Impact on readmission rates and mortality of a chronic obstructive pulmonary disease inpatient management guideline.

AIMS: Chronic obstructive pulmonary disease (COPD) is a common condition associated with considerable morbidity, mortality and hospital admissions. However, published COPD management guidelines have major limitations and lack practical summaries. We aimed to optimally develop, implement, and evaluate a multidisciplinary COPD inpatient management 'ACCORD' guideline, including prompts for comprehensive day one assessments through to a discharge criteria checklist. METHOD: Two intervention and two control public teaching hospitals in Adelaide, South Australia, took part, with pre-intervention (721 COPD admissions over 7 months) and intervention phases (509 COPD admissions over 7 months). During the intervention stage the ACCORD guideline was placed in the case notes on the day of admission or soon after. Readmissions were categorized as either emergency or elective and compared between the study arms, as were mortality and potential confounders (age, gender, number of comorbidities), with Poisson regression analysis. RESULTS: Of case notes of eligible COPD patients, 60% had the ACCORD guideline placed, of which 76% had evidence of use as judged by completion of guideline entry and tick boxes. The ACCORD guideline was associated with an increase in elective admissions and a reduction in emergency admissions in the intervention group in relation to the control group (P < 0.01), with no difference in overall admissions or death rates. CONCLUSIONS: The ACCORD guideline was associated with a shift from emergency admissions to more planned elective care, suggesting more proactive care of health problems, but without overall reduction in admissions.

Disordered respiration as a levodopa-induced dyskinesia in Parkinson's disease.

Symptomatic respiratory disturbance as a consequence of levodopa (L-dopa) therapy for Parkinson's disease (PD) has been described only rarely and may be underrecognized in clinical practice. We report on two patients with PD in whom the introduction or augmentation of L-dopa therapy was associated with the development of irregular and rapid breathing. Analysis of breathing patterns before and after L-dopa demonstrated a striking change in respiratory rate after administration of L-dopa, with the emergence of irregular tachypnea alternating with brief periods of apnea, in a pattern consistent with a central origin. In both cases, the temporal relationship of the respiratory disturbance to the administration of L-dopa suggested a peak-dose drug effect. Previous reports of L-dopa-induced respiratory dyskinesia are reviewed, and the potential mechanisms whereby L-dopa might influence the central control of respiration to produce irregular breathing patterns are discussed.

Obstructive sleep apnoea: a review of the orofacial implications.

Obstructive sleep apnoea is a complex multifactorial condition produced by a combination of anatomical and physiological factors. There is a significant associated mortality and morbidity to obstructive sleep apnoea. There is an at least 25 per cent increased mortality from cardiovascular disease when obstructive sleep apnoea patients are compared to age and gender matched healthy people. Obstructive sleep apnoea sufferers also have a much higher industrial and motor vehicle accident rate. Management of the condition should be undertaken by a multidisciplinary team including respiratory physicians, sleep laboratory technicians, otorhinolaryngologists, oral and maxillofacial surgeons and dental specialists. The diagnostic and therapeutic interactions of team members are the key to successful treatment. The treatment regime utilises nasal continuous positive airway pressure devices, mandibular advancement splints and soft and hard tissue surgery. This review provides the dental practitioner with an introduction to obstructive sleep apnoea with particular emphasis on the orofacial aspects.

Tuberculosis notifications in Australia, 1999.

Australia has one of the lowest incidence of tuberculosis in the world. The crude annual notification rate for tuberculosis (TB) has remained stable at between 5 and 6 per 100,000 population since 1991. In 1999, there were a total of 1,159 TB notifications in Australia of which 1,117 were new TB cases, and 42 were relapsed cases. The corresponding annual notification rate for new and relapsed TB was 5.9 and 0.2 per 100,000 population respectively. People born overseas accounted for 83 per cent of the notified cases. TB notification rates remain highest among overseas-born residents from high prevalence countries, and indigenous Australians. The lowest rates of disease are in the non-indigenous, Australian born population and data from the last 7 years indicate that the rate of tuberculosis in this population is continuing to fall.

Sleep apnoea related hypoxia is associated with cognitive disturbances in patients with tetraplegia.

