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PubMed2001

[The feasibility of a limited operation for primary lung cancer].

We reviewed 33 patients who underwent a limited operation for primary lung cancer between 1980 and 1998. These cases were divided into three groups; a poor risk group consisting of 18 patients who had a high risk such as pulmonary or cardiac dysfunction and who underwent partial resection of a lung, a reduction group consisting of 9 patients who had advanced lung cancer or uncontrolled cancer of an organ other than the lung and who underwent partial resection, and an active limited operation group consisting of 6 patients who underwent segmentectomy with lymphoadenectomy for the treatment of early lung cancer. The 1 and 3-year survival rates in the poor risk group, reduction group and active limited operation group were 73.9, 60.0, 100%, and 63.4, 0.0, 100%, respectively. The results of limited operations performed for poor risk cases were satisfactory in terms of both functional state and prognosis. Limited operations performed to reduce tumor in advanced lung cancer cases did not improve the prognosis. Although an active limited operation for a case of early lung cancer remains controversial with respect to indication, it is thought that this operation is not inferior to a standard radical operation (lobotomy with mediastinal lymphoadenectomy) in selective cases in which the maximum tumor diameter is 2 cm or less. The indication for a limited operation must be further examined from aspects of tumor size, tumor histology and the other factors of the tumor.

Adenocarcinoma↗
PubMed2002

[Impact of a 10-year nation-wide campaign on knowledge of sensible drinking limits in Denmark].

INTRODUCTION: In Great Britain and in Denmark, strong efforts have been made to influence knowledge on the upper threshold of hazardous drinking. In Denmark, a campaign has been repeated every week 40 from 1990 to 2001 with information on the sensible drinking limits of 21 drinks per week for men and 14 drinks per week for women. The aim of this study was to examine the effect of this ongoing campaign on the level of knowledge of sensible drinking limits for men and women. MATERIAL AND METHODS: Every year from 1994 to 1999, random representative samples of 1,030 adult Danes were interviewed on the telephone. RESULTS: Our main finding was that the level of knowledge of sensible drinking limits for own sex increased in all subsets of the population throughout the period. However, at the end of the study period (1999), a total of 80% of highly educated young (18-25 years of age) men knew sensible drinking limits for own sex, while only 35% of uneducated older (more than 65 years old) men had knowledge on sensible drinking limits. The proportions were similar among women: Subjects admitting an intake higher than sensible for own sex, i.e. 21 and 14 drinks per week, respectively, had the highest knowledge of these drinking limits. DISCUSSION: We conclude that public health campaigns, such as the sensible drinking limit campaign, certainly has an impact on the level of awareness in the general population. Furthermore, those drinking more than 21 and 14 drinks per week, respectively, are reached by these campaigns.

Adult↗
PubMed2003

International policies on alcohol impaired driving: are legal blood alcohol concentration (BAC) limits in motorized countries compatible with the scientific evidence?

Borkenstein et al. (1974) study indicated that drivers with BACs of 0.05 to 0.09 per cent were twice as likely to crash as drivers with a zero BAC. Drivers with BACs from 0.10 to 0.14 per cent were ten times as likely to have a fatal crash in 1964. There have been numerous efforts during the history of motorized countries to control the consumption of alcohol and the problems associated with it through legislative mandate, it was not until the 1970s that acceptance of legal BAC (Blood Alcohol Concentration) limits laws became widespread. In particular, as more and more people drive automobiles, the number of traffic accidents involving drunken drivers has soared, and many of these are known to be related to the consumption of alcohol. Thus, legislators find themselves under increasing pressure to find a reasonable and fair solution to the question of alcohol impaired driving, as the scientific evidence about alcohol consumption level and psycho motor functions impairment came to clear. A landmark event in the development of policies regarding impaired driving was the establishment of the fact that consumption of alcohol does, in fact, increase the probability of traffic crashes. Legal limit laws specify a maximum permissible BAC limit for drivers. Currently, a BAC laws range from zero tolerance and 0.02 to 0.10% constitutes prima facie evidence in most countries for 'Driving under Influence of Alcohol.' This latter standard is too permissive, as driving skills deteriorate and crash involvement risk increases beginning at 0.02%. There are consequences attached to setting a BAC limit so high that a 72 kg man can drink five bottles of beer and still be under legal limit. In this sense high legal BAC limit may influence people to make bad estimates of their relative risk of injury or death while driving. Provided there is adequate political will, millions of lives could be saved in the coming years. This review is an attempt to examine in detail the available information about legal BAC limit laws, and issue of considerable interest to both policy makers and the public.

