Multiple dimensions of cardiopulmonary dyspnea.

BACKGROUND: The current theory of dyspnea perception presumes a multidimensional conception of dyspnea. However, its validity in patients with cardiopulmonary dyspnea has not been investigated. METHODS: A respiratory symptom checklist incorporating spontaneously reported descriptors of sensory experiences of breathing discomfort, affective aspects, and behavioral items was administered to 396 patients with asthma, chronic obstructive pulmonary disease (COPD), diffuse parenchymal lung disease, pulmonary vascular disease, chronic heart failure, and medically unexplained dyspnea. Symptom factors measuring different qualitative components of dyspnea were derived by a principal component analysis. The separation of patient groups was achieved by a variance analysis on symptom factors. RESULTS: Seven factors appeared to measure three dimensions of dyspnea: sensory (difficulty breathing and phase of respiration, depth and frequency of breathing, urge to breathe, wheeze), affective (chest tightness, anxiety), and behavioral (refraining from physical activity) dimensions. Difficulty breathing and phase of respiration occurred more often in COPD, followed by asthma (R(2) = 0.12). Urge to breathe was unique for patients with medically unexplained dyspnea (R(2) = 0.12). Wheeze occurred most frequently in asthma, followed by COPD and heart failure (R(2) = 0.17). Chest tightness was specifically linked to medically unexplained dyspnea and asthma (R(2) = 0.04). Anxiety characterized medically unexplained dyspnea (R(2) = 0.08). Refraining from physical activity appeared more often in heart failure, pulmonary vascular disease, and COPD (R(2) = 0.15). CONCLUSIONS: Three dimensions with seven qualitative components of dyspnea appeared in cardiopulmonary disease and the components under each dimension allowed separation of different patient groups. These findings may serve as a validation on the multiple dimensions of cardiopulmonary dyspnea.

Validation of the Chinese version of the Functional Performance Inventory Short Form in patients with chronic obstructive pulmonary disease.

AIMS AND OBJECTIVE: To determine the reliability and validity of the Chinese version of the Functional Performance Inventory Short Form (FPI-SF-C) in patients with chronic obstructive pulmonary disease in Beijing, China. BACKGROUND: The Functional Performance Inventory Short Form (FPI-SF) is a 32-item instrument designed to measure self-reported functional performance of patients with chronic obstructive pulmonary disease. This instrument had not been translated into Mandarin Chinese and tested for use in mainland China. DESIGN: Cross-sectional validation study with a two-week test of reproducibility. METHOD: The FPI-SF was translated using forward and backward translation procedures and administered to 108 stable chronic obstructive pulmonary disease patients from outpatient clinics of three hospitals in Beijing, China. Pulmonary function and six-minute walking distance (6-MWD) tests were performed on the same day or within one week before the FPI-SF-C completion. Thirty of the patients participated in the reproducibility assessment. RESULTS: Cronbach's alpha for the FPI-SF-C total score was 0·89; subscales ranged from 0·70 (Body Care)-0·89 (Spiritual activities). Test-retest reliability (intraclass correlation coefficient) was 0·93 with subscales ranging from 0·73 (Body Care)-0·96 (Household Maintenance). No ceiling or floor effects were observed for total FPI-SF-C score. Total scores correlated significantly (p<0·05) with 6-MWD (r=0·56), modified Medical Research Council Dyspnoea Scale (MMRC) (r=-0·55), BODE index (r=-0·47), forced expiratory volume in one second (FEV(1)) (r=0·41) and FEV(1) % of predicted (r=0·26) and differentiated patients based on GOLD rating of COPD severity (χ(2)=16·22, p<0·001). CONCLUSIONS: Results suggest the FPI-SF-C is a reliable and valid instrument for measuring functional performance in mainland Chinese patients with chronic obstructive pulmonary disease. Further psychometric testing in a wide range of subjects and an evaluation of its utility in clinical practice are warranted. RELEVANCE TO PRACTICE: The FPI-SF-C may be useful for understanding difficulties in functional performance and evaluating the effect of treatment in Chinese patients with chronic obstructive pulmonary disease.

