The purpose of this study is to determine if fluorescence angiography can detect occult shock (hypoperfusion).

Hypoperfusion may be multifactorial, due to hemorrhage, shock or other disease processes resulting in either capillary leak into the interstitium or profound vasodilatation. Currently, diagnosis of hypoperfusion depends on indirect markers of perfusion such as lactate, blood pressure, creatinine, urine output, and mental status. These are all late signs of hypoperfusion as they are precursors to impending system failure. In this study, the focus will be on one of the most common causes of hypoperfusion in the surgical population; sepsis and septic shock.

Inclusion Criteria:

• Sepsis arm inclusion criteria:

• Diagnosis of severe sepsis and septic shock.

• Sepsis is defined as at least two of the following signs and symptoms (SIRS) that are both present and new to the patient and suspicion of new infection:

  • Hyperthermia >38.3°C or Hypothermia <36°C
  • Tachycardia >90 bpm
  • Tachypnea >20 bpm
  • Leukocytosis (>12,000 μL-1) or Leukopenia (<4,000 μL-1) or >10% bands.
  • Hyperglycemia (>120 mg/dl) in the absence of diabetes.
  • Severe sepsis includes SIRS and at least one of the following signs of hypoperfusion or organ dysfunction that is new and not explained by other known etiology of organ dysfunction:
  • Hypotension (<90/60 or MAP <65)
  • Lactate >2
  • Areas of mottled skin or capillary refill >3 seconds
  • Creatinine >2.0 mg/dl
  • Disseminated intravascular coagulation (DIC), Platelet count <100,000
  • Acute renal failure or urine output <0.5 ml/kg/hr for at least 2 hours

• Hepatic dysfunction as evidenced by:

  • Bilirubin >2 or INR >1.5
  • Cardiac dysfunction
  • Acute lung injury or ARDS

• Control arm inclusion criteria:

  • Do not have diagnosis of sepsis, severe sepsis, or septic shock
  • Are not on vasopressors
  • Are normo-thermic

Exclusion Criteria:

• Sepsis arm exclusion criteria:

  • Pregnant
  • Iodide allergy
  • Burns

• Control arm exclusion criteria:

  • Pregnant
  • Iodide allergy
  • Burns
  • Individuals for whom a surrogate decision maker is not available, or is not able to consent to the study.

The study population will consist of patients who are 1) primarily assigned to the Division of General Surgery, Trauma, and Surgical Critical Care and 2) admitted to the surgical intensive care units will be screened for eligibility based on enrollment criteria.