title: Flat inferior vena cava: indicator of poor prognosis in trauma and acute care surgery patients.
abstract: Flat inferior vena cava (IVC) on ultrasound examination has been shown to correlate with hypovolemic status. We hypothesize that a flat IVC on limited echocardiogram (LTTE) performed in the emergency room (ER) correlates with poor prognosis in acutely ill surgical patients. We conducted  a retrospective review of all patients undergoing LTTE in the ER from September 2010 until June 2011. IVC diameter was estimated by subxiphoid window. Flat IVC was defined as diameter less than 2 cm. Fat IVC was defined as diameter greater than 2 cm. Need for intensive care unit admission,  blood transfusion requirement, mortality, and need for emergent operation between patients with flat versus Fat IVC were compared. One hundred one hypotensive patients had LTTE performed in the ER. Average age was 38 years. Admission diagnosis was blunt trauma (n = 80), penetrating  trauma (n = 13), acute care surgery pathology (n = 7), and burn (n = 1). Seventy-four patients had flat IVC on initial LTTE. Compared with those with fat IVC, flat patients were found have higher rates of intensive care unit admission (51.3 vs 14.8%; P = 0.001), blood transfusion  requirement (12.2 vs 3.7%), and mortality (13.5 vs 3.7%). This population also underwent emergent surgery on hospital Day 1 more often (16.2 vs 0%; P = 0.033). Initial flat IVC on LTTE is an indicator of hypovolemia and a predictor of poor outcome.
authors.affiliation: Trauma, Critical Care and Emergency Medicine, Virginia Commonwealth University, Richmond, Virginia, USA. pferrada@mcvh-vcu.edu
authors.forename: Paula
authors.initials: P
authors.lastname: Ferrada
authors.forename: Poornima
authors.initials: P
authors.lastname: Vanguri
authors.forename: Rahul J
authors.initials: RJ
authors.lastname: Anand
authors.forename: James
authors.initials: J
authors.lastname: Whelan
authors.forename: Therese
authors.initials: T
authors.lastname: Duane
authors.forename: Luke
authors.initials: L
authors.lastname: Wolfe
authors.forename: Rao
authors.initials: R
authors.lastname: Ivatury
mesh_terms: D000328:Adult; D000368:Aged; D001811:Blood Volume Determination / Q000379:methods; D002056:Burns / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D015331:Cohort Studies; D016638:Critical Illness / Q000401:mortality / Q000628:therapy; D004452:Echocardiography / Q000379:methods; D004630:Emergencies; D004636:Emergency Service, Hospital; D005260:Female; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D020896:Hypovolemia / Q000000981:diagnostic imaging* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D014193:Trauma Centers; D018608:Ultrasonography, Doppler / Q000379:methods; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging* / Q000473:pathology; D014949:Wounds, Nonpenetrating / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D014950:Wounds, Penetrating / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*