Pulmonary complications after cardiac surgery are a leading cause of postoperative morbidity and mortality. Respiratory muscle weakness may contribute to the postoperative pulmonary abnormalities. We hypothesized that: (1) there is a decrease in inspiratory muscle strength (PImax at residual volume) and endurance (Pmpeak/PImax) following coronary artery bypass graft (CABG); (2) this weakness is associated with reduced pulmonary function tests (PFTs), impaired gas exchange, and a higher rate of pulmonary complications; and (3) prophylactic inspiratory muscle training (IMT) can prevent those changes. Eighty-four candidates for CABG, with ages ranging from 33 to 82 years, were evaluated prior to operation and randomized into two groups: 42 patients underwent IMT using a threshold trainer for 30 min/day for 2 weeks, 1 month before operation (group A); 42 patients served as a control group and underwent sham training (group B). There was a significant decrease in respiratory muscle function, PFTs, and gas exchange in the control group following CABG, whereas these parameters remained similar to those before entering the study in the training group. The differences between the groups were statistically significant. In addition 11 (26%) patients in the control group but only 2 (5%) in the training group needed postsurgical mechanical ventilation longer than 24 hours, CABGs have a significant deteriorating effect on inspiratory muscle function, PFTs, and arterial blood gases. The decrease in these parameters can be prevented by prophylactic inspiratory muscle training, which may also prevent postsurgical pulmonary complications.

Abstractimprovement in lung volumes and respiratory muscle function. Background -Morbidly obese subjects are (Thorax 1998;53:39-42) known to have impaired respiratory function and inefficient respiratory muscles. A study was undertaken to investigate the Keywords: respiratory muscle strength, respiratory muscle endurance, weight loss.influence of excessive weight loss on pulmonary and respiratory muscle function in morbidly obese individuals who underwent gastroplasty to induce weight loss.It is well established that obesity without asMethods -Twenty one obese individuals sociated disease affects respiratory function in with mean (SE) body mass index (BMI) humans, the most persistent abnormality being 41.5 (4.5) kg/m 2 without overt obstructive a restrictive respiratory impairment. [1][2][3][4] The airways disease (FEV 1 /FVC ratio >80%) most characteristic pulmonary function abwere studied before and six months after normalities in obesity are reduced expiratory vertical banded gastroplasty. Only patients reserve volume (ERV) and functional residual who had lost at least 20% of baseline BMI capacity (FRC), due to alterations in chest wall were included in the study. Standard pul-mechanics.1 5 6 Other lung volumes, as well as monary function tests and respiratory the maximal voluntary ventilation (MVV) and muscle strength and endurance were flow rates, have been variously reported as measured.normal, increased, or decreased. 7 8 The resResults -Before operation the pre-piratory muscles are inefficient in obese indominant abnormalities in respiratory dividuals 9 and the MVV, which may be affected function were significant reductions in by reduced respiratory muscle strength, was lung volumes and respiratory muscle en-also found to be low in obese patients. 10durance and, to a lesser degree, reductionsThere are few studies that deal with the in respiratory muscle strength. All para-effect of weight loss on respiratory function. meters increased towards normal values Increased vital capacity (VC), ERV, FRC, and after weight loss with significant increases total lung capacity (TLC) have all been in functional residual capacity (FRC) from described.11 12 Respiratory muscle performance 84.0 (2.2) to 91.3 (2.5)% of predicted nor-has been less frequently studied. Wadströ m mal values (mean difference 7.3, 95% con-and associates 13 found a decrease in respiratory fidence interval of difference (CI) 4.2 to muscle strength following weight reduction of 10.5), total lung capacity (TLC) from 85.6 10% after gastroplasty but several weeks later, (3.0) to 93.5 (3.7)% of predicted normal when the mean weight loss was already 18%, values (mean difference 7.9, 95% CI 4.5 to the respiratory muscle strength did not differ 11.5), residual volume (RV) from 86.7 (3.1) from baseline values. to 96.4 (3.0)% of predicted normal valuesWe have studied pulmonary function and (mean difference 9.7, 95% CI 5.2 to 14.1), respiratory muscle performance in a group of expiratory reserve volume (ERV) from obese individuals without evidence of sig-...

In patients undergoing lung resection the simple calculation of predicted postoperative FEV1 underestimates the actual postoperative FEV1 by a small fraction. Lung functions can be increased significantly when incentive spirometry and specific inspiratory muscle training are used before and after operation.

Asthma occurs more frequently in the elderly than is usually appreciated and may, therefore, be underdiagnosed and undertreated. This study evaluated the relationship between asthma symptoms and the degree of airflow obstruction in elderly and young asthmatics. Fifteen young asthmatics (<65 yrs) (group A), 15 aged >65 yrs with onset of symptoms before 65 yrs (group B), and 15 aged >65 yrs with onset of symptoms after 65 yrs (group C), were studied. Patients used daily diary cards, during 2 weeks, to record inhaled beta2-agonist consumption and severity of asthma symptoms. Long-standing asthma was associated with a significantly lower forced expiratory volume in one second as compared with recent onset asthma. The asthma-symptom score was highest in group A, lower in group B and significantly lower in group C. When symptoms were related to the degree of obstruction (asthma index), it was higher in the young asthmatics than in both groups of elderly patients. In conclusion, elderly patients with long-standing asthma had more severe airway obstruction than patients with recently acquired disease. Older patients particularly those with long-standing disease complained less about asthma symptoms. Within the various groups of patients, subjective symptoms of asthma were negatively related to asthma duration.

No abstract