Preoperative portal vein or portal and hepatic vein embolization: DRAGON collaborative group analysis.

BACKGROUND: The extent of liver resection for tumours is limited by the expected functional reserve of the future liver remnant (FRL), so hypertrophy may be induced by portal vein embolization (PVE), taking 6 weeks or longer for growth. This study assessed the hypothesis that simultaneous embolization of portal and hepatic veins (PVE/HVE) accelerates hypertrophy and improves resectability. METHODS: All centres of the international DRAGON trials study collaborative were asked to provide data on patients who had PVE/HVE or PVE on 2016-2019 (more than 5 PVE/HVE procedures was a requirement). Liver volumetry was performed using OsiriX MD software. Multivariable analysis was performed for the endpoints of resectability rate, FLR hypertrophy and major complications using receiver operating characteristic (ROC) statistics, regression, and Kaplan-Meier analysis. RESULTS: In total, 39 patients had undergone PVE/HVE and 160 had PVE alone. The PVE/HVE group had better hypertrophy than the PVE group (59 versus 48 per cent respectively; P = 0.020) and resectability (90 versus 68 per cent; P = 0.007). Major complications (26 versus 34 per cent; P = 0.550) and 90-day mortality (3 versus 16 per cent respectively, P = 0.065) were comparable. Multivariable analysis confirmed that these effects were independent of confounders. CONCLUSION: PVE/HVE achieved better FLR hypertrophy and resectability than PVE in this collaborative experience.

Performance of faecal indicator bacteria, microbial source tracking, and pollution risk mapping in tropical water.

Faecal indicator bacteria (FIB) are used for the assessment of faecal pollution and possible water quality deterioration. There is growing evidence that FIB used in temperate regions are not adequate and reliable to detect faecal pollution in tropical regions. Hence, this study evaluated the adequacy of FIB, including total coliforms (TC), Escherichia coli (EC), Enterococci (IEC), and Clostridium perfringens (CP) in the high-altitude, tropical country of Ethiopia. In addition to FIB, for microbial source tracking (MST), a ruminant-associated molecular marker was applied at different water types and altitudes, and faecal pollution risk mapping was conducted based on consensus FIB. The performances of the indicators were evaluated at 22 sites from different water types. The results indicate that EC cell enumeration and CP spore determination perform well for faecal contamination monitoring. Most of the sub-basins of Lake Tana were found to be moderately to highly polluted, and the levels of pollution were demonstrated to be higher in the rainy season than in the post-rainy season. Markers associated with ruminants (BacR) were identified in more than three quarters of the sites. A bacterial pollution risk map was developed for sub-basins of Lake Tana, including the un-gauged sub-basins. We demonstrate how bacterial pollution risk mapping can aid in improvements to water quality testing and reduce risk to the general population from stream bacteria.

Assessing seasonal nitrogen export to large tropical lakes.

Rivers are exporting increasing amounts of nitrogen (N) to lakes, which is leading to eutrophication. However, the seasonality apparent in nutrient loading, especially in tropical areas, is thus far only partially understood. This study aims to better understand the seasonality and the sources of dissolved inorganic nitrogen (DIN) inputs from sub-basins to tropical lakes. We integrated existing approaches into a seasonal model that accounts for seasonality in human activities, meteorology and hydrology, and we applied the model to the sub-basins of a representative tropical lake: Lake Tana, Ethiopia. The model quantifies the river export of DIN by season, source and sub-basin and also accounts for open defecation to land as a diffuse source of N in rivers. Seasonality parameters were calibrated, and model outputs were validated against measured nitrogen loads in the main river outlets. The calibrated model showed good agreement with the measured nitrogen loads at the outflow of the main rivers. The model distinguishes four seasons: rainy (July-September), post-rainy (October-December), dry (January-March) and pre-rainy (April-June). The river export of DIN to Lake Tana was about 9 kton in 2017 and showed spatial and temporal variability: It was highest in the rainy and lowest in the dry seasons. Diffuse sources from agriculture were important contributors of DIN to rivers in 2017, and animal manure was the dominant source in all seasons. Our seasonal sub-basins and rivers model provides opportunities to identify the main nutrient sources to the lake and to formulate effective water quality management options. An example is nutrient application level that correspond to the crop needs in the sub-basins. Furthermore, our model can be used to analyse future trends and serves as an example for other large tropical lakes experiencing eutrophication.

