title: Acute mortality in critically ill patients undergoing echocardiography with or without an ultrasound contrast agent.
abstract: OBJECTIVE
  The objective of this observational study was to compare 48-h all-cause mortality (as well as hospital stay mortality) among critically ill patients who underwent echocardiography either with or without an ultrasound contrast agent (UCA).
  
  
  BACKGROUND
  The safety of perflutren-based UCAs has been questioned by the U.S. Food and Drug Administration (particularly when administered to critically ill patients) following rare reports of deaths or life-threatening adverse reactions that occurred in close temporal relationship to UCA administration.
  
  
  METHODS
  This was a retrospective observational outcome study conducted in critically ill patients to compare all-cause 48-h and hospital stay mortality subsequent to echocardiography procedures performed either with or without a UCA. The study utilized discharge data from a database maintained by Premier, Inc. (Charlotte, North Carolina). Premier's database is the largest U.S. hospital-based, service-level comparative database for quality and outcomes research, and provides detailed resource utilization data along with patients' primary and secondary diagnoses and procedure billing codes. A propensity score-matching algorithm between UCA-enhanced echocardiography patients and non-contrast-enhanced echocardiography patients was utilized to reduce the potential for imbalance in covariates of selected patients in the comparison of mortality between groups.
  
  
  RESULTS
  Patients undergoing echocardiography with a UCA had lower mortality at 48 h compared with patients undergoing non-contrast-enhanced echocardiography (1.70% vs. 2.50%), with an odds ratio = 0.66 (95% confidence interval [CI]: 0.54 to 0.80). Patients undergoing echocardiography with a UCA had lower hospital stay mortality compared with patients undergoing noncontrast echocardiography (14.85% vs. 15.66%), with an odds ratio = 0.89 (95% CI: 0.84 to 0.96).
  
  
  CONCLUSIONS
  In critically ill, propensity-matched hospitalized patients undergoing echocardiography, use of a UCA is associated with a 28% lower mortality at 48 h in comparison with patients undergoing non-contrast-enhanced echocardiography. These results are reassuring, given previous reports suggesting an association between UCAs and increased mortality in critically ill patients.
authors.affiliation: Saint Luke's Mid America Heart Institute, Kansas City, Missouri. Electronic address: mmain@saint-lukes.org.
authors.forename: Michael L
authors.initials: ML
authors.lastname: Main
authors.affiliation: Lantheus Medical Imaging, Inc., North Billerica, Massachusetts.
authors.forename: Mark G
authors.initials: MG
authors.lastname: Hibberd
authors.affiliation: Premier, Inc., Charlotte, North Carolina.
authors.forename: Amy
authors.initials: A
authors.lastname: Ryan
authors.affiliation: Premier, Inc., Charlotte, North Carolina.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Lowe
authors.affiliation: Lantheus Medical Imaging, Inc., North Billerica, Massachusetts.
authors.forename: Paula
authors.initials: P
authors.lastname: Miller
authors.affiliation: Lantheus Medical Imaging, Inc., North Billerica, Massachusetts.
authors.forename: Gajanan
authors.initials: G
authors.lastname: Bhat
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002423:Cause of Death / Q000639:trends; D003287:Contrast Media; D016638:Critical Illness / Q000401:mortality*; D004452:Echocardiography / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D007902:Length of Stay / Q000639:trends; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011379:Prognosis; D057216:Propensity Score; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology; D055815:Young Adult
chemical_list: D003287:Contrast Media
keywords: APR-DRG; All Patient Refined Diagnosis Related Group; CI; FDA; Food and Drug Administration; ICU; TTE; UCA; cTTE; confidence interval; contrast echocardiography; contrast enhanced ultrasound; contrast-enhanced transthoracic echocardiography; intensive care unit; nTTE; non–contrast-enhanced transthoracic echocardiography; transthoracic echocardiography; ultrasound contrast agent; ultrasound contrast agents