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PubMed1991

The role of extrapleural pneumonectomy in malignant pleural mesothelioma. A Lung Cancer Study Group trial.

Malignant pleural mesothelioma is usually a fatal cancer for which operation has been the mainstay of treatment because chemotherapy and radiation are relatively ineffective. The choice of operation for malignant pleural mesothelioma remains controversial. Extrapleural pneumonectomy has been advocated because it allows complete removal of gross tumor and can be associated with long-term survival. To evaluate extrapleural pneumonectomy, we conducted a prospective multiinstitutional trial in patients with biopsy-proved previously untreated malignant pleural mesothelioma. Criteria for extrapleural pneumonectomy were (1) potentially completely resectable unilateral disease by computed tomography scan, (2) predicted postresection forced expiratory volume in 1 second greater than 1 L/sec, and (3) no other major medical problems. Patients who were not candidates for extrapleural pneumonectomy had a more limited operation with or without adjuvant therapy or had nonsurgical treatment. From September 1985 to June 1988 83 eligible patients (64 male, 19 female) were entered. The mean age for all patients was 59.7 years. Only 20 of the 83 patients (24%) underwent extrapleural pneumonectomy. Three of these 20 patients (15%) died postoperatively. The recurrence-free survival was significantly longer for the patients undergoing extrapleural pneumonectomy than for the other two groups (p = 0.03), but there was no difference in overall survival among the three groups. In univariate analyses, epithelial versus sarcomatoid and mixed histologic findings and platelet count less than 400,000 were associated with a better overall survival (p = 0.02), and performance status (Karnofsky less than 80) was predictive of recurrence (p = 0.02). In a multivariate analysis, histologic findings, sex, age, extrapleural pneumonectomy, weight loss, and performance status all had no significant impact on survival. Extrapleural pneumonectomy was associated with a greater likelihood of relapse in distant sites than were limited operation and nonsurgical treatment. We conclude that (1) only a small proportion of all patients with malignant pleural mesothelioma are candidates for extrapleural pneumonectomy, (2) extrapleural pneumonectomy carries a significant operative mortality and does not seem to improve overall survival compared with more conservative forms of treatment, (3) extrapleural pneumonectomy alters the patterns of relapse, and (4) factors previously thought to have an impact on survival in other series did not affect outcome in this trial.

Diaphragm↗

PubMed1990

Shock, transfusion, and pneumonectomy. Death is due to right heart failure and increased pulmonary vascular resistance.

To determine the physiologic cardiopulmonary abnormalities leading to death when pneumonectomy is required to stop bleeding in patients in hemorrhagic shock, we compared cardiopulmonary responses to resuscitation in pigs undergoing hemorrhagic shock alone, pneumonectomy alone, and hemorrhagic shock plus pneumonectomy. Four shock-plus-pneumonectomy pigs died acutely from right heart failure. When the five remaining shock-plus-pneumonectomy pigs were compared to the two control groups, pulmonary vascular resistance (PVR) increased to significantly higher levels than would be expected from the increase in PVR noted with resuscitation from shock alone and pneumonectomy alone. Right ventricular compensation maintained cardiac index in the hemorrhage-alone group and the pneumonectomy-alone group but could not maintain cardiac index in the shock-plus-pneumonectomy group, despite maximal increases in right ventricular systolic pressure, heart rate, and right ventricular end diastolic volume. These data indicated that resuscitation from shock plus pneumonectomy cannot be effectively accomplished because increased PVR leads to right ventricular failure, which limits left ventricular preload to levels that are insufficient to maintain cardiac index.

Animals↗

PubMed1991

Recruitment of lung diffusing capacity with exercise before and after pneumonectomy in dogs.

