Incidence and prediction of major cardiovascular complications in head and neck surgery.

BACKGROUND: Patients with head and neck squamous cell carcinoma (HNSCC) usually have a history of tobacco and alcohol abuse. These 2 intoxications not only are main oncologic risk factors but also show a strong causal relationship with certain comorbid conditions. Examples are coronary artery disease, stroke, renal dysfunction, and heart failure, which are all proven major risk factors for an adverse postoperative outcome after stressful noncardiac surgery. Preoperative identification of these conditions could lead to preventive measures in patients with HNSCC that undergo extensive surgery. Preventing morbidity and mortality is of medical and economical importance.
METHODS: All comorbidity of 135 consecutive patients with HNSCC that underwent extensive oncologic and reconstructive surgery as the first form of treatment between 2001 and 2007 was investigated. Based on these data, a Lee Cardiac Risk Index (LCRI) Score and an overall Adult Comorbidity Evaluation (ACE-27) severity score were calculated. The predictive value of these scores and the American Society of Anesthesiologists' (ASA) classification toward major cardiovascular complication development were investigated. Major cardiovascular complications were defined as: cardiac death, nonfatal myocardial infarction, heart failure, and cardiac arrhythmias. The impact of these complications on duration of hospitalization, medical costs, and short-term mortality (defined as death within 6 months after primary tumor diagnosis) were investigated as well. The cardioprotective effect of preoperatively prescribed beta blockers and statins are discussed.
RESULTS: Twenty-two patients developed 23 major cardiovascular complications (16.3%). In univariate and multivariate analyses, a higher LCRI score was associated with an increased risk for major cardiovascular complications, as was an age >70 years (all values of p < .01). The area under the receiver operating characteristics (ROC) curve (AUC) for the multivariate model was 0.84, indicating a good prognostic value. In univariate and multivariate analysis, a higher ACE-27 score was associated with an increased risk for major cardiovascular complications, as was as age >70 years (all values of p < .01). The AUC for this model was 0.84, indicating a performance similar to that of the LCRI score model. No statistically significant results were found for the ASA scores (p = .38). Preoperative beta-blocker use showed a significant cardioprotective function in univariate analysis, whereas statins did not. The mean duration of hospitalization was prolonged by 7 days in patients with a major cardiovascular complication. In economic terms, this means a cost increase of at least 3500 euros. None of the patients died during admission because of a major cardiovascular complication. The short-term mortality rate was 11.1%, but no specific cardiovascular cause of death was reported in these patients.
CONCLUSIONS: Prevention of major complication occurrence after extensive HNSCC surgery is of medical and economic importance. Our results show that the ACE-27 and the LCRI are suitable instruments for preoperative major cardiovascular complication risk assessment. Addition of the variable age >70 years shows an improvement in predictive value of both instruments. Because of its simplicity we advise the implementation of the LCRI into preoperative HNSCC screening protocols. We advise the exploration of low-dose long-acting beta blockers as a preventive treatment strategy.