Impairment Of Ventilatory Function Research Articles

Understanding the Link Between Adult Asthma and Coronary Artery Disease: A Narrative Review.

Asthma is a common pathology worldwide that occurs due to chronic inflammation of the respiratory airways. Persistent pulmonary inflammation leads to low-grade systemic inflammation, influencing blood vessels and triggering coronary artery disease (CAD) events. This review's objectives include discussing the susceptible population for CAD, the mechanism underlying CAD creation in asthma patients, the characteristics of asthma, and the influence of anti-asthmatic medications on CAD development. Adult-onset asthma is strongly linked to CAD and stroke. Future research may shed light on these disparities. Atherosclerosis and asthma are linked through both intrinsic and extrinsic pathways, with inflammation being the intrinsic pathway and hypoxia and tachyarrhythmia being the extrinsic pathways. The most probable mechanisms for increased coronary vasospastic angina (CVsA) incidence in asthmatic patients are vascular smooth muscle cell hypercontraction and endothelial dysfunction. Studies have shown a dose-response relationship between asthma control and myocardial infarction (MI) risk, with uncontrolled asthma at the highest risk. Impairment of ventilatory function is a distinct risk factor for lethal MI and cardiovascular death (CVD). The use of beta-2-agonists and chronic oral glucocorticoid therapy in severe asthmatics has been linked to increasing the risk for CAD. However, some studies have shown that the risk of MI among patients with active asthma is not related to the use of asthma medications. Further research is needed to determine the involvement of adult asthma features and their treatments in the development of CAD.

Society of Anesthesia and Sleep Medicine Position Paper on Patient Sleep During Hospitalization.

This article addresses the issue of patient sleep during hospitalization, which the Society of Anesthesia and Sleep Medicine believes merits wider consideration by health authorities than it has received to date. Adequate sleep is fundamental to health and well-being, and insufficiencies in its duration, quality, or timing have adverse effects that are acutely evident. These include cardiovascular dysfunction, impaired ventilatory function, cognitive impairment, increased pain perception, psychomotor disturbance (including increased fall risk), psychological disturbance (including anxiety and depression), metabolic dysfunction (including increased insulin resistance and catabolic propensity), and immune dysfunction and proinflammatory effects (increasing infection risk and pain generation). All these changes negatively impact health status and are counterproductive to recovery from illness and operation. Hospitalization challenges sleep in a variety of ways. These challenges include environmental factors such as noise, bright light, and overnight awakenings for observations, interventions, and transfers; physiological factors such as pain, dyspnea, bowel or urinary dysfunction, or discomfort from therapeutic devices; psychological factors such as stress and anxiety; care-related factors including medications or medication withdrawal; and preexisting sleep disorders that may not be recognized or adequately managed. Many of these challenges appear readily addressable. The key to doing so is to give sleep greater priority, with attention directed at ensuring that patients' sleep needs are recognized and met, both within the hospital and beyond. Requirements include staff education, creation of protocols to enhance the prospect of sleep needs being addressed, and improvement in hospital design to mitigate environmental disturbances. Hospitals and health care providers have a duty to provide, to the greatest extent possible, appropriate preconditions for healing. Accumulating evidence suggests that these preconditions include adequate patient sleep duration and quality. The Society of Anesthesia and Sleep Medicine calls for systematic changes in the approach of hospital leadership and staff to this issue. Measures required include incorporation of optimization of patient sleep into the objectives of perioperative and general patient care guidelines. These steps should be complemented by further research into the impact of hospitalization on sleep, the effects of poor sleep on health outcomes after hospitalization, and assessment of interventions to improve it.