Although the left lung constitutes 42% of the total by weight and volume in dogs, carbon monoxide diffusing capacity (DL) after left pneumonectomy in adults falls less than 30% at rest, indicating a significant increase of DL in the remaining lung. DL normally increases during exercise, presumably by recruitment of alveolar capillaries and surface area as lung volume (Vs) and pulmonary blood flow (Qc) increase. We asked whether the increase of DL in the remaining lung after pneumonectomy in adult dogs could be explained by this kind of passive recruitment by the increased volume and Qc in the remaining lung. We measured the relationship between DL and Qc with a rebreathing technique at increasing treadmill loads in adult foxhounds, before and 6 mo after left pneumonectomy, and the relationship between DL and Vs by the same technique under anesthesia as Vs was expanded. DL was reduced by 29.1% at rest and 26.5% with heavy exercise after left pneumonectomy, indicating either recruitment or new growth in the right lung. With the assumption that the right lung normally receives 58% of the Qc and contains 58% of the DL, DL of the right lung increased with Qc in accordance with the following relationships before and after left pneumonectomy: right lung DL (before pneumonectomy) = 6.44 + 2.40(Qc) (r = 0.963) and right lung DL (after pneumonectomy) = 7.51 + 1.75(Qc) (r = 0.958). Only approximately 7% of the increase in DL from rest to peak exercise could be attributed to the increase in Vs during exercise before pneumonectomy and approximately 15% after pneumonectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

Recruitment of diffusing capacity with exercise in patients after pneumonectomy.

Patients after pneumonectomy are severely limited upon exercise, but impairments in gas exchange are generally mild. One potential explanation of this observation is the existence of functional reserves of diffusing capacity (DLCO), which may be recruited during exercise, predominantly by increasing pulmonary blood flow (Qc). After pneumonectomy, DLCO reserves are recruited even at rest. To investigate if the pattern of recruitment of DLCO is altered and if reserves of DLCO are exhausted during exercise after pneumonectomy, DLCO, lung volume, and cardiac output were measured by the rebreathing method at rest and at multiple levels of steady-state exercise in eight subjects after pneumonectomy and in eight age- and sex-matched nonsmoking normal subjects. In patients after pneumonectomy, the slopes of increase in DLCO [ml.(min.mm Hg)-1.m-2] with respect to QC [ml.min-1.m-2] were normal (0.91 +/- 0.09 x 10(-3) in the pneumonectomy group, 1.16 +/- 0.12 x 10(-3) in the control group, mean +/- SE, p less than 0.05). Thus, the pattern of DLCO recruitment was not significantly affected by pneumonectomy. The ratio of DLCO/Qc fell more rapidly during exercise in patients after pneumonectomy, but the lowest value of the ratio achieved was relatively normal in all except one patient. Declines in arterial O2 saturation at exercise were mild and insufficient to explain the exercise limitation except in the patient whose DLCO/Qc fell below normal. There was no evidence that an upper limit of recruitment was approached. We conclude that the normal ability to recruit DLCO during exercise after pneumonectomy constitutes an important compensatory feature that prevents significant arterial O2 desaturation. In most patients, exercise is limited by a reduced maximal stroke index before reserves of diffusing capacity are exhausted.

Adult↗

PubMed1989

[CT findings of post-pneumonectomy patients].

CT findings following pneumonectomy were studied in 28 cases with lung cancer. A total of 53 CT images were evaluated in 13 right pneumonectomy cases and 15 left pneumonectomy patients. The postpneumonectomy pleural space (PS), thoracic space of the operated site (TS) and the thoracic space of the non-operated site (CTS) were measured at 3 slice levels of the brachiocephalic level, subcarinal level and lower pulmonary vein level, using a digital planimeter. There was no significant difference in the TS/CTS ratio, between the right pneumonectomy group and the left pneumonectomy group, but the PS/TS ratio in the left pneumonectomy group was smaller than that in the right pneumonectomy group (p less than 0.01). The PS/TS ratio in both groups and the TS/CTS ratio in the right pneumonectomy group were decreased with time. In the left pneumonectomy group, the TS/CTS ratio was greater in the median sternotomy group that of the posterolateral thoracotomy group (p less than 0.01). Residual pleural effusion was accompanied with a thin circulating lesion along the outer surface. This lesion had been reported as thickening of the parietal pleura, but it could be detected in the case of panpleuropneumonectomized state. Additionally, in some cases, the parietal pleural imaging could be separated from the circulating lesion. So, this structure was thought to be mainly composed of organized effusion. CT images could detect some parts of the episodes in post operated thorax, because of the lack of the information with the sagittal direction. However, the recognition of the common changes and images on CT after the operation might be helpful for the follow-up of the patients.

Adult↗

PubMed1991

[Reevaluation of the unilateral pulmonary artery occlusion test--hemodynamics after lobectomy and pneumonectomy for lung cancer].