Scoliosis on pulmonary function / 中国医学科学院学报

Scoliosis is a common disease in children that causes deformity of spine and thoracic cage. The deformity not only affects the appearance, but also leads to irreversible impairment of lung function and respiratory failure in severe cases. This systematic review on publications over past 50 years demonstrates that scoliosis impairs growth and development of lungs, limits chest wall movement, and results in restrictive ventilation defect and gas exchange dysfunction. Respiratory failure occurs primarily in early-onset scoliosis and/or during latter half of gestation. Surgery corrects deformity and may slow down its progression. However, invasive procedure itself impairs lung function. Non invasive procedures prevent the deterioration of lung function rather than promoting growth and development of lungs. As a consequence, reserve of pulmonary function is recommended when surgical intervention is considered.

Spinal factors affecting pulmonary function in patients with scoliosis / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate pulmonary function impairment and the spinal factors that may determine pulmonary function in patients with scoliosis.</p><p><b>METHODS</b>Seventy-eight patients with idiopathic scoliosis or congenital scoliosis and 78 age- and gender-matched healthy subjects were enrolled in this study. The radiographic parameters of spinal deformity were obtained from patients with scoliosis. Both two groups received pulmonary function tests.</p><p><b>RESULTS</b>Patients with scoliosis demonstrated a restrictive pattern of pulmonary function impairment with a proportional decrease in both forced expiratory volume in one second and forced vital capacity. Total lung capacity and functional residual capacity were reduced. Carbon monoxide diffusion capacity was decreased, while diffusion coefficient remained normal or slightly higher. Airway resistance and conductance were not affected. In addition, airway resistance and residual volume were found abnormal in patients with congenital scoliosis. Multiple linear regression analysis showed that three spinal factors including involved thoracic vertebrae, vertical height from C7 to S1, and Cobb angle were independently responsible for 40%-51% of total variances of forced vital capacity, forced expiratory volume in one second, total lung capacity, and functional residual capacity.</p><p><b>CONCLUSIONS</b>Patients with scoliosis have restrictive ventilation defects. More thoracic vertebrae involvement, lower vertical height, and larger Cobb angle are associated with severer impairment of lung volume.</p>

[Reliability and validity of modified pulmonary functional status and dyspnea questionnaire in Chinese patients with chronic obstructive pulmonary disease].

OBJECTIVE: To determine the reliability and validity of the modified pulmonary functional status and dyspnea questionnaire (PFSDQ-M) Chinese version in patients with chronic obstructive pulmonary disease (COPD) at 2 hospitals in Beijing, China. METHODS: PFSDQ-M has three domains, i.e., change experienced by patient with activities or activity restriction (CA), dyspnea with activities (DA) and fatigue with activities (FA). Sixty-one patients with COPD in stable condition were assessed by interview with PFSDQ-M Chinese version, modified Medical Research Council dyspnea scale (MMRC), respectively, and underwent pulmonary function test (PFT) and 6-minute walking test (6MWT) on the same day or within one week before interview. RESULTS: Cronbach's alpha was 0.84, 0.85 and 0.89 for domains of CA, DA and FA of the PFSDQ-M, respectively. Scores of change in activities, dyspnea and fatigue with activities in patients of COPD correlated to their 6-minute walking distance (r = -0.39 to -0.50), FEV(1) (r = -0.28 to -0.36), FEV(1)/FVC (r = -0.27 to -0.37), FEV(1)% of predicted (r = -0.27 to -0.37), dyspnea score in MMRC (r = 0.59 to 0.66) and BODE index (r = 0.40 to 0.51), respectively (all P < 0.01). Degrees of restriction of activity, dyspnea and fatigue with activities varied significantly in patients with different severity of COPD (chi(2) = 7.35 to 15.21, P < 0.05, P < 0.01, respectively). CONCLUSIONS: Results of 61 patients with COPD interviewed with PFSDQ-M Chinese version suggest its good reliability and validity in discriminating patients with COPD of varied severity and stages.

