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Biomedical subjects

N Noviski

Publications and source records attributed to N Noviski.

At least 19 recordsLinked to original sources
PubMed2004

Inhaled nitric oxide in neurogenic cardiopulmonary dysfunction: implications for organ donation.

UNLABELLED: Many cadaveric organs for transplantation come from patients dying of sudden intracranial catastrophes. Cardiopulmonary dysfunction after such neurogenic insults is a well-recognized entity. The pulmonary dysfunction usually presents as florid pulmonary edema within minutes to hours after the initial intracranial insult and may occur in isolation or co-exist with overt or subclinical myocardial dysfunction. This may result in severe hypoxia, which threatens survival and outcomes in salvageable cases and organ preservation in patients who would be potential organ donors. Thus, rapid initiation of strategies aimed at ameliorating hypoxia after an acute neurogenic insult is paramount. Strategies aimed at improving acute hypoxia include maximizing ventilator support, diuretics, and volume resuscitation. Cardiac dysfunction may require use of ionotropes. We report the case of a 16-year-old female who developed catastrophic acute posterior fossa intracranial bleeding with resulting intractable hypoxia due to neurogenic cardiopulmonary dysfunction that responded dramatically to inhaled nitric oxide (INO). The patient went on to successfully donate organs following a non-heart-beating donor protocol. This therapy, to our knowledge, has never been described previously for use in patients with hypoxia secondary to neurogenic cardiopulmonary dysfunction. CONCLUSIONS: We document for the first time a dramatic response of hypoxia to INO in neurogenic cardiopulmonary dysfunction. This therapy ameliorates hypoxia, which may have vital implications in minimizing secondary brain injury in salvageable cases and optimizing organ preservation in potential organ donors with catastrophic intracranial insults.

Administration, Inhalation↗
PubMed2001

Management of oxygenation in pediatric acute hypoxemic respiratory failure.

The prognosis for patients with acute respiratory distress syndrome (ARDS) in adults and children has improved since its formal acceptance as a clinical entity in 1967. Because acute hypoxemic respiratory failure is the hallmark of acute lung injury and ARDS, the management of oxygenation is crucial. Physicians managing pediatric patients with acute lung injury or ARDS are faced with a complex array of options influencing oxygenation. Certain treatment strategies can influence clinical outcomes, such as a lung-protective ventilation strategy that specifies a low tidal volume (6 mL/kg) and a plateau pressure limit (30 cm H(2)O) (Acute Respiratory Distress Network, N Engl J Med 2000;342:1301-1308). Other lung-protective strategies such as different levels of positive end-expiratory pressure, altered inspiratory:expiratory ratios, recruitment maneuvers, prone positioning, and extraneous gases or drugs may impact clinical outcomes but require further clinical study. This paper reviews state-of-the-art strategies on the management of oxygenation in acute hypoxemic respiratory failure and attempts to guide pediatric pulmonologists in managing children with respiratory failure.

Acute Disease↗
PubMed2000

Efficacy and safety of methacholine bronchial challenge performed by auscultation in young asthmatic children.

The measurement of bronchial reactivity is an important aid in the diagnosis of asthma, but the technique using spirometry is not feasible in young children. The aim of the present study was to determine the efficacy and safety of a modification of the chest auscultation method in the assessment of bronchial reactivity to inhaled methacholine in young asthmatic children. One hundred forty-six young children with asthma (mean age, 4.3 yr) underwent bronchial challenges with nebulized methacholine using the auscultation method (PCW). The end point was defined as the appearance of wheezing, oxygen desaturation, or tachypnea. For comparison, 30 children and young adults with asthma underwent bronchial provocation with methacholine using spirometry (PC(20)). A positive response using the auscultation method was observed in 95.9% of the younger children, and wheezes alone or in combination with other signs appeared in 80.8% of them. The mean desaturation at the end point was 4.6% (PCW) and 5.0% (PC(20)), with a similar pattern in the two groups. Cough was not helpful in determining the end point. We conclude that the modified auscultation method is effective and safe, with wheeze appearing at the end point in the large majority of the children.

Adolescent↗
PubMed2000

Arginine, citrulline, and nitric oxide metabolism in end-stage renal disease patients.

