Robert S. Crawford, Christopher J. Abularrage, Mark F. Conrad, Todd R. Lancaster, Michael T. Watkins, Richard P. Cambria, Glenn M. LaMuraglia
Massachusetts General Hospital, Boston, MA
OBJECTIVES: Infrainguinal surgical bypass (BPG) is the gold-standard for lower extremity revascularization despite significant 30-day morbidity and mortality (MM). The goal of this study is to determine the ability of pre-operative functional status to predict perioperative MM and thus identify patients who may be unsuitable for BPG.
METHODS: All BPG data between 1/1/05-12/31/07 from the prospective NSQIP database was analyzed. The study end-point was 30-day MM. Patients were stratified by preoperative functional status: independent (IND) vs. dependent (DEP), defined as requiring assistance in performing activities of daily living. Associated patient demographic/clinical data were analyzed using univariate and multivariate methods with the construction of high risk composites.
RESULTS: There were 5,639 BPG patients (4600 (81.6%) IND and 1039 (18.4%) DEP). DEP patients were significantly older (71.6±11.8 vs. 66.8 ± 11.8 years; p<0.0001), had more COPD (16.7 vs. 11.4%; p<0.0001), diabetes (54.2 vs. 40.7%; p<0.0001), current dialysis (16.4 vs. 5.6%; p<0.0001), and critical limb ischemia (64.6 vs. 44%; p<0.0001). DEP patients had a higher incidence of death (6.1 vs. 1.5%; p<0.0001) and major complications (30.3 vs. 14.2%; p<0.0001). DEP was a multivariate independent predictor of death (2.3[1.6-3.4]; p<0.0001), major complications (2.0[1.7-2.4]; p<0.0001) major systemic complications (2.5[1.9-3.2]; p<0.0001) and major operative site complications (1.6 [1.4-1.9]; p<0.0001). When combined with DEP, there were multiple variables that contributed to high-risk composites, e.g., the successive addition of + hemodyalisis, + emergency surgery and + age ≥ 80 years increased the death rate 13-, 38- and 97-times respectively. For major complications, the successive addition of + emergency surgery, + Cr>1.8 and + rest pain increased the risk 5-, 7- and 11-times that of baseline.
CONCLUSIONS: Pre-operative DEP is a significant surrogate for comorbidities in addition to being an independent predictor of all major negative 30-day outcomes in BPG patients. Furthermore, when combined in high-risk composites with specific preoperative clinical variables, DEP is associated with prohibitive MM, thereby identifying patient cohorts that can be considered unsuitable for BPG.
AUTHOR DISCLOSURES: R.S. Crawford, None; C.J. Abularrage, None; M.F. Conrad, None; T.R. Lancaster, None; M.T. Watkins, None; R.P. Cambria, None; G.M. LaMuraglia, None.