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N Boisseau

Publications and source records attributed to N Boisseau.

12 recordsLinked to original sources
PubMed2003

[Assessment of 44 heat and moisture exchange filters. What to choose?].

OBJECTIVES: If the use of heat and moisture exchange filter (HMEF) in anaesthesia is recommended by the French Society of Anaesthesia and Intensive Care (SFAR), the criteria's choice are not clearly defined. Many HMEF are proposed by manufacturers which technical characteristics are different. STUDY DESIGN: The aim of this study was to evaluate the HMEF using items of the American Association of Respiratory Care (AARC) and technical dossiers. METHODS: All manufactures producing filters have been contacted to give their technical dossiers. Forty-eight filters have been analyzed (13 mechanical filters, 31 electrostatic filters). Each item has been scaled 0, 5 or 10. The final result was on 10. RESULTS: Seventeen filters had a note superior to 5. There were 8 mechanical filters and 9 electrostatic filters. The difference between the filters was the size of the micro-organisms tested and the duration of the test. Some filters were not tested by independent laboratories (N = 8). There were differences between the commercial documentation and on Internet and the technical dossiers (N = 12). DISCUSSION: We noted the good quality of the filters particularly concerning criters recommended by the Sfar (filter medium, filtration efficiency, microbial challenge number and duration of the test). The electrostatic filters recently used in anaesthesia have high performance concerning filtration efficiency. To supprime the moisture output criteria did not change the results. CONCLUSIONS: Criteria's used by manufactures to evaluate there filters are not always precised or too restrictive. The technical tests, the international norms, the certificates of validation, the ergonomic qualities and the definition of our needs are the main elements of choice of a filter.

Anesthesiology↗
PubMed2003

Clonidine premedication improves metabolic control in type 2 diabetic patients during ophthalmic surgery.

BACKGROUND: In stressful conditions, increasing blood glucose concentrations are closely related to an increase in catecholamines and cortisol release. Clonidine, a centrally acting alpha(2)-adrenoceptor agonist, has neuroendocrine effects, including inhibition of sympathoadrenal activity. We therefore evaluated the effect of clonidine on blood glucose control and insulin requirements during ophthalmic surgery when given as premedication in type 2 diabetic patients. METHODS: After randomization, patients were premedicated with clonidine or flunitrazepam (control). Patients were given insulin by continuous i.v. infusion to maintain blood glucose in the range 5.5-11.1 mmol litre(-1). Blood glucose concentrations were measured every 15 min during surgery, and hourly for 6 h after surgery. Plasma C-peptide and counter-regulatory hormones were also measured. RESULTS: Glycaemia was significantly lower in the clonidine group (P<0.01) and the median amount of insulin administered was significantly reduced: clonidine group 9.0 (interquartile range 5.1) units; control 18.6 (10.2) units; P<0.01). Plasma catecholamine concentrations were lower in patients given clonidine (P<0.05) but there was no difference in cortisol concentrations. CONCLUSION: Premedication of type 2 diabetic patients with clonidine 90 min before surgery improves blood glucose control and decreases insulin requirements during ophthalmic surgery.

Aged↗
PubMed2002

Protein intake and nitrogen balance in male non-active adolescents and soccer players.

Recommendations for the requirements for protein intake amount usually to 0.8-1.0 g x kg(-1) body mass x day(-1) in adolescents without any reference to the undertaking of acute exercise or to the training status. The present investigation intended to determine the nitrogen balance and protein intake in 8 healthy male non-active adolescents and 11 adolescent soccer players, both groups aged about 15 years. An assessment of nutrient intake was obtained by analysing 7 day food records collected by a questionnaire. Nitrogen excretion rate was determined and nitrogen balance was calculated from the mean daily protein intake and the urinary excretion. The results showed that the nutritional status of the two groups was similar. Nevertheless, we found that their diets were quite inappropriate in terms of the intakes of carbohydrate, some minerals (zinc, calcium, magnesium), vitamins (A, B6, D) and fibre. A positive nitrogen balance was observed from a mean protein intake of 1.57 g x kg(-1) body mass x day(-1) in these adolescents, whether they were non-active or athletes. Thus, the present investigation indicated that the growth and development in non-active adolescents and in adolescent soccer-players give rise to a need for a higher protein intake than is usually recommended. However, the higher protein requirements did not seem to be related only to the increased energy expenditure imposed by the exercise training in the soccer-player group.

Adolescent↗
PubMed2002

[Severe metabolic alkalosis and beer drinking].

