title: Impedance plethysmography in the diagnosis of asymptomatic deep vein thrombosis in hip surgery. A venography-controlled study.
abstract: We prospectively evaluated the accuracy of computerized impedance plethysmography (CIP) in the diagnosis of asymptomatic deep vein thrombosis (DVT) in 246 consecutive high-risk patients scheduled for hip surgery, with bilateral venography used for comparison. The CIP was performed as a surveillance program every third day. If the CIP remained negative, bilateral venography was performed on postoperative day 10 +/- 1 or on day of treatment 14 +/- 1 in nonoperated-on patients. If the CIP became positive, venography was performed within 24 hours. The sensitivity and specificity of CIP for proximal and distal DVT were 19% (confidence interval [CI], 13% to 24%) and 91% (CI, 87% to 94%), respectively. The positive and negative predictive values were 52% (CI, 38% to 65%) and 70% (CI, 65% to 74%), respectively. The sensitivity and specificity of CIP for proximal DVT were 24% (CI, 13% to 34%) and 90% (CI, 87% to 94%), respectively; the positive and negative predictive values were 31% (CI, 20% to 51%) and 87% (CI, 83% to 90%), respectively. We conclude that, because of its low sensitivity, CIP cannot be used in the surveillance of DVT in high-risk patients or for outcome measurements in clinical trials on DVT prophylaxis.
authors.affiliation: Department of Medical Semiotics, University of Perugia, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Agnelli
authors.forename: B
authors.initials: B
authors.lastname: Cosmi
authors.forename: V
authors.initials: V
authors.lastname: Ranucci
authors.forename: C
authors.initials: C
authors.lastname: Renga
authors.forename: S
authors.initials: S
authors.lastname: Mosca
authors.forename: L
authors.initials: L
authors.lastname: Lupattelli
authors.forename: P
authors.initials: P
authors.lastname: Di Filippo
authors.forename: E
authors.initials: E
authors.lastname: Rinonapoli
authors.forename: G G
authors.initials: GG
authors.lastname: Nenci
mesh_terms: D000368:Aged; D003871:Dermatan Sulfate / Q000627:therapeutic use; D005069:Evaluation Studies as Topic; D005260:Female; D006493:Heparin / Q000627:therapeutic use; D006621:Hip Joint / Q000601:surgery*; D006801:Humans; D008297:Male; D010690:Phlebography; D010992:Plethysmography, Impedance; D011183:Postoperative Complications / Q000517:prevention & control; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013924:Thrombophlebitis / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control
chemical_list: D003871:Dermatan Sulfate; D006493:Heparin