Sleep disordered breathing is common in patients with tetraplegia. Nocturnal arterial hypoxemia and sleep fragmentation due to sleep apnoea may be associated with cognitive dysfunction. We therefore studied the influence of sleep disordered breathing on neuropsychological function in 37 representative tetraplegic patients (mean age 34 +/- 9.7 years). Thirty percent (11 of 37 patients) had clinically significant sleep disordered breathing, defined as apnoea plus hypopnoea index (AHI) greater than 15 per hour of sleep. Most apnoeas were obstructive in type. Seven patients (19%) desaturated to < 80% during the night. Neuropsychological variables were significantly correlated with measures of sleep hypoxia, but not with the AHI and the frequency of sleep arousals. The neuropsychological functions most affected by nocturnal desaturation were: verbal attention and concentration, immediate and short-term memory, cognitive flexibility, internal scanning and working memory. There appeared to be a weak association between the presence of severe sleep hypoxia and visual perception, attention and concentration but no association was found between sleep variables and depression scores. We concluded that sleep disordered breathing is common in patients with tetraplegia and may be accompanied with significant oxygen desaturation. The latter impairs daytime cognitive function in these patients, particularly attention, concentration, memory and learning skills. Cognitive disturbances resulting from sleep apnoea might adversely affect rehabilitation in patients with tetraplegia.

The Australian National Asthma Campaign: effects of public education activities based on mass media.

INTRODUCTION: The National Asthma Campaign (NAC) was formed in 1990 as a coalition of the key professional organizations concerned with asthma and its management in Australia. It has conducted multifaceted educational activities targeting health care professionals, people with asthma, and the general public. Between November 1991 and March 1993, an educational mass media campaign was developed to inform people about new approaches to preventive asthma therapy and how people with symptoms of asthma should talk to their doctor or pharmacist about new management and monitoring strategies. Evaluation was based on McGuire's communication/persuasion model for assessing the impact of mass media campaigns. METHODS: Four serial cross-sectional population surveys of persons over the age of 18 years were conducted in four major Australian cities using structured telephone interviews. Information was sought on asthma campaign awareness and knowledge or use of appropriate asthma management practices. RESULTS: There was an increasing trend in awareness of asthma messages in the media and of appropriate message recall across the two-year period. Knowledge about the need to use preventive therapy for asthma improved significantly. Among those with asthma there was a significant upward trend in the proportion who discussed asthma with their doctor or pharmacist and who used peak flow meters and written asthma management plans. CONCLUSIONS: The net impact of the NAC and other activities has been an increase in awareness about asthma in Australia. These campaigns relied on the relatively nonselective medium of television to raise awareness and to start to change attitudes to asthma. The challenge is to build on these trends to further reduce morbidity and mortality due to asthma.

Sleep apnoea in patients with quadriplegia.

BACKGROUND: This study was undertaken to establish the prevalence of, and the factors contributing towards, sleep disordered breathing in patients with quadriplegia. METHODS: Forty representative quadriplegic patients (time since injury > 6 months, injury level C8 and above, Frankel category A, B, or C; mean (SE) age 35.0 (1.7) years) had home sleep studies in which EEG, EOG, submental EMG, body movement, nasal airflow, respiratory effort, and pulse oximetry (SpO2) were measured. Patients reporting post traumatic amnesia of > 24 hours, drug or alcohol abuse or other major medical illness were excluded from the study. A questionnaire on medications and sleep was administered and supine blood pressure, awake SpO2, spirometric values, height, and neck circumference were measured. RESULTS: A pattern of sustained hypoventilation was not observed in any of the patients. Sleep apnoeas and hypopnoeas were, however, common. Eleven patients (27.5%) had a respiratory disturbance index (RDI, apnoeas plus hypopnoeas per hour of sleep) of > or = 15, with nadir SpO2 ranging from 49% to 95%. Twelve of the 40 (30%) had an apnoea index (AI) of > or = 5 and, of these, nine (75%) had predominantly obstructive apnoeas-that is, > 80% of apnoeas were obstructive or mixed. This represents a prevalence of sleep disordered breathing more than twice that observed in normal populations. For the study population RDI correlated with systolic and diastolic blood pressure and neck circumference. RDI was higher in patients who slept supine compared with those in other postures. Daytime sleepiness was a common complaint in the study population and sleep architecture was considerably disturbed with decreased REM sleep and increased stage 1 non-REM sleep. CONCLUSIONS: Sleep disordered breathing is common in quadriplegic patients and sleep disturbance is significant. The predominant type of apnoea is obstructive. As with non-quadriplegic patients with sleep apnoea, sleep disordered breathing in quadriplegics is associated with increased neck circumference and the supine sleep posture.

