Incidence and mortality of perioperative cardiac events in cervical spine surgery

Abstract

Study design: Retrospective database analysis.

Objective: To determine the national incidence, mortality, and risk factors for perioperative cardiac complications associated with cervical spine surgery in the United States.

Summary of background data: Perioperative myocardial infarctions and cardiac failure are leading causes of mortality in noncardiac surgery. The incidence of these complications has not been reported in cervical spine surgery.

Methods: Data from the Nationwide Inpatient Sample was obtained from 2002-2009. Patients undergoing anterior or posterior cervical fusion and posterior cervical decompression without fusion for degenerative etiologies were identified. Only elective admissions were included. Incidences of cardiac complications were identified and patient demographics, hospital costs, length of stay, and mortality were compared for each group. Logistic regression was used to identify independent predictors of cardiac complications.

Results: A total of 214,900 elective cervical spine procedures were identified in the United States from 2002-2009. Overall, there were 4.0 cardiac events per 1000 cases. For individual procedures, the incidence was 11.6 per 1000 posterior cervical fusions, 5.2 per 1000 posterior cervical decompressions, and 3.2 per 1000 anterior cervical fusions. Patients with cardiac events were statistically older with greater comorbidities (P < 0.0005). Across all cohorts, length of stay increased an additional 4.5 days, hospital costs increased $13,435, and mortality increased from 0.8 to 65.3 deaths per 1000 cases in the presence of a cardiac event (P < 0.0005). Logistic regression analysis demonstrated that independent predictors for cardiac events included age 65 years or more, multilevel fusions, acute blood-loss anemia, congestive heart failure, fluid/electrolyte disorders, and pulmonary circulation disorders.

Conclusion: Our results demonstrate an overall incidence of 4.0 cardiac events per 1000 cervical spine surgical procedures. Older patients with greater comorbid risk factors, particularly cardiovascular diseases, were at significantly increased risk for cardiac complications. Due to the large impact cardiac events have on health care utilization and mortality, we recommend thorough risk stratification for older patients undergoing elective cervical spine procedures.

Level of evidence: 3.