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Resectability with Impaired Pulmonary Function: Reply
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The Annals of Thoracic Surgery Vol 28 No 5 November 1979
Resectability with Impaired Pulmonary Function To the Editor: After reviewing the paper “Extending Resectability for Carcinoma of the Lung in Patients with Impaired Pulmonary Function” by Drs. Peters, Clausen, and Tisi (Ann Thorac Surg 26:250, 1978), and its discussion, I realized that I disagree with many of the’ statements and conclusions. A number of years ago, I [3] evaluated and reported my experience, which led me to the conclusion that the most discriminating test for predicting a patient’s ability to withstand pulmonary resection is determination of pulmonary artery pressure. I did not find that timed vital capacity, vital capacity, or other ventilatory tests were reliable indicators preoperatively. Furthermore, other tests such as electrocardiography and exercise tolerance were of little assistance. Subsequent experience has confirmed these original observations. In a previous study, I [l] did not find an absolute correlation between the amount of lung resected and ventilatory disability. In my experience, resection of one to seven segments yielded the same effects. All patients who had exploratory thoracotomy without pulmonary resection or with resection of less than eight segments behaved in a similar manner. Ventilatory capacity returned to preoperative levels only after approximately six weeks. Bilateral thoracotomy produced qualitatively similar results but quantitatively twice the disability [2]. The type of incision did not influence results, and use of antibiotics, analgesics, physiotherapy, blow bottles, and psychological encouragement did not affect the recovery rate. In a later study, I [4] was unable to demonstrate that recent preoperative smoking had a deleterious effect on results. I agree with Drs. Peters, Clausen, and Tisi that ”Differences in patient populations . . . make i t difficult to draw meaningful conclusions . . .” unless criteria are carefully established and results are subjected to careful statistical analysis. Although many of the suggestions made by Dr. Peters and co-workers regarding preoperative, intraoperative, and postoperative management of patients with poor cardiorespiratory reserve are philosophically attractive, there unfortunately is little objective evidence that they are of value.
David V . Pecora, M . D . Surgical Service, Veterans Administration, V A Center 1600 Kirkwood H w y Wilmington, DE 19805 References 1. Pecora DV: Progressive changes in ventilation
following pulmonary resection. Surg Gynecol Obstet 103:455, 1956 2. Pecora DV: Progressive changes in ventilation
following bilateral pulmonary resection. Surg Gynecol Obstet 109:89, 1959 3. Pecora DV: Evaluation of cardiopulmonary reserve in candidates for chest surgery. J Thorac Cardiovasc Surg 44:60, 1962 4. Pecora DV: Predictability of effects of abdominal and thoracic surgery upon pulmonary function. Ann Surg 170:101, 1969
Reply Dr. Pecora [2] cited one of his studies as the basis for his discussion of our preoperative evaluation of patients who are candidates for pulmonary resection. The methods for measuring pulmonary function are different from those we used. Also, the patients reported had about 60% of normal a s the lowest 3second timed vital capacity. This is probably higher than the value we used to classify patients as high risk except for the best 5 or 6 patients in our poor function group. It suggests his patients were not as disabled as ours. None of us knows the exact predictability of these tests because we disd not operate on all patients regardless of functional level. Measurement of pulmonary artery pressure at rest was not discriminatory in the study by Fee and co-workers [l], but with exercise stress was useful. We would agree that pulmonary artery pressure measurements made during exercise contribute additional information. Of course, the test should be done preoperatively, not intraoperatively. The failure to show correlation between ”the amount of lung resected and ventilatory disability” is evidence of the importance of chest cage function, which we stress in our discussion. Ik may be true in Delaware that postoperative care is either of no importance or cannot be demonstrated to be effective. Despite Dr. Pecora’s contention, we do not intend to do a double blind study to prove “objectively” the benefits of treatment that makes good sense from an understanding of the physiological derangements produced by pulmonary resection.