Felodipine improves pulmonary hemodynamics in chronic obstructive pulmonary disease.

Pulmonary hypertension in chronic obstructive pulmonary disease (COPD) is associated with a poor prognosis. Reduction of pulmonary artery pressure in COPD by prolonged oxygen treatment has been shown to be associated with increased survival. In an attempt to find a suitable pharmacologic method of reducing pulmonary artery pressure and pulmonary vascular resistance in COPD, we enrolled 13 stable pulmonary-hypertensive, hypoxemic COPD patients in a study to test the effects of felodipine, a relatively new, vascular-selective calcium antagonist. Doppler echocardiography was used to estimate pulmonary artery pressure and cardiac output before treatment, 2, 7, and 12 weeks during felodipine treatment (10 to 20 mg/d), and after a 1-week placebo washout period. Measurements of lung function, arterial blood gases, and exercise capacity during an incremental bicycle ergometer test were also performed at intervals during the study period. Three patients withdrew from the study and of the remaining 10, 8 had some side effects of medication (peripheral edema or headache) that improved either spontaneously or following a reduction in drug dose. In the 10 patients who completed the study (8 male; mean age, 67 years), felodipine resulted in significant reductions in mean pulmonary artery pressure (22 percent) and total pulmonary (vascular) resistance (30 percent) and increases in cardiac output (15 percent) and stroke volume (13 percent) compared with baseline measurements and those taken after placebo washout. These effects were sustained over the 12 weeks of felodipine treatment. There was no adverse effect of felodipine treatment on pulmonary gas exchange at rest or during exercise and no change in lung function or exercise capacity. We conclude that in pulmonary hypertensive, hypoxemic COPD patients, felodipine substantially improves pulmonary hemodynamics.

Hypoxia episodes during sleep in high tetraplegia.

To determine whether oxygen desaturation occurs during sleep in high tetraplegics, 10 neurologically stable male patients (aged 17 to 55 years) with complete motor lesions (C4 to C6) had continuous pulse oximetry recordings and sleep observations on two nights. The patients were studied during admissions for nonrespiratory problems (eg, pressure sores, urinary infection, respite). Lung function tests and daytime arterial blood gases were also measured. Mean forced vital capacity was 46% of predicted, but mean awake PaO2 and PaCO2 were normal (95.0 mmHg and 42.8 mmHg, respectively). Three subjects showed severe nocturnal oxygen desaturation spending greater than 10% of the time overnight with arterial oxyhaemoglobin saturation (SaO2) levels of less than 90%. For the group as a whole, the percentage of time spent under 90% SaO2 correlated with body mass index. Mean overnight SaO2 correlated inversely with body mass index and directly with maximal expiratory pressure, a measure of respiratory muscle strength. Low overnight SaO2 was also associated with higher levels of injury. The pattern of nocturnal oxygen desaturation observed was episodic and was suggestive of obstructive sleep apnoea during rapid eye movement (REM) sleep. Levels of nocturnal oxygen desaturation similar to those observed in the three most severely affected patients have been shown, in other disorders, to be associated with cognitive impairment, cardiovascular disease and increased mortality. Our results suggest up to a third of high tetraplegics may be at risk of potentially serious nocturnal hypoxic episodes.

Nebuhaler versus wet aerosol for domiciliary bronchodilator therapy. A multi-centre clinical comparison.

