Breathing is considered the common factor that links studying,sleeping,and activities.It is one of the primary indicators that is frequently considered when determining whether or not an unconscious individual is stil...Breathing is considered the common factor that links studying,sleeping,and activities.It is one of the primary indicators that is frequently considered when determining whether or not an unconscious individual is still alive.The evolution and development process of the respiratory system that occurs in a foetus is primarily from head to tail(cephalocaudal).Many changes occur throughout this period until the 28th week of pregnancy at which the foetus^respiratory system will attain adequate development for the rest of his or her life.The respiratory system comprises of the lungs and the encompassing thoracic wall,which includes the thoracic cages,midriff(diaphragm),and the abdominal wall.Spirometry is a procedure used for estimating air volumes that enter and exit the pulmonary system with the aid of a spirometer.The various pulmonary parameters that reflect pulmonary ventilation are of great significance in diagnosing respiratory diseases.The respiratory system will be discussed in more detail in this article.展开更多
AIM To compare high-resolution computed tomography(HRCT) findings between humoral primary immunodeficiencies(hPIDs) subtypes; to correlate these findings to pulmonary function tests(PFTs).METHODS We retrospectively id...AIM To compare high-resolution computed tomography(HRCT) findings between humoral primary immunodeficiencies(hPIDs) subtypes; to correlate these findings to pulmonary function tests(PFTs).METHODS We retrospectively identified 52 consecutive adult patients with hPIDs who underwent 64-row HRCT and PFTs at the time of diagnosis. On a per-patient basis, an experienced radiologist recorded airway abnormalities(bronchiectasis,airway wall thickening, mucus plugging, tree-in-bud, and air-trapping) and parenchymal-interstitial abnormalities(consolidations, ground-glass opacities,linear and/or irregular opacities, nodules, and bullae/cysts) found on HRCT.The chi-square test was performed to compare the prevalence of each abnormality among patients with different subtypes of hPIDs. Overall logistic regression analysis was performed to assess whether HRCT findings predicted obstructive and/or restrictive PFTs results(absent-to-mild vs moderate-tosevere).RESULTS Thirty-eight of the 52 patients with hPIDs showed common variable immunodeficiency disorders(CVID), while the remaining 14 had CVID-like conditions(i.e., 11 had isolated IgG subclass deficiencies and 3 had selective IgA deficiencies). The prevalence of most HRCT abnormalities was not significantly different between CVID and CVID-like patients(P > 0.05), except for linear and/or irregular opacities(prevalence of 31.6% in the CVID group and 0 in the CVID-like group; P = 0.0427). Airway wall thickening was the most frequent HRCT abnormality found in both CVID and CVID-like patients(71% of cases in both groups). The presence of tree-in-bud abnormalities was an independent predictor of moderate-to-severe obstructive defects at PFTs(Odds Ratio, OR, of 18.75, P < 0.05), while the presence of linear and/or irregular opacities was an independent predictor of restrictive defects at PFTs(OR = 13.00; P < 0.05).CONCLUSION CVID and CVID-like patients showed similar HRCT findings. Tree-in-bud and linear and/or irregular opacities predicted higher risks of, respectively,obstructive and restrictive defects at PFTs.展开更多
AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomocjraphy (HRCT) in patients with chronic hepatitis C virus (HCV) infection. METHODS:Thirty-four patients with...AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomocjraphy (HRCT) in patients with chronic hepatitis C virus (HCV) infection. METHODS:Thirty-four patients with chronic HCV infection without diagnosis of any pulmonary diseases and 10 healthy cases were enrolled in the study,PFT and HRCT were performed in all cases. RESULTS:A decrease lower than 80% of the predicted value was detected in vital capacity in 9/34 patients,in forced expiratory volume in one second in 8/34 patients,and in forced expiratory flow 25-75 in 15/34 patients,respectively.Carbon monoxide diffusing capacity (DLCO) was decreased in 26/34 patients.Findings of interstitial pulmonary involvement were detected in the HRCT of 16/34 patients.Significant difference was found between controls and patients with HCV infection in findings of HRCT (X^2=4.7,P=0.003).Knodell histological activity index (KHAI) of 28/34 patients in whom liver biopsy was applied was 9.0±4.7.HRCT findings,PFT values and DLCO were not affected by KHAI in patients with HCV infection.In these patients,all the parameters were related with age. CONCLUSION:We suggest that chronic hepatitis C virus infection may cause pulmonary interstitial involvement without evident respiratory symptoms.展开更多