The kidneys are thought to be a major site of net de novo arginine synthesis, but the quantitative status of arginine metabolism and its substrate precursor relationship to nitric oxide (NO) synthesis in end stage renal disease (ESRD) patients have not been characterized. We have investigated kinetic aspects of whole body arginine metabolism in six patients with ESRD. They received two pre- and two post-hemodialysis intravenous tracer infusion studies with L-[guanidino-(15)N(2)]arginine and L-[(13)C]leucine during the first study, and L-[5-(13)C]arginine and L-[5-(13)C-ureido,5,5, (2)H(2)]citrulline during the second study. Arginine homeostasis in ESRD patients was found to be associated with a lower rate of arginine oxidation, and despite the decrease in renal function, the rate of de novo arginine synthesis appeared to be preserved. Plasma citrulline concentrations and flux were also elevated in these subjects compared with healthy adults. The rate of whole body NO synthesis was increased in the ESRD patients, but apparently not different pre- and post-hemodialysis therapy. The anatomic site(s) responsible for the maintenance of net de novo arginine synthesis and for the elevated NO synthesis and its pathophysiological importance in ESRD remain to be established.

Adult↗
PubMed1999

Does the size of nasogastric tubes affect gastroesophageal reflux in children?

BACKGROUND: To evaluate the effects of nasogastric tube insertion and different nasogastric tube sizes on gastroesophageal reflux in children. METHODS: During a prospective randomized study, 29 patients aged 1 month to 4 years (median, 9 months) underwent 24 hours of continuous esophageal pH monitoring to rule out gastroesophageal reflux as the cause of severe pulmonary problems. Each patient was monitored without nasogastric tube for 16 hours (baseline), and thereafter the first nasogastric tube, small (8-Fr) or large (10-Fr or 12-Fr), was placed. Four hours later, the original nasogastric tube was replaced by a new one of large (instead of small) size or of small (instead of large) size. We selected the times of wakefulness in these study periods and compared the number of reflux episodes (NREs), the number of reflux episodes that lasted more than 5 minutes (NRE>5), and the percentage of time with esophageal pH less than 4 (PTP<4). RESULTS: The 12-Fr group in comparison with the 8-Fr group and baseline showed significant difference (P<0.05) in the NRE>5 and PTP<4 parameters. No significant differences were found when comparing 8-Fr versus 10-Fr groups and baseline. In children with (n = 20) and without (n = 9) gastroesophageal reflux, comparison of the various reflux parameters between baseline and the different sizes of nasogastric tubes showed the same results. CONCLUSIONS: Size of the nasogastric tubes is a significant factor in predisposing the child to gastroesophageal reflux. Large nasogastric tubes interfere with the clearance of the refluxed acid from the esophagus.

Child, Preschool↗
PubMed1999

Mast cell activation is not required for induction of airway hyperresponsiveness by ozone in mice.

Exposure to ambient ozone (O3) is associated with increased exacerbations of asthma. We sought to determine whether mast cell degranulation is induced by in vivo exposure to O3 in mice and whether mast cells play an essential role in the development of pulmonary pathophysiological alterations induced by O3. For this we exposed mast cell-deficient WBB6F1-kitW/kitW-v (kitW/kitW-v) mice and the congenic normal WBB6F1 (+/+) mice to air or to 1 or 3 parts/million O3 for 4 h and studied them at different intervals from 4 to 72 h later. We found evidence of O3-induced cutaneous, as well as bronchial, mast cell degranulation. Polymorphonuclear cell influx into the pulmonary parenchyma was observed after exposure to 1 part/milllion O3 only in mice that possessed mast cells. Airway hyperresponsiveness to intravenous methacholine measured in vivo under pentobarbital anesthesia was observed in both kitW/kitW-v and +/+ mice after exposure to O3. Thus, although mast cells are activated in vivo by O3 and participate in O3-induced polymorphonuclear cell infiltration into the pulmonary parenchyma, they do not participate detectably in the development of O3-induced airway hyperresponsiveness in mice.

Animals↗
PubMed1997

Continuous avoidance measures with or without acaricide in dust mite-allergic asthmatic children.