OBJECTIVE: To compare the clinical effectiveness and patient acceptance of a large spacer device (Nebuhaler) for delivery of metered dose aerosol (MDI) terbutaline with nebulised wet aerosol terbutaline. DESIGN: Randomised open crossover study over two sequential four week treatment periods, following a two week run-in. SETTING: Multi-centre including five adult thoracic units and three paediatric centres throughout Australia. PATIENTS: Thirty-eight adults and 23 children with clinical asthma and reversible airflow obstruction (increase in forced expiratory volume in one second [FEV1] of greater than or equal to 15% in response to inhaled bronchodilator) entered the study proper. Six adults and one child withdrew. INTERVENTIONS: Terbutaline was administered four times daily via Nebuhaler/MDI or nebuliser. Clinical assessment with spirometry and peak flow readings was made after run-in and at the end of each treatment period. Patients recorded on diary cards daily peak expiratory flow rates and symptom scores and comparisons of these results for each treatment period were made. At the completion of the study patients answered a treatment preference questionnaire. RESULTS: No differences were found between the two treatment periods in diary card peak flow recordings and symptom score data, and in clinical assessment of spirometry and peak expiratory flow rates. There were also no differences between spirometry and peak flow values recorded at the clinic at randomisation and at the end of each treatment period, suggesting stable basal airflow obstruction over the period of the study. Thirty-two per cent of adults and 52% of children preferred the Nebuhaler/MDI combination, mainly because of convenience of use. Treatment preference was not related to any measured index of lung function. CONCLUSIONS: MDI terbutaline delivered via Nebuhaler provides clinical benefit similar to that of wet aerosol terbutaline in the long-term domiciliary management of patients with stable airflow obstruction.

Sleep fragmentation and ventilatory responsiveness to hypercapnia.

It has been postulated that sleep disruption may change ventilatory chemoresponsiveness to hypercapnia and hypoxia and thereby contribute to the development of respiratory failure in some patients with obstructive sleep apnea syndrome (OSAS) or with other respiratory disorders. Some studies have demonstrated a reduction in ventilatory chemoresponsiveness in normal subjects after one night of total sleep deprivation. However, sleep fragmentation rather than total sleep deprivation is usual in patients. In this study, therefore, we measured hypercapnic ventilatory responsiveness (HCVR) and spirometry in 13 healthy male subjects (18 to 30 yr of age) after two consecutive nights of severe sleep fragmentation (arousal to an auditory stimulus after each minute of sleep) and compared the results with those obtained in the same subjects after normal sleep. Sleep fragmentation and normal sleep were separated by a week, and the order of intervention was randomized from patient to patient. No significant differences were observed in the slope or position of the HCVR curve after sleep fragmentation or in forced expiratory volumes. Although it is possible that a more prolonged period of sleep fragmentation than that used in this study may have an effect on HCVR, the results suggest that sleep fragmentation is an unlikely cause of progressive respiratory failure in patients with OSAS or with other respiratory disorders.

Obligatory nasal breathing: effects on snoring and sleep apnoea.

OBJECTIVE: To test the effects on snoring and sleep disordered breathing of a dental prosthesis (Snore-No-More) which is designed to decrease snoring by preventing mouth breathing during sleep. DESIGN: A crossover controlled trial. Each subject was studied on two nights a week apart. There was a control (no treatment) night and an experimental (treatment) night. The order of control and experimental nights was randomised. SETTING: The Royal Adelaide Hospital Sleep Laboratory. PARTICIPANTS: Fourteen male volunteers (age range, 36-59 years) were studied. All had a history of chronic snoring but denied other symptoms of obstructive sleep apnoea syndrome. INTERVENTIONS: On experimental nights subjects wore the dental prosthesis for the whole study period. On control nights no device was worn. MAIN OUTCOME MEASURES: Studies were conducted overnight during the subject's normal sleep period. The following measurements were made: (i) frequency and loudness of snores; (ii) frequency of disordered breathing events (apnoeas and hypopnoeas); (iii) mean and minimum arterial oxygen saturation while asleep; and (iv) sleep stages. RESULTS: The dental prosthesis did not change the mean frequency or mean intensity of snores. The number of sleep disordered breathing events per hour of sleep decreased by approximately one-third on experimental nights (mean +/- SEM events/h: control, 24.7 +/- 5.3; experimental, 16.1 +/- 3.3, P less than 0.05). Neither sleep architecture nor arterial oxygen saturation differed between control and experimental nights. CONCLUSION: Snores using the dental prosthesis Snore-No-More to produce obligatory nasal breathing are unlikely to experience clinical benefit.