[Diagnostic specificity of dynamic assessment and monitoring of spirometry in asthma].

OBJECTIVE: To evaluate the diagnostic specificity of dynamic assessment and monitoring using a portable spirometer in diagnosis and differential diagnosis of asthma. METHODS: We retrospectively reviewed the results of dynamic monitoring of spirometry in 145 symptomatic patients with physician-diagnosed asthma. Flow-volume curve and simultaneous symptoms and mood were measured in a fixed-time thrice-daily assessment schedule for 2 weeks. Patients were allowed to make additional measurements in case of symptom exacerbations. RESULTS: The clinical data of 51 males and 94 females with a mean age of (39.1 +/- 13.0) years (ranged from 10 to 65 years) were analyzed. Duration of asthma before study was (6.7 +/- 9.9) years. Of 145 patients with physician-diagnosed asthma, 126 (87%) could be conclusively confirmed for a diagnosis of asthma. Asthma was misdiagnosed in 14 patients (9.7%). Overdiagnosis of asthma was observed in 5 patients (3.4%). CONCLUSION: Dynamic assessment and monitoring using a portable spirometer by revealing variability and reversibility of airway obstruction may provide an additional tool for diagnosis and differential diagnosis of asthma.

Fearful imagery induces hyperventilation and dyspnea in medically unexplained dyspnea.

BACKGROUND: Medically unexplained dyspnea refers to a condition characterized by a sensation of dyspnea and is typically applied to patients presenting with anxiety and hyperventilation without underlying cardiopulmonary pathology. We were interested to know how anxiety triggers hyperventilation and elicits subjective symptoms in those patients. Using an imagery paradigm, we investigated the role of fearful imagery in provoking hyperventilation and in eliciting symptoms, specifically dyspnea. METHODS: Forty patients with medically unexplained dyspnea and 40 normal subjects matched for age and gender were exposed to scripts and asked to imagine both fearful and restful scenarios, while end-tidal PCO(2) (PetCO(2)) and breathing frequency were recorded and subjective symptoms evaluated. The subject who had PetCO(2) falling more than 5 mmHg from baseline and persisting at this low level for more than 15 seconds in the imagination was regarded as a hyperventilation responder. RESULTS: In patients with medically unexplained dyspnea, imagination of fearful scenarios, being blocked in an elevator in particular, induced anxious feelings, and provoked a significant fall in PetCO(2) (P < 0.05). Breathing frequency tended to increase. Eighteen out of 40 patients were identified as hyperventilation responders compared to 5 out of 40 normal subjects (P < 0.01). The patients reported symptoms of dyspnea, palpitation or fast heart beat in the same fearful script imagery. Additionally, PetCO(2) fall was significantly correlated with the intensity of dyspnea and palpitation experienced during the mental imagery on one hand, and with anxiety symptoms on the other. CONCLUSIONS: Fearful imagery provokes hyperventilation and induces subjective symptoms of dyspnea and palpitation in patients with medically unexplained dyspnea.

[Clinical application of portable spirometry in asthma].

OBJECTIVE: To investigate the clinical applications of portable spirometry in asthma. METHODS: Twenty patients with asthma were recruited from Peking Union Medical College Hospital. Flow-volume loop, simultaneous asthma symptoms, and mood were monitored three times a day for consecutive 14 days. RESULTS: In patients with a normal daytime spirometry, marked decline of forced expiratory volume in one second (FEV1) and peak expiratory flow (PEF) were observed at night and/or in the early morning. A within subject correlation analysis between FEV1, PEF, and asthma symptoms showed that the correlation between symptoms and airway obstruction was found only in seven out of twenty patients (35%). Four patients (20%) reported many symptoms with nearly normal portable spirometry. Accordingly, their symptoms were not correlated with FEV1 and PEF. This group of patients was defined as over-perceivers. On the contrary, another two patients (10%) did not report any symptoms while obvious airways obstruction was recorded by a portable spirometry. These patients were defined as under-perceivers. CONCLUSIONS: Dynamic monitoring of flow-volume loop with a portable spirometry is more accurate than routine lung function test in assessment of asthma severity. In addition, combined with simultaneous monitoring of symptoms, it would be of particularly helpful in identifying two specific types of asthma patients, e.g. over-perceivers and under-perceivers.