BACKGROUND: Improvement in the quality of life in the Western world and increased time spent indoors by children have enhanced the spread of house dust mites and increased the exposure time for sensitive children. Also, exposure to house dust mites in infancy and subsequent development of childhood asthma have been clinically linked. Recently, new acaricides have been developed. OBJECTIVE: To test the efficacy of the new acaricide (esdepallethin and piperonyl butoxide--"Acardust") combined with environmental control compared with continuous house dust mite avoidance measures. METHOD: Forty-six house dust mite-allergic, asthmatic children were evaluated for 6 months in a prospective, randomized, double-blind, and placebo-controlled study. Patients were randomly allocated to active and placebo acaricide treatment combined with avoidance measures, whereas only continuous avoidance measures were taken in the third group. Symptom score, medication usage, and peak flow measurements were recorded daily. The amount of house dust mite allergen in the dust vacuumed from the bedrooms was also measured. RESULTS: Morning and evening peak expiratory flow rates and forced expiratory volume in one second remained unchanged throughout the study period. In all groups, the symptom scores improved significantly, whereas the amount of house dust mite allergen decreased significantly at the end of the trial. CONCLUSIONS: Continuous house dust mite avoidance measures have a significant positive effect on the symptomology of children with mild or moderate asthma. "Acardust" combined with continuous house dust mite avoidance measures is not more effective than continuous house dust mite avoidance measures alone in the treatment of house dust mite-allergic, asthmatic children.

Aerosols↗
PubMed1997

Nebulized wet aerosol treatment in emergency department--is it essential? Comparison with large spacer device for metered-dose inhaler.

OBJECTIVE: To determine the efficacy of a metered-dose inhaler (MDI) with a large spacer device as compared to nebulized wet aerosols in the treatment of an unselected population with severe airflow limitation. DESIGN: Randomized, double blind, placebo-controlled trial. SETTING: University Hospital Department of Emergency Medicine (DEM). PATIENTS: Fifty patients, referred to the DEM between October 1, 1994 and March 31, 1995 with a severe, acute obstructive pulmonary event. Thirteen patients were diagnosed as having COPD; 37 patients were diagnosed as having asthma. INTERVENTION AND RESULTS: Patients received either placebo MDI through a 750-mL cone-shaped spacer (Glaxo) [2 puffs] and nebulized salbutamol aerosol 0.5 mL in 1.5 mL saline solution (group 1, n=25) or salbutamol MDI and 0.5 mL saline solution in 1.5 mL saline solution administered in the same manner as above (group 2, n=25). The above treatment was repeated three times every 15 min, unless side effects appeared. Upon enrollment into the study, the FEV1 in group 1 was 0.78+/-0.7 L (mean+/-SD), 32% of predicted, and in group 2, 0.74+/-0.51 L, 29% of predicted (p=0.83). The FEV1 values after the first, second, and third interventions were as follows: in group 1, 1.18+/-0.99 L, 1.40+/-0.8, and 1.47+/-0.79, respectively, and in group 2, 1.17+/-0.99 L, 1.46+/-1.01, and 1.54+/-0.79 (p=0.83, 0.36, and 0.48, respectively). We observed no difference in spirometric measurements between the two groups at any time. CONCLUSION: Even in the setting of the unselected group of patient referrals to the DEM for episodes of severe airflow limitation, the clinical and the objective bronchodilator responses to the administration of salbutamol are independent of the method of delivery: MDI with a large spacer vs aerosol nebulization.

Aerosols↗
PubMed1996

Comparison of respiratory inductance plethysmography with thoracoabdominal compression in bronchial challenges in infants and young children.

Respiratory inductance plethysmography measuring thoracoabdominal asynchrony (TAA) has been claimed to be a useful tool for measuring changes in airway resistance in infants. In this study we evaluated the response to methacholine by thoracoabdominal compression and respiratory inductance plethysmography. Seventeen infants (mean age, 13.1 +/- 4.7 mo) with recurrent episodes of cough or wheeze underwent bronchial challenge with inhaled methacholine. Lung function was evaluated by measuring maximal expiratory flow at resting lung volume (VmaxFRC), and the degree of TAA was measured by phase angle (theta). Methacholine was inhaled for 1 min during tidal breathing using increasing doubling concentrations until a fall of at least 40% in VmaxFRC was achieved (final concentration). All infants responded to the final concentration of methacholine by a significant fall in VmaxFRC (from 31 +/- 10 to 12 +/- 5 ml/s/kg, p < 0.001). All but one infant responded to methacholine at the final concentration with a significant increase in phase angle (median theta increased from 11.7 to 31.7 degrees, p < 0.001). In two other infants there was an early response in theta compared with the response in VmaxFRC. Phase angle increase after methacholine was expressed as Z-scores (the difference between postmethacholine theta and postbuffer theta divided by the standard deviation of postbuffer theta). An increase of at least 2.0 Z-scores in theta was observed at the same concentration of methacholine when VmaxFRC fell by at least 40% in 15 of the 17 infants (88%). We conclude that respiratory inductance plethysmography is a sensitive method to measure bronchial reactivity to methacholine in most of the infants studied (14 of 17, 82%). A concentration of methacholine causing an increase in theta of at least 2.0 standard deviations above baseline is equivalent to the concentration causing a 40% fall in VmaxFRC.