Accidents, Traffic↗
PubMed2004

Prediction of academic and behavioural limitations in school-age survivors of bacterial meningitis.

AIM: To develop a prediction rule to identify postmeningitic children at high risk of academic and behavioural limitations. METHODS: 182 children (mean age 10 y; range 5-14) were selected from a cohort of 674 school-age survivors of bacterial meningitis. These children had neither meningitis with "complex onset", nor prior cognitive or behavioural problems, nor severe disease sequelae. On average, 7 y after the meningitis, they were evaluated using an "Academic Achievement Test", and their parents filled in the "Child Behaviour Checklist". By reviewing the medical records, potential risk factors for academic and/or behavioural limitations were collected. Independent predictors were identified using multivariate logistic regression analysis, leading to the formulation of a prediction rule. RESULTS: The cumulative incidence of academic and/or behavioural limitations among children who survived bacterial meningitis without severe disease sequelae was 32%. The prediction rule was based on nine independent risk factors: gender, birthweight, educational level of the father, S. pneumoniae, cerebrospinal fluid leukocyte count, delay between admission and start of antibiotics, dexamethasone use, seizures treated with anticonvulsive therapy, and prolonged fever. When 10 was taken as a cut-off point for the risk score computed using this rule, 76% of the children with limitations could be identified, while 38% of the children in the cohort were selected as at risk for these limitations. CONCLUSION: With a prediction rule based on nine risk factors, postmeningitic children at high risk of developing academic and/or behavioural limitations could be identified. Additional research is required to further validate this prediction rule. In the future, a careful follow-up of high risk children may enhance early detection and treatment of these limitations.

Adolescent↗
PubMed2004

[Stomatal and nonstomatal limitations of photosynthesis in mung bean leaves under the combination of enhanced UV-B radiation and NaCl stress].

Stomatal and nonstomatal limitations of photosynthesis in mung bean (Phaseolus radiatus L.) leaves under the combination of 0.35 W/m(2) UV-B radiation and 0.4% NaCl stress were studied. Separated or combined treatments of enhanced UV-B radiation and NaCl stress all resulted in a decrease in net photosynthetic rate, stomatal conductance, photosynthetic ability, efficiency of CO(2) carboxylation and Rubisco content, and the extent of those decreases enhanced obviously with the increase of treatment days. Intercellular CO(2)concentration tended to decrease in short period, followed by a gradual increase and to be higher than the control on the seventh day after treatment under NaCl stress alone, while a tendency of gradual increase was observed under enhanced UV-B radiation alone or two stresses combined and the concentration was higher than the control after three day of treatments. By contrast, the tendency of stomatal limitation value was just reverse to the intercellular CO(2) concentration, but the stomatal limitation value was always higher than control under all stress conditions (did not include that on the fifth day under the combined stresses). As compared with an individual stress the effect of combined stress on the above parameters was more serious. These results indicate that under all stress conditions the inhibition of photosynthesis in mung bean leaves is the results of both stomatal and nonstomatal limitations. And the stomatal limitation is dominant in short period, nonstomatal limitation becomes the dominant one in longer period. The decrease in Rubisco content leads to nonstomatal limitation of photosynthesis under all stresses.

Phaseolus↗
PubMedDate not supplied

Prevalence of activity limitation among persons living with HIV/AIDS in British Columbia.

BACKGROUND: As antiretrovirals increase the life expectancy of persons living with HIV, quality of life issues become more important. Little research has examined the types and levels of activity limitations among HIV-positive populations. The objective of this report is to compare the levels of limitations among HIV-positive persons to the general population. METHODS: The BC Persons With AIDS (BCPWA) Society consists of approximately 3,500 HIV-positive members. A recent survey conducted among BCPWA members included a section assessing activity limitations. Prevalence of limitations in this group was compared to the general population of BC using the National Population Health Survey (NPHS) to calculate standardized prevalence ratios (SPR). RESULTS: Compared to the general BC population, BCPWA members were more likely to be male, aged over 30 years, not to have graduated from high school, unemployed, living alone and having a household income less than $10,000 per year. The SPR for activity limitations among male participants applying the rates of limitation among the general population of BC was 9.4 (8.4-10.6). The SPR for women was 9.9 (7.2-11.1). Using an NPHS rate restricted to individuals who reported a chronic condition, the SPR for males was 6.0 (5.9-6.5) and for females was 7.0 (5.8-8.2). INTERPRETATION: Limitations on activity are prevalent, even when comparing those with high CD4 counts and restricting the standard to those with chronic conditions. These findings suggest that implementation of programs offering support with everyday tasks would be of value in this population.