Richard M . Peters, M . D . Division of Cardiothoracic Surgery University of California Medical Center, Sun Diego 225 W Dickinson St Sun Diego, C A 92103
References 1. Fee HJ, Holmes EC, Gewirtz HS, et al: Role of
pulmonary vascular resistance measurements in preoperative evaluation of candi’dates for pulmonary resection. J Thorac Cardiovasc Surg 75:519, 1978 2. Pecora DV: Evaluation of cardiopulmonary reserve in candidates for chest surgery. J Thorac Cardiovasc Surg 44:60, 1962
The Annals of Thoracic Surgery Vol 28 No 5 November 1979
Resectability with Impaired Pulmonary Function To the Editor: After reviewing the paper “Extending Resectability for Carcinoma of the Lung in Patients with Impaired Pulmonary Function” by Drs. Peters, Clausen, and Tisi (Ann Thorac Surg 26:250, 1978), and its discussion, I realized that I disagree with many of the’ statements and conclusions. A number of years ago, I [3] evaluated and reported my experience, which led me to the conclusion that the most discriminating test for predicting a patient’s ability to withstand pulmonary resection is determination of pulmonary artery pressure. I did not find that timed vital capacity, vital capacity, or other ventilatory tests were reliable indicators preoperatively. Furthermore, other tests such as electrocardiography and exercise tolerance were of little assistance. Subsequent experience has confirmed these original observations. In a previous study, I [l] did not find an absolute correlation between the amount of lung resected and ventilatory disability. In my experience, resection of one to seven segments yielded the same effects. All patients who had exploratory thoracotomy without pulmonary resection or with resection of less than eight segments behaved in a similar manner. Ventilatory capacity returned to preoperative levels only after approximately six weeks. Bilateral thoracotomy produced qualitatively similar results but quantitatively twice the disability [2]. The type of incision did not influence results, and use of antibiotics, analgesics, physiotherapy, blow bottles, and psychological encouragement did not affect the recovery rate. In a later study, I [4] was unable to demonstrate that recent preoperative smoking had a deleterious effect on results. I agree with Drs. Peters, Clausen, and Tisi that ”Differences in patient populations . . . make i t difficult to draw meaningful conclusions . . .” unless criteria are carefully established and results are subjected to careful statistical analysis. Although many of the suggestions made by Dr. Peters and co-workers regarding preoperative, intraoperative, and postoperative management of patients with poor cardiorespiratory reserve are philosophically attractive, there unfortunately is little objective evidence that they are of value.
David V . Pecora, M . D . Surgical Service, Veterans Administration, V A Center 1600 Kirkwood H w y Wilmington, DE 19805 References 1. Pecora DV: Progressive changes in ventilation
following pulmonary resection. Surg Gynecol Obstet 103:455, 1956 2. Pecora DV: Progressive changes in ventilation
following bilateral pulmonary resection. Surg Gynecol Obstet 109:89, 1959 3. Pecora DV: Evaluation of cardiopulmonary reserve in candidates for chest surgery. J Thorac Cardiovasc Surg 44:60, 1962 4. Pecora DV: Predictability of effects of abdominal and thoracic surgery upon pulmonary function. Ann Surg 170:101, 1969
Reply Dr. Pecora [2] cited one of his studies as the basis for his discussion of our preoperative evaluation of patients who are candidates for pulmonary resection. The methods for measuring pulmonary function are different from those we used. Also, the patients reported had about 60% of normal a s the lowest 3second timed vital capacity. This is probably higher than the value we used to classify patients as high risk except for the best 5 or 6 patients in our poor function group. It suggests his patients were not as disabled as ours. None of us knows the exact predictability of these tests because we disd not operate on all patients regardless of functional level. Measurement of pulmonary artery pressure at rest was not discriminatory in the study by Fee and co-workers [l], but with exercise stress was useful. We would agree that pulmonary artery pressure measurements made during exercise contribute additional information. Of course, the test should be done preoperatively, not intraoperatively. The failure to show correlation between ”the amount of lung resected and ventilatory disability” is evidence of the importance of chest cage function, which we stress in our discussion. Ik may be true in Delaware that postoperative care is either of no importance or cannot be demonstrated to be effective. Despite Dr. Pecora’s contention, we do not intend to do a double blind study to prove “objectively” the benefits of treatment that makes good sense from an understanding of the physiological derangements produced by pulmonary resection.
Richard M . Peters, M . D . Division of Cardiothoracic Surgery University of California Medical Center, Sun Diego 225 W Dickinson St Sun Diego, C A 92103
References 1. Fee HJ, Holmes EC, Gewirtz HS, et al: Role of
pulmonary vascular resistance measurements in preoperative evaluation of candi’dates for pulmonary resection. J Thorac Cardiovasc Surg 75:519, 1978 2. Pecora DV: Evaluation of cardiopulmonary reserve in candidates for chest surgery. J Thorac Cardiovasc Surg 44:60, 1962