After lobectomy, it is recognized that functional as well as absolute reduction occurs in residual lobes of the operated side. So whether lobectomy is indicated or not is determined by the same criteria as those for pneumonectomy, namely, by the unilateral pulmonary artery occlusion (UPAO) test. However, is it really appropriate to use the same criteria for both lobectomy and pneumonectomy? To answer to this question, in patients with lung cancer we compared the hemodynamics after lobectomy (13 cases) and pneumonectomy (14 cases) with that at the UPAO test. After pneumonectomy, the mean pulmonary arterial wedge pressure (mPWP) was significantly lower than that on the preoperative day and at the test. It seemed that hypovolemic change occurred in the hemodynamics after pneumonectomy. After pneumonectomy, the pulmonary arteriolar resistance index (PARI) was significantly higher than the preoperative value. It was the same as that as at the time of the UPAO test. The total pulmonary vascular resistance index (TPVRI) at the time of the test was significantly higher than the preoperative value, but the TPVRI after pneumonectomy was not significantly higher. The TPVRI tended to decrease after pneumonectomy, compared to the value predicated by the test. These results indicated that some of the cases judged inoperable on the basis of the UPAO test might be operable. On the day of lobectomy, the PARI was significantly higher than the preoperative value, but significantly lower than that at the time of the test. The cardiac index (CI) was significantly higher and the mPWP was significantly lower than each preoperative value.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1990

Hemodynamic changes after pneumonectomy in the exercising foxhound.

Pulmonary arterial pressure is higher during exercise after pneumonectomy than before. Several factors may contribute to the elevation, e.g., loss of vascular bed, overinflation of the remaining lung, and active pulmonary vasoconstriction. We measured hemodynamic changes during graded exercise in conditioned foxhounds and compared pulmonary pressure-flow relationships before and after left pneumonectomy. Pulmonary arterial pressure-flow relationship in the remaining lung is not altered by pneumonectomy, suggesting that the increase in pulmonary vascular resistance post-pneumonectomy is largely the passive consequence of increased pulmonary blood flow to the remaining lung. The potential for chronic hyperinflation of the remaining lung to increase pulmonary resistance after pneumonectomy may have been counterbalanced by a concomitant reduction in lung elastic recoil. Unexpectedly, both mean systemic blood pressure and hematocrit were higher with respect to cardiac output after pneumonectomy. Cardiac output and stroke volume at any given work load were lower after pneumonectomy than before, and heart rate response was unaltered. This pattern of responses suggests that increases in left and right ventricular afterload may have contributed to the reduction in cardiac output.

Animals↗

PubMed1975

Lung growth after unilateral pneumonectomy: quantitation of collagen synthesis and content.

Unilateral pneumonectomy in the adult rabbit causes the mass of the remaining lung to double within one month. The content and synthesis of lung collagen were compared in 113 rabbits with pneumonectomy, thoracotomy without pneumonectomy, or pneumonectomy with subsequent wax plombage. By the twenty eighth day after left pneumonectomy, total lung collagen and cell number were nearly 100 per cent greater than matched control values, but the density of both collagen and cell number remained constant and unchanged from control. This collagen accumlation was preceded by an increase in the rate of collagen synthesis per cell and in the per cent of lung total protein synthesis represented by collagen synthesis. In normal neonatal lung growth, total lung mass, collagen, and cell number increase. During this same period there is also an increase in the per cent of collagen synthesis represented by lung total protein synthesis; however, in contrast to postpneumonectomy adult lung growth, the density of collagen increases. Obliteration of the empty hemithorax with wax after pneumonectomy resulted in suppression of the increases in right lung cell number, collagen synthesis, and collagen accumlation seen with pneumonectomy alone. This could have generalized implications relating to the control of lung gene expression in that lung cell replication and/or lung cell differentiation may, in part, be controlled by the available space into which the lung may grow.

Animals↗

PubMed1975

Regional pulmonary function before and after pneumonectomy using 133xenon.