Acquired Immunodeficiency Syndrome↗
PubMed2004

[Severe limitation of mouth opening].

Limitation of mouth opening is a common source of referral to an orofacial pain clinic with a proposed diagnosis of Temporomandibular Joint Dysfunction (TMD). The word "trismus" is defined by the American academy of orofacial pain as: "Myospasm of masticatory muscles specifically causing limited jaw opening; early symptom of tetanus". Therefore, once trismus is suspected, TMD should be ruled out. However, it is not uncommon to find the usage of this term to describe severe limitation of opening by causes other than myospasm, therefore posing the risk of misdiagnosis. The purpose of this article is to describe the differential diagnosis of hard end limitation of opening with emphasis on the clinical tools used to differentiate between muscle source of hard end limitation and other sources of hard end limitation. Several cases of hard end limitation of mouth opening are presented and through them major principles of orofacial diagnosis are discussed.

Diagnosis, Differential↗
PubMed1992

Sliding limits to safe levels of drinking.

A random sample of 106 male surgical outpatients at the York District Hospital were asked for their views on safe limits, before receiving alcohol education. Subjects were asked to state how much alcohol they considered safe to drink and in addition, to attribute degrees of risk of alcohol related harm to levels of alcohol intake. Twenty-seven (34.1%) of the respondents did not acknowledge a further risk from a level of alcohol intake that was above their declared safe limit. These inconsistent subjects were identified as having sliding limits rather than safe limits. Subjects were also asked to state how much alcohol they had consumed over the preceding week. Twenty-three (29.1%) of the subjects reported their alcohol consumption as greater than their safe limit. Furthermore, the drinkers who were found to be exceeding their limits were more likely to have sliding limits than those who were not (P less than 0.05).

Adult↗
PubMed2005

Reliability and validity of the Buruli ulcer functional limitation score questionnaire.

The reliability and validity of the earlier developed Buruli ulcer functional limitation score (BUFLS) questionnaire was assessed. Of 638 former Buruli ulcer patients (of 678 individuals examined), sufficient items on daily activities (>or= 13 of the 19) were applicable to calculate a score. To determine the validity, the functional limitation scores of the 638 individuals were compared with the global impression of the limitations, range of motion (ROM), and the social impact (change of occupation or education) of Buruli ulcer. To determine inter-observer reliability, the functional limitation score was reassessed in 107 participants within one and three weeks after the first interview by another interviewer and interpreter. Both global impression and ROM correlated well with the functional limitation scores (rho = 0.66 and rho = 0.61). The inter-observer reliability of 107 participants as measured by an intra-class correlation coefficient of 0.86 was very good. The functional limitation scores measured in the second assessment were significantly higher than in the first assessment. This should be taken into account when the functional limitation score is used for the individual patient. The BUFLS can be used as for between group comparisons of endpoints in clinical trials and in the planning of resources.

Humans↗
PubMed2005

[Review and evaluation of limited resection for early lung cancer].

Limited resection for early lung cancer has been associated with significantly higher local recurrence rates based on previous reports such as those from lung cancer study groups. On the other hand, a few groups demonstrated that patients with small peripheral cancer who undergo limited resection have comparable survival rates with those who undergo lobectomy. Recent advances in radiologic investigation and pathologic analysis have broadened the indications for limited resection. Since the introduction of the adenocarcinoma classification by Noguchi surgery for localized bronchioloalveolar carcinoma has focused on limited resection. Caution is necessary when performing wedge resection even if 10 mm or less in diameter and in compromised segmentectomy for early lung cancer. Although limited resection is still controversial intentional segmentectomy for localized bronchioloalveolar carcinoma or less than 20 mm or less in diameter may be recommended without evidence-based medicine. It is important to accumulate further evidence clarifying the survival and function benefits of limited resection. New therapeutic modalities for limited surgery for small-sized lung cancer may increase patient life expectancy.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed2006

Effect of P.G. 600 on rebreeding performance in sows limit-fed during lactation.