Tuning protein GlnB-Hs surface interaction with silicon: FTIR-ATR, AFM and XPS study.

Herbaspirillum seropedicae GlnB (GlnB-Hs) is a signal transduction protein involved in the control of nitrogen, carbon and energetic metabolism. The adsorption of GlnB-Hs deposited by spin coating on hydrophilic and hydrophobic silicon forms a thin layer that was characterized using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared attenuated total reflectance spectroscopy (FTIR-ATR). AFM allowed the identification of globular, face-up donut like array of protein on hydrophilic silicon substrate, favoring deprotonated residues to contact the silicon oxide surface. Over hydrophobic silicon, GlnB-Hs adopts a side-on conformation forming a filament network, avoiding the contact of protonated residues with silicon surface. XPS allowed us to determine the protonated and non-protonated states of nitrogen 1s (N 1s). The FTIR-ATR measurements provided information about protein secondary structure and its conservation, after surface adsorption.

Morphology, structure, and magnetism of FeCo thin films electrodeposited on hydrogen-terminated Si(111) surfaces.

In this work we describe the fabrication of FeCo alloy (less than 10 at% Co) thin films from aqueous ammonium sulfate solutions onto n-type Si(111) substrates using potentiostatic electrodeposition at room temperature. The incorporation of Co into the deposits tends to inhibit Fe silicide formation and to protect deposits against oxidation under air exposure. As the incorporation of Co was progressively increased, the sizes of nuclei consisting of FeCo alloy increased, leading to films with a highly oriented body-centered cubic structure with crystalline texture, where (110) planes remain preferentially oriented parallel to the film surface.

Benefit from the inclusion of self-treatment guidelines to a self-management programme for adults with asthma.

This study assessed the long-term efficacy of adding self-treatment guidelines to a self-management programme for adults with asthma. In this prospective randomized controlled trial, 245 patients with stable, moderate to severe asthma were included. They were randomized into a self-treatment group (group S) and a control group (group C). Both groups received self-management education. Additionally, group S received self-treatment guidelines based on peak expiratory flow (PEF) and symptoms. Outcome parameters included: asthma symptoms, quality of life, pulmonary function, and exacerbation rate. The 2-yr study was completed by 174 patients. Both groups showed an improvement in the quality of life of 7%. PEF variability decreased by 32% and 29%, and the number of outpatient visits by 25% and 18% in groups S and C, respectively. No significant differences in these parameters were found between the two groups. After 1 yr, patients in both groups perceived better control of asthma and had more self-confidence regarding their asthma. The latter improvements were significantly greater in group S as compared to group C. There were no other differences in outcome parameters between the groups. Individual self-treatment guidelines for exacerbations on top of a general self-management programme does not seem to be of additional benefit in terms of improvements in the clinical outcome of asthma. However, patients in the self-treatment group had better scores in subjective outcome measures such as perceived control of asthma and self-confidence than patients in the control group.

Behavioural effect of self-treatment guidelines in a self-management program for adults with asthma.

To assess the efficacy of self-management programs it is important to know what behavioural changes take place. This paper assesses whether including self-treatment guidelines (action plans) in a self-management program for adult asthmatics, leads to greater behavioural changes than a program without these guidelines. Patients were randomised into a self-treatment group (n=123) or an active control group (n=122). All subjects received self-management training. Discussed topics included the pathophysiology of asthma, medication and side-effects, triggers, symptoms, smoking, physical exercise, and compliance. The only difference was that the self-treatment group received instructions about self-treatment of exacerbations and the control group did not. At 1 year of follow-up asthma-specific self-efficacy expectancies, outcome expectancies, and asthma-specific knowledge improved significantly in all patients. Only self-treatment group patients demonstrated favourable changes in generalised self-efficacy, social support, and self-treatment and self-management behaviour, in case of a hypothetical scenario of a slow-onset exacerbation. We conclude that our self-management program is effective in changing the behavioural variables, and including self-treatment guidelines (action plans) has added benefit.