Regional pulmonary function studies using 133xenon gas, spirometry, and arterial blood gas levels were performed before and 1 to 47 months after pneumonectomy for bronchogenic carcinoma in 27 patients. The mean loss in forced vital capacity was more after right pneumonectomy (44.9 percent of preoperative value) than after left lung resection (41.4 percent). There was no significant change in regional pulmonary function distribution within the remaining lung in 24 patients. Two patients developed significant changes in regional pulmonary blood flow; one had hepatic cirrhosis, and the other sustained a myocardial infarction after pneumonectomy. The third patient with significant apical hyperperfusion before pneumonectomy gradually developed abnormal distribution of ventilation concomitant with electrocardiographic evidence of cor pulmonale within two years after pneumonectomy. The mean ventilation of the apical zones was significantly lower than the mean of 14 healthy subjects. This finding and the higher incidence of ventilatory defects were related to old age and heavy smoking. Seven patients with marked reduction of pulmonary blood flow to the tumor-bearing lung (9 to 33 percent of cardiac output) had technically successful pneumonectomy. A formula and nomogram were developed to estimate the prognostically significant forced expiratory volume in one second after pneumonectomy from the preoperative studies.

Age Factors↗

PubMed1989

Determinants of perioperative morbidity and mortality after pneumonectomy.

A total of 197 consecutive patients undergoing pneumonectomy at the M.D. Anderson Cancer Center from 1982 to 1987 were reviewed. Sixty-five variables were analyzed for the predictive value for perioperative risk. The operative mortality rate was 7% (14/197). Patients having a right pneumonectomy (n = 95) had a higher operative mortality rate (12%) than patients having a left pneumonectomy (1%, p less than 0.05). The extent of resection correlated with the operative mortality rate (chest wall resection or extrapleural pneumonectomy, n = 39, 15%; versus simple or intrapericardial pneumonectomy, n = 158, 5%; p less than 0.05). Patients whose predicted postoperative pulmonary function, by spirometry and xenon 133 regional pulmonary function studies, was a forced expiratory volume in 1 second greater than 1.65 L, forced expiratory volume in 1 second greater than 58% of the preoperative value, forced vital capacity greater than 2.5 L, or forced vital capacity greater than 60% of the preoperative value had a lower operative mortality rate (p less than 0.05). Atrial arrhythmia was the most common postoperative complication (23%). Xenon 133 regional pulmonary function studies are useful in predicting the risks of pneumonectomy.

Aged↗

PubMed1992

Cardiopulmonary adaptations to pneumonectomy in dogs. I. Maximal exercise performance.

Maximal exercise performance was evaluated in four adult foxhounds after right pneumonectomy (removal of 58% of lung) and compared with that in seven sham-operated control dogs 6 mo after surgery. Maximal O2 uptake (ml O2.min-1.kg-1) was 142.9 +/- 1.9 in the sham group and 123.0 +/- 3.8 in the pneumonectomy group, a reduction of 14% (P less than 0.001). Maximal stroke volume (ml/kg) was 2.59 +/- 0.10 in the sham group and 1.99 +/- 0.05 in the pneumonectomy group, a reduction of 23% (P less than 0.005). Lung diffusing capacity (DL(CO)) (ml.min-1.Torr-1.kg-1) reached 2.27 +/- 0.08 in the combined lungs of the sham group and 1.67 +/- 0.07 in the remaining lung of the pneumonectomy group (P less than 0.001). In the pneumonectomy group, DL(CO) of the left lung was 76% greater than that in the left lung of controls. Blood lactate concentration and hematocrit were significantly higher at exercise in the pneumonectomy group. We conclude that, in dogs after resection of 58% of lung, O2 uptake, cardiac output, stroke volume, and DL(CO) at maximal exercise were restricted. However, the magnitude of overall impairment was surprisingly small, indicating a remarkable ability to compensate for the loss of one lung. This compensation was achieved through the recruitment of reserves in DL(CO) in the remaining lung, the development of exercise-induced polycythemia, and the maintenance of a relatively large stroke volume in the face of an increased pulmonary vascular resistance.

Animals↗

PubMed1979

Normal lung growth and response after pneumonectomy in rats at various ages.