Hypersensitivity pneumonia diagnosed by excisional lung biopsy: a clinicopathological features of 47 cases

Objective: To analyze the clinicopathological and immunohistochemical characteristics of the hypersensitivity pneumonia (HP) cases that were diagnosed by excisional lung biopsy, to improve the diagnosis accuracy of HP. Methods: The data of 47 HP cases diagnosed by excisional lung biopsy during the last 20 years were collected in Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, from January 2000 to June 2020. The clinicopathological features and the immunohistochemical profiles of CD3, CD4, CD8 and CD20 were analyzed using light microscopy and immunohistochemical stains. Results: The age of the patients ranged from 15 to 68 years, while the ratio of male to female was 22∶25. The main symptoms were shortness of breath and cough, and 32 cases had a history of allergen exposure. Most of the patients had restrictive impaired ventilatory function, and impaired diffusion function. The proportion of lymphocytes in bronchoalveolar lavage fluid (BALF) increased in 85.3%(29/34) of the patients, and the CD4+/CD8+ T cell ratio was not higher than 0.8 in 31.3%(10/32) of the patients. Microscopically, 59.6%(28/47) of the cases showed nonnecrotizing granuloma/giant cells in the stroma, and 40.4% (19/47) of the cases had only giant cells. Ninety-three-point six percent of the cases(44/47) had peribronchiolar metaplasia, while 70.2%(33/47) had focal cell-rich inflammation. Forty-four cases (93.6%, 44/47) had fibrosis, which was manifested as usual interstitial pneumonia-like fibrosis (47.7%, 21 cases), nonspecific interstitial pneumonia-like fibrosis (29.5%, 13 cases), purely peribronchiolar fibrosis (6.8%, 3 cases) and mixed fibrosis (15.9%, 7 cases). Immunohistochemistry showed that CD4+ T cells were fewer than CD8+ T cells in 24 cases (55.8%, 24/43) of HP. Thirty-two HP patients had follow-up data. Among them, 7 patients had improved symptoms, 12 patients were stable, and 13 patients had worsening symptoms. Conclusions: The most common type of HP diagnosed by excisional lung biopsy is chronic HP. The clinical characteristics are long course of disease, restricted ventilation disorder and impaired diffusion function with the increase of lymphocyte proportion in BALF. Nearly 1/3 of the patients have no known history of allergen contact. The degree of fibrosis in HP patients diagnosed by excisional lung biopsy is severe, and the histologic types of fibrosis varies, but the UIP-like and/or NSIP-like fibrosis is most common. The CD4+/CD8+ T cell ratio in lung tissues is less than 1 in more than half of the cases. Pulmonary fibrosis continued to increase in some of the patients with chronic HP, even after treatment.

Immobilization quality and cardiopulmonary effects of etorphine alone compared with etorphine–azaperone in blesbok (Damaliscus pygargus phillipsi)

ObjectiveTo evaluate the immobilization quality and cardiopulmonary effects of etorphine alone compared with etorphine–azaperone in blesbok (Damaliscus pygargus phillipsi). Study designBlinded, randomized, crossover design. AnimalsA total of 12 boma-habituated female blesbok weighing [mean ± standard deviation (SD)] 57.5 ± 2.5 kg. MethodsEach animal was administered etorphine (0.09 mg kg–1) or etorphine–azaperone (0.09 mg kg–1; 0.35 mg kg–1) intramuscularly with 1-week intertreatment washout period. Time to first sign of altered state of consciousness and immobilization time were recorded. Physiological variables were recorded, arterial blood samples were taken during a 40-minute immobilization period, and naltrexone (mean ± SD: 1.83 ± 0.06 mg kg–1) was intravenously administered. Recovery times were documented, and induction, immobilization and recovery were subjectively scored. Statistical analyses were performed; p < 0.05 was significant. ResultsNo difference was observed in time to first sign, immobilization time and recovery times between treatments. Time to head up was longer with etorphine–azaperone (0.5 ± 0.2 versus 0.4 ± 0.2 minutes; p = 0.015). Etorphine caused higher arterial blood pressures (mean: 131 ± 17 versus 110 ± 11 mmHg, p < 0.0001), pH, rectal temperature and arterial oxygen partial pressure (59.2 ± 7.7 versus 42.2 ± 9.8 mmHg), but lower heart (p = 0.002) and respiratory rates (p = 0.01). Etorphine–azaperone combination led to greater impairment of ventilatory function, with higher end-tidal carbon dioxide (p < 0.0001) and arterial partial pressure of carbon dioxide (58.0 ± 4.5 versus 48.1 ± 5.1 mmHg). Immobilization quality was greater with etorphine-azaperone than with etorphine alone (median scores: 4 versus 3; p < 0.0001). Conclusions and clinical relevanceBoth treatments provided satisfactory immobilization of blesbok; however, in addition to a deeper level of immobilization, etorphine–azaperone caused greater ventilatory impairment. Oxygen supplementation is recommended with both treatments.

