Is it really useful to repeat outpatient pulmonary rehabilitation programs in patients with chronic airway obstruction? A 2-year controlled study.

STUDY OBJECTIVES: To answer the following questions: in patients with chronic airway obstruction (CAO), (1) can pulmonary rehabilitation lead to similar short-term gains at successive, yearly interventions, and (2) is there any real clinical or physiologic long-term benefit by yearly repetition of pulmonary rehabilitation programs (PRPs)? DESIGN: Randomized, controlled clinical study. SETTING: Pulmonary rehabilitation center. PATIENTS: Sixty-one CAO patients studied 1 year after completing an initial 8-week outpatient PRP (PRP1). INTERVENTION: Patients were randomly classified into two groups. A second PRP (PRP2) was completed by the first group (group 1) but not by the second group (group 2). One year later, a third PRP (PRP3) was performed by both groups. MEASUREMENTS: Lung function, cycloergometry, walking test, dyspnea, and health-related quality of life (HRQL) were assessed before and after PRP2, and before and after PRP3. The numbers of hospitalizations and exacerbations over the year were also recorded. RESULTS: Complete data sets were obtained from 36 patients (17 patients in group 1 and 19 patients in group 2). The two groups did not differ in any parameter either before PRP1, after PRP1, or at randomization. There was no significant change over time for airway obstruction in either group. After PRP2, exercise tolerance, dyspnea, and HRQL improved in group 1. Nevertheless, 1 year later, patients of group 1 did not differ from patients of group 2 in any outcome parameter, such that in comparison to before PRP1, only HRQL was still better in both groups 24 months after PRP1. Yearly hospitalizations and exacerbations per patient significantly decreased in both groups in the 2 years following PRP1, when compared to the 2 years prior. Nevertheless, at the 24-month follow-up visit, a further reduction in yearly exacerbations was observed only in group 1 but not in group 2 in comparison to what was observed at the 12-month follow-up visit. The PRP3 resulted in improvement in exercise tolerance in both groups. CONCLUSION: In patients with CAO, an outpatient PRP can achieve benefits in HRQL and a decreased number of hospitalizations, which persist for a period of 2 years. Successive, yearly interventions lead to similar short-term gains but do not result in additive long-term physiologic benefits. Further reduction in yearly exacerbations seems to be the main benefit of an additional PRP.

Time course of pulmonary function before admission into ICU. A two-year retrospective study of COLD patients with hypercapnia.

Changes in cardiopulmonary function were retrospectively evaluated back to two years before acute exacerbations requiring ICU admission in 16 COLD patients with chronic hypercapnic respiratory insufficiency (age: 61 +/- 6 years, group A). Fifteen hypercapnic COLD patients matched for age, sex, lung function, and blood gas values not requiring an ICU admission in a period of two years, served as control subjects (age: 66 +/- 7, group B). Periodic assessments of spirometry, arterial blood gas values, echocardiography, body weight, and red blood cell count performed in stable state were compared for differences between groups and changes over a period of two years. The results indicated that basal body weight, rate of deterioration over time in FEV1, VC, blood gas values, bicarbonates, and RVD may be related to the necessity of ICU admission in COLD patients with hypercapnic respiratory insufficiency.

In-hospital short-term training program for patients with chronic airway obstruction.