Lung growth was accompanied by alveolar multiplication in rats from 4 to 10 wk of age; the multiplication then ceased until 14 wk of age, and in this latter interval the alveolar walls appeared to lengthen. The relationship between size of surface alveoli and size of internal alveoli of the lower lobe changed with age, and the relationship was not altered by pneumonectomy. The surface alveoli were smaller than internal alveoli at 4 wk of age, the same size at 6 and 10 wk of age, and larger at 14 wk of age. Four-week-old rats responded to pneumonectomy with an increase in size of the contralateral lung and an increase in the number of alveoli. Direct alveolar counts did not show a significant increase in number of alveoli after pneumonectomy in 8- and 12-wk-old rats. the alveolar surface area incresed almost directly with the increase in gas-exchanging lung volume in 8-wk-old rats, suggesting that alveolar multiplication might have occurred. In 12-wk-old rats, however, the alveolar surface area increased to the 0.71 power of the increase in gas-exchanging lung volume, suggesting that alveolar enlargement, rather than alveolar multiplication, had occurred. Taken in conjunction with the data for growth in normal and sham-operated animals, these results suggest that compensatory alveolar multiplication is part of the adaptive response to pneumonectomy when this operation is performed at a time at which alveolar multiplication normally occurs. When pneumonectomy is performed after alveolar multiplication has ceased, the adaptive response is primarily one of air-space enlargement. Lung volume, weight, surface area, and protein responses to pneumonectomy were smaller at 12 wek of age than at 4 and 8 wk of age.

Adaptation, Physiological↗

PubMedDate not supplied

Changes of growth hormone, somatomedin C, and bombesin following pneumonectomy.

Left pneumonectomy (PX) was performed on 14-day-old pregnant rats. Serum growth hormone (GH), lung somatomedin-C-like immunoreactivity (SmC), and lung bombesin-like immunoreactivity (BLI), using optimized radioimmunoassays and lung protein concentration (P), were measured 3 h, and 1, 2, 3, 5, and 7 days following pneumonectomy. These levels were compared to two groups of similar animals: sham operated animals and animals not subjected to surgery. Serum GH, lung SmC, and BLI levels were similar in the last two groups of animals, suggesting that surgery had no effect on GH, SmC, and BLI levels. These two control groups were combined and compared to the post-pneumonectomy animals. The post-pneumonectomy animals had significantly higher levels of serum GH at postoperative day 3 and significantly higher levels of SmC at days 2 and 5 without any significant difference in total BLI level and body weight. These results suggest that, first, GH and SmC may play a part in post-pneumonectomy compensatory lung growth and these two may also be interrelated in this response and, second, BLI material(s) perhaps do not play a role in post-pneumonectomy lung growth.

Animals↗

PubMed1990

[Two cases of wedge pneumonectomy in primary lung cancer involved into carina].

Right wedge pneumonectomy was performed on two cases of primary lung cancer involved into carina. A 59-year-old male involved with primary lung cancer was found with bloody sputum. Preoperative data confirmed as the superficial spread type of squamous cell carcinoma in carinal lesion and tumor was resectable with wedge pneumonectomy. In the second case, abnormal shadow was pointed out on chest X-ray film of a 61-year-old male patient. Preoperative examination defined as primary lung cancer of rt-S6 with subcarinal lymph node metastasis. The operation indicated wedge pneumonectomy with patch plasty using the wall of right main bronchus. Although wedge pneumonectomy is not common compared to sleeve pneumonectomy, if available this procedure is technically easier and post-operative management may be more successful. Wedge pneumonectomy limits resectable area, because the continuation of tracheo-bronchial wall must be remained in part. Therefore, the indication of this procedure for surgical treatment of lung cancer is limited. However, when this procedure indicates to selected case with limited lesion of carina, this may be an useful procedure as surgical treatment of primary lung cancer.

Adenocarcinoma↗

PubMed1979

The effects of early pneumonectomy on the remaining pulmonary parenchyma.

To determine the age-related response of the remaining pulmonary parenchyma to lung resection, a matched set of 24 purebred beagle dogs underwent pneumonectomy at 6 to 10 weeks of age (group I) or at 1 year of age (group II). Eight unoperated adult beagles served as controls (group III). One year after pneumonectomy, pulmonary hemodynamics in group I were the same as those in older animals shortly after pneumonectomy and in normal control animals. Functional residual capacity, total lung capacity, single breath diffusing capacity for carbon monoxide, and static lung compliance were measured in all three groups while anesthetized and intubated. Lung volumes and diffusion capacity for carbon monoxide in group I did not differ significantly from those of control animals. Group I animals did have a lower lung compliance than the control group, but significantly greater than the group II adult pneumonectomy dogs. The adult pneumonectomy dogs (group II) had significantly lower values for lung volumes, diffusion capacity, and compliance when compared to the control group. Arterial blood gases were not significantly different among the groups. It is concluded that beagles undergoing early pneumonectomy have an increase of alveoli beyond the normal complement in the remaining lung with concomitant remodeling of the pulmonary capillary bed resulting in normal lung volumes, diffusing capacity, and gas exchange.

