Kyphoscoliosis and respiratory failure. A patient treated with assisted ventilation for 27 years.

A 62-year-old woman had had kyphoscoliosis since age 12 years. Respiratory failure developed at age 35 years following a respiratory infection. A tracheostomy was done and she required assisted ventilation using a respiratory (Bird). Many attempts at weaning her from the ventilator were unsuccessful. She has remained dependent on assisted ventilation for more than 27 years but has had a relatively comfortable and meaningful life. In 1983, a left pleuroscopy was done related to recurrent pneumothorax and numerous small bullae were seen on the lung surface. Recent investigation using computed tomographic scanning has shown patchy areas of emphysema in both lungs. Emphysema is not a feature of kyphoscoliosis and it is suggested that intermittent positive pressure applied to the lung over long duration may cause the lung destruction of emphysema.

Daily maintenance dose of a long-acting theophylline from a single theophylline serum level.

A single point method has recently been described whereby the daily maintenance dose of theophylline required to achieve a desired steady state serum concentration can be established from a nomogram with the aid of a single blood sample drawn after a test dose. This approach has been validated for intravenous administration and for a rapidly absorbed elixir (coefficient of absorption ka 2.3 h-1) given to children. In order to study whether this method could be applied to a slowly absorbed preparation (ka 0.44 h-1), we gave theophylline (Theo-Dur) to nine adults as a single dose and for one week. In applying a nomogram, we found that a sample taken nine hours after a test dose would more accurately predict the daily dose required to achieve a desired steady state concentration than a sample taken at six hours as has previously been recommended (error nine hours -16.8 percent to +29 percent, six hours -59.7 percent to +29.4 percent).

The respiratory effects of regular cigarette smoking in women. A five-year prospective study.

Over a five-year period a consistent habit of smoking or nonsmoking was maintained by 302 women (aged 25 to 54 years at the beginning of the study). There were 130 nonsmokers, 40 ex-smokers, and 15 light, 46 moderate, and 71 heavy smokers. Smokers without serious disability who had stopped smoking had a very low prevalence of respiratory symptoms and showed worsening of pulmonary function over the years similar to life-long non-smokers. Although there is a dose-related response to cigarettes, individual susceptibility also plays an important role in determining the respiratory effect of smoking. A range for change in ventilatory function over a five-year period in apparently healthy nonsmoking women is provided. Using this range, it is possible to identify susceptible smokers who show deterioration in ventilatory function that is more rapid than normal. Repeated spirometric studies may be useful in selecting a group at greatest risk of developing later disabling chronic obstructive pulmonary disease.

Pulmonary function in identical twins: comparison of nonsmokers and smokers.

Forty-five apparently normal pairs of identical twins were given pulmonary function tests to determine the role of genetics in bronchial susceptibility to cigarette smoke. Maximal expiratory flow at 60 per cent of total lung capacity (Vmax60) was the best discriminator of smokers from nonsmokers among pairs in which one member smoked and the other did not. The intrapair difference of Vmax60 values in pairs in which both members smoked was the same as in pairs in which both members did not smoke. These data support the view that genetic factors are important in determining the vulnerability of the airways to cigarette smoke.

Surgical treatment for pulmonary emphysema.

Three in-vivo observations stimulated interest in surgical treatment for emphysema: (a) the destructive changes are rarely generalized, (b) the central portions of the lungs are frequently less seriously affected, and (c) marginal folding produces obstructive change in the more normal lung tissue. If destroyed avascular space-occupying areas can be removed, the compressed lung tissue may be stretched to fill pleural space in a functionally effective fashion. Residual elastic tissue will them maintain patency of terminal bronchioles. Preoperatively the extent of the destructive change can be defined most accurately by pulmonary angiography, and zones of functioning capilary circulation can be identified. Forty-seven patients with multifocal space-occupying emphysematous change have been treated surgically. The postoperative mortality was 21% but worthwhile long-term improvement has been obtained in 45% of patients presenting with disabling dyspnea. In these patients, surgical treatment warrants consideration if significant space occupation accompanies the bullous disease, provided alveolar vascularization can be demonstrated in the compressed adjacent normal lung tissue. Limited resections that preserve all vascularized and potentially functioning lung tissue are preferable. It is essential that obliteration of the hemithorax be obtained promptly in view of the high incidence of postoperative complications requiring secondary operative procedures, if 'leaks' and residual spaces are allowed to persist. Postoperative care in a respiratory intensive care unit is mandatory.

A rehabilitation program for improving exercise tolerance of patients with chronic lung disease.

A Chronic Chest Disease Rehabilitation Program has been developed in the Toronto General Hospital to improve exercise tolerance in very disabled patients. The most important part of the program is physical conditioning using mainly a motor-driven treadmill. The treadmill exercise is done breathing room air or, in the case of the most disabled patients, an oxygen-enriched gas mixture. Other exercise includes riding a stationary bicycle, going up and down stairs, and turning a wheel by hand. Other aspects of the program are breathing exercises, inhalation therapy using an ultrasonic nebulizer, chest physiotherapy, and patient education. The importance of a team approach with encouragement, enthusiasm and demonstration of steady progress is emphasized.