We describe a case report with moderately low plasma sodium level and predominant metabolic alkalosis. Others have reported acid-base balance disorders, although no clear pathophysiological explanation has been put forward. We hypothesize that, combine with poor protein intake, mild hyperosmolar beer leads to a water intoxication syndrome, whereas strong hyperosmolar beer intake more likely induces hypochloremic metabolic alkalosis.

Adult↗
PubMed2002

Comparison of the effects of sevoflurane and propofol on cortical somatosensory evoked potentials.

BACKGROUND: Propofol (P) and sevoflurane (S) are potential anaesthetic agents if electrophysiological monitoring is required during spinal surgery. They allow rapid recovery and do not depress cortical somatosensory evoked potentials (SSEP) as much as other agents. The effects of these agents on SSEP have not been compared before. METHODS: Twenty-four patients were allocated randomly to receive either S (n = 12) or P (n = 12). SSEP evoked by electrical stimulation of the posterior tibial nerve at the ankle were recorded before anaesthesia. The cortical potential P40 was recorded (latency P40 and amplitudes N29P40 and P40N50). The anaesthetic concentration was adjusted gradually to obtain three predetermined ranges of values of bispectral index (BIS): 45-55, 35-45 and 25-35. For each range, a stable state was maintained for 10 min and SSEP were recorded. RESULTS: For the BIS 45-55 range, compared with preoperative values, P40 latency increased during S [mean change +2 (SD 0.6) ms] but not during P [+0.4 (0.2) ms (P = 0.12)] and both amplitudes (N29P40 and P40N50) decreased with S. Increasing S concentration caused a dose-dependent depression of SSEP. P did not have a statistically significant effect on the recordings and the signals remained stable in each BIS range. CONCLUSION: Sevoflurane affected SSEP recordings in a dose-dependent fashion. Propofol had a minimal effect on SSEP recordings.

Adult↗
PubMed2002

Tapia's syndrome following shoulder surgery.

Multiple cranial palsy occurred after shoulder surgery in the sitting position. Compression by the tracheal tube, caused by displacement of the head, may have caused the injury.

Adult↗
PubMed2001

Improvement of 'dynamic analgesia' does not decrease atelectasis after thoracotomy.

There is still controversy concerning the beneficial aspects of 'dynamic analgesia' (i.e. pain while coughing or moving) on the reduction of postoperative atelectasis. In this study, we tested the hypothesis that thoracic epidural analgesia (TEA) prevents these abnormalities as opposed to multimodal analgesia with i.v. patient controlled analgesia (i.v. PCA) after thoracotomy. Fifty-four patients undergoing thoracotomy (lung cancer) were randomly assigned to one of the two groups. Clinical respiratory characteristics, arterial blood gas, and pulmonary function tests (forced vital capacity and forced expiratory volume in 1 s) were obtained before surgery and on the next 3 postoperative days. Atelectasis was compared between the two groups by performing computed tomography (CT) scan of the chest at day 3. Postoperative respiratory function and arterial blood gas values were reduced compared with preoperative values (mean (SD) FEV1 day 0: 1.1 (0.3) litre; 1.3 (0.4) litre) but there was no significant difference between groups at any time. PCA and TEA provided a good level of analgesia at rest (VAS day 0: 21 (15/100); 8 (9/100)), but TEA was more effective for analgesia during mobilization (VAS day 0: 52 (3/100); 25 (17/100)). CT scans revealed comparable amounts of atelectasis (expressed as a percentage of total lung volume) in the TEA (7.1 (2.8)%) and in the i.v. PCA group (6.71 (3.2)%). There was no statistical difference in the number of patients presenting with at least one atelectasis of various types (lamellar, plate, segmental, lobar).

Aged↗
PubMed2001

Glucose tolerance during moderate prolonged exercise in women with oral contraceptives as compared to non-users.

BACKGROUND: The purpose of this study was to assess gluco-se tolerance during exercise in women on oral contraceptives. METHODS: To this end, we investigated the effects of glucose ingestion on glucose and hormonal responses in 7 women on oral contraceptives (OC(+); 21.3+/-1.3 yrs) and 7 normally menstruating (OC(-); 22.6+/-1.3 yrs) during an ergocycle test (30 min, 60% VO2max). Venous blood samples were withdrawn at 0, 3, 5, 10, 15 and 30 min exercise and at the 30th min postexercise. Glucose was ingested per os (0.5 g x kg(-1) b.w) between the 2nd and the 3rd min of the exercise. RESULTS: Under resting condition, plasma glucose and catecholamine concentrations were similar in both groups whereas plasma GH and insulin levels were greater in OC(+) (p<0.05). Glucose/insulin ratio (G/I), used as an indicator of insulin resistance, suggested a reduced insulin sensitivity at rest in the OC(+) (p<0.05). No significant differences were observed between OC(+) and OC(-) in plasma glucose, insulin, and catecholamine concentrations during exercise. Plasma GH values were greater in OC(+) from the 15th min of the exercise and during the recovery period (p<0.01). CONCLUSIONS: This study indicated that oral glucose ingestion at the onset of prolonged submaximal exercise induced similar glucose tolerance in women taking or not oral contraceptives.

