Rapid shift in peak melatonin secretion associated with improved performance in short shift work schedule.

We studied the performance and adaptability of 40 nurses (median age 35 years), 20 on permanent day shift and 20 on permanent night shift with fast rotation of work and days off, matched for age, gender, and socio-familial responsibilities. For 15 days prior to the study, subjects maintained sleep logs and trained for performance tests. Questionnaires were administered to evaluate adaptability to shift work.

Relationship between maximal oxygen uptake on different ergometers, lean arm volume and strength in paraplegic subjects.

The present experiment was designed to study the importance of strength and muscle mass as factors limiting maximal oxygen uptake (VO2max) in wheelchair subjects. Thirteen paraplegic subjects [mean age 29.8 (8.

[Visual, auditory and somatosensory potentials in the diagnosis of vitamin B12 deficiency].

We describe visual, brain stem auditory, and somatosensory evoked (VEP, BAEP, SEP) in a 49-year old male patient presenting with subacute degeneration of the spinal cord due to vitamin B12 deficiency. Neurological signs included tetraplegia with a C4-C5 spinal cord compression that was unchanged after surgical decompression. Before treatment, the duration of the bilateral VEP was slightly increased, though their amplitude and morphology were not modified.

Long-term effects of nasal intermittent positive-pressure ventilation on pulmonary function and sleep architecture in patients with neuromuscular diseases.

Study Objective: This article evaluates the long-term clinical and physiologic effects of nocturnal nasal intermittent positive-pressure ventilation (NIPPV) in patients with neuromuscular disease.

Methods: Before and after 18 +/- 2 months of NIPPV, we measured during the daytime arterial blood gases, lung mechanics, and respiratory muscle strength in 8 patients (51 +/- 5 years; mean +/- SEM). Sleep parameters were also evaluated at 10 +/- 2 months.

Rapid shift in sleep time and acrophase of melatonin secretion in short shift work schedule.

Tolerance to shift work and adaptability to shifting schedules is an issue of growing importance in industrialized society. We studied 40 registered nurses, 20 on fixed day-shifts and 20 on fixed night-shifts, to assess whether workers with rapidly shifting schedules were able to adapt their melatonin secretion and sleep-wake cycles. The day-shift worked 5 days with 2 days off and the night-shift worked 3 nights with 2 off.

Sleep-related respiratory disturbances in patients with Duchenne muscular dystrophy.

Sleep-related respiratory disturbances (SRD) in patients with muscle diseases may have significant clinical implications, because the patients frequently die at night. The aims of the study were to :1) assess the presence and severity of sleep-related respiratory disturbances in patients with Duchenne muscular distrophy (DMD); and 2) investigate the relationship of sleep-related respiratory disturbances to daytime symptoms and pulmonary function. We studied six clinically stable patients with Duchenne muscular dystrophy, mean age (+/- SD) 18 +/- 2 yrs.

[Value of somatosensory evoked potentials in spinal surgery monitoring in children and adolescents: 110 cases].

This study shows the results obtained in 110 patients, children and adolescents by monitoring somatosensory evoked potentials during spinal surgery: Cotrel-Dubousset instrumention, surgical anterior correction by plating, spondylolisthesis and hemivertebra surgery. The recordings were made in preoperative, peroperative and postoperative period; the anaesthetic and electrophysiological conditions allowed us to obtain reliable recordings. In the peroperative period, the recordings were made: after induction of anesthesia and exposure of the spine, after instrumentation, after maximum traction and at the end of the operation.

Breathing disorders during sleep in myasthenia gravis.

Twenty consecutive patients (16 women and 4 men), with a mean age of 40 years, who were diagnosed and treated for myasthenia gravis were enrolled in a prospective investigation aimed at determining the amount of respiratory disturbance occurring during sleep while they received treatment. Patients were clinically evaluated to determine body mass index, presence of upper airway anatomical abnormalities, level of functional capacity and activity scored from 1 to 5, and presence of sleep-related complaints. They underwent daytime pulmonary function tests, determination of maximal static inspiratory pressure, measurement of transdiaphragmatic pressure, and measurement of arterial blood gas levels.