RESPIRATORY MORBIDITY AND VENTILATORY FUNCTION IMPAIRMENT AMONG CEMENT FACTORY EMPLOYEES

Background: Cement is one of the most important building materials of the world. More than 250 000 people work in concrete manufacturing. Cement factory workers are exposed to dust during various manufacturing and production process, such as quarrying and handling of raw materials.&#x0D; Methods: This cross sectional study aims at determining the prevalence of respiratory morbidity and ventilatory function impairment among the cement factory employees and the use of personal protective equipment (PPE).&#x0D; Results: The mean age was 33.8±11.4 and most of them belonged to 21-30 age groups. The major respiratory symptoms were shortness of breath (18%), coughing out phlegm (22%), coughing that wakes up in the morning (14%) and wheezing (6%).Though study had its focus on respiratory morbidity, a significant proportion of the workers had other chronic non communicable diseases including diabetes (37%), blood pressure (10%) and cardio-vascular diseases/symptoms (26.6%). Conclusion: Though everyone was aware about the PPE some lacked the use of it due to discomfort leading to lung function impairment. The percentage predicted lung volumes and the respiratory symptoms helped to create awareness about the use of PPE and using proper ventilation systems, to protect the workers from developing chronic respiratory diseases in future.&#x0D; Keywords: Cement factory workers, respiration, morbidity

Lung function abnormalities among garri processing workers in Ogbomoso, Nigeria.

Local production of garri (cassava crisps) is associated with air pollution and consequently lung function abnormalities among garri processing workers. This study was aimed at describing lung function abnormalities among Nigerians engaged in cassava crisps (garri) processing. A total of 351 workers and 351 controls were recruited at garri factories in Ogbomoso, Nigeria by multistage random sampling technique. Lung functional abnormalities were defined according to standardised European Respiratory Society/American Thoracic Society guidelines. Data analysis was performed using the IBM SPSS statistics version 22.0. The mean age of patients was similar to that of controls (41.7 ± 14.9 vs. 41.6 ± 14.7 yearsP = 0.960). Larger proportion (46.2%) of cassava crisps factory workers had abnormal ventilatory function parameters compared to 6.8% in controls (P < 0.001). The mean peak expiratory flow among garri factory workers was significantly lower than that of the controls; 268.25 ± 86.20 versus 349.04 ± 97.21 (L/min) (P < 0.001), likewise the mean forced vital capacity (FVC) (litres) and forced expiratory volume (FEV1) (litres) of garri factory workers and controls were significantly lower than those of the controls; 2.55 ± 1.07 versus 2.87 ± 0.79 (P < 0.001) and 2.00 ± 0.76 versus 2.41 ± 0.83 (P < 0.001) with FEV1/FVC ratio of 0.82 ± 0.16 versus 0.87 ± 0.06 (P < 0.001), respectively. The restrictive pattern of ventilatory functional abnormality was predominant among garri factory workers, 92 (26.2%). Sixty-two (17.7%) and 8 (2.3%) of garri factory workers had an obstructive and mixed pattern of ventilatory function abnormalities, respectively. Garri processing workers had significant ventilatory function impairment. Preventive strategies should be encouraged to reduce occupational hazards associated with garri processing in Nigeria.

Use of 'ideal' alveolar air equations and corrected end-tidal PCO2 to estimate arterial PCO2 and physiological dead space during exercise in patients with heart failure.

