Biomedical subjects

N A Hanania

Publications and source records attributed to N A Hanania.

5 recordsLinked to original sources

PubMed1996

The accuracy of a handheld portable spirometer.

BACKGROUND: Objective measurement of lung function is considered essential in the management of patients with asthma and COPD. Many primary care practitioners lack the means necessary to obtain these measurements conveniently. To meet this need, electronic spirometers, offering portability, ease of operation, and timesaving readout options have been introduced. We compared the accuracy of a typical pneumotachograph-based device with a conventional volume displacement spirometer. METHODS: We compared indexes of pulmonary function (FVC, FEV1, mean forced expiratory flow during the middle half of FVC, [FEF25-75%], and peak expiratory flow rate [PEFR]) measured by the handheld device with those measured by a conventional spirometer in 75 white subjects (33 men, 42 women) with a median age of 43 years (22 to 77 years) who were either healthy or were referred to the pulmonary function laboratory of a large tertiary care teaching hospital. The order of the instrument tested first was randomized and the patients were blinded to which instrument was being studied. RESULTS: There was a linear relationship between instruments for all indexes measured (r = 0.97, 0.98, 0.94, 0.94 for FVC, FEV1, FEF25-75%, and PEFR, respectively, for all p < 0.001). The random error (precision) was within 5% only for FEV1. The mean of the differences between the values obtained using both instruments (the bias) +/- limits of agreement (+/- 2 SD) were 0.06 +/- 0.56 L for FVC (p = NS), 0.2 +/- 0.44 L for FEV1 (p < 0.05), 0.61 +/- 1.26 L/s for FEF25-75% (p < 0.05), and 0.44 +/- 1.9 L/s for PEFR (p < 0.05). CONCLUSION: Our data suggest that measurements obtained using the pneumotachograph device are closely related to those obtained by volume displacement spirometry and that the handheld device may be useful in clinical practice. However, because the limits of agreement are wide and the difference between the two instrument measurements are significant for FEV1, FEF25-75%, and PEFR, the bias between them is not consistent nor is it insignificant. Therefore, the measurements made with the two types of machine cannot be used interchangeably.

Adult↗

PubMed1995

Adverse effects of inhaled corticosteroids.

Inhaled corticosteroids are considered by many to be the anti-inflammatory therapy of choice in adult asthma, given their remarkable efficacy and apparent safety. They are presently being prescribed to more patients, at larger doses, and for longer periods of time than ever before. Oropharyngeal candidiasis and dysphonia are the most commonly recognized adverse effects of therapy, but these topical phenomena cause no significant morbidity and are easily managed. By contrast, there is now increasing concern about the potential systemic effects of inhaled corticosteroids. These putative effects may include adrenal suppression, bone loss, skin thinning, increased cataract formation, decreased linear growth in children, metabolic changes, and behavioral abnormalities. Changes in adrenal function have been noted in patients using medications such as beclomethasone dipropionate and budesonide in doses exceeding 1,500 micrograms/day. The clinical relevance of these changes has yet to be clarified. Several short-term and cross-sectional studies have also revealed changes in biochemical markers of bone turnover and retrospective studies have found reduced bone density in asthmatics treated regularly with inhaled steroids. Long-term prospective studies assessing bone density changes remain to be done. Although much controversy exists, there is no unequivocal evidence that conventional doses of inhaled steroids significantly retard bone growth in children. Reports on skin changes, increased cataract formation, and behavioral changes are difficult to interpret because of several confounding factors. Although inhaled steroids should, at the present time, continue to be a recommended therapeutic option to all patients with symptomatic asthma, they should always be used in the lowest dosage compatible with disease control.

Administration, Inhalation↗

PubMed1995

Dose-related decrease in bone density among asthmatic patients treated with inhaled corticosteroids.

BACKGROUND: Inhaled corticosteroids are being prescribed more commonly and in higher doses than previously in the management of asthma. Although these topically active compounds have less potential for systemic impact than oral steroids, biochemical markers suggest that they are not devoid of systemic side effects. We conducted this study to investigate the effect of commonly prescribed doses of inhaled steroids on bone density. METHODS: We studied 36 patients with asthma. Those in group A (n = 18) had been taking inhaled beclomethasone dipropionate or budesonide in a dosage of 800 micrograms or more per day for at least 1 year. Those in group B (n = 18) had used only bronchodilator therapy. Adrenal function was assessed by morning serum cortisol level and by short adrenocorticotropic hormone stimulation test. Bone turnover was assessed by measurement of serum osteocalcin, alkaline phosphatase, and urinary pyridinium cross-links. Bone mineral density was measured by dual-energy x-ray absorptiometry with a Hologic QDR-1000 densitometer (Hologic Inc., Waltham, Mass.). RESULTS: Group A, mean age (SD) = 36.6 (8.4) years, had used inhaled corticosteroids at a mean dose of 1323 micrograms/day (range, 800 to 2000 micrograms/day) for a median duration of 24 months. Group B, mean age (SD) = 33.4 (8.1) years, had not been taking any form of steroid. Four patients from group A had suppressed morning serum cortisol; three of these had abnormal adrenocorticotropic hormone stimulation test results. All patients in group B had normal baseline adrenal function and an appropriate response to adrenocorticotropic hormone. Mean serum osteocalcin level in group A was significantly lower than that in group B (8.8 vs 14.2 ng/ml, p = 0.0003). Bone density measurements showed parallel changes: in group A the mean Z score (SD) of the femoral neck was -0.78 (1.02), significantly below predicted normal values (p = 0.0025). Mean Z scores of the lumbar spine and of femoral Ward's triangle were not significantly reduced. In group B the mean Z scores of the lumbar spine, femoral neck, and femoral Ward's triangle were all within normal limits. In group A the dose duration of inhaled corticosteroid therapy corrected for body mass index correlated negatively with bone density and adrenal function measurements. CONCLUSION: We conclude that the regular use of conventional doses of inhaled corticosteroids by patients with asthma can suppress adrenal function and decrease bone density in a dose-related fashion.

