, Volume 471, Issue 9, pp 2737-2742
Date: 10 May 2013

CT Pulmonary Angiography After Total Joint Arthroplasty: Overdiagnosis and Iatrogenic Harm?

Topic
Hip

Abstract

Background

CT pulmonary angiography (CTPA) has become widely adopted to detect pulmonary embolism (PE) after total joint arthroplasty (TJA). CTPA is a sensitive tool, which has the ability to detect emboli that may be clinically insignificant. This may lead to iatrogenic harm from overtreatment.

Questions/purposes

The purpose of this study was to assess changing prevalence, mortality, treatment complications, and resource consumption associated with PE after TJA before and after the introduction of CTPA.

Methods

The Nationwide Inpatient Sample was used to identify 2,335,248 patients undergoing TJA from 1993 to 1998 before the introduction of CTPA and 6,321,671 patients from 1999 to 2008 after the introduction of CTPA. Bivariate and multivariate regression analysis was performed to compare changing prevalence of PE, mortality, potential treatment complications of anticoagulation, length of stay, and total charges before and after the introduction of CTPA in patients with PE.

Results

In-hospital diagnosis of PE after TJA increased (p < 0.001) from an average of 0.27% to 0.37% after the introduction of CTPA. All-cause mortality in patients with a diagnosis of PE decreased (p < 0.001) from 11.5% to 4.6% (odds ratio, 2.3; 95% confidence interval, 2.1–2.6) after the introduction of CTPA. Overall, PE was associated with increased (p < 0.001) risks for hematoma/seroma, postoperative infection, gastrointestinal bleed, and drug-related thrombocytopenia, although the prevalence of these complications has decreased after 1998 (p < 0.001). Length of stay doubled for patients with PE (both before and after CTPA) and total charges increased over 69% in both study periods for these patients.

Conclusions

Adoption of CTPA appears to be associated with an increase in the diagnosis of PE after TJA and an associated decrease in case-fatality. Although CTPA may improve our ability to diagnose PE and possibly reduce mortality, the observed decrease in case-fatality could also be explained by the overdiagnosis of clinically unimportant emboli. The diagnosis of PE was strongly associated with potential iatrogenic harm from anticoagulation and increased length of stay and hospital charges in this study, emphasizing the importance of further investigation to define the role of CTPA in the diagnosis and treatment of PE after TJA.

Level of Evidence

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Each author certifies that he or she, or a member of his or her immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article.
All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research editors and board members are on file with the publication and can be viewed on request.
A comment to this article is available at http://dx.doi.org/10.1007/s11999-013-3108-2.