The objective was to determine whether treatment with 400 IU PMSG and 200 IU hCG (P.G. 600; Intervet America, Inc., Millsboro, DE, USA) at weaning improved rebreeding performance in sows that were limit-fed during lactation. Crossbred sows were allowed ad libitum access to feed or were limited to 3.2 kg of feed/day during an 18-day lactation. At weaning, limit-fed sows received im treatment with P.G. 600 (n = 16) or saline (n = 19) and ad libitum-fed sows received saline (n = 18). The percentage of sows in estrus by day 7 post-weaning was greater (p<0.05), and the weaning-to-estrus interval was shorter (p<0.05), for ad libitum-fed sows compared to limit-fed, saline-treated sows, with limit-fed, P.G. 600-treated sows having intermediate values that were not different from the other two groups. The percentage of sows pregnant and the numbers of corpora lutea and embryos at day 30 post-mating were not different (p>0.1) among groups. In summary, low feed intake during lactation decreased the percentage of sows that displayed estrus within 7 days after weaning and increased the weaning-to-estrus interval. These effects were at least partially remediated by gonadotropin treatment. Pregnancy rate, and litter size at day 30 of gestation, were similar for ad libitum- and limit-fed sows and not affected by P.G. 600 treatment in limit-fed sows.

Adipose Tissue↗
PubMedDate not supplied

[Early stress tests following an uncomplicated myocardial infarct: a comparison between symptom-limited and submaximal tests].

To compare the diagnostic and prognostic usefulness of symptom-limited versus load-limited submaximal stress testing, 76 patients, during the first week post acute non-complicated myocardial infarction, were submitted to a symptom-limited Naughton-modified protocol stress test. At 2 METs, 3 METs and maximal effort levels, the tests were classified as positive or negative following the currently used criteria. After a mean follow-up of 15 months, the symptom-limited protocol showed the best sensitivity (95%), specificity (78%), positive (64%) and negative (98%) predictive value, and also the highest risk ratio (27.4) for prediction of subsequent coronary events (2p less than 0.01 vs 2 METs, 3 METs and 2D-Echocardiogram results). Forward stepped multiple correlation analysis indicated independent prognostic value for the results of the symptom-limited stress test (R2: .52 p less than 0.01) and for the location of the myocardial infarction (R2: .05 p less than 0.05) only. In addition, the discriminant prognostic power of the symptom-limited protocol was significant after the fourth month of follow-up (2p less than 0.05 vs submaximal tests and 2D-Echo). Therefore, we recommend the performance of a symptom-limited stress test during the first week post acute non-complicated myocardial infarction, provided that all coronary active medication has been withheld 24 hours before the test.

Adult↗
PubMed1988

Benzodiazepines, but not beta carbolines, limit high frequency repetitive firing of action potentials of spinal cord neurons in cell culture.

Effects of benzodiazepines (BDZs) and beta carbolines (beta CCs) on sustained repetitive firing at high frequency (SRF) of action potentials of mouse spinal cord neurons in cell culture were examined using intracellular recording techniques. In control medium neurons responded to depolarizing current pulses with SRF. Limitation of SRF was produced by the anticonvulsant BDZs (diazepam, clonazepam, nitrazepam and lorazepam) at low to mid nanomolar concentrations, by a convulsant BDZ which does not bind to high affinity BDZ receptors (Ro 5-4864) at high nanomolar concentrations and by a BDZ receptor weak partial agonist (Ro 15-1788) at micromolar concentrations. The limitation of SRF was accompanied by use- and voltage-dependent reduction of maximal rate of rise (Vmax) of sodium-dependent action potentials. Partial agonist and inverse agonist beta CCs did not limit SRF at concentrations up to 200 nM. The limitation of SRF by diazepam was not prevented by inverse or partial agonists at the BDZ receptor, including Ro 15-1788 and the beta CCs. These findings suggest that limitation of SRF was produced by binding of BDZs, but not beta CCs, to voltage-dependent sodium channels and not to high affinity central BDZ receptors, and that BDZs limit SRF by slowing recovery of sodium channels from inactivation. We propose that the limitation of SRF may contribute to the efficacy of BDZs against generalized tonic-clonic seizures and status epilepticus.

Action Potentials↗
PubMed1986

Sodium valproate, but not ethosuximide, produces use- and voltage-dependent limitation of high frequency repetitive firing of action potentials of mouse central neurons in cell culture.

