title: Disease heterogeneity and risk stratification in sepsis-related occult hypoperfusion: A retrospective cohort study.
abstract: OBJECTIVE
  Occult hypoperfusion is associated with increased mortality in patients with sepsis. We sought to determine the practice patterns and outcomes of patients with sepsis-related occult hypoperfusion and introduce a potential method for risk stratification.
  
  
  METHODS
  Single-center retrospective study of normotensive patients presenting to an urban tertiary care emergency department with lactate greater than or equal to 4 mmol/L and suspected infection. χ(2) Testing, Spearman, and Wilcoxon coefficients were used to compare binary, parametric, and nonparametric data, respectively. Patients were divided into 4 groups based on lactate clearance (<4 mmol/L) and the presence of respiratory distress while in the emergency department; outcomes were compared using χ(2) test and analysis of variance.
  
  
  RESULTS
  Median initial lactate was 4.7 mmol/L (interquartile range, 4.2-6.4), and 34 (45.2%) of 73 exhibited respiratory distress. Hyperlactatemia resolved in 67.1% (49/73) of patients. Mortality was 23.3% (17/73), and 19.1% (14/73) required vasopressors. In patients with lactate clearance and without respiratory distress (n = 27), mortality was 0%, and none required vasopressors. In patients with persistent hyperlactatemia and/or respiratory distress (n = 46), 30.4% required vasopressors, and the mortality was 37.0% (P < .01 and P < .01, respectively).
  
  
  CONCLUSIONS
  Patients defined as having occult hypoperfusion comprise a heterogeneous group with a varied degree of illness severity. Identifying those with low risk of clinical deterioration may be important for titration of care.
authors.affiliation: Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA.
authors.forename: Sharukh
authors.initials: S
authors.lastname: Lokhandwala
authors.affiliation: Department of Medicine, Division of Pulmonary and Critical Care, Beth Israel Deaconess Medical Center, Boston, MA.
authors.forename: Ari
authors.initials: A
authors.lastname: Moskowitz
authors.affiliation: Department of Emergency Medicine, Northern Westchester Hospital, Mt Kisco, NY.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Lawniczak
authors.affiliation: Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, MA.
authors.forename: Tyler
authors.initials: T
authors.lastname: Giberson
authors.affiliation: Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, MA; Department of Anesthesia Critical Care, Division of Critical Care, Beth Israel Deaconess Medical Center, Milton, MA.
authors.forename: Michael N
authors.initials: MN
authors.lastname: Cocchi
authors.affiliation: Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, MA; Department of Medicine, Division of Pulmonary and Critical Care, Beth Israel Deaconess Medical Center, Boston, MA. Electronic address: mdonnino@bidmc.harvard.edu.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Donnino
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D004636:Emergency Service, Hospital; D005260:Female; D005440:Fluid Therapy; D006801:Humans; D065906:Hyperlactatemia / Q000097:blood* / Q000150:complications; D007022:Hypotension / Q000150:complications / Q000628:therapy; D019344:Lactic Acid / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012306:Risk; D018570:Risk Assessment; D018805:Sepsis / Q000097:blood* / Q000150:complications / Q000401:mortality / Q000628:therapy; D014662:Vasoconstrictor Agents / Q000627:therapeutic use
chemical_list: D014662:Vasoconstrictor Agents; D019344:Lactic Acid
keywords: Lactate clearance; Mortality; Occult hypoperfusion; Sepsis; Vasopressor