Arterial CO2 tension (PaCO2) and physiological dead space (VD) are not routinely measured during clinical cardiopulmonary exercise testing (CPET). Abnormal changes in PaCO2 accompanied by increased VD directly contribute to impaired exercise ventilatory function in heart failure (HF). Because arterial catheterization is not standard practice during CPET, this study tested the construct validity of PaCO2 and VD prediction models using 'ideal' alveolar air equations and basic ventilation and gas-exchangegas exchange measurements during CPET in HF. Forty-seven NYHA class II/III HF (LVEF=21±7%; age=55±9years; male=89%; BMI=28±5kg/m2) performed step-wise cycle ergometry CPET to volitional fatigue. Breath-by-breath ventilation and gas exchange were measured continuously. Steady-state PaCO2 was measured at rest and peak exercise via radial arterial catheterization. Criterion VD was calculated via 'ideal' alveolar equations, whereas PaCO2 or VD models were based on end-tidal CO2 tension (PETCO2), tidal volume (VT), and/or weight. Criterion measurements of PaCO2 (38±5 vs. 33±5mmHg, P<0.01) and VD (0.26±0.07 vs. 0.41±0.15L, P<0.01) differed at rest vs. peak exercise, respectively. The equation, 5.5+0.90×PETCO2-0.0021×VT, was the strongest predictor of PaCO2 at rest and peak exercise (bias±95%LOA=-3.24±6.63 and -0.98±5.76mmHg; R2=0.57 and 0.75, P<0.001, respectively). This equation closely predicted VD at rest and peak exercise (bias±95%LOA=-0.03±0.06 and -0.02±0.13L; R2=0.86 and 0.83, P<0.001, respectively). These data suggest predicted PaCO2 and VD based on breath-by-breath gas exchange and ventilatory responses demonstrate acceptable agreement with criterion measurements at peak exercise in HF patients. Routine assessment of PaCO2 and VD can be used to improve interpretability of exercise ventilatory responses in HF.

Structural and functional ventilatory impairment in infants with severe bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is the most frequent serious complication in preterm infants. We aimed to describe lung structure and ventilatory function of preterm infants with severe BPD and explored the association between early postnatal growth and these outcomes. We included preterm infants born ≤32 weeks gestational age (GA) with severe BPD. Lung structure was assessed on chest CT with the PRAGMA-BPD scoring system and ventilatory function by polysomnography (PSG) at 6 months corrected age. Postnatal growth was assessed by weight measured at birth, and at 2 and 6 months corrected age. We included 49 infants (median [IQR] GA of 25.7 [24.6-26.3] weeks and mean [SD] birth weight of 760 [210] g). A 95.5% of the chest CT scans showed architectural distortion of the lung, and an oxygen desaturation index (ODI) >5 was found in 74% of the infants. An increase in GA of 1 week was associated with higher total and normal lung volume (β coefficient [95% CI]: 1.86 [0.15, 3.57] and 2.03 [0.41, 3.65]), less hypoattenuation (-4.3 [-7.70, -0.90]%) and lower ODI (-36.7 [-64.2, -9.10]%). Higher weight at 6 months was independently associated with higher total and normal lung volume, and with less severe desaturations. Increased weight gain between 2 and 6 months of corrected age was associated with less severe desaturations during sleep (β coefficient [95% CI]: 2.09 [0.49, 3.70]). Most preterm infants with severe BPD have structural lung abnormalities and impaired ventilatory function early in life, partly explained by birth characteristics and infant growth.

Abstract 19397: Factors Affecting Exercise Capacity in Diabetic Heart Failure Patients

