SUMMARY

• SAE is a key manifestation of sepsis occurring in up to 70% of ICU patients
• Associated with higher ICU and hospital mortality and long term consequences
• Difficult to assess, diagnose without specific treatment

BACKGROUND

• SAE is probably the most common type of encephalopathy in the ICU
• SAE may occur 36-48 hours BEFORE other systemic symptoms of sepsis.
  • Therefore, should look for sepsis in any patient who develops changes in behavior or consciousness.
• Incidence approximated between 40-50% in sepsis patients
  • Ranges reported between 8-70%
  • Especially in patients with bacteremia
• No consistent definition of SAE
  • Defined by a combination of extracranial infection with clinical signs of neurological dysfunction
• Clinical Manifestations range from impairment of awareness to delirium and coma.
• SAE is a diagnosis of exclusion
• Mental status changes may occur 36-48 hours before other systemic symptoms of sepsis
  • Assess for sepsis in any patient with changes in behavior or consciousness

PATHOPHYSIOLOGY

• Molecular mechanisms leading to SAE not completely known.
  • SAE probably multifactorial (Figure)

• Sub-divided into acute (Delirium) and chronic (Dementia) Phases
  • Acute phase changes in patient consciousness
    • Agitation, hallucinations, decreased concentration, coma.
    • Delirium correlates with development of long term cognitive dysfunction
• Chronic phase dementia
  • No exact risk factors identified contributing to poor neurocognitive outcome
  • At discharge, between 45-62% of sepsis survivors have symptoms of long term cognitive dysfunction

DIAGNOSIS

• SAE is a diagnosis of exclusion
• Mental status changes in sepsis patients may be related to other causes than infection which should be assessed (i.e. electrolytes, vitamin deficiency, etc)
• Ensure primary cerebral pathologies are excluded
• Non-specific Findings:
  • Cerebrospinal fluid
  • Cerebral imaging (CT, MRI)
  • Blood chemistries (CBC, electrolytes)
• Electroencephalograph (EEG)
  • Abnormalities documented in 50% of sepsis patients
  • Aids in assessing severity of SAE
  • Non-convulsive seizures seen in up to 20% of cases
  • EEG Grades & SAE

• • Lack of strong correlation between clinical manifestations and EEG findings
• Screening: CAM-ICU or ICDSC is of great importance but infrequently used
• Risk Factors for SAE:
  • Relationship between SAE & risk factors poorly related
  • Possibilities include: Age; previous cognitive impairment; kidney or Liver failure; sepsis severity

TREATMENT APPROACH

• Patients with SAE have reported mortality rates up to 49% and greater than non-SAE sepsis patients (29%)
  • The cause of the increased mortality is not knownNo specific treatment available
• Treat underlying sepsis
• There is a lack of evidence supporting treatment options are effective on SAE delirium
• Consider non-pharmacologic approaches: sleep; early mobilization; re-orientation, etc.

CONCLUSIONS

• Exact incidence, prevalence and mortality of SAE is unknown due to a lack of SAE definitive criteria.
• Probably the most common type of encephalopathy in the ICU
• SAE is a diagnosis of exclusion

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Erkan Hassan is the Co-Founder & Chief Clinical Officer of Sepsis Program Optimization where he designs & oversees the implementation of solutions to optimize sepsis programs.

To discuss your organization’s Barriers of Effective Sepsis Care, contact Erkan by phone (844) 4SEPSIS (844-473-7747), email (erkan@spo.icu), or video chat.