Impact of chronic renal insufficiency using serum creatinine vs glomerular filtration rate on perioperative clinical outcomes of carotid endarterectomy.

BACKGROUND

Several studies have reported conflicting results after carotid endarterectomy in patients with chronic renal insufficiency (CRI). However, only a few used glomerular filtration rate (GFR) (Modification of Diet in Renal Disease) in their analysis.

STUDY DESIGN

Nine hundred and forty carotid endarterectomies that had serum creatinine and GFR were analyzed. Patients were classified as normal (creatinine <1.5 mg/dL or GFR ≥60 mL/min/1.73 m(2)); moderate CRI (creatinine ≥1.5 to 2.9 mg/dL or GFR ≥30 to 59 mL/min/1.73 m(2)), and severe CRI (creatinine ≥3 mg/dL or GFR <30 mL/min/1.73 m(2)).

RESULTS

Using creatinine, perioperative stroke and major adverse event rates for normal, moderate CRI, and severe CRI were 2%, 3.5%, and 11.1% (p = 0.091) and 2.4%, 4.4%, and 11.1% (p = 0.089) vs 1.1%, 3.7%, and 5.4% (p = 0.018) and 1.8%, 4%, and 5.4% (p = 0.086) using GFR. Univariate logistic regression analysis showed that creatinine ≥1.5 mg/dL had an odds ratio of 2.1 for having early stroke/death vs an odds ratio of 3.5 (p = 0.009) for GFR <60 mL/min/1.73 m(2). A multivariate analysis showed that GFR <60 mL/min/1.73 m(2) had an odds ratio for early stroke/death of 3.7 (p = 0.013). Using creatinine, perioperative stroke rates for symptomatic patients were 2.8%, 2.6%, and 0% and 1.6%, 4.1%, and 11.1% (p = 0.045) for asymptomatic patients with normal, moderate CRI, and severe CRI vs 1.6%, 4.7%, and 9.1% for symptomatic patients (p = 0.09) and 1%, 3.2%, and 3.9% for asymptomatic patients (p = 0.074) using GFR. Perioperative major adverse event rates for symptomatic patients using creatinine were 3.2%, 2.6%, and 0%, and for asymptomatic patients 2.1%, 5.4%, and 11.1% (p = 0.048) vs 2.1%, 4.7%, and 9.1% for symptomatic patients and 1.7%, 3.7%, and 7.7% (p = 0.193) for asymptomatic patients using GFR. Moderate/severe CRI also had more cardiac (5.7% vs 2.4%; p = 0.072) and respiratory complications (2.5% vs 0.2%; p = 0.018).

CONCLUSIONS

Glomerular filtration rate (Modification of Diet in Renal Disease) was more sensitive in detecting perioperative stroke/death after carotid endarterectomy in patients with CRI. Patients with moderate/severe CRI had more major adverse events than normal patients.