Tuberculosis surveillance in the South Australian aboriginal community.

Tuberculosis (TB) is still a significant problem in Aboriginal people. There are higher rates of active TB and evidence of continuing transmission among this group. We sought to define the specific epidemiological risks and best methods of surveillance for TB in Aboriginal people in South Australia. We compared the incidence of active TB in Aboriginal people in South Australia with that of the total number of cases in non-Aboriginal people from 1978 to 1988, and studied the prevalence of infection in four Aboriginal communities in South Australia. Incidence rates of active TB were four times higher in South Australian Aboriginal people than the total South Australian rates. Specific age analysis revealed higher active disease notification rates in Aboriginal people aged 45-54 years and 55-64 years. The notification rate for Aboriginal men was almost three times the rate for women. Standardized incidence ratios of active TB cases for Aboriginal communities were higher in rural and traditional communities than in urban Aboriginal people. Infection prevalence, measured by tuberculin skin testing, varied from 7.7% to 30.8% in the different communities but did not correlate with the standardized incidence ratios. We conclude that (i) South Australian Aboriginal people are suffering a higher rate of active TB disease than the total South Australian community, and (ii) that the disease and infection rates vary between communities and between age and sex groups. The discrepancy between disease notifications rates, as measured by standardized incidence ratios, and infection prevalence requires further investigation. To improve TB control in Aboriginal people, programmes need to be altered to be more appropriate for this group.

Mycobacterium bovis as an occupational hazard in abattoir workers.

Five cases of bovine tuberculosis occurred in a two year period in South Australia, which represents a higher incidence than in previous years. All five patients had a history of employment in an abattoir (although four different abattoirs were involved) and four of the cases had pulmonary or pleural TB. A voluntary survey of one of the abattoirs was conducted which discovered the fifth case of active pulmonary TB. We suggest that bovine TB should be considered an occupational hazard in abattoir workers, and that suitable pre-employment screening programmes for workers be established. The transmission of disease in these cases is almost certainly by inhalation causing pulmonary TB and is therefore different from the 'classic' form of bovine TB transmitted by ingestion of infected milk and resulting in extrapulmonary disease.

The effects of aminophylline on sleep and sleep-disordered breathing in patients with obstructive sleep apnea syndrome.

The methylxanthine derivatives are known to have respiratory stimulant properties. To determine whether these drugs would improve obstructive sleep apnea, 10 male patients with obstructive sleep apnea (OSA) (Apnea Index greater than 15/h) were given infusions of aminophylline and a saline placebo on 2 separate nights a week apart, using a randomized crossover design. There was a significant decrease during aminophylline infusion in the frequency of those apneas, which contained periods of complete respiratory inactivity (central and mixed apneas; placebo, 4.3 +/- 1.8/h; aminophylline, 0.7 +/- 0.5/h; p less than 0.05). There was no change in either the frequency (placebo, 31.8 +/- 5.9/h; aminophylline, 28.7 +/- 8.7/h; NS) or duration of obstructive apneas. Mean and minimal arterial oxygen saturation values were also unchanged. Sleep architecture was markedly disturbed by aminophylline. There was a reduction in sleep efficiency (placebo, 84.8 +/- 2.0%; aminophylline, 60.2 +/- 5.0%; p less than 0.005), an increase in sleep fragmentation (sleep stage shifts/h: placebo, 11.6 +/- 1.3: aminophylline, 21.0 +/- 2.9; p less than 0.05) and less Stage 2 and more Stage 1 non-REM sleep. We conclude that aminophylline reduces central apnea and the central component of mixed apneas but has no effect on obstructive apnea. Theophylline is therefore unlikely to be therapeutically useful in patients with OSA, and because it leads to marked sleep disruption, its long-term use could conceivably increase the propensity to upper airway occlusion during sleep.