OBJECTIVE: To compare the functional benefits and relative costs of administering an intense short-term inpatient vs a longer outpatient pulmonary rehabilitation program (PRP) for patients with chronic airway obstruction (CAO). DESIGN: Retrospective case-control study. SETTING: Pulmonary ward and outpatient clinic of a rehabilitation center. PATIENTS: Forty-three patients (case subjects) selected on the basis of selection criteria were compared with control subjects matched to them for age, sex, FEV(1), and diagnosis of either COPD or asthma. Case subjects performed 10 to 12 daily sessions (5 sessions a week) of inpatient PRP; control subjects performed 20 to 24 sessions (3 sessions a week) of outpatient PRP. MEASUREMENTS: At baseline and after the PRP, an incremental exercise test was performed, including evaluation of dyspnea and leg fatigue by Borg scale (D and F, respectively) at each workload step. The cost of PRP was also evaluated. RESULTS: Both PRPs resulted in similar significant improvements in cycloergometry peak workload (from 68 +/- 18 to 82 +/- 22 and from 75 +/- 17 to 87 +/- 27 W in case subjects and control subjects, respectively), isoload D (from 6.4 +/- 1.6 to 4.2 +/- 1.8 for case subjects and from 8.5 +/- 1.9 to 6.3 +/- 2.4 for control subjects) and isoload F (from 6.6 +/- 1.8 to 4.2 +/- 1.8 for case subjects and from 8.9 +/- 1.9 to 7.0 +/- 1.8 for control subjects). Although the single daily session was less expensive, the outpatient PRP total costs were greater because of the higher number of sessions and the cost of daily transportation. CONCLUSIONS: In patients with CAO, a shorter inpatient PRP may result in improvement in exercise tolerance similar to a longer outpatient PRP but with lower costs. Whether a shorter outpatient PRP may get physiologic and clinical benefits, while further reducing costs, must be evaluated by future controlled, randomized, prospective studies.

Exhaled nitric oxide and exercise in stable COPD patients.

STUDY OBJECTIVE: To evaluate exhaled nitric oxide (eNO) during exercise in patients with stable COPD. SETTING: Outpatient evaluation in a rehabilitation center. PATIENTS: Eleven consecutive male patients with stable COPD (age, 65 +/- 6 years; FEV(1), 56 +/- 10% predicted). Eight healthy (six men; age, 51 +/- 16 years) nonsmoking, nonatopic volunteers served as control subjects. METHODS: In each subject, a symptom-limited cycle ergometry test was performed by monitoring eNO with the tidal-breath method to assess eNO concentration (FENO) and output (VNO) at rest, peak exercise, and recovery time. RESULTS: Resting FENO (9.8 +/- 5.1 and 14.1 +/- 6.3 parts per billion, respectively) and VNO (4.2 +/- 2.0 and 5.9 +/- 3.4 nmol/min, respectively) were lower, although not significantly, in COPD patients than in control subjects. In both groups, FENO significantly decreased whereas VNO significantly increased during exercise. Both variables returned to baseline during the recovery time. Peak exercise VNO, but not FENO, was significantly lower in COPD patients than in control subjects (7.9 +/- 5.4 and 12.7 +/- 6.0 nmol/min, respectively, p < 0.05). The rise in VNO was weakly correlated to oxygen consumption VO(2)) both in control subjects (r = 0.31, p = 0. 002) and in COPD patients (r = 0.22, p = 0.03). FENO showed an inverse correlation to VO(2) in both groups (r = -0.53, p = 0.000; r = -0.31, p = 0.003 in control subjects and COPD patients, respectively). CONCLUSIONS: In patients with mild and moderate COPD, eNO during exercise parallels that observed in normal control subjects. VNO, but not FENO, is significantly reduced at peak exercise in COPD patients as compared with control subjects. The long-term effects of exercise training on eNO has to be evaluated by further studies.

Non-invasive modalities of positive pressure ventilation improve the outcome of acute exacerbations in COLD patients.

OBJECTIVE: 1) To compare the clinical usefulness of both non-invasive pressure support ventilation (NPSV) and non-invasive intermittent positive pressure ventilation in assist-control (A/C) mode (NIPPV) in chronic obstructive lung disease (COLD) patients with acute hypercapnic respiratory failure: 2) to compare retrospectively the usefulness of non-invasive mechanical ventilation (NMV) with standard medical therapy alone. DESIGN: Prospective randomized retrospective study. SETTING: 2 Respiratory intermediate intensive units. PATIENTS: 29 COLD patients (age: 62 +/- 8 years) with chronic respiratory failure were hospitalized in a department for rehabilitation during acute relapses of their disease. They were transferred to our intermediate intensive care unit (IICU) and submitted randomly to either NPSV (16 patients) or NIPPV (13 patients). MEASUREMENTS AND RESULTS: Blood gas analysis, dynamic flows, clinical variables, success rate, time of ventilation, side effects and subjective score of compliance to therapy. Therapy was considered successful when endotracheal intubation was avoided and patients were returned to their condition prior to exacerbation. No statistically significant difference was found between NPSV and NIPPV in success rate (NPSV 87.5%; NIPPV 77%) or in time of ventilation (NPSV: 69 +/- 49; NIPPV: 57 +/- 49 h). A better compliance to non-invasive mechanical ventilation (NMV) was found in NPSV patients than in NIPPV patients; side effects were observed less frequently in the NPSV group. Comparison of the success rate of NMV was retrospectively performed with 35 control COLD patients with chronic respiratory insufficiency who had undergone an acute relapse of their disease in the 2 years preceding the institution of the IICU and had been treated with oxygen and medical therapy alone. Patients submitted to NMV showed a greater success rate than control (82 versus 54%) after a period of ventilation ranging from 4-216 h. CONCLUSION: Non-invasive mechanical ventilation performed either by NPSV or NIPPV may improve the outcome of acute exacerbations of COLD, as compared to medical therapy alone. NPSV seems to be more acceptable to patients in comparison with NIPPV.