Multiple inhalers confuse asthma patients.

This study investigated the influence of the use of different types of inhalers on the adequacy of inhalation technique among adult asthmatics. Three hypotheses were tested: first, patients using only one type of inhaler will demonstrate adequate inhalation technique more often than those with two or more types. Secondly, patients using a combination of dry powder inhalers (DPIs) will demonstrate correct inhalation technique more often than those using the combination of a metered dose inhaler (MDI) and a DPI. Thirdly, some inhalers or combinations of inhalers are more prone to erroneous inhalation technique than others. Adult outpatients with asthma who regularly used inhaled steroid therapy (n=321) participated in the study. The inhalers investigated were MDIs on the one hand, and the DPIs Turbuhaler, Diskhaler, Cyclohaler, Inhaler Ingelheim and Rotahaler on the other. Of 208 adult asthmatics with only one inhaler, 71% made no inhalation errors versus 61% of 113 patients with two or more different inhalers. Of patients with a combination of DPIs 68% performed all essential checklist items correctly, versus 54% of patients with the combination of "regular" MDI and DPI. Patients using only the Diskhaler made fewest errors. Whenever possible, only one type of inhaler should be prescribed. If a combination is unavoidable, combinations of DPIs are preferable to MDI and DPI. The Diskhaler seems to be the most foolproof device.

Inhalation technique of 166 adult asthmatics prior to and following a self-management program.

Self-management of asthma and self-treatment of exacerbations are considered important in the treatment of asthma. For successful self-treatment, medication has to be inhaled correctly, but the percentage of patients inhaling effectively varies widely. As part of a self-management program we checked and corrected inhalation technique. This paper addresses differences among inhalers in relation to patient characteristics and the effect of instruction, 1 year after enrollment. Maneuvers that are essential for adequate inhalation were identified. When errors in inhalation technique were observed, patients were instructed in the correct use of their devices. One year later, inhalation technique was checked again. Only patients who used the same inhaler throughout the entire study period were analyzed. Of the 245 adult asthmatic patients who were enrolled in the self-management program, 166 used the same inhaler throughout the study period. One hundred twenty patients (72%) performed all key items correctly at baseline and this increased to 80% after 1 year. At follow-up, older patients were less likely to demonstrate a perfect inhalation. Patients with a Diskhaler made fewest errors. Adjustment for differences in patient characteristics did not significantly change the results. Because many patients with asthma use their inhaler ineffectively, there is a need to know which inhaler leads to fewest errors. Diskhaler was nominated by this study. When patients are not able to demonstrate adequate inhalation technique in a "tranquil" setting, it is doubtful that they can do so when they experience an exacerbation. Therefore, inhalation instruction should be considered an essential ingredient, not only of self-management programs, but also of asthma patient care in general.

Cerebral metabolic suppression during hypothermic circulatory arrest in humans.

BACKGROUND: Hypothermic circulatory arrest (HCA) is used in surgery for aortic and congenital cardiac diseases. Although studies of the safety of HCA in animals have been carried out, the degree to which metabolism is suppressed in patients during hypothermia has been difficult to determine because of problems with serial measurements of cerebral blood flow in the clinical setting. METHODS: To quantify the degree of metabolic suppression achieved by hypothermia, we studied 37 adults undergoing operations employing HCA. Cerebral blood flow was estimated using an ultrasonic flow probe on the left common carotid artery, and cerebral arteriovenous oxygen content differences were calculated from jugular venous bulb and arterial oxygen saturations. Cerebral metabolic rates while cooling were then ascertained. The temperature coefficient, Q10, which is the ratio of metabolic rates at temperatures 10 degrees C apart, was determined. RESULTS: The human cerebral Q10 was found to be 2.3. The cerebral metabolic rate is still 17% of baseline at 15 degrees C. If one assumes that cerebral blood flow can safely be interrupted for 5 min at 37 degrees C, and that cerebral metabolic suppression accounts for the protective effects of hypothermia, the predicted safe duration of HCA at 15 degrees C is only 29 min. CONCLUSIONS: The safe intervals calculated from measured cerebral oxygen consumption suggest that shorter intervals and lower temperatures than those currently used may be necessary to assure adequate cerebral protection during hypothermic circulatory arrest.