Background: Exercise intolerance is a key feature of chronic heart failure (CHF). CHF patients with concomitant diabetes (CHF-DM) have heightened exercise intolerance, poorer prognosis and worse symptoms. Causative mechanisms may be impaired ventilatory, cardiac or skeletal muscle function. We prospectively assessed factors affecting exercise capacity in CHF and CHF-DM. Methods: Stable CHF (n=33) and CHF-DM (n=33) patients with left ventricular systolic dysfunction (ejection fraction (EF) &lt;50%; NYHA class I-II; optimal device and medical therapy), were matched for age (mean±SD: 76±7 yr), weight (85±13 kg), height (1.72±0.06 m), systolic function (EF: 38±11%) and diastolic function (EA ratio 0.9±0.2). They underwent peak cardiopulmonary exercise testing with breath-by-breath pulmonary gas exchange analysis. Exertional shortness of breath (S) symptoms were recorded using the standardized Borg 0-10 scale. Continuous variables were reported as means (SD) and analysed using ANCOVA, categorical variables were analysed using the chi-squared test. A p-value of &lt; 0.05 was taken as significant. Results: CHF-DM had reduced exercise capacity (pVO2 13.9±4.3 v 17.5±5.9 ml/kg/min; p=0.01) and lower exercise time (354±209 v 511±250s; p=0.01). Cardiac and ventilatory responses did not differ: Heart rate rise (44±5 v 46±4 bpm; p=0.21), Ve/VCO2 (37.2±9.4 v 39.5±10.5; p=0.35), peak respiratory frequency (31.7± 6.7 v 31.1± 7.6 breaths/min; p=0.76). Symptoms did not differ at baseline, peak or during exercise (Peak Borg S: 4±2 v 4±2; p= 0.73) The lactate threshold (LT) (9.86±0.27 v 11.26 ±0.32 L/min; p=0.48), time to LT (358 ± 92.58 v 393 ± 203.94 s; p=0.22) and the respiratory compensation point (RCP) (12.77±0.37 v 14.37± 0.45 L/min; p=0.64) did not differ. Conclusion: Exercise capacity is reduced in CHF-DM subjects matched for age, BMI and cardiac function. There are no differences in symptoms of breathlessness, Ve/VCO2 slope or respiratory rate. However, LT and time to LT is unchanged, despite lower exercise time overall. Thus, there is an inability to tolerate exercise beyond the LT. This is likely due to altered skeletal mitochondrial function in the context of concomitant diabetes.

Regional Analgesia in Intensive Care Unit

Regional Analgesia in Intensive Care Unit

The relationship between regular second-hand smoke exposure at home and indictors of lung function in healthy school boys in Khartoum

BackgroundExposure to second-hand tobacco smoke at home has been linked to many complications, including impaired lung ventilatory function; however, there is great variation in intensity of this complication between individuals...

Reduced Confounding by Impaired Ventilatory Function With Oxygen Uptake Efficiency Slope and VE/VCO2 Slope Rather Than Peak Oxygen Consumption to Assess Exercise Physiology in Suspected Heart Failure

Heart failure and ventilatory disease often coexist; both create abnormalities in cardiopulmonary exercise test measurements. The authors evaluated the relative dependency of a well-recognized index of heart failure, peak oxygen consumption (VO(2)), and 2 newer indices, the minute ventilation (VE)/carbon dioxide production (VCO(2)) slope and oxygen uptake efficiency slope (OUES), on standard markers of impaired cardiac and ventilatory function. One hundred twenty-four patients (median age, 65.8; range, 22.6-84.9), with functional limitation from clinical heart failure were exercised. Peak VO(2) was 17.14 ± 7.58 mL/kg/min, VE/VCO(2) slope 50.1 ± 20.1, OUES 1.46 ± 0.68 L/min, and forced expiratory volume in 1 second (FEV(1) ) 1.88 ± 0.75 L. Peak VO(2) is substantially more sensitive to FEV(1) than ejection fraction (4.0 mL/kg/min difference between above- and below-median FEV(1) and 1.5 mL/kg/min between above- and below-median ejection fraction). OUES does not share this peculiar excess sensitivity to FEV(1) (0.12 L/min difference between above- and below-median FEV(1) and 0.01 L/min between above- and below-median ejection fraction). VE/VCO(2) slope has a borderline effect by FEV(1) (7.07 difference between above- and below-median FEV(1) and 2.07 between above- and below-median ejection fraction). Although widely used as a marker of heart failure severity, peak VO(2) is very sensitive to spirometry status and is indeed more affected by FEV(1) than by ejection fraction. OUES in contrast does not show this preferential sensitivity to impaired FEV(1).