Non-invasive mechanical ventilation in severe chronic obstructive lung disease and acute respiratory failure: short- and long-term prognosis.

OBJECTIVE: To evaluate the short- and long-term prognosis of patients with chronic obstructive lung disease (COLD) who had noninvasive mechanical ventilation (NMV) for acute respiratory failure (ARF). DESIGN: Retrospective study. SETTING: Two respiratory intermediate intensive care units. PATIENTS: Two groups of patients suffering from COLD and an ARF episode requiring mechanical ventilation. Group 1 (30 patients) was given NMV using face masks (aged 64 +/- 9 years; pH = 7.28 +/- 0.05; PaCO2 = 83 +/- 18 mmHg; PaO2/FIO2 = 141 +/- 61). Group 2 (27 patients) was composed of control patients (aged = 65 +/- 8 years; pH = 7.26 +/- 0.05; PaCO2 = 75 +/- 17 mmHg; PaO2/FIO2 = 167 +/- 41) given MV using endotracheal intubation (EI) when clinical and functional conditions had further deteriorated because the medical therapy failed and NMV was not available at the time. Causes of ARF were in group 1 and 2 respectively: pneumonia in 8 (27%) and 11 (41%), acute exacerbation of COLD in 19 (63%) and 14 (52%) and pulmonary embolism in 3 (10%) and 2 (7%) patients. MEASUREMENTS AND RESULTS: Success rate, mortality during stay in ICU (at 3 months and at 1 year), and the need for rehospitalization during the year following ARF were measured in this study. Group 1 showed a success rate of 74%, only 8/30 patients needing EI and conventional MV. In group 2, the weaning success was 74% (20/27 patients). The mortality for group 1 was 20% in IICU, 23% at 3 months and 30% at 1 year; and 26% for group 2 in ICU, 48% at 3 months and 63% at 1 year. Within each group 1-year mortality was greater (p < 0.01) in patients with pneumonia. The number of new ICU admissions during the follow-up at 1 year was 0.12 versus 0.30 in groups 1 and 2 respectively (p < 0.05). CONCLUSION: For patients suffering from COLD who have undergone ARF, avoiding EI by early treatment with NMV is associated with better survival in comparison to patients bound to invasive MV. Pneumonia as a cause of ARF may worsen the prognosis in both groups of patients.

Exhaled nitric oxide and exercise tolerance in severe COPD patients.

To answer the question as to whether pulmonary rehabilitation programs (PRP) induced increase in exercise tolerance (ET) is associated with increased levels of exhaled nitric oxide (eNO) in COPD patients of different degrees of severity, we designed a prospective and controlled study. Forty-seven stable COPD patients underwent an 8-week outpatient multidisciplinary PRP including supervised incremental exercise. Fractional eNO concentration (FE(NO)) and peak work-rate (W(peak) were assessed baseline (T-1), atthe end of 1-month run-in period (T0), and after (T1) the PRP. Lung function, walking test, health-related quality of life (HRQL) were also recorded. Patients were divided into three groups according to disease severity: 17 severe [FEV1 35 (5)% pred] COPD patients, seven of them with cor pulmonale; 15 mild [FEV1 78 (6)% pred], and 15 moderate [FEV1 56 (6)% pred] COPD patients. FE(NO) did not differ at T-1 and T0 (mean absolute change (SD): 0.03 (0.09) 95% CI-0.01, 0.16, 0.06 (1.03) 95% CI 0.03, 0.75 and 0.05 (0.06) 95% CI 0.02, 0.11 ppb in mild, moderate and severe patients, respectively). As compared to T0, both W(peak) (by 17,15 and 10%, respectively) and FE(NO) (by 29, 24 and 16%, respectively) significantly increased in all groups, but not in patients with cor pulmonale. A significant correlation between pre- and post-PRP changes in Wpeak and FE(NO) was found both in mild to moderate (r = 0.79, P < 0.00001) and severe (r = 0.76, P < 0.001) COPD patients. After a PRP, improvement in ET is associated with an increase in eNO also in most severe COPD patients, but not in those with cor pulmonale.