Airway Resistance↗
PubMed1994

Assessment of the ability of young children to use a powder inhaler device (Turbuhaler).

The purpose of the study was to determine the age at which young asthmatic children could master the use of a new powder inhaler device (Turbuhaler). We studied 59 children with asthma between the ages of 3 and 6 years who consecutively attended the asthma clinic of the pediatric department. Efficiency of inhalation and the pharmacological effect of the terbutaline in the inhaler were measured by scores for inhalation technique and clinical response. None of the 3-year-old children used the device efficiently, but 43% of the 4-year-old, 67% of the 5-year-old, and 80% of the 6-year-old children used the inhaler correctly. Although inhaler technique was not perfect in the younger age group, 50% of the 3-year-old children demonstrated clinical improvement of asthma symptoms after inhalation. In the older age groups, 79%, 92%, and 100% of the 4, 5, and 6-year-old children demonstrated clinical improvement of asthma symptoms after inhalation. It is concluded that the new mode of dry powder delivery system (Bricanyl Turbuhaler) can be used in young asthmatic children who are 4 years of age and above.

Age Factors↗
PubMed1993

Treatment of severe steroid dependent preschool asthma with nebulised budesonide suspension.

The steroid sparing effect of nebulised budesonide suspension was assessed in a double blind placebo controlled parallel group study of 36 preschool children with severe asthma who were dependent on treatment with oral steroids. Nebulised budesonide suspension significantly reduced the requirement for treatment with oral steroids, and produced a marked improvement in overall health as scored on a visual analogue scale during the clinic visits. This study shows a significant step forward in the prophylactic treatment of asthma in children under the age of 3 years, in whom the efficacy of many other nebulised treatments has been questioned.

Asthma↗
PubMed1993

Comparison of airway resistance and total respiratory system resistance in infants.

Airway resistance (Raw) can be measured throughout the respiratory cycle by whole body plethysmography. Total resistance of the respiratory system (Rrs) can be measured from the relaxed expiration that follows end inspiratory occlusion. The purpose of this study was to compare the two methods in normal infants and in infants with airway obstruction of different types and severity. Fifteen infants with essentially normal lungs aged 24.6 +/- 18.0 (SD) wk, nine infants with congenital stridor aged 36.0 +/- 17.3 wk, and eleven wheezy infants aged 20.1 +/- 11.3 wk had simultaneous measurements of Raw and Rrs. Rrs was similar to Raw both during inspiration and expiration in the normal infants, to all expiratory Raw in those with congenital stridor, and to all inspiratory and early expiratory Raw in the wheezy infants. Raw was markedly and significantly higher than Rrs during mid and late inspiration in infants with congenital stridor and during late expiration in the wheezy infants. We conclude that Rrs is a good estimate of Raw in normal infants and of early expiratory Raw in all infants. In infants with airway obstruction, Rrs does not reveal the dynamic changes in Raw during tidal breathing, nor can it differentiate between infants with upper and lower airway obstruction.

Airway Resistance↗
PubMed1992

Role of infection in the middle lobe syndrome in asthma.

Twenty one children with asthma aged 1.0-10.5 years (mean (SD) 3.3 (2.5) years) were admitted to the hospital to evaluate pulmonary right middle lobe or lingular collapse lasting one to 12 months (mean (SD) 4.4 (3.8) months). Seven children had mild asthma and were treated with inhaled beta 2 agonists as needed. Nine had moderate asthma treated with either sodium cromoglycate or slow release theophylline. Five had severe asthma treated with inhaled steroids. Each child underwent fibreoptic bronchoscopy under local anaesthesia and a bronchoalveolar lavage. Differential cell counts of the lavage fluid revealed predominance of neutrophils in 12 patients (57%). In nine of these patients cultures grew pathogenic bacteria, mainly Haemophilus influenzae and Streptococcus pneumoniae. There was no correlation between the severity of asthma and a positive bacterial culture. There was also no correlation between the duration of the right middle lobe collapse and a positive culture. We conclude that longstanding right middle lobe collapse in asthmatic children is often associated with bacterial infection.

Asthma↗
PubMed1991

Bronchial provocation determined by breath sounds compared with lung function.