Natural history of descending thoracic and thoracoabdominal aneurysms.

BACKGROUND: A review of 165 patients with chronic dissecting and degenerative aneurysms of the descending thoracic and thoracoabdominal aorta initially managed nonoperatively was carried out to ascertain factors associated with a high risk of rupture. METHODS: Changes in the aneurysms were followed with three-dimensional reconstructions of computed tomograph scans. Risk factors were compared in patients with dissecting and nondissecting aneurysms who experienced rupture, in whom operation was recommended during the course of follow-up, and in those without rupture or operation. RESULTS: Nondimensional variables associated with an enhanced risk of rupture include age, the presence of chronic obstructive pulmonary disease, and even uncharacteristic continued pain. Patients with rupture of dissections had significantly higher blood pressures than survivors, and significantly smaller maximal descending thoracic aortic diameters (median 5.4 cm) than patients with rupture of degenerative aneurysms (median 5.8 cm). The extent of the aneurysm, as reflected by the maximal abdominal aortic diameter, was a significant risk factor for rupture only in nondissecting aneurysms. Mortality from rupture was significantly higher in patients with chronic dissections than in patients with nondissecting aneurysms: 9/10 vs 26/34 (p = 0.004). CONCLUSIONS: Almost 20% of patients followed nonoperatively succumbed to rupture, suggesting that a more aggressive surgical approach toward patients with chronic aneurysms of the descending thoracic and thoracoabdominal aorta is warranted. An individualized risk of rupture within 1 year can now be calculated, and patients whose operative risk is lower than their calculated risk should be offered elective surgery.

Use of somatosensory evoked potentials for thoracic and thoracoabdominal aortic resections.

BACKGROUND: Despite tremendous development in surgical and anesthetic techniques, resection of the thoracic and thoracoabdominal segments of the aorta remain associated with the risk of paralysis. Routine use of somatosensory-evoked potential (SEP) monitoring in patients undergoing surgery of the thoracic aorta has become a standard intra- and postoperative procedure at our institution since its first use in 1993. METHODS: One hundred forty nine (149) thoracic aortic operations were performed during January 1993 through January 1998 using SEP-directed serial sacrifice of paired intercostal arteries. Full, partial, or no cardiovascular bypass was variably used, dictated by anatomy; 49 patients required deep hypothermic circulatory arrest (DHCA). Patients were monitored during both the intraoperative procedure as well for the post-anesthesia period until neurologic stability and/or ability to reproducibly demonstrate lower extremity neurologic competency was established. Postoperative neurologic function was compared to ischemic intervals, extent of aortic resection, number of intercostal arteries sacrificed, type of perfusion, and underlying aortic pathology. RESULTS: Overall mortality in the group was 13 patients (8.7%), with no one cause predominating. Nine patients sustained permanent paraplegia, only 1 of whom lost SEPs during the procedure. Abnormal SEPs were seen in 19 patients, 14 of whom had normal neurologic function after awakening. Three of 19 (15.8%) developed late paraplegia that resolved with medical therapy. Eleven patients (7.4%) developed cerebrovascular accidents (CVA), with the majority (8) appearing in the group undergoing DHCA. The risk of CVA was significantly higher in DHCA patients (p < 0.01) than other patients. No patient with CVA had abnormal SEPs; 4 DHCA patients developed abnormal SEPs, 1 with permanent paralysis. CONCLUSIONS: The routine use of SEP monitoring during thoracic and thoracoabdominal aortic surgery as well as during the postoperative period may be useful in decreasing the observed incidence of paraplegic events associated with these procedures.