Effects of the anticonvulsant drugs sodium valproate (NaVP) and ethosuximide (ES) on mouse central (spinal cord and cortical) neurons in primary dissociated cell culture were studied using intracellular recording techniques. Drug effects on two properties of the neurons were assayed: the ability to sustain high frequency repetitive firing (SRF) of sodium-dependent action potentials, a voltage sensitive nonsynaptic membrane property; and the amplitude of responses to iontophoretically applied gamma-aminobutyric acid (GABA), a postsynaptic effect of this inhibitory amino acid neurotransmitter. At concentrations equivalent to the clinically useful therapeutic range in cerebrospinal fluid (6-200 microM), NaVP limited SRF to a few action potentials in both spinal cord and cortical neurons during long (450 msec) depolarizing current pulses. The limitation of SRF was paralleled by use-dependent reduction of maximal rate of rise (Vmax) of the action potentials and prolongation of recovery of Vmax from inactivation. This action was similar to limitation of SRF produced by phenytoin and carbamazepine. The 2-en-metabolite of NaVP, sodium 2-propyl, 2-pentenoate, did not limit SRF at 12 to 120 microM. However, the diphenyl analog of NaVP, sodium diphenylacetate, limited SRF at concentrations between 4.7 to 23.5 microM. ES did not affect SRF at concentrations up to 700 microM. At concentrations of 120 to 1000 microM, including the upper limit of therapeutic range, NaVP did not affect postsynaptic GABA responses in 80% of spinal cord neurons. In the remaining 20%, GABA responses were augmented less than 33%. ES reduced slightly (22%) GABA responses at a high concentration (700 microM). These findings suggest that limitation of SRF may be an important cellular mechanism by which NaVP, but not ES, exerts anticonvulsant efficacy and that neither ES nor NaVP have anticonvulsant action by enhancing postsynaptic GABA action.

Action Potentials↗
PubMed1995

Results of a limited resection for compromised or poor-risk patients with clinical stage I non-small cell carcinoma of the lung.

BACKGROUND: Patients with stage I non-small cell carcinoma of the lung may be unable to undergo a standard curative resection, such as lobectomy, due to various medical reasons. Whether or not a limited resection is superior to radiotherapy in these patients, both in terms of long-term prognosis and treatment morbidity, is unknown. STUDY DESIGN: We retrospectively reviewed our results in treating compromised or poor-risk patients with clinical stage I non-small cell carcinoma of the lung who had received either a limited resection or radiotherapy. Seventeen patients underwent a limited resection (nine wedge resections and eight segmentectomies), while 18 patients received radiation therapy. RESULTS: The five-year survival rates for patients in the limited resection group and the radiation treatment group were 55.0 and 14.4 percent, respectively. A log-rank analysis showed a significant difference between the two groups (p = 0.004). Furthermore, the survival rate of the patients having a limited operation was significantly better than that of patients achieving either complete response or partial response from radiotherapy (18.8 percent at five years, p = 0.008). Recurrence at the surgical margin occurred in four patients in whom the tumor was greater than 2 cm in longest diameter. The incidence of severe treatment-related complications was not different between the limited operation group and the radiotherapy group (11.8 compared to 11.1 percent). CONCLUSIONS: The results indicate that a limited resection for patients with poor-risk clinical stage I carcinoma of the lung has an advantage over radiotherapy, especially for tumors measuring less than 2 cm in longest diameter.

Adenocarcinoma↗
PubMedDate not supplied

Lower legal blood alcohol limits for young drivers.

To reduce the involvement of young drivers in alcohol-related crashes, 29 States and the District of Columbia have established lower legal blood alcohol limits for drivers younger than age 21 than for adult drivers. Of these, 12 lowered the legal limit for young people prior to 1991. To assess the impact, these 12 States were paired for comparison with 12 nearby States matched for legal drinking age and timing of changes in that law. Among drivers ages 15-20, fatal crashes involving a single vehicle at night are three times more likely than other fatal crashes to be alcohol-related. Whether the proportion of fatal crashes that involved single vehicles at night declined more among young drivers targeted by lower blood alcohol limits than among young drivers of the same age in comparison States was examined. The maximum available equal number of pre- and post-law years were compared in each pair of States. During the post-law period, the proportion of fatal crashes that involved single vehicles at night declined 16 percent among young drivers targeted by lower blood alcohol laws, whereas it rose 1 percent among drivers of the same age in comparison States where blood alcohol limits were not changed (P < .001). Among adults, the proportion of fatal nocturnal crashes that involved single vehicles declined 5 percent in the group of States with the lowered levels for young people during the period after the law was enacted and 6 percent in the group of neighboring comparison States. The proportion of fatal crashes that involved single vehicles at night declined 22 percent among drivers in States with .00 percent limits, whereas it declined only 2 percent among drivers of the same age in comparison States (P <.003). Among those targeted by .02 percent BAL limits, the proportion of fatal crashes that involved single vehicles at night declined 17 percent. It rose 4 percent in comparison States(P = .005). No significant difference appeared between States that lowered blood alcohol levels to the range of .04-.06 percent relative to comparison States.If all States adopted .00 or .02 percent limits for drivers ages 15-20, at least 375 fatal single vehicle crashes at night would be prevented each year.