General assessment of impaired ventilatory function by means of principal component analysis (author's transl)

General assessment of impaired ventilatory function by means of principal component analysis (author's transl)

Letter: The Relationship between Lung Function and Metabolic Syndrome in Obese and Non-Obese Korean Adult Males (Korean Diabetes J 2010;34:253-60)

The association between type 2 diabetes mellitus and impaired ventilatory lung function has been well documented in many studies [1-3]. One of the most important mechanisms underlying the association between type 2 diabetes mellitus and impaired lung function has been thought to be insulin resistance [4,5]. In Caucasians, forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) have been significantly associated with homeostasis model assessment of insulin resistance (HOMA), the marker of insulin resistance [4,5]. Metabolic syndrome (MetS) is a disease characterized by insulin resistance [6], suggesting that MetS might be associated with lung function. Kim et al. [7] showed that FVC values were significantly lower in a MetS group of Korean adult male subjects compared with those of the non-MetS group. In their study, the HOMA index was independently associated with FVC in multi-linear regression analysis after adjusting for age, height, and MetS components [7], consistent with the results of previous studies [4,5]. However, in the present study, the MetS group was significantly older than the non-MetS group, and age is a very important determining factor in lung function. I wonder whether the MetS group had lower FVC or FEV1 than did the age-matched non-MetS group. In addition, the pulmonary function test using a spirometer is composed of forced inspiration and expiration, and the forced inspiration is affected by respiratory muscle power. The decrease in muscle mass often found in subjects with insulin resistance results in muscle weakness and decreases in FVC and FEV1 [8]. The independent association between insulin resistance and FVC in this study may have been confounded by muscle mass; thus, further consideration of muscle mass is needed. The elderly population is growing very rapidly in Korea. This study is important to understand the association between MetS and lung function in the Korean population and indicates the importance of MetS management for preservation of pulmonary function, one of the important determinants of comorbidity in the elderly population.

Respiratory Symptoms and Pulmonary Function Impairment among Detergent Plant Workers in Jos, Northern Nigeria

The industrial process of detergent production could be deleterious to lung function. This study describes respiratory symptoms and ventilatory function impairment among detergent workers in Jos, Northern Nigeria. Two hundred detergent plant workers and controls were studied for the presence of respiratory symptoms and ventilatory function impairment using the MRC questionnaire and Spirometry. A significantly higher proportion of exposed detergent workers 178 (87.0%) reported respiratory symptoms compared to 52 (26.0%) controls [OR=23; 95% CI=12.9-41.3] (P<0.001). Commonest symptoms include rhinitis (57.5% versus 11.0%) and cough (48.5% versus 15%). Symptoms were most prevalent in the packaging section. FEV1, FVC and PEFR were significantly reduced among exposed detergent workers. Similarly, the predicted values of PEFR, FVC and FEV1, were significantly reduced among smokers (P<0. 001). Respiratory symptoms are highly prevalent among detergent workers. This was associated with impaired pulmonary function. Protective equipment and periodic lung function tests could reduce these effects.

Respiratory Effects of Household Exposures to Tobacco Smoke and Gas Cooking

The records of 1,724 residents of Washington County, Maryland, who had participated in 2 studies of respiratory symptoms and ventilatory function were analyzed to evaluate the effects of exposures at home to tobacco smoke generated by other members of their households and to fumes from the use of gas as a cooking fuel. Currently smoking subjects showed the highest frequency of respiratory symptoms and impaired ventilatory function; former smokers showed a lower frequency of these findings; and persons who had never smoked had the lowest prevalence of abnormal respiratory findings. The presence of a smoker in the household other than the subject was not associated with the frequency of respiratory symptoms, and only suggestively associated with evidence of impaired ventilatory function. The use of gas for cooking was related to an increased frequency of respiratory symptoms and impaired ventilatory function among men, being most marked among men who had never smoked. There was no evidence that cooking with gas was harmful to women.