[Contribution of somatosensory evoked potentials in the surveillance of the spinal cord during spinal surgery].

This study shows the results obtained in 51 patients, children and adolescents by monitoring somatosensory evoked potentials during spinal surgery: Cotrel-Dubousset instrumentation, surgical anterior correction by plating, spondylolisthesis and hemivertebra surgery. The recordings were made in preoperative, peroperative and postoperative periods; the electro-physiological and anaesthetic conditions allowed us to obtain reliable recordings. Analysis of the peroperative somatosensory evoked potentials showed significant differences in latencies, but also in amplitudes and morphology during distraction in scoliosis or spondylolisthesis.

Adult maltase acid deficiency myopathy: treatment with long-term home mechanical ventilation.

We report a study of an adult with a maltase acid deficiency myopathy. A restrictive respiratory syndrome due to respiratory muscle weakness is associated with paralysis of other muscular groups. In 1982 the patient presented with an alveolar hypoventilation, and mechanical ventilation was required after acute respiratory failure.

Lung transfer factor for CO at rest in normal children by a steady-state method.

Lung transfer for CO (TLCO) was measured at rest in 94 normal children (47 boys and 47 girls) whose ages ranged from 3.5 to 16 years. A steady-state method, using a technique of alveolar sampling based on the equality of the mean expiratory and alveolar respiratory quotients, was employed.

[Routine bedside measurement of arterio-alveolar CO2 difference (author's transl)].

Deficiencies in pulmonary circulation can economically be demonstrated at the patient's bedside by measuring the difference in CO2 between arterial blood and alveolar air, which reflects the air flow in non-perfused ventilated lung areas. The method does not inform on the cause of the deficiency, but normal values (i.e.

[Interest of helium-oxygen flow volume and isoflow volume curves in chronic obstructive lung disease (author's transl)].

We have compared changes in maximal flows induced by breathing gases of different density in 54 patients suffering from emphysema and chronic bronchitis. We considered as positive responders those subjects displaying an increase by at least 20% of maximal expiratory flows while breathing gases of lower density. Such a response was demonstrated in 21 cases, the remainder (33 cases) being non-responders.

[Study upon oxygen conveyance in severe anaemia. About a very serious case of hemolytic anaemia which led to a myocardial infarct (author's transl].

To understand the orientation the metabolism of a sick person whose arterial content in oxygen had collapsed (CaO2 reaching 1,9 vol/100 ml) the cardiac output and the rate myocardic extraction of the lactates have been measured. The cardiac index was very high 7,4 l/m/m2 and in spite of a low D (a-v) (2,5 vol/ml) the consumption of oxygen was normal. Three days after a first measure the steep (or brutal) fall of the cardiac and the reversal of the rate of myocardic extraction of lactate led up to diagnose an acute coronary insufficiency.

[Study of pulmonary leucostasis by measurement of the alveolo-arterial CO2 difference (author's transl)].

In order to study pulmonary leucostasis in 18 leukemic subjects, the ventilatory flow from ventilated nonperfused zones (VFVNZ) was measured using alveolo-arterial CO2 difference (28 times). This method proved to be simple and accurate in the follow-up of the patients. The number of white cells necessary to increase the VFVNZ by 1% is very different from one histologic type to another.

[Arterio-alveolar difference in CO2 (AaDCO2) : measurement, interpretation, clinical value].

The measurement of arterio-alveolar difference in CO2, easily performed, gives the percentage of non perfused ventilated pulmonary zones. The clinical value of this examination is illustrated by two observations. Its situation, among other tests of the respiratory function, is questioned particularly when the diagnosis of pulmonary embolism is concerned.

[Respiratory function at rest in obese children (author's transl)].

Abnormalities of the respiratory function are a common finding in adult obesity. In order to investigate the occurrence of similar facts in pediatric age, a group of 39 obese children (20 girls and 19 boys, aged from 7 to 15 years) whose weight excess for their height ranged from 25 to 105 p. 100 was studied and compared to a control group of normal children of similar ages.