A prospective risk analysis of contemporary thoracic surgery

Genetics of postoperative complications following thoracic surgery

The field of complex trait-gene interaction research has expanded exponentially in recent years, and new insights into the ways patients respond to surgical stimuli have arisen from this body of work. From a physiological systems perspective, thoracic surgical procedures (thoracotomy in particular) represent a massive input stimulus, and it is, therefore, not surprising that approximately 30% of these patients experience an adverse postoperative event. The best risk prediction models have typically explained about 60% to 70% of the risk, leaving a large residual component unaccounted for. It is quite possible that there is a genetic (heritable) component to this residual risk. This article explores some of the concepts underlying gene-disease interactions, the preliminary work that has been done to date in this area, and finally discusses some of the more important methodological issues involved in complex trait association study design.

Risk factors for the development of postoperative complications after bronchial sleeve resection for malignancy: a univariate and multivariate analysis

BACKGROUND

This study was designed to identify risk factors responsible for postoperative complications after bronchoplastic procedures.

METHODS

Excluding sleeve pneumonectomies between January 1994 and December 2001, 108 patients underwent bronchoplastic procedures for bronchial malignancy. Prospectively documented data were age, gender, side, type of bronchial reconstruction, extended resection, histology, TNM stage, diseased lobe, and bronchial tumour occlusion. Cardiovascular (CV) risk factors included heart disease, arterial hypertension, cerebro-occlusive disease, peripheral artery disease of the lower extremities, diabetes mellitus, and abdominal aortic aneurysm. Patients were grouped according to the presence/absence of any CV risk factor and the absolute number of CV risk factors present (zero to four). Non-CV risk factors included neoadjuvant chemotherapy, alcoholism, lung disease, sleep apnea, history of recent pneumococcal sepsis, and repeat thoracotomy. Groups were assembled according to the presence or absence of any non-CV risk factor, neoadjuvant chemotherapy, and alcoholism. Respiratory risk factors included lung function and blood gas analysis. Groups were assembled according to the absolute number of respiratory risk factors in each person (zero to three) and the combination of respiratory and CV risk factors. Complications were defined as septic (pneumonia, empyema, brochopleural fistula, colitis) and aseptic. For univariate statistical analysis, t test, cross-tabulation, and chi2 test were used. All factors with a significance of p < 0.1 were entered into a binary backwards-stepwise logistic regression model.

RESULTS

The combination of respiratory and CV risk factors (p = 0.012, OR = 0.165) was predictive for overall complications. Coronary artery disease (p = 0.02, OR = 0.062) and the combination of two respiratory risk factors (p = 0.008, OR = 0.062) were predictive for septic complications. Peripheral artery disease (p = 0.024, OR = 0.28), moderate (p = 0.01, OR = 0.13) and severe chronic obstructive pulmonary disease (p = 0.018, OR = 0.11), and extended resections (p = 0.003, OR = 0.017.) were predictive for aseptic complications.

CONCLUSIONS

Comorbidity significantly influences the postoperative complication rate and is therefore crucial for evaluation of patients for bronchoplastic procedures. Different risk factors are responsible for the occurrence of septic and aseptic complications after bronchoplastic procedures.

Lung cancer surgery--preoperative risk assessment and patient selection

Lung resection remains the therapy of choice offering the greatest potential for cure in non spread lung cancer. As these procedures have a significant rate of cardiopulmonary complications, risk assessment and evaluation of functional operability is essential for successful resectional surgery. The most valuable parameters for evaluation of lung function and risk assessment are FEV1, DLCO and VO2max as well as the calculation of predicted postoperative lung function. With preoperative preparatory physical therapy and treatment of comorbidities, also marginal patients may become operable for resectional surgery.

Identification of prognostic factors determining risk groups for lung resection

BACKGROUND

Pulmonary resection belongs to a group of surgical procedures with significant morbidity and mortality. The aims of this study were to classify postoperative complications and to identify prognostic factors determining risk group.

METHODS

In a prospective study 500 patients undergoing lung resection (wedge resection, n = 141; lobectomies, n = 245; bilobectomies, n = 12; and pneumonectomies, n = 102) were included. In 178 patients (36%) pulmonary resections were extended to structures or thoracic organs. Sleeve resection of the bronchus to preserve lung parenchyma was performed in 22 patients.

RESULTS

Classification of postoperative complications fell into four categories: patients without postoperative complications; patients with moderate complications (n = 137); patients with severe complications (n = 38); and death (n = 33). Factors adversely affecting postoperative complications by multivariate analysis included pulmonary pathology, bronchoplastic technique, forced expiratory volume in 1 second (FEV1), extended resection, type of lung resection, comorbidity indices, and preoperative chemotherapy. Four risk groups were determined. Risk group I (n = 60) with the best prognosis included patients with FEV1 greater than or equal to 80% undergoing wedge resection for a benign lesion or metastasis. Risk group II (n = 161) included patients with FEV1 greater than or equal to 80% undergoing major pulmonary resection for a benign lesion or metastasis or lung cancer, or patients with FEV1 less than 80% undergoing wedge resection for benign lesion or metastasis. Risk group III (n = 233) with a fair prognosis included patients with comorbidity indices less than 4 and FEV1 greater than or equal to 80% undergoing extended pulmonary resection for a benign lesion or metastasis or lung cancer, or patients with FEV1 less than 80% and emphysema. Risk group IV (n = 46) with the worst prognosis included patients with FEV1 less than 80% undergoing an extended lung resection or bronchoplastic procedures for a benign lesion or metastasis or lung cancer, or patients with comorbidity indices greater than or equal to 4 undergoing extended lung resection for lung cancer.

CONCLUSIONS

In a prospective study, based on these prognostic factors, a practical, easy-to-use risk group system of lung resection is proposed as a tool to aid the decision to perform lung resection.