Pulmonary function in commercial glass blowers.

This study examined the pulmonary function of 87 male commercial glass factory workers. Statistical analysis of the data indicated that workers with full-time glass blowing job descriptions had significantly higher percent predicted values for FVC, FEV1 and significantly higher maximal inspiratory and expiratory muscle pressures than their cohorts with minimal or nonglass blowing job descriptions. The results of this study indicate that persons using their respiratory muscles as full-time blowers to manufacture commercial blown glass products have significantly greater lung function values than part-time blowers or their nonglass blowing co-workers.

Cardiopulmonary regulation after rapid-eye-movement sleep deprivation.

Arterial blood pressure, chest movement, electroencephalogram, and electromyogram were monitored in six normotensive Sprague-Dawley rats for 4 h/day 3 days before and 4 days after 114 h of rapid-eye-movement (REM) sleep deprivation. During recovery sleep immediately after REM sleep deprivation (RD), there was a significant increase in the amount of time spent in REM sleep. During this rebound in REM sleep, there was a significant rise (26%) in heart rate in wakefulness, non-REM sleep, and REM sleep during the first 4 h after RD. Systolic blood pressure was also significantly elevated (14%) but only during wakefulness before recovery sleep. Rats with the greatest waking systolic blood pressure after RD had the lowest REM sleep rebound in the 4 h immediately after RD (r = -0.885, P less than 0.05). The rise in heart rate, systolic blood pressure, and REM sleep time evident on day 1 immediately after RD was absent on recovery days 2-4. The respiratory rate tended to be higher throughout the recovery period in every state of consciousness; however, these values never reached the level of significance. In the initial recovery sleep period, regulation of heart rate was more disrupted by REM sleep deprivation than either arterial blood pressure or respiratory rate.

Effect of chronic intracerebroventricular infusion of cholecystokinin on respiration and sleep.

We investigated the effect of chronic intracerebroventricular infusion of the sulfated cholecystokinin octapeptide (CCK-8S) on sleep pattern and respiratory rate. The results indicate a depression of respiratory rate during Non-REM and REM sleep as well as an increase in the number of REM periods occurring per hour of Non-REM sleep. It is suggested that central release of CCK-8S is capable of modulating the automatic regulation of respiration during sleep and altering the normal sleep-waking pattern.

Effect of burn wound bacterial colonization on sleep and respiratory pattern.

This study examined the effect of bacterial colonization of a burn wound on the sleep pattern and respiration during sleep. Sleep patterns of adult rats were monitored for one week before and two weeks after a 30 percent total body surface, full skin thickness burn with and without seeding the fresh wound with nonvirulent Pseudomonas aeruginosa. Unseeded rats were euthermic and exhibited a normal sleep pattern during the first-week post burn; however, rapid eye movement (REM) sleep percent was significantly decreased by the second week due to a reduction in the frequency rather than duration of REM periods. Rats with seeded wounds were febrile and had a significantly lower REM sleep percent throughout the two-weeks post burn due to a reduction in frequency but not duration of REM periods. The increase in respiratory rate from the non-REM to REM sleep state observed before injury was abolished in the seeded group post burn. There was an immediate but transient 24 h drop in REM sleep following thermal injury. Bacterial colonization of the burn wound by either immediate, artificial seeding or by delayed, spontaneous means significantly decreased REM sleep with and without fever, respectively. These results indicate that noninvasive bacterial colonization of a burn wound was capable of decreasing REM sleep without causing fever and that REM sleep reduction was a more sensitive indicator of the extent of burn wound bacterial colonization than was colonic temperature.

p-Chloroamphetamine: effect on sleep and respiration in the rat.

Rats, fitted with chronic EEG and EMG electrodes and a thoracic pneumograph, were monitored electrophysiologically for three successive days before and after an IP injection of p-chloroamphetamine (PCA) (2 mg/kg). During the 12 hours post PCA treatment, sleep onset was delayed, the percentage of Rapid Eye Movement (REM) sleep was decreased and the breathing rate during both the Non-REM (NREM) and REM sleep states was reduced. By 24 and 48 hours after the PCA injection, the sleep pattern and NREM respiratory rate had returned to control values; however, respiratory rate during REM sleep still tended to be decreased. The results suggest that PCA, at this dose, is capable of inducing insomnia and reducing REM sleep acutely without chronically altering the sleep pattern. The data also suggest that respiratory rate during sleep may decrease following PCA treatment.

Partial airway occlusion during sleep and waking in the dog.

Airflow was impeded for four consecutive hours in nine adult dogs in order to ascertain whether the sleeping pattern would be altered and whether the respiratory responses would differ according to the stage of sleep or waking. Partial airway occlusion (PAO) was induced by reducing the diameter of a tracheostomy tube by an average of 58% (i.e. to a final airway diameter of ca 3mm). This had the effect, during sleep, of significantly decreasing the respiratory rate by 21%, decreasing the minute volume by 31% and increasing PACO2 by 5 Torr (0.67 kPa) as compared to sleep in which respiration was unimpeded. There appeared to be no difference between REM sleep and Non-REM sleep in terms of the respiratory responses to the imposed stress. In the case of the waking state, the PAO did not elicit any statistically significant alteration of the respiratory parameters although there was a suggestion that the direction of change for each parameter was the same as in sleep. While respiration during sleep was unquestionably affected when the dogs were required to breathe through a plug with a very narrow opening, the gross sleep pattern remained unchanged.