[Medically unexplained dyspnea in children: a review of 34 cases].

OBJECTIVE: Medically unexplained dyspnea is common in adult and accounts for 14% patients complaining of dyspnea. Its occurrence in children is seldom recognized. In the present paper, 34 children with medically unexplained dyspnea (age 10 to 18 years) seen in Peking Union Medical College Hospital from 1996 to 2002 are reported. METHODS: The diagnosis of medically unexplained dyspnea was clinical: it was based on the presence of dyspnea and other complaints which cannot be explained by an organic disease. The patients answered Nijmegen questionnaire and state and trait anxiety (STAI), and performed hyperventilation provocation test. Twenty sessions of breathing therapy were applied and 13 out of 34 children were followed up after the therapy. RESULTS: Among the children, 75% started to have symptoms at the age of 13 to 16 years, though the age of first episode could be as early as 8 years. In most of the cases, the course was chronic clinically. In addition to marked dyspnea, their clinical profile included symptoms of hyperventilation i.e. blurred vision, dizziness, tingling, stiff fingers or arm. The symptoms of anxiety were less frequent in children and accordingly the level of anxiety evaluated by means of STAI was lower in children compared to adult patients. The precipitating psychological factors appeared to be related to middle school competition. Pressure from exams, reprimand from stern and unsympathetic teachers coupled with high parental expectation could be emotionally damaging to psychologically susceptible children. Thirteen patients were followed up after 2-3 months of breathing therapy with emphasis on abdominal breathing and slowing down of expiration. After therapy, the sum score of the Nijmegen Questionnaire was markedly decreased. Dyspnea and symptoms of hyperventilation were improved. The level of anxiety was minimally modified. CONCLUSION: The cases illustrated the need for careful diagnostic evaluation and treatment because of the high rate of chronicity of the disorder.

[Diagnosis and treatment of medically unexplained dyspnea].

Medically unexplained dyspnea refers to a group of patients presenting marked dyspnea without structural alterations of organs/systems after thorough examinations. This clinically neglected group of patients accounts for about 14% of patients with dyspnea in secondary health care. They appear very difficult to manage clinically. In this paper an organized approach used to diagnose medically unexplained dyspnea is presented. Breathing re-training is recommended as a therapy for those "difficult to treat patients".

Medically unexplained dyspnea: psychophysiological characteristics and role of breathing therapy.

BACKGROUND: Medically unexplained dyspnea occurs commonly in medical settings and remains poorly understood. This study was conducted to investigate the psychophysiological characteristics of medically unexplained dyspnea and the efficacy of breathing retraining for these patients. METHODS: A group of patients with medically unexplained dyspnea were compared to patients with a variety of organic lung diseases and healthy subjects. In another group of patients, the influence of breathing therapy on complaints, anxiety, and breath-holding was evaluated for an average of 1.5 years. RESULTS: Patients with medically unexplained dyspnea reported more intense dyspnea than patients with a variety of organic lung diseases. Additionally, they were anxious and presented a broad range of symptoms in daily life and under challenge, for instance voluntary hyperventilation. More than one third of them qualified for panic disorder. They had shorter breath-holding time at rest, less increase in breath-holding time and higher chances of showing a "paradoxical" decrease of breath-holding time after hyperventilation. A combination of PaO2, forced expiratory volume in one second (FEV1), and anxiety measures distinguished them from organic dyspnea. Breathing retraining profoundly improved their symptoms and decreased the level of state and trait anxiety. Moreover, they better tolerated the voluntary hyperventilation and the symptoms induced were also markedly decreased after therapy. Breath-holding time was prolonged and PetCO2 in a representative group of patients increased. CONCLUSIONS: Patients with medically unexplained dyspnea appear to have the feature of a "psychosomatic" patient: an anxious patient with a wide variety of symptoms of different organ systems that do not have an organic basis. They can be distinguished from organic dyspnea using a small set of physiological and psychological measures. Breathing retraining turns out to be an effective therapy for those "difficult to treat patients".