Subtypes of acute aortic dissection.

BACKGROUND: This series consists of a 12-year experience with a policy of identifying and replacing the aortic segment containing the primary intimal tear for repair of acute aortic dissection. METHODS: Patients with type A dissection underwent urgent surgery. Patients with type B dissection were referred for surgery based on selective criteria, including aortic dilatation greater than 5 cm. A classification system for acute dissection is described that specifies the site of intimal tear while retaining the clinical relevance of the Stanford system. RESULTS: Of 168 acute dissections, 139 were type A and 29 were type B. The site of intimal tear was as follows: ascending aorta, 83 cases; arch, 32 cases; descending aorta, 29 cases; multiple tears, 11 cases (10 included arch tears); no tear (intramural hematoma), 6 cases; not noted, 7 cases. Only 60% of acute type A dissections arose from solitary intimal tears in the ascending aorta, whereas 30% had arch tears. Hospital mortality for type A dissection was 13.7% (18.8% for arch tears, NS) and 0% for type B. False lumen patency was 57.1% for type A dissection and 18.8% for type B dissection (p = 0.002), yet survival was similar for these groups. Ten-year survival for type A dissection with arch tear (0.51 +/- 0.12) was lower than 10-year survival for type A dissection with ascending tear (0.74 +/- 0.05; p = 0.77), and significantly lower than for type A dissection with descending tear (0.88 +/- 0.12; p = 0.029). CONCLUSIONS: Systematic resection of the primary tear yielded similar hospital mortality, 5-year survival, and aorta-related event-free survival rates for subtypes of acute type A dissection. Excellent results were obtained with a selective approach to type B dissection.

Risk factors for rupture of chronic type B dissections.

OBJECTIVE: This study was an attempt to determine risk factors for rupture and to improve management of patients with type B aortic dissection who survive the acute phase without operation. METHODS: We studied 50 patients by means of serial computer-generated 3-dimensional computed tomographic scans. All patients who did not undergo operative treatment before the completion of at least 2 computed tomographic scans a minimum of 3 months apart after an acute type B dissection were included in the study. The median duration of follow-up was 40 months (range 0.9-112 months). Only 1 patient died of causes unrelated to the aneurysm during follow-up. Nine patients had fatal rupture (18%); 10 patients underwent elective aneurysm resection because of rapid expansion or development of symptoms, and 31 patients remained alive without operation or rupture. Possible risk factors for rupture in patients in the rupture, operative, and event-free groups were compared, as were dimensional data from first follow-up and last computed tomographic scans. RESULTS: Older age, chronic obstructive pulmonary disease, and elevated mean blood pressures were unequivocally associated with rupture (rupture versus event-free survival, P <.05), and pain was marginally significantly associated. Analysis of dimensional factors contributing to rupture was complicated by the fact that patients who underwent elective operation had significantly larger aneurysms and faster expansion rates than did either of the other groups, leaving comparisons of aneurysmal diameter between groups with and without rupture showing only marginal statistical significance. The last median descending aortic diameter before rupture in the rupture group was 5.4 cm (range 3.2-6. 7 cm). CONCLUSIONS: In an environment in which patients with large and rapidly expanding aneurysms are usually referred for surgical treatment, older patients with chronic type B dissections, especially if they have uncontrolled hypertension and a history of chronic obstructive pulmonary disease, are significantly more likely to have rupture than are younger, normotensive patients without lung disease. Neither the presence of a persistently patent false lumen nor a large abdominal aortic diameter appears to increase the risk of rupture. Overall, our nondimensional data strikingly resemble the natural history of patients with nondissecting aneurysms, suggesting that calculations derived from data on chronic descending thoracic and thoracoabdominal aneurysms would provide an overly conservative individual estimate of rupture risk for patients with chronic type B dissection, who tend toward earlier rupture of smaller aneurysms. A more aggressive surgical approach toward treatment of patients with chronic type B dissection seems warranted.

The role of self-treatment guidelines in self-management education for adult asthmatics.