Adult↗
PubMed2000

Effects of glucose ingestion at the onset of moderate-intensity, prolonged exercise in women as compared to men.

To test glucose tolerance during exercise, the effects of oral glucose ingestion (0.5 g x kg(-1)) on plasma glucose and hormonal responses (insulin, catecholamines) were investigated in 11 women [mean (SEM) age 21.6 (1.3) years] and 10 men [22.0 (0.3) years] during cycle ergometer exercise (30 min at 60% maximum oxygen consumption, VO(2max)). The two groups exhibited similar VO(2max) values, when expressed per kg of lean body mass. Venous blood samples (5 ml) were withdrawn immediately before the exercise, during the exercise (at 3, 5, 10, 15 and 30 min) and at the 30th min of the recovery period. Glucose was ingested orally between the 2nd and the 3rd min of the exercise. As compared to men, plasma glucose concentrations were lower in women during exercise (P < 0.05 at 3, 15 and 30 min) and at the 30th min of the recovery period (P < 0. 001), while plasma insulin concentrations were higher in women during exercise (P < 0.05 at 3, 15 and 30 min). The ratio of the area under the curve for glucose over the area under the curve for insulin was lower in women during exercise (P < 0.0002). A linear relationship between glucose and insulin concentrations was found only for women during exercise (r = 0.615, P < 0.0001). No gender difference was observed for the catecholamine concentration during exercise. In conclusion, this study postulates that an oral glucose load given at the onset of a prolonged and moderate exercise bout induced lesser plasma glucose and greater insulin concentrations in women as compared to men. These data argue in favour of a greater glucose tolerance in women during exercise.

Administration, Oral↗
PubMed2000

Metabolic and hormonal responses to exercise in children and adolescents.

UNLABELLED: Ethical and methodological factors limit the availability of data on metabolic and hormonal responses to exercise in children and adolescents. Despite this, it has been reported that young individuals show age-dependent responses to short and long term exercise when compared with adults. Adenosine triphosphate (ATP) and phosphocreatine stores are not age-dependent in children and adolescents. However, phosphorus-31 nuclear magnetic resonance spectroscopy (31PNMR) studies showed smaller reductions in intramuscular pH in children and adolescents during high intensity exercise than adults. Muscle glycogen levels at rest are less important in children, but during adolescence these reach levels observed in adults. Immaturity of anaerobic metabolism in children is a major consideration, and there are several possible reasons for this reduced glycolytic activity. There appear to be higher proportions of slow twitch (type I) fibres in the vastus lateralis part of the quadriceps in children than in untrained adults, and anaerobic glycolytic ATP rephosphorylation may be reduced in young individuals during high intensity exercise. Reduced activity of phosphofructokinase-1 and lactate dehydrogenase enzymes in prepubertal children could also explain the lower glycolytic capacity and the limited production of muscle lactate relative to adults. These observations may be related to reduced sympathetic responses to exhaustive resistance exercise in young people. In contrast, children and adolescents are well adapted to prolonged exercise of moderate intensity. Growth and maturation induce increases in muscle mass, with proliferation of mitochondria and contractile proteins. However, substrate utilisation during exercise differs between children and adults, with metabolic and hormonal adaptations being suggested. Lower respiratory exchange ratio values are often observed in young individuals during prolonged moderate exercise. Data indicate that children rely more on fat oxidation than do adults, and increased free fatty acid mobilisation. glycerol release and growth hormone increases in preadolescent children support this hypothesis. Plasma glucose responses during prolonged exercise are generally comparable in children and adults. When glucose is ingested at the beginning of moderate exercise, plasma glucose levels are higher in children than in adults, but this may be caused by decreased insulin sensitivity during the peripubertal period (as shown by glucose: insulin ratios). CONCLUSIONS: Children are better adapted to aerobic exercise because their energy expenditure appears to rely more on oxidative metabolism than is the case in adults. Glycolytic activity is age-dependent, and the relative proportion of fat utilisation during prolonged exercise appears higher in children than in adults.

Adolescent↗