Human adenoviruses(HAdVs)can cause acute hepatitis in immunocompromised patients.However,it is unclear whether HAdVs are contributors to hepatitis in immunocompetent children.In this study,the liver function test(LFT)...Human adenoviruses(HAdVs)can cause acute hepatitis in immunocompromised patients.However,it is unclear whether HAdVs are contributors to hepatitis in immunocompetent children.In this study,the liver function test(LFT)results were retrospectively analyzed among children hospitalized(age<14 years)between January 2016 and October 2019 for acute respiratory infection caused by adenoviruses.Alanine transaminase(ALT)and aspartate aminotransferase(AST)levels were elevated in 7.74%and 46.89%of patients,respectively.All patients with>2 folds of the upper limit of ALT or AST levels were infected with HAdV-7 or HAdV-55.Significantly higher levels of ALT,AST,γ-glutamyl transpeptidase(γ-GT),and lower albumin levels were observed in the HAdV-7 infection group than in the HAdV-3 infection group.HAdV-55 infection led to significantly higherγ-GT,total bilirubin,and direct bilirubin levels than the other infection types.The records of four patients with serial monitoring of the LFT results were further analyzed.Multiple indicators remained abnormal during the entire hospitalization in these patients.These results indicate that HAdV infection is often accompanied by abnormal liver function,and HAdV-7 and HAdV-55 might be under-recognized contributors to hepatitis among children.展开更多
AIM:To investigate the prevalence of chronic dyspnea and its relationship to respiratory muscle function in end-stage liver disease.METHODS:Sixty-eight consecutive,ambulatory,Caucasian patients with end-stage liver di...AIM:To investigate the prevalence of chronic dyspnea and its relationship to respiratory muscle function in end-stage liver disease.METHODS:Sixty-eight consecutive,ambulatory,Caucasian patients with end-stage liver disease,candidates for liver transplantation,were referred for preoperative respiratory function assessment.Forty of these(29 men) were included in this preliminary study after applying strict inclusion and exclusion criteria.Seventeen of 40 patients(42%) had ascites,but none of them was cachectic.Fifteen of 40 patients(38%)had a history of hepatic encephalopathy,though none of them was symptomatic at study time.All patients with a known history and/or presence of co-morbidities were excluded.Chronic dyspnea was rated according to the modified medical research council(mMRC) 6-point scale.Liver disease severity was assessed according to the Model for end-stage liver disease(MELD).Routine lung function tests,maximum static expiratory(Pemax) and inspiratory(Pimax) mouth pressures were measured.Respiratory muscle strength(RMS) was calculated from Pimax and Pemax values.In addition,arterial blood gases and pattern of breathing(VE:minute ventilation;VT:tidal volume;VT/TI:mean inspiratory flow;TI:duration of inspiration) were measured.RESULTS:Thirty-five(88%) of 40 patients aged(mean ± SD) 52 ± 10 years reported various degrees of chronic dyspnea(mMRC),ranging from 0 to 4,with a mean value of 2.0 ± 1.2.MELD score was 14 ± 6.Pemax,percent of predicted(%pred) was 105 ± 35,Pimax,%pred was 90 ± 29,and RMS,%pred was 97 ± 30.These pressures were below the normal limits in 12(30%),15(38%),and 14(35%) patients,respectively.Furthermore,comparing the subgroups of ascites to non-ascites patients,all respiratory muscle indices measured were found significantly decreased in ascites patients.Patients with ascites also had a significantly worse MELD score compared to non-ascites ones(P = 0.006).Significant correlations were found between chronic dyspnea and respiratory muscle function indices in all patients.Specifically,mMRC score was significantly correlated with Pemax,Pimax,and RMS(r =-0.53,P < 0.001;r =-0.42,P < 0.01;r =-0.51,P < 0.001,respectively).These correlations were substantially closer in the non-ascites subgroup(r =-0.82,P < 0.0001;r =-0.61,P < 0.01;r =-0.79,P < 0.0001,respectively) compared to all patients.Similar results were found for the relationship between mMRC vs MELD score,and MELD score vs respiratory muscle strength indices.In all patients the sole predictor of mMRC score was RMS(r =-0.51,P < 0.001).In the subgroup of patients without ascites this relationship becomes closer(r =-0.79,P < 0.001),whilst this relationship breaks down in the subgroup of patients with ascites.The disappearance of such a correlation may be due to the fact that ascites acts as a "confounding" factor.PaCO2(4.4 ± 0.5 kPa) was increased,whereas pH(7.49 ± 0.04) was decreased in 26(65%) and 34(85%) patients,respectively.PaO2(12.3 ± 0.04 kPa) was within normal limits.VE(11.5 ± 3.5 L/min),VT(0.735 ± 0.287 L),and VT/TI(0.449±0.129 L/s) were increased signifying hyperventilation in both subgroups of patients.VT/TI was significantly higher in patients with ascites than without ascites.Significant correlations,albeit weak,were found for PaCO2 with VE and VT/TI(r =-0.44,P < 0.01;r =-0.41,P < 0.01,respectively).CONCLUSION:The prevalence of chronic dyspnea is 88% in end-stage liver disease.The mMRC score closely correlates with respiratory muscle strength.展开更多