Guidelines on asthma management have changed considerably in the last two decades. Patient education has gained in popularity and especially asthma self-management training is thought to be essential in the treatment of adult asthma. Since 1989 many researchers have added self-treatment guidelines to self-management programmes and several studies have found improvements in health outcomes, such as lung function, quality of life, use of health care facilities and asthma symptoms. However, because of the lack of proper control groups, it is not clear whether this has to be attributed to self-treatment guidelines or to, for example, more education or more medical attention. The only two studies that were placebo controlled did not show an effect of self-treatment. To assess the added benefit of self-treatment guidelines to a self-management programme, randomized 'placebo' controlled trials of sufficient size with sufficient follow-up time are necessary. The only difference between intervention and control groups should be guidelines for self-treatment.

[Knowledge about drugs used by adult patients with asthma for self-treatment]. / Medicijnkennis van volwassenen met astma onvoldoende voor zelfbehandeling.

OBJECTIVE: To assess the knowledge of adult asthmatics about medication for self-treatment. DESIGN: Descriptive. SETTING: Department of Pulmonary Diseases, Medisch Spectrum Twente, Enschede, the Netherlands. METHODS: As a part of a larger project aimed at improvement of self-management and self-treatment, all adults aged 18-65 years in Enschede (population 146,000) reported by the city pharmacists as using medication for asthma or chronic obstructive pulmonary disease, in 1994 were sent a questionnaire including 7 items pertaining to knowledge about lung medication. From among those who failed to respond after a written reminder and an appeal in local papers, a random group of 9% were interviewed by telephone. Of the responders who reported that according to their GPs they had asthma and who had answered the questions on medication, the number of questions answered correctly was counted; in addition, the question was investigated whether their level of knowledge was related to sex, education, use of (inhalation) corticosteroids and the form of explanation received. RESULTS: A total of 4563 questionnaires were sent out: 2259 (50%) usable forms were returned. The responders were better educated than the 192 non-responders interviewed, but did not differ as to age or sex. Of the responders, 1262 (56%) reported that their GPs had told them they had asthma. On average they had answered 2.4 (range: 0-7) out of 7 questions correctly. Previous instruction, number of sources of information, duration of taking medication, use of inhaled steroids, female sex and better education were all positively related with a higher knowledge score in this group. CONCLUSION: Adult asthmatics did not have sufficient knowledge about their medication. Improving such knowledge should therefore be an important element in the development of a self-management programme.

Comparison of a new multidose powder inhaler (Diskus/Accuhaler) and the Turbuhaler regarding preference and ease of use.

Many patients with asthma or chronic obstructive pulmonary disease (COPD) use their inhaler ineffectively. Several studies revealed that inhaler-specific design features contributed significantly to the failure rate, which clearly demonstrates the need for developing more "foolproof" inhalers. This study compared ease of use and patient preference of the Diskus/Accuhaler (DA) with the Turbuhaler (TH). Fifty patients with asthma or COPD aged 15 years and older were included in a randomized, crossover comparison of DA with TH regarding patient preference and ease of use. All had to be naïve to DA and TH, but currently had to be using inhaled medication with another device. Inhalation technique was assessed using inhaler-specific checklists and patients had to state a preference for DA or TH regarding various aspects, as well as overall preference. With DA 46 patients (92%) made no errors regarding essential inhalation maneuvers, compared to 37 patients (74%) using TH (p = 0.023). This difference is exclusively caused by not loading the TH properly. When patients were asked which inhaler they would prefer, 17 wanted the DA, 25 the TH, and 8 did not state a preference. The difference was not significant. TH was favored over DA regarding factors related to size and the number of available dosages. The counting mechanism of the DA was preferred over the TH. It seems that patients have a clear, although not statistically significant, preference for TH, but with the DA fewer patients make crucial errors.

Minimizing spinal cord injury during repair of descending thoracic and thoracoabdominal aneurysms: the Mount Sinai approach.