Age Factors↗

PubMed1989

The response of the pulmonary circulation to exercise during normoxia and hypoxia following pneumonectomy in the adult sheep.

Pneumonectomy approximately halves the available pulmonary vascular bed. It is unknown whether the remaining lung has sufficient vascular reserve to cope with increased blood flow under stressful conditions without demonstrating abnormal pulmonary hemodynamics. To investigate this question, unanesthetized ewes with vascular catheters had hemodynamics assessed before and after a left pneumonectomy. Subsequently, on different days, the sheep were exercised on a treadmill under normoxic and hypobaric hypoxic (430 mmHg) (1 mmHg = 133.3 Pa) conditions. Pneumonectomy itself increased mean pulmonary arterial pressure by 4 mmHg. During normoxic or hypoxic exercise, the pneumonectomized sheep demonstrated a pulmonary hemodynamic response similar to normal sheep with two lungs. The pressure-flow relation for the right lung suggested the vascular reserve of the lung was not exceeded during exercise in the pneumonectomized sheep. Eighteen to 70 days after pneumonectomy there was no evidence of right ventricular hypertrophy, but there were small increases in the number of muscularized vessels less than 50 microns diameter and in the amount of muscle in normally muscularized pulmonary arteries. This study demonstrates that pneumonectomy slightly increases mean pulmonary arterial pressure. However, there is sufficient vascular reserve in the remaining lung to permit a normal hemodynamic response to exercise-induced increased blood flow even under hypoxic conditions.

Animals↗

PubMed1985

Lung growth in response to unilateral pneumonectomy in rapidly growing rats.

The rapidity with which lung growth is initiated and completed after pneumonectomy was examined in young rats (4 wk of age; 82 g). After left pneumonectomy, the remaining lobes of the right lung grew to equal the weight of both lungs of control animals by day 7 and within 14 days increased from 366 to 968 mg. The tissue concentrations of RNA, DNA phosphate, collagen, and noncollagen proteins did not increase during the growth response. In contrast, total amounts of these constituents increased significantly in the remaining lung of pneumonectomized animals during the 1st postoperative wk and approached levels found in both lungs of sham-operated and unoperated controls by the end of the 2nd wk after pneumonectomy. Although cell size increased in control lungs during the experimental period, there was little evidence of additional cellular hypertrophy associated with compensatory lung growth. The character of the response to pneumonectomy in these rats was similar to that observed previously in older animals (320 g). Thus in spite of the higher basal rate of lung growth in the younger rats, the pattern and rapidity of compensation after pneumonectomy was similar in both age groups.

Animals↗

PubMed1990

Gas exchange abnormalities after pneumonectomy in conditioned foxhounds.

Loss of a major portion of lung tissue has been associated with impaired exercise capacity, but the underlying mechanisms are not well defined. We studied the alterations in gas exchange during exercise before and after left pneumonectomy in three conditioned foxhounds. After pneumonectomy, minute ventilation and O2 consumption at comparable submaximal work loads were unchanged but arterial PCO2 at any work load was higher, implying that ventilatory response to CO2 was impaired. Arterial hypoxemia and an elevated alveolar-arterial O2 tension difference (AaDO2) developed during heavy exercise. Using the multiple inert gas elimination technique, we determined the distributions of ventilation-perfusion (VA/Q) ratios postpneumonectomy. Significant increase in VA/Q inequality developed during exercise while the foxhounds were breathing room air, accounting for an average of 42% of the total increase in AaDO2 while diffusion limitation accounted for 58%. While the animals were breathing hypoxic gas mixture, diffusion limitation accounted for an average of 88% of the total increase AaDO2. Cardiac output and O2 delivery were reduced at a given O2 consumption after pneumonectomy. After pneumonectomy, the animals reached O2 consumptions close to the maximum expected for normal dogs. Compensation for the impairment in O2 delivery post-pneumonectomy occurred mainly by an increase in hemoglobin concentration. Training probably played an important role in returning exercise capacity toward prepneumonectomy levels. We conclude that significant abnormalities in gas exchange develop during exercise after loss of 42% of lung tissue, but the animals demonstrate a remarkable ability to compensate for these changes.

Animals↗