Impairment of lung function in asbestos-exposed workers in relation to high-resolution computed tomography

The aim of the study was to determine the causes of impairment of ventilatory function and diffusing capacity in smoking asbestos-exposed workers (N=590) showing radiological pleural thickenings or pulmonary fibrosis. High-resolution computed tomography (HRCT) and spirometry were performed, and diffusing capacity was measured. The workers were divided into five groups based on the HRCT scoring: pleural disease (N=190), pulmonary fibrosis (N=68), emphysema (N=148), combined fibrosis and emphysema (N=74), and marked adhesions (N=110). The graded lung function impairment was compared between the groups. Moderate impairment of forced expiratory volume in 1 second [odds ratio (OR) 2.72, 95% confidence interval (95% CI) 1.31-5.57] and forced vital capacity (OR 2.81, 95% CI 1.05-6.89) was associated with the persons with combined fibrosis and emphysema. Marked impairment of diffusing capacity was associated with the combined fibrosis and emphysema (OR 4.94, 95% CI 2.48-9.77) but not with pleural disease (OR 0.21, 95% CI 0.09-0.45) or pulmonary fibrosis (OR 0.36, 95% CI 0.08-1.05). For the persons with combined fibrosis and emphysema, the mean fibrosis score did not differ between normal, slightly reduced, or markedly reduced diffusing capacity, but the emphysema score was significantly higher for the patients with marked impairment than for those with normal diffusing capacity (P < 0.01). Different profiles of asbestos- and smoking-induced pulmonary or pleural disease were found. The results indicate that the most important factor determining the degree of functional impairment in smoking asbestos-exposed workers is the presence of pulmonary emphysema.

Re: Cement Dust Exposure and Ventilatory Function Impairment: An Exposure-Response Study

HSE Division; ADMA-OPCO; Abu Dhabi; United Arab Emirates Readers are invited to submit letters for publication in this department. Submit them to: The Editor, Journal of Occupational and Environmental Medicine, 605 Worcester Road, Towson, MD 21286-7834. Letters should be sent as hard copy with an accompanying diskette and should be designated “For Publication.”

Cement Dust Exposure and Ventilatory Function Impairment: An Exposure–Response Study

We investigated cumulative total cement dust exposure and ventilatory function impairment at a Portland cement factory in Tanzania. All 126 production workers were exposed. The control group comprised all 88 maintenance workers and 32 randomly chosen office workers. Exposed workers had significantly lower forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow rate (PEF), FEV1/FVC, FVC%, FEV1% and PEF%, than controls adjusted for age, duration of employment, height, and pack-years. Cumulative total dust exposure was significantly associated with reduced FVC, forced expiratory volume in 1 second, and peak expiratory flow rate adjusted for age, height and pack-years. Cumulative total dust exposure more than 300 mg/m year versus lower than 100 mg/m years was significantly associated with increased risk of developing airflow limitation (odds ratio = 9.9). The current occupational exposure limit for total cement dust (10 mg/m) appears to be too high to prevent respiratory health effects among cement workers.

A subclinical impairment of ventilatory function in cervical spondylotic myelopathy

Nomura T, Tani T, Kitaoka K, Enoki H, Ishida K. A subclinical impairment of ventilatory function in cervical spondylotic myelopathy. Arch Phys Med Rehabil 2004;85:1210–1. Objective To evaluate the ventilatory function in patients with cervical spondylotic myelopathy (CSM). Design Prospective cohort study. Setting Medical school in Japan. Participants Thirty-seven consecutive patients with CSM. Interventions All the patients had surgical intervention for mild to moderate spastic limb paresis. Main outcome measures Analysis of the maximum voluntary ventilation (MVV) in addition to routine spirometry before and after surgical decompression. Functional assessment was made by using the Japanese Orthopaedic Association (JOA) Scale. Results The MVV (% predicted) increased significantly ( P<.002) from 77%±19% preoperatively to 84%±20% postoperatively. None of the other routine spirometric data (ie, vital capacity, forced vital capacity, forced expired volume in 1 second, peak expiratory flow rate) increased significantly. According to the JOA score, tetraparesis improved significantly ( P<.0001) from 8.3±3.2 preoperatively to 11.4±3.0 postoperatively. The ratio of postoperative to preoperative MVV showed a significant correlation ( r=.538, P<.002) with that of the JOA score. Conclusions MVV provides a useful measure for monitoring ventilatory impairment in patients with myelopathy.