In six healthy male subjects, the changes of respiratory airflow rate and heart rate were de-termined in sensory units of five just noticeable difference （JND） steps caused by inspiratory resistive （IR） loads rang...In six healthy male subjects, the changes of respiratory airflow rate and heart rate were de-termined in sensory units of five just noticeable difference （JND） steps caused by inspiratory resistive （IR） loads ranging 0.28-1. 62 kPa.L<sup>-1</sup> s and physical stimuli in IR corresponding to JND steps andcombined resistance （CR） of different ratios equivalent to 2, 4 JND sensation at rest and duringmild and moderate muscular exercises (250 and 500 kgm·min<sup>-1</sup>) performed on a bicycle ergometer.The results suggest that the tendency of effects on respiratory pattern, within the test range of IRloads, are approximately consistent at rest and during mild and moderate exercise, that when theCR load is carried, the changes of respiratory pattern at rest and during mild exercise are similar,but more apparently during moderate exercise, and that the heart rote only increases with the rise ofexertion intensity, without apparent influence of resistive loads.展开更多
BACKGROUND Patients with stroke frequently experience pulmonary dysfunction.AIM To explore the effects of information-motivation-behavioral(IMB)skills modelbased nursing care on pulmonary function,blood gas indices,co...BACKGROUND Patients with stroke frequently experience pulmonary dysfunction.AIM To explore the effects of information-motivation-behavioral(IMB)skills modelbased nursing care on pulmonary function,blood gas indices,complication rates,and quality of life(QoL)in stroke patients with pulmonary dysfunction.METHODS We conducted a controlled study involving 120 stroke patients with pulmonary dysfunction.The control group received routine care,whereas the intervention group received IMB-model-based nursing care.Various parameters including pulmonary function,blood gas indices,complication rates,and QoL were assessed before and after the intervention.RESULTS Baseline data of the control and intervention groups were comparable.Post-intervention,the IMB model-based care group showed significant improvements in pulmonary function indicators,forced expiratory volume in 1 sec,forced vital capacity,and peak expiratory flow compared with the control group.Blood gas indices,such as arterial oxygen pressure and arterial oxygen saturation,increased significantly,and arterial carbon dioxide partial.pressure decreased significantly in the IMB model-based care group compared with the control group.The intervention group also had a lower complication rate(6.67%vs 23.33%)and higher QoL scores across all domains than the control group.CONCLUSION IMB model-based nursing care significantly enhanced pulmonary function,improved blood gas indices,reduced complication rates,and improved the QoL of stroke patients with pulmonary dysfunction.Further research is needed to validate these results and to assess the long-term efficacy and broader applicability of the model.展开更多
Despite wide application of hydrated calcium sulfate, possible respiratory effects of long-term occupational exposure to high concentrations of this chemical have only been investigated in a limited number of epidemio...Despite wide application of hydrated calcium sulfate, possible respiratory effects of long-term occupational exposure to high concentrations of this chemical have only been investigated in a limited number of epidemiological studies. This study is undertaken to examine this issue, more thoroughly. This cross-sectional study is carried out at a local gypsum plant in Shiraz, capital of Fars province situated in south western Iran. All exposed subjects (20 male workers) and 20 healthy non-exposed male individuals as the referent group are investigated. Prevalence of respiratory symptoms among the studied subjects is evaluated and they undergo spirometry test (twice for the exposed group and once for the unexposed employees). Moreover, to assess the extent to which workers are exposed to gypsum dust and using standard methods, inhalable and respirable fractions of this compound are measured in different dusty worksites. Average airborne concentration of inhalable dust fraction is estimated to be 24 ± 14.76 mg/m3 which is higher than the recommended threshold limit value (TLV) for this chemical. Respiratory symptoms such as phlegm, wheezing and dyspnea are significantly more prevalent in exposed subjects than in non-exposed employees (p < 0.05). The results of ventilatory function tests (pre- shift) don’t show any significant differences between both groups. However, some post-shift parameters of ventilatory function such as FVC, FEV1 and FEV1/FVC ratio are significantly lower than those of preshift and referent group. Exposure to high atmospheric concentrations of gypsum dust is associated with a significant increase in the prevalence of respiratory symptoms along with acute reversible significant decreases in some parameters of ventilatory function.展开更多
文摘Breathing is considered the common factor that links studying,sleeping,and activities.It is