Physiological and symptom determinants of exercise performance in patients with chronic airway obstruction.

To evaluate the physiological and symptom determinants of exercise performance (EP) as measured by a 6-min walking test (6MWD), Watt(max), and peak oxygen consumption (VO2 ml/min/kg), 105 patients with chronic airway obstruction (CAO) [50 chronic obstructive pulmonary disease (COPD): 44 men, aged 63+/-7 years, forced expiratory volume in 1 sec (FEV1) forced vital capacity (FVC)(-1)% 54+/-13; and 55 asthmatic: 23 men, aged 55+/-10 years, FEV1 FVC(-1) % 65+/-10] underwent evaluation of 6MWD, symptom limited cyclo-ergometer exercise test, spirometry, respiratory muscle function, arterial blood gases and sensation of dyspnoea [using the Borg scale, Visual Analogue Scale (VAS) and Baseline Dyspnoea Index (BDI)]. A hierarchical method of analysis identified the residual volume (RV), total lung capacity (TLC)(-1) ratio, BDI and the patient's age as the strongest and most consistent correlates of EP (r2 = 0.14-0.21). The correlation between EP and its various determinants was not influenced by diagnosis. The relationship between breathlessness and EP was different between men and women: at any given level of exercise, women were more breathless than men. In multivariate analyses that contained both RV TLC(-1) and BDI, the RV TLC(-1) ratio was the strongest correlate of EP, although the BDI remained a significant covariate. Overall, age was the major determinant of EP but inclusion of the RV TLC(-1) ratio and the BDI into the model explained a further 9-15% of the variance in EP. These three covariates together explained 26-34% of the variance between patients. We conclude that in stable CAO patients, the prediction of exercise capacity by anthropometric, demographic, clinical and physiological variables is likely to be low. Age, pulmonary hyperinflation and dyspnoea are the strongest and most consistent correlates of impaired exercise performance. Airways obstruction, measured during expiration using FEV1, does not appear to be a predictor of physiological impairment. These results underline the importance of performing exercise evaluation in CAO patients.

Lack of additional effect of adjunct of assisted ventilation to pulmonary rehabilitation in mild COPD patients.

Different modalities of assisted ventilation improve breathlessness and exercise tolerance in patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to evaluate the effects of the addition of assisted ventilation during exercise training on the outcome of a structured pulmonary rehabilitation programme (PRP) in COPD patients. Thirty-three male patients with stable COPD (mean (SD) forced expiratory volume in 1 s (FEV1) 44 (16) % pred), without chronic ventilatory failure, undergoing a 6-week multidisciplinary outpatient PRP including exercise training, were randomised to training during either mask proportional assist ventilation (PAV: 18 patients) or spontaneous breathing (SB: 15 patients). Assessment included exercise tolerance, dyspnoea, leg fatigue, and health-related quality of life (HRQL). Five out of 18 patients (28%) in the PAV group dropped out due to lack of compliance with the equipment. Both groups showed significant post-PRP improvements in exercise tolerance (peak work rate difference: 20 (95% Cl 2.4-37.6) and 14 (3.8% CI to 24.2) W in PAV and SB group, respectively), dyspnoea and leg fatigue, but not in HRQL, without any significant difference between groups. It is concluded that with the modality and in the patients assessed in this study assisted ventilation during training sessions included in a multidisciplinary PRP was not well tolerated by all patients and gave no additional physiological benefit in comparison with exercise training alone.