Accidents, Traffic↗
PubMed1996

Development of allometric equations to establish normal limits for M-mode echocardiographic measurements in the Italian population. Gruppo Ligure Della Società Italiana di Ecografia Cardiovascolare.

BACKGROUND: Despite general acceptance of the normal limits for M-mode echocardiographic measurements established in the U.S.A. in the late seventies, several studies have shown that those limits of normality have some limitations which restrict their use in clinical practice, and that these limits should be specific for the population that should be studied. To date, however, there is no reference method to calculate normal limits of M-mode echocardiographic measurements in the Italian population. METHODS: 627 healthy volunteers (382 males, 245 females) ranging in age from 4 to 89 years, were prospectively examined, using two-dimensionally directed M-mode echocardiography, in 13 echocardiographic laboratories. End-diastolic and-systolic left ventricular diameters, interventricular septum and posterior wall thickness, end-diastolic aortic dimension and end-systolic left atrial diameter were measured following the recommendations of the American Society of Echocardiography. Age, gender, weight, height, heart rate and blood pressure were used as determinants of the echocardiographic measurements. The specificity of the resulting normal limits of echocardiographic measurements was then tested on an independent population of 145 normal subjects (92 males, 53 females) who were prospectively examined after the development of the model. RESULTS: Gender, age and weight were significant and independent determinants in nearly all the echocardiographic measurements performed. After logarithmic transformation of all the variables, we developed sex specific regression models which allow calculation of 95% prediction intervals for the cardiac chamber size and wall thickness, using an exponential multivariate regression model. Ninety-one percent of the echocardiographic measurements performed on the control population (range 84.6-94.1%) were correctly identified as normal using our model. Conversely, the specificity of the existing reference models developed in the U.S.A. or in the Netherlands identified, respectively, only 77% (range 53.1-92.4%) and 74% (range 53.8-87.6%) of those measurements as normal (p < 0.0001 vs our model for both). Differences in specificity between our models and the U.S. one also persisted after correcting the U.S. model for the Italian population (82.8% versus 91.3%, respectively; p = 0.003). Conversely, differences in specificity between our models and the Dutch ones were no longer detectable after correcting the Dutch models (which has a statistical approach very similar to ours) for the Italian population (91.3 versus 94.7%, respectively; p = NS). CONCLUSIONS: Our study provides reliable mathematical model based on exponential growth (allometric) equations to calculate upper and lower normal limits of M-mole echocardiographic measurements obtained from Italian subjects given their gender, height, weight, heart rate, age and blood pressure.

Adolescent↗
PubMedDate not supplied

Peripheral limiting factors during exercise in chronic lung diseases.

In normal subjects the sensation of general fatigue subjectively limits the physical performance, whereas in patients with reduced respiratory function the sensation of breathlessness is the common limiting symptom. Patients with chronic obstructive lung disease may adopt an intermittent exercise pattern (e.g. when climibing stairs), in which the work periods are brief in duration but relatively high in intensity. The immediate ventilatory demand can in that way be reduced. The local metabolism of the working muscles can meet the increased demand, which demonstrates that peripheral factors are unlikely to limit the physical performance in these patients. For evaluating the importance of peripheral factors limiting the exercise tolerance of daily activities, such as stair-climbing or walking uphill, such activities should specifically be studied considerating also the exercise pattern shown by the patient. Even in bronchitic patients with reduced arterial oxygen tension there are no evidence that the skeletal muscles are working under more anaerobic conditions than in normal persons at the same relative work load. The blood lactate as related to the heart rate usually lies within normal limits. In patients with respiratory failure, however, lack of energy supply from the energy rich compounds may develop. Thus, only in extreme situations can the exercise performance of the respiratory patients be expected to be specifically limited by peripheral factors. Physical inactivity leads to changes in the muscle metabolism as in normal persons with reduced aerobic capacity in the muscles. The specific effects of steroid treatment on the muscle function in patients with chronic obstructive disease have not been studied, but may be an important factor limiting muscular performance at certain types of exercises.

Heart↗