Pre-Operation Evaluation of Thoracic Surgery Patient: Spirometry and Pulmonary Exercise test (PXT) 吳惠東

Risks of Operation Operation Site Operation Site Extent of operation Extent of operation Patients ’ reserve Patients ’ reserve Anesthesia Anesthesia Operator skill Operator skill

Pulmonary Risks by Operation Sites Extra-thoracic Extra-thoracic Extremities Extremities Low abdomen Low abdomen Upper abdomen Upper abdomen Intra-thoracic Intra-thoracic No Lung resection No Lung resection Lung parenchyma resection Lung parenchyma resection

Overview ~ 30% of patients undergoing lung resection develop cardiopulmonary complications with a 30-day mortality varying between 0.6% and 5%, depending on the extent of lung resection. ~ 30% of patients undergoing lung resection develop cardiopulmonary complications with a 30-day mortality varying between 0.6% and 5%, depending on the extent of lung resection. Mortality: 5.7% after pneumonectomy, 4.4% after bilobectomy, 3.9% after lobectomy. Mortality: 5.7% after pneumonectomy, 4.4% after bilobectomy, 3.9% after lobectomy.

Lung Function Test in Surgery Patients Indication Indication All Chest surgery patients All Chest surgery patients History of lung/airway disease History of lung/airway disease Heavy smoker Heavy smoker Exertional dyspnea Exertional dyspnea Risks evaluation Risks evaluation Peri-operation Peri-operation Subacute, long-term Subacute, long-term Avoid pulmonary complication Avoid pulmonary complication

Preoperative evaluation Identifying patients at risk  evaluating the risk  finding modified factors to decrease risk. Identifying patients at risk  evaluating the risk  finding modified factors to decrease risk. Detailed medical history, physical examination Detailed medical history, physical examination Patient ’ s functional capacity, the degree of limitation of activity Patient ’ s functional capacity, the degree of limitation of activity Pulmonary function testing: spirometry, lung volumes, diffusing capacity, oximetry, and arterial blood gases. Pulmonary function testing: spirometry, lung volumes, diffusing capacity, oximetry, and arterial blood gases. Radionuclide lung scanning, exercise testing, invasive pulmonary hemodynamic measurements, and risk stratification analysis. Radionuclide lung scanning, exercise testing, invasive pulmonary hemodynamic measurements, and risk stratification analysis. Respir Med 2004; 98(7): Chest 2003;123:

Preoperative evaluation: Spirometry Maximal voluntary ventilation < 50% of predicted and FVC < 70% of predicted were associated with a 40% risk for death. Maximal voluntary ventilation < 50% of predicted and FVC < 70% of predicted were associated with a 40% risk for death. FEV1 FEV1 - Most common PFT used for prediction - Accounts for variability in the gender and size of patients for lung resection - The important determinant of FEV1 cut-off value is the extent of lung resection. - the incidence of postoperative pulmonary complications in patients with FEV1 2 L. Respir Med 2004; 98(7): Chest 2003;123:

Spirometry for Lung Resection Pneumonectomy: Pneumonectomy: FEV1 >2L; MVV >55% of predicted; FEV1 >2L; MVV >55% of predicted; FEF 25–75% >1.6 L/s. FEF 25–75% >1.6 L/s. Lobectomy Lobectomy FEV1 >1L; MVV >40% of predicted; FEV1 >1L; MVV >40% of predicted; FEF 25–75% >0.6 L/s. FEF 25–75% >0.6 L/s. Segmentectomy or wedge resection Segmentectomy or wedge resection FEV1 >0.6L; MVV >40% of predicted; FEV1 >0.6L; MVV >40% of predicted; FEF 25–75% >0.6 L/s. FEF 25–75% >0.6 L/s. Chest 2003;123:

DLCO Independent predictor of postoperative outcome Independent predictor of postoperative outcome Reflects alveolar membrane integrity and pulmonary capillary blood flow in the patient ’ s lungs. Reflects alveolar membrane integrity and pulmonary capillary blood flow in the patient ’ s lungs. Patients with DLCO≥70% predicted had a much lower postpneumonectomy complication rate than patients with DLCO<70% predicted. Patients with DLCO≥70% predicted had a much lower postpneumonectomy complication rate than patients with DLCO<70% predicted. A low DLCO identifies patients with significant emphysema, and reduced pulmonary capillary vascular bed A low DLCO identifies patients with significant emphysema, and reduced pulmonary capillary vascular bed  postoperative pulmonary hypertension, arrhythmia, cardiac dysfunction  postoperative pulmonary hypertension, arrhythmia, cardiac dysfunction Respir Med 2004; 98(7): Chest 2003;123:

Quantitative Lung Scan Perfusion studies remained the most accurate Perfusion studies remained the most accurate ppoFEV1 = preoperative FEV1 x % of radioactivity contributed by nonoperated lung ppoFEV1 = preoperative FEV1 x % of radioactivity contributed by nonoperated lung ppoFEV1 = preoperative FEV1 x (1-[S x 5.26] /100) ppoFEV1 = preoperative FEV1 x (1-[S x 5.26] /100) - S : number of bronchopulmonary segments involved. predicted postoperative FEV1 < 1L  physiologic inoperability. predicted postoperative FEV1 < 1L  physiologic inoperability. predicted postoperative FEV1 < 0.8L  surgical inoperability. predicted postoperative FEV1 < 0.8L  surgical inoperability. - Patients with COPD with an FEV1 <0.8L had CO2 retention. ( these studies were not corrected for age, height, or sex.) Respir Med 2004; 98(7): Chest 2003;123:

Preoperative evaluation – methods Expected loss of function Expected loss of function = preoperative FEV1 x No. of segments in lobe to be resected = preoperative FEV1 x No. of segments in lobe to be resected total No. of segments in the whole lung total No. of segments in the whole lung - higher mortality was associated with ppo FEV1 <40%  ppoFEV1 <40% is a safe preoperative criterion for operability. - higher mortality was associated with ppo DLCO <40%  the best predictor of postoperative respiratory failure. Chest 2003;123:

Predict of Post-Operation FEV1 Pneumonectomy Pneumonectomy Pre-op FEV1 X (% of perfusion) Lobectomy Lobectomy Pre-op FEV1 X (# Segment section) / (# Total segment) Acceptable post-operation lung function Acceptable post-operation lung function FEV1 > 700 ml, or 40% predict FEV1 > 700 ml, or 40% predict VO2max > 10 ml/kg/ml VO2max > 10 ml/kg/ml

Pulmonary Exercise Test (PXT) Low ppoFEV1: <0.8 ~1 L or 35 ~40% of predicted values  exercise testing Low ppoFEV1: <0.8 ~1 L or 35 ~40% of predicted values  exercise testing Stresses the entire cardiopulmonary & oxygen delivery sys Stresses the entire cardiopulmonary & oxygen delivery sys Respir Med 2004; 98(7): Chest 2003;123:

Oxygen uptake VO 2 is related to age, sex, weight, and type of work performed VO 2 is related to age, sex, weight, and type of work performed VO 2 max >20 mL/kg/min will tolerate surgery with acceptable morbidity and mortality VO 2 max >20 mL/kg/min will tolerate surgery with acceptable morbidity and mortality

PXT Eugene et al VO2max > 1 L/min: Little complication VO2max > 1 L/min: Little complication Smith et al VO2max > 20ml/kg/min  postoperative complications 10% VO2max > 20ml/kg/min  postoperative complications 10% VO2max 15~20ml/kg/min  postoperative complications 66% VO2max 15~20ml/kg/min  postoperative complications 66% VO2max < 15ml/kg/min  postoperative complications 100% VO2max < 15ml/kg/min  postoperative complications 100% Markos et al oxygen desaturation during a 12-min walk, ppoDLCO, and ppo FEV1 were more reliable predictors of postoperative mortality oxygen desaturation during a 12-min walk, ppoDLCO, and ppo FEV1 were more reliable predictors of postoperative mortality Chest 2003;123:

Lung resection in lung cancer The mortality rate from lung resection surgery in lung cancer is reported to range from 7 to 11%. The mortality rate from lung resection surgery in lung cancer is reported to range from 7 to 11%. The 5-year survival rate after resection ranges from 55% (stage I disease) to 26% (stage II disease). The 5-year survival rate after resection ranges from 55% (stage I disease) to 26% (stage II disease). Curr Opin Pulm Med 2003;9:321-6 Chest 2003;123:

Pre-operative pulmonary function survey FEV1 > 2 L; MVV > 50 L FEV1 > 2 L; MVV > 50 L Operation Operation FEV1 1 L; MVV 1 L; MVV < 50 L Quantitative Perfusion scan, careful assessment Quantitative Perfusion scan, careful assessment FEV1 < 1L or 35% predict FEV1 < 1L or 35% predict No resection surgery No resection surgery

Preoperative evaluation Respir Med 2004; 98(7):

Assessment of Function Operability AJRCCM 1999;159:1450-6

Chest 2000;118: Postoperative complications

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