In an effort to reduce the incidence of spinal cord injury following resection of descending thoracic and thoracoabdominal aneurysms, we have developed a multifaceted approach to maximize spinal cord perfusion which involves monitoring spinal cord function using somatosensory evoked potentials (SSEPs) intraoperatively and postoperatively. Intercostal and lumbar intersegmental vessels are sacrificed in a gradual stepwise fashion before the aneurysm is incised: none of these vessels is reattached unless SSEPs are abnormal following temporary occlusion, and this has not yet been observed. Postoperative spinal cord perfusion is maximized by keeping arterial pressure high and by draining cerebrospinal fluid if intrathecal pressure is elevated. Only two cases of permanent paraplegia have developed in 95 patients. Multivariate analysis showed extensive aneurysms (spanning 10 or more intersegmental arteries) and a history of smoking as the only significant risk factors for development of spinal cord injury.

Compliance with inhaled medication and self-treatment guidelines following a self-management programme in adult asthmatics.

Two of the principal components of self-management are compliance with medication and adherence to self-treatment guidelines. The aim of this study was to evaluate compliance objectively. Twenty two adult asthmatics attended a self-management programme. During a 2 week run-in period, compliance with inhaled steroids and peak expiratory flow (PEF) were electronically-registered. For PEF this resulted in a personal best value (PBV). Subsequently, patients attended four educational group sessions. During the four weeks of follow-up, patients were instructed to measure their PEF on a fixed day of the week and when they experienced an increase in symptoms. If PEF fell below 80% of PBV, patients had to double their use of inhaled steroids; if PEF fell below 60%, they had to start a short course of oral steroids. During run-in, mean compliance was 83% and compliance per patient varied from 6 to 106%. During follow-up, on days without exacerbation, compliance with inhaled steroids increased by 12% (95% confidence interval (95% CI) 3-21%) compared to run-in, ranging 21-200%. On days when patients should have doubled their inhaled steroids, compliance decreased by 28% (95% CI -39 to -17), and compliance ranged 46-94%. Of the 10 patients who should have doubled their medication, only three did so, whilst four increased the use of inhaled steroids but only by one or two puffs; three patients did not alter their behaviour. In five patients (24%) PEF fell below 60% of their PBV, after which four started prednisolone (self-report). In conclusion, even after a formal self-management programme, patients with asthma comply only partially to self-treatment guidelines. Most are willing to increase, but not double, their inhaled steroids. This suggests that more emphasis is needed to reassure patients about the safety of inhaled steroids.

Are high generalised and asthma-specific self-efficacy predictive of adequate self-management behaviour among adult asthma patients?

In asthma self-management training, often self-treatment guidelines are included, because increased knowledge of asthma alone is not sufficient to change behaviour. One way to achieve behavioural changes is by increasing the patient's general and asthma-specific self-efficacy expectancies. This refers to beliefs in one's capabilities to execute the recommended course of action successfully. We wanted to assess whether high generalised and asthma-specific self-efficacy expectancies were predictive of adequate self-management and self-treatment behaviour. A questionnaire was sent to 4563 persons (18-65 years) who had used inhaled medication in 1993. Self-management and self-treatment behaviour were operationalised through a hypothetical scenario of a slow-onset asthma exacerbation. Of all 1262 asthmatic patients, 39.3% showed adequate self-treatment behaviour (self-adjusting their inhaled or oral steroids when appropriate). Age, asthma-specific outcome expectancies and knowledge were predictive of adequate self-treatment. Adequate self-management behaviour (self-treatment or seeking medical help) was observed in 56.4% of patients. Intentions towards self-management and asthma-specific knowledge were significant. Only knowledge has a relevant influence on both. Asthma-specific knowledge is the only factor that seems relevant for adequate self-management and self-treatment behaviour, which might be explained by the hypothetical nature of the scenario. When patients experience a real asthma exacerbation, self-efficacy expectancies will become more important. Only if knowledge of what to do is present will patients be able to show proper self-management and self-treatment behaviour. Our results suggest that self-treatment guidelines are only effective in combination with patient education, which is important for optimal control of their disease.