Bronchial provocation testing with methacholine was undertaken in 15 children aged 5 to 8 years with obstructive lung disease, mostly asthma (13/15). The methacholine was inhaled during two minutes of tidal breathing in increasing concentrations. After each inhalation, lung function was measured and clinical signs recorded independently by two observers unaware of each other's results. The logarithm of the concentration of methacholine which caused wheezing over the trachea correlated closely with the logarithm of the concentration of methacholine causing a 20% fall in the forced expiratory volume in one second (FEV1) but was 52% greater on average. At the end of the test there was a mean (SD) fall in FEV1 of 33.3 (7.4)% and a fall in oxygen saturation of 5.2 (3.1)%. Bronchial provocation testing by listening for wheeze over the trachea is a safe technique, which correlates with objective measures of lung function in young children.

Bronchi↗
PubMed1991

Exercise but not methacholine differentiates asthma from chronic lung disease in children.

Bronchial provocation challenges with exercise and methacholine were performed on the same day or within a short interval in 52 children with asthma, 22 with other types of chronic lung disease (including cystic fibrosis), and 19 control subjects with no evidence of chronic lung disease. There were no significant differences in the baseline lung function before the two types of challenge in the individual groups and differences between the patients with asthma and with chronic lung disease were minor. When the mean -2 SD of the methacholine response of the control group was taken as the lower limit of normal, 49/52 (94%) patients with asthma and 18/22 (82%) with chronic lung disease responded abnormally. In contrast, with the mean +2 SD of the exercise response of the control group as the upper limit of normal, 41/52 (79%) asthmatic patients responded but none of those with chronic lung disease. Thus the response to the two types of challenge helps to distinguish asthma from other types of chronic lung disease in children.

Adolescent↗
PubMed1991

Nonspecific bronchial reactivity in asthmatic children depends on severity but not on age.

Bronchial reactivity to inhaled methacholine was measured by the steady-state tidal breathing method in asthmatic children aged 1 to 17 yr. The children were divided into three clinical groups according to their minimal therapeutic requirements: mild asthma, children requiring infrequent treatment with inhaled beta-agonists (81 patients); moderate asthma, children requiring daily preventive treatment with either cromolyn sodium or slow-release theophylline (67 patients); and severe asthma, children requiring daily preventive treatment with oral or inhaled steroids (34 patients). They were also divided into three age groups: from 1 to 6 yr, tested by using bronchial provocation with tracheal auscultation (BPTA) to determine the methacholine concentration causing wheezing (PCW); and from 7 to 11 yr and 12 to 17 yr, using lung function testing to determine the concentration causing a 20% fall in FEV1 (PC20). For the whole group the mean level of bronchial reactivity to methacholine correlated inversely with the severity of bronchial asthma according to the minimal drug requirements (p less than 0.0001) and was similar over the whole age range (p less than 0.9965) for each severity grouping. In the older children the difference between moderate and severe asthma was not significant, but this may have been a result of the effect of corticosteroids in the severe group. We concluded that age has no significant effect on the methacholine response in asthmatic children over a wide age range.

Adolescent↗
PubMed1990

Serum lidocaine concentrations in children during bronchoscopy with topical anesthesia.

To evaluate the safety of topical lidocaine anesthesia in children undergoing bronchoscopy, we determined SLC in 15 children aged 3 months to 9.5 years during flexible fiberoptic bronchoscopy. A total lidocaine dose of 3.2 to 8.5 (mean +/- SEM = 5.7 +/- 0.5) mg/kg was administered to nose, larynx and bronchial tree over 9 to 45 (mean +/- SEM = 20 +/- 2.7) minutes. No complication occurred during the procedure. Peak SLC were 1-3.5 (mean +/- SEM = 2.5 +/- 0.2) micrograms/ml. The Vd beta was 1.79 +/- 0.19 L/kg, the t1/2 beta was 109 +/- 12 minutes, and the total body clearance 12.2 +/- 1.1 ml/min/kg. Peak SLC correlated well with the dose expressed as mg/kg (r = 0.59, p less than 0.025), and even better when related to body surface area (r = 0.63, p less than 0.01). Lidocaine doses up to 8.5 mg/kg proved safe and resulted in therapeutic SLC in our patients. Lidocaine dose up to 7 mg/kg appears to be safe provided that it does not exceed an upper limit of 175 mg/m2 and is gradually administered over a minimum of 15 minutes. Doses of 7-8.5 mg/kg appear to be safe when administered over longer periods.

Anesthesia, Local↗