Relevance of dyspnoea and respiratory function measurements in monitoring of asthma: a factor analysis.

Previous studies in patients with stable chronic obstructive pulmonary disease have demonstrated that objective measures (lung volumes and respiratory muscle force) and clinical or subjective measures (symptoms of breathlessness and exercise tolerance) are quantities that independently characterize the conditions of these patients. Such an evaluation has not been previously applied in patients with stable bronchial asthma. Sixty-nine patients with stable chronic asthma underwent evaluation of static (functional residual capacity, FRC) and dynamic [forced expiratory volume in 1 sec (FEV1) and forced vital capacity, FVC] lung volumes; respiratory muscle strength (RMS), by measuring maximal inspiratory and expiratory pressures, and exercise capacity by means of the 6-min walking distance (6MWD). Chronic exertional dyspnoea was assessed by the Baseline Dyspnoea Index (BDI) focal score and by the Medical Research Council (MRC) scale. Statistical evaluation was performed by applying factor analysis. Three factors accounted for 78% of the total variance in the data: FEV1, FVC loaded on a factor I; RMS, FRC and 6MWD loaded on a factor II; dyspnoea ratings loaded on a factor III. Post-hoc analysis by randomly dividing the patients into two subgroups gave the same results. In asthmatic patients, airway obstruction appeared as an independent dimension or factor. Dyspnoea independently characterized the condition of asthma. Submaximal exercise tolerance could not be associated with the symptom of breathlessness. Evidence of independent factors support the validity of routine, multi-factorial assessment and the primary goal of treatment to alleviate symptoms and improve functional capacity in stable asthmatics.

Different modes of noninvasive intermittent positive pressure ventilation (IPPV) in acute exacerbations of COLD patients.

Patients with chronic obstructive lung disease may suffer from acute exacerbations of their disease, which may lead to acute respiratory failure necessitating endotracheal intubation and mechanical ventilation. We have compared retrospectively the results obtained with nasal positive pressure ventilation and those of standard medical therapy in acute relapses of severe COLD. The study showed that nasal IPPV (NIPPV) in control mode delivered for approximately 1 h, four times daily, six days a week over a 21 day period, does not result in independent improvement of acute exacerbation of COLD. In the next study the data seem to indicate, in apparent contrast, a marked reduction in the need for endotracheal intubation using noninvasive ventilation, both with assist-control and pressure support noninvasive modes, in comparison with an historical control group. We did not find a significant difference in the success rate of the two modes, but compliance to noninvasive ventilation was better with pressure support. In the former study patients showing neurological signs and requiring mechanical ventilation were excluded, while in the last study patients were selected on the basis of necessity of mechanical ventilation. The fact that in the last study, ventilation was applied by face mask instead of nasal mask may have influenced results. Further efforts are required to determine whether non-invasive ventilation is more a preventive measure to avoid endotracheal intubation, or is another means of delivering ventilatory support.

Methacholine inhaled challenge: study of correlation among different indices expressing the result.

We tested measures of specific airway conductance (sGaw) and forced expiratory volume in one second (FEV1) versus transcutaneous oxygen tension (Ptc,O2) during inhaled methacholine bronchial challenge in 60 out-patients (38 males 22 females, mean age 33 +/- 13 yrs). The provocative doses of methacholine needed to produce a 35% decrease of sGaw (PD35,sGaw), a 20% fall in FEV1 (PD20,FEV1) and a 20% decrease in Ptc,O2 (PD20,O2) were simultaneously derived from the dose-response curves. Two groups were identified according to the PD20,FEV1 result ("responders" with a PD20,FEV1 < 2,000 micrograms methacholine and "nonresponders" with PD20,FEV1 > 2,000 micrograms methacholine). All three indices derived from the dose-response curves differed significantly between the groups (p < 0.00005). The relationship analysis showed a significantly better value for PD20,O2 versus PD35,sGaw (r = 0.98) than versus PD20, FEV1 (r = 0.62). We observed similar baseline levels and variations in arterial oxygen tension (Pa,O2) and Ptc,O2 during methacholine challenge (-25 and -27%, respectively) in 14 randomly studied responders. Thus, inhaled methacholine-induced hypoxaemia (PD20,O2) seems to reflect PD35,sGaw better than changes in FEV1. Our investigation supports the hypothesis that PD20,O2 could be useful in interpreting the methacholine inhaled challenge. It could be of help in clarifying the pathophysiological meaning of the concurrent hypoxaemia during this challenge, which should be further elucidated.

