A model to predict the immediate postoperative FEV1 following major lung resections

Lung function predicts pulmonary complications regardless of the surgical approach

BACKGROUND

Although postoperative predicted forced expiratory volume in the first second and diffusing capacity of lung (ppoFEV1% and ppoDLCO%, respectively) have been identified as independent predictors of postoperative pulmonary complications after open lobectomy, it has been suggested that their predictive abilities may not extend to patients undergoing minimally invasive lobectomy.

METHODS

We evaluated outcomes in 805 patients undergoing isolated lobectomy through open (n = 585) or minimally invasive approaches (n = 220) using a prospective database. Demographic and physiologic data were extracted and compared with complications classified as pulmonary, cardiac, other, mortality, and any.

RESULTS

Patients included 428 women and 377 men; mean age was 65.0 years. Minimally invasive patients were older (66.6 versus 64.3 years, p = 0.006), had better ppoFEV1% (71.5% versus 65.6%, p < 0.001) and performance status (0,1 94.1% versus 88.4%, p = 0.017), and less often underwent induction therapy (0.5% versus 4.8%, p = 0.003). Pulmonary and other complications were less common after minimally invasive lobectomy (3.6% versus 10.4%, p = 0.0034; 8.6% versus 15.8%, p = 0.008). Operative mortality occurred in 1.4% of minimally invasive patients and 3.9% of open patients (p = 0.075). Pulmonary complication incidence was related to predicted postoperative lung function for both minimally invasive and open approaches. On multivariate analysis with stratification for stage, ppoFEV1% and ppoDLCO% were predictive of pulmonary complications for both minimally invasive and open approaches.

CONCLUSIONS

Our results suggest that the predictive abilities of ppoFEV1% and ppoDLCO% are retained for minimally invasive lobectomy and can be used to estimate the risk of pulmonary complications.

Patients with chronic pulmonary disease

Chronic pulmonary disease is common among the surgical population and the importance of a thorough and detailed preoperative assessment is monumental for minimizing morbidity and mortality and reducing the risk of perioperative pulmonary complications. These comorbidities contribute to pulmonary postoperative complications, including atelectasis, pneumonia, and respiratory failure, and can predict long-term mortality. The important aspects of the preoperative assessment for patients with chronic pulmonary disease, and the value of preoperative testing and smoking cessation, are discussed. Specifically discussed are preoperative pulmonary assessment and management of patients with chronic obstructive pulmonary disease, asthma, restrictive lung disease, obstructive sleep apnea, and obesity.

American College of Chest Physicians and Society of Thoracic Surgeons consensus statement for evaluation and management for high-risk patients with stage I non-small cell lung cancer

BACKGROUND

The standard treatment of stage I non-small cell lung cancer (NSCLC) is lobectomy with systematic mediastinal lymph node evaluation. Unfortunately, up to 25% of patients with stage I NSCLC are not candidates for lobectomy because of severe medical comorbidity.

METHODS

A panel of experts was convened through the Thoracic Oncology Network of the American College of Chest Physicians and the Workforce on Evidence-Based Surgery of the Society of Thoracic Surgeons. Following a literature review, the panel developed 13 suggestions for evaluation and treatment through iterative discussion and debate until unanimous agreement was achieved.

RESULTS

Pretreatment evaluation should focus primarily on measures of cardiopulmonary physiology, as respiratory failure represents the greatest interventional risk. Alternative treatment options to lobectomy for high-risk patients include sublobar resection with or without brachytherapy, stereotactic body radiation therapy, and radiofrequency ablation. Each is associated with decreased procedural morbidity and mortality but increased risk for involved lobe and regional recurrence compared with lobectomy, but direct comparisons between modalities are lacking.

CONCLUSIONS

Therapeutic options for the treatment of high-risk patients are evolving quickly. Improved radiographic staging and the diagnosis of smaller and more indolent tumors push the risk-benefit decision toward parenchymal-sparing or nonoperative therapies in high-risk patients. Unbiased assessment of treatment options requires uniform reporting of treatment populations and outcomes in clinical series, which has been lacking to date.

[Preoperative evaluation and risk estimation in thoracic surgery]

Preoperative evaluation of patients undergoing lung resection remains an interdisciplinary challenge. Despite substantial progress in anesthesiology, intensive care medicine and surgery, mortality of patients undergoing pneumonectomy remains high at 5-9%. Guidelines were developed to identify patients with an increased perioperative risk for morbidity and mortality. These guidelines are focused around the forced expiratory capacity (FEV) measured by spirometry, following further investigations in patients with limited FEV(1). Extended testing includes measurement of the diffusion capacity, calculation of postoperative predicted values of lung function and spiroergometry to determine maximal oxygen uptake. In this article the methods to measure parameters of lung function and gas exchange are described and evaluated in the context of the current guidelines.

Future trends in preoperative evaluation

Preoperative evaluation before lung resection has been frequently addressed in modern medical literature. Actual or predicted pulmonary volumes are considered relevant to predict the risk of surgery. Nevertheless, ppoFEV1 underestimates the real functional loss in the immediate postoperative period when most of the complications occur. Not all patients, however, have comparable functional changes after lobectomy. Minimal impairment or even improvements have been demonstrated in COPD cases after lobectomy. Efforts should be directed to an accurate prediction of the immediate postoperative pulmonary volumes for a better evaluation of high-risk patients caused by respiratory impairment. Future developments are needed on the role of measuring preoperative DLCO and how to evaluate a patient's general cardiorespiratory status. Evidence underlines the relevance of routine evaluation of preoperative DLCO at rest or, better, during exercise for a thorough assessment of patient's capability to adapt to a stressful situation (Fig. 3). Only by improving knowledge about the general condition of the patient, can one assess the physiologic response to surgery. Widespread use of sophisticated or simple exercise tests and measurements or daily activity using motion detectors can identify high-risk patients with otherwise acceptable pulmonary volumes. Another suggested investigation issue is to develop different relevant outcome parameters, not only from the surgeon's point of view but also from the patient's perspective, such as postoperative QOL-related variables or delayed outcomes. Finally, multidisciplinary investigation teams, including experts in mathematical modeling, are essential to improve the quality and validity of the developed models. Although knowledge about perioperative physiologic changes has increased, clinicians are still far from finding a way to put all this knowledge down and make it applicable for an individual patient. Multicentric cooperation and evaluation of large prospectively recorded databases are essential to develop evidence-based clinical guidelines on preoperative evaluation.