control:

   • Identify the specific anatomic source of infection as rapidly as possible 2
   • Implement source control intervention as soon as medically and logistically practical 2

3. Nutritional support:

   • Suggest early enteral feeding rather than complete fast or IV glucose only 1
   • Either early trophic/hypocaloric or early full enteral feeding is acceptable 1
   • Advance feeds according to patient tolerance 1

4. Supportive care:

   • Provide oxygen therapy targeting SpO₂ 92-96% 2
   • Implement VTE prophylaxis using LMWH or UFH 2
   • Consider prokinetic agents for feeding intolerance 1
   • Consider post-pyloric feeding tubes in patients with feeding intolerance or high aspiration risk 1

Goals of Care and Prognostication

1. Timing of goals of care discussions:

   • Address goals of care as early as feasible, but no later than within 72 hours of ICU admission 1
   • Discuss prognosis with patients and families 1

2. Integration with treatment planning:

   • Incorporate goals of care into treatment and end-of-life care planning 1
   • Utilize palliative care principles where appropriate 1

3. Benefits of early goals of care discussions:

   • Promote communication and understanding between family and treating team 1
   • Improve family satisfaction 1
   • Decrease stress, anxiety, and depression in surviving relatives 1
   • Facilitate end-of-life decision-making 1
   • Shorten ICU length of stay for patients who die in the ICU 1

Interventions to Avoid

• Omega-3 fatty acids as immune supplements (strong recommendation) 1
• IV selenium (strong recommendation) 1
• Arginine supplementation (weak recommendation) 1
• Glutamine supplementation (strong recommendation) 1
• Routine monitoring of gastric residual volumes (weak recommendation) 1

Common Pitfalls in Septic Shock Management

• Delaying antimicrobial therapy beyond 1 hour in septic shock
• Inadequate fluid resuscitation or excessive fluid administration
• Failure to identify and control the source of infection
• Delayed initiation of vasopressors when indicated
• Not reassessing treatment response and adjusting therapy accordingly
• Overlooking goals of care discussions within the first 72 hours
• Failing to recognize and address high-risk prognostic factors

By following this structured approach to prognostication and treatment in septic shock, clinicians can optimize patient outcomes while respecting patient preferences through timely goals of care discussions.