Cardiopulmonary intermediate intensive unit: time course of two years activity.

Intermediate intensive care may be defined as a post comprehensive programme, where monitoring, combined with necessary treatment, improves and maintains physiological functions to complete the cure of underlying diseases. The aims of this paper are: 1) to describe the caring activity that patients admitted to our 12 bed Cardiopulmonary Intermediate Intensive Unit (CPIIU) experience and, 2) to demonstrate that a noninvasive choice does not worsen mortality and the quality of care needed to improve patient outcome. From September 1st 1990 to September 30th 1992, 775 patients (135 respiratory subjects) were admitted. The majority of these patients came from Coronary Intensive Units or Medical and Surgical Intensive Care Units. Noninvasive cardiorespiratory monitoring was assessed in these patients, to obtain their clinical improvement. After this post acute observance, our patients were followed during a stabilization programme in the cardiopulmonary rehabilitation division until a day-hospital or home care programme was carried out. By implementing the CPIIU principles in our department we have reduced the number of deaths and the necessity for Intensive Care Unit admission (from 19 to 9.6%). The estimated risk of death proposed by Apache score was higher than that recorded in our patients (estimated Apache = 25 and 6% for respiratory and cardiac patients, respectively; actual Apache = 10.4 and 3.1% for the same patients, respectively). Average hospitalisation days in our CPIIU was 18 +/- 9. Our CPIIU showed a mean daily cost for each patient of $370.6.(ABSTRACT TRUNCATED AT 250 WORDS)

Professional figures in intermediate intensive units.

In Italy, respiratory intermediate intensive care units (IICUs) are not yet considered as autonomous hospital departments. The IICU of the Rehabilitation Department of the Medical Centre of Gussago (12 monitored beds) provides care for respiratory and cardiac patients. Ventilatory assistance and noninvasive modalities both in treatment and monitoring suggest a multidisciplinary approach to the patient. Highly professional figures should, therefore, be singled out to provide care in a respiratory IICU. The medical staff is composed of one anaesthesiologist, one cardiologist and one pulmonologist, who can integrate care when respiratory complications occur in a cardiological patient, or when cardiac events affect a respiratory patient. Nurses are capable of specific activities, especially when ventilatory assistance is required. The presence of a physiotherapist reduces the nursing workload, especially for ventilated individuals. The psychological aspect is undertaken by a specialist. Finally, an expert in nutrition provides an individualized dietary regimen. Our 4 year experience encourages such a multidisciplinary approach. An ideal integration of the professional activities should provide adequate and individual care for patients admitted to an IICU.

An unusual increase in haemodynamic values in a sleep apnoea syndrome patient with prolonged apnoea.

This case report shows the results of a right heart catheterisation in a patient with sleep apnoea syndrome (SAS). Arterial oxygen saturation (SaO2), heart rate, oronasal flow, and monitoring of electroencephalographic (EEG), sovrayoidal electromyographic (EMG) and thoracoabdominal movements were recorded simultaneously. A mixed apnoea of 180 s was registered, SaO2 fell to 54% and systolic pulmonary artery pressure (sPAP) increased to 130 mmHg. Slowly, haemodynamic values began to normalise with the reappearance of respiratory acts. We can hypothesize that this patient's nocturnal apnoeas may cause frequent and deep negative pleural pressure swings, with severe continuous action on pulmonary circulation. This case report has shown that a SAS patient is capable of developing an adaptative response to an unusual and remarkable systolic pulmonary artery pressure increase, which is mainly due to hypoxic vasoconstriction.

Hygroscopic condenser humidifiers in chronically tracheostomized patients who breathe spontaneously.

The aim of this study was to test the usefulness of hygroscopic condenser humidifiers on secretion and on inspired gas temperature in tracheostomized patients. Forty spontaneously breathing chronically tracheostomized patients were divided into two groups: Group 1 received a hygroscopic condenser humidifier connected to the tracheostomy, 24 h daily for 10 days; Group 2, without any protection system, was chosen as the control group. The daily number of tracheal suctions, quantity of aspirate and thickness and colouring of secretions was evaluated. At baseline, and at days 5 and 10, patients were submitted to blood gas analysis, respiratory function tests and sputum analysis. The temperature of gases breathed was measured at rest and during a hyperventilation test, with and without the hygroscopic condenser humidifier. Statistically significant differences were found in thickness and colouring of secretions between the two groups during the period of 10 days. Group 2 showed a significantly greater trend in number of bacteria than Group 1. The group with the hygroscopic condenser humidifier showed respiratory function improvement over time for forced expiratory volume in one second (FEV1) and tidal volume (VT), maximal inspiratory pressure (MIP), and maximal voluntary ventilation (MVV) in comparison to the control group, who did not. Significant differences in the temperature between rest and hyperventilation, with and without a hygroscopic condenser humidifier were also found. In conclusion, a hygroscopic condenser humidifier may be useful in chronically tracheostomized patients who breathe spontaneously, improving viscosity and colouring of secretions, preventing further bacterial colonization, heating inspiratory flow, and helping to improve the functional outcome.

Respiratory muscle function and exercise capacity in multiple sclerosis.

Patients with multiple sclerosis (MS) show a poor exercise tolerance. A reduction in respiratory muscle strength has also been reported. The purpose of this study was to evaluate whether reduction in exercise tolerance was related to respiratory muscle dysfunction. Twenty four multiple sclerosis patients (mean +/- SD age: 48 +/- 9 yrs, duration of illness 12.2 +/- 6 yrs, severity of illness as assessed by Expanded Disability Scale Score (EDSS) 5.3 +/- 2), underwent detailed evaluation of lung function tests, arterial blood gas analysis, respiratory muscle strength and endurance, and exercise test on an arm ergometer. Sixteen of the 24 patients were able to perform the exercise test (Group I), whilst the other eight were not (group II). Arterial blood gases and lung function tests were normal for both groups. Respiratory muscle strength as assessed both by maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) was significantly reduced (MIP 18-76 cmH2O; MEP 16-82 cmH2O) compared to predicted values. Inspiratory muscle endurance time was significantly reduced in Group II in comparison to Group I (247 +/- 148 vs 397 +/- 154 s, respectively). Both MIP and MEP were significantly related to inspiratory muscle endurance time. Endurance time, MIP and MEP were inversely significantly related to duration of illness, whilst only endurance time was significantly related to Expanded Disability Scale Score.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term effectiveness of pulmonary rehabilitation in patients with chronic airway obstruction.

The aim of this study was to evaluate the long-term outcome of an outpatient pulmonary rehabilitation programme (PRP) in patients with chronic airway obstruction (CAO). In 61 CAO patients (35 asthmatics and 26 chronic obstructive pulmonary disease (COPD)) lung and respiratory muscle function, exercise tolerance (by symptom limited cycloergometer and walking tests), dyspnoea (Borg scale, visual analogue scale (VAS), baseline and transitional dyspnoea index (BDI and TDI, respectively)) and quality of life (St George's Respiratory Questionnaire (SGRQ)) were assessed at baseline (to), at discharge (t1) and 12 months postdischarge (t2). Preprogramme and post-programme hospital admissions and exacerbations of disease were also recorded. In comparison with baseline, no significant change was observed in lung function tests in either diagnostic group, either at t1 or at t2. In both groups improvements in respiratory muscle strength, exercise tolerance, Borg scale and VAS reported at t1 were partially reduced at t2. Analysis of variance showed that these changes over time were similar in the two groups. Mean values of SGRQ and BDI/TDI improved at t1, and, unlike exercise tolerance, did not worsen at t2. However, a clinically relevant difference in SGRQ between t2 and to was reported only in 56% of asthmatics and 52% of COPD patients. Compared with the preceding 2 yrs, in the year following PRP, hospital admissions and disease exacerbations decreased significantly in both diagnostic groups. Regardless of diagnosis, patients with chronic airway obstruction who underwent an outpatient pulmonary rehabilitation programme maintained an improved quality of life 12 months postdischarge despite a partial loss of the improvement in exercise tolerance.