Administration, Inhalation↗

PubMed1995

Health-care utilization after near-fatal asthma.

Near-fatal asthma has been repeatedly associated with an increased risk of premature death. Despite a higher risk, death after near-fatal asthma remains infrequent. Few studies have examined the long-term outcome of those who experience a near-fatal event but do not succumb to asthma. We therefore contacted patients who had an episode of near-fatal asthma 5 to 10 years earlier and documented their use of health-care services for asthma. Each index case was compared with two age-matched controls who had been hospitalized for severe but not near-fatal asthma within 2 years of the index case admission. Thirty-seven index cases and 74 control subjects were assessed. Demographics did not distinguish the two groups. Availability of primary care physicians and asthma specialists were similar. There was no difference in the frequency of hospitalizations, emergency room visits, or visits to physicians for asthma between the two groups. ICU admissions were extremely infrequent. Although the mean number of ICU admissions per subject were similar in the year preceding our contact (0.03 +/- 0.16 in each group), there was a trend toward ICU admissions occurring more often in the near-fatal group (0.62 +/- 1.67 vs 0.31 +/- 0.91 admissions/subject). Days away from work were more frequent in the control group (3.5 +/- 5.5 vs 1.6 +/- 3.3 d/yr) including days away from work in the year preceding our contact (8.9 +/- 43 vs 1.8 +/- 6.1 d). The data suggests that with regards to characteristics and health-care utilization, it may not be possible to distinguish people with near-fatal asthma from those who are hospitalized without a near-fatal event.

Acute Disease↗

PubMed1994

Medical personnel's knowledge of and ability to use inhaling devices. Metered-dose inhalers, spacing chambers, and breath-actuated dry powder inhalers.

BACKGROUND: Current treatment strategies for asthma and chronic obstructive pulmonary disease (COPD) emphasize the inhalation route, yet patients often misuse metered-dose inhalers (MDI). To address this problem, patient education by medical personnel has been recommended and a variety of alternate inhaler devices have been developed. METHODS: We surveyed medical personnel to assess their knowledge of and ability to use three widely used inhaler devices; MDI, MDI with a spacing chamber (Aerochamber, Trudell Medical, Canada), and a breath-actuated multidose dry powder inhaler (Turbuhaler, Astra Pharmacy, Inc., Conada). Thirty respiratory therapists (RT), 30 registered nurses (RN), and 30 medical house staff physicians (MD) were asked to demonstrate the use of each device using placebo inhalers and to answer 11 clinically relevant questions related to the use and maintenance of the tested devices. RESULTS: The RT's percent mean knowledge score (67 +/- 5 percent) was significantly higher than those achieved by either the RNs (39 +/- 7 percent) or the MDs (48 +/- 7 percent) (for all p < 0.0001). Similarly, percent mean demonstration scores for each device were significantly higher for RTs than either RN or MD groups; for MDI, 97 +/- 3 percent versus 82 +/- 13 percent and 69 +/- 24 percent, respectively (p < 0.0001); for the Aerochamber, 98 +/- 2 percent versus 78 +/- 20 percent and 57 +/- 31 percent (p < 0.0001); and for the Turbuhaler, 60 +/- 30 percent versus 12 +/- 23 percent and 21 +/- 30 percent (p < 0.0001). Knowledge of and practical skills with the devices were roughly proportional to the length of time the device had been in clinical use, Turbuhaler demonstration scores being lower than either MDI or Aerochamber scores (p = 0.05 and p = 0.09, respectively). More RTs (77 percent) had received formal instruction on the use of devices at school than either RNs (30 percent) or MDS (43 percent) (p < 0.05). CONCLUSION: We conclude that (1) many medical personnel responsible for monitoring and instructing patients in optimal inhaler use lack rudimentary skills with these devices, (2) nurses and physicians seldom receive formal training in the use of inhaling devices, and (3) newer inhaling devices designed to obviate problems of technique are at present less likely to be used well by medical personnel soon after their introduction.

Clinical Competence↗