Background:
Current preoperative risk assessment tools are often cumbersome, have limited
accuracy, and are poorly adopted. The Care Assessment Need (CAN) score, an
existing tool developed for primary care providers in the U.S. Veterans
Administration health-care system (VA), is automatically calculated for
individual patients using electronic health record data. Therefore, it could
present an efficient preoperative risk assessment tool. The aim of this
project was to determine if the CAN score can be repurposed as a
preoperative risk assessment tool for patients undergoing total knee
arthroplasty (TKA).
Methods:
A multicenter retrospective observational study was conducted using national
VA data from 2013 to 2016. The cohort included veterans who underwent TKA
identified through ICD-9 (International Classification of Diseases, Ninth
Revision), ICD-10, and CPT (Current Procedural Terminology) codes. The focus
of the study was the preoperative patient CAN score, a single numerical
value ranging from 0 to 99 (with a higher score representing greater risk)
that is automatically calculated each week using multiple data points in the
VA electronic health record. Study outcomes of interest were 90-day
readmission, prolonged hospital stay (>5 days), 1-year mortality, and
non-routine patient discharge.
Results:
The study included 17,210 veterans. Their median preoperative CAN score was
75, although there was substantial variability in patient CAN scores among
different facilities. A preoperative CAN score of >75 was significantly
associated with mortality (odds ratio [OR] = 3.54), prolonged length of
stay (OR = 1.97), 90-day readmission (OR = 1.65), and non-routine
discharge (OR = 1.57). The CAN score had good accuracy with a receiver
operating characteristic (ROC) curve value of >0.7 for all outcomes
except 90-day readmission.
Conclusions:
The CAN score can be leveraged as an extremely efficient way to risk-stratify
patients before TKA, with results that surpass other commonly available and
labor-intensive alternatives. As a result, this simple and efficient
solution is well positioned for broad adoption as a standardized decision
support tool.
Level of Evidence:
Prognostic
Level IV
. See Instructions for Authors for
a complete description of levels of evidence.