[Assessment of pulmonary function in SARS patients during the convalescent period].

OBJECTIVE: To investigate the pulmonary function in severe acute respiratory syndrome (SARS) patients during the convalescent period. METHODS: Followup 89 outpatients of SARS. The follow-up study included interview, physical examination, and pulmonary function test. RESULTS: The interval between hospital discharge and functional assessment was 1.75 +/- 0.53 months (0.5-3.4 months). Mild to moderate abnormalities in pulmonary function were found in 48 patients (53.9%). Diffusion capacity for carbon monoxide (DLco) was impaired in 38 patients (42.7%); in 7 patients (7.9%), lung function was restrictive defect combined DLco impairment; Other patterns of impairment were revealed in 3 patient. Dyspnea during acute phase and CT during the convalescent period were found to have significant influences on DLco and total lung capacity (TLC). CONCLUSIONS: Diffusing capacity impairment as well as restrictive defect persist in convalescence SARS.

[Role of single-breath carbon monoxide-diffusing capacity in monitoring the bleomycin-induced lung toxicity in human].

OBJECTIVE: To investigate if the carbon monoxide-diffusing capacity (D(LCO)) could be the early indictor monitoring the bleomycin-induced lung toxicity (BILT) with retrospection of the influence of bleomycin cumulative dose on the pulmonary functions. METHODS: During June 1985 to October 2000, 42 patients with malignant tumor of ovarian germ cells received chemotherapy containing bleomycin in the department of Obstetrics and Gynecology of Peking Union Medical College Hospital. Twenty three patients (54.76%) among them had >or= 2 courses of chemotherapy with bleomycin and performed >or= 2 measurements of lung function. These 23 patients were included in the study. The forced expiratory volume in one second (FEV(1)), forced vital capacity (FVC), total lung capacity (TLC) and D(LCO) were measured and recorded as % of predicted. The D(LCO) was corrected by hemoglobin concentration [D(LCO) corrected = D(LCO) measured x (9.38 + Hb) divided by (1.76 x Hb)]. All the data were divided into 4 groups according to the cumulative dose of bleomycin (pre-treatment group, < 100 mg group, 101 - 200 mg group and > 201 mg group). The relationship between D(LCO) and bleomycin cumulative dose was examined by linear regression analysis and t-test. RESULTS: The values of FEV(1%)predicted in the 4 groups were 99.83 +/- 16.41 (14), 101.43 +/- 12.32 (42), 99.41 +/- 10.22 (23), and 90.96 +/- 13.63 (12), respectively. The FVC%predicted were 97.74 +/- 18.23 (14), 101.11 +/- 13.95 (42), 96.49 +/- 12.04 (23) and 89.63 +/- 18.20 (12), respectively. The TLC%predicted were 101.22 +/- 10.68 (13), 106.14 +/- 12.16 (40), 102.13 +/- 11.33 (23) and 95.05 +/- 14.06 (11), respectively. There were no statistical significant differences in the parameters among the 4 groups. The D(LCO%)predicted of the 4 groups were 93.27 +/- 12.75 (14), 94.51 +/- 12.50 (40), 80.93 +/- 10.05 (24) and 70.99 +/- 11.69 (15), respectively, and the D(LCO) of the last group (> 201 mg group) was significantly decreased as compared to that of the other groups (P < 0.05). A bleomycin dose-related fall in D(LCO) was observed, y = 100.59 - 0.11x, r = -0.649, P < 0.001. CONCLUSION: The D(LCO) might be the most sensitive indicator of subclinical BILT. However, the cumulative dose of bleomycin did not show significant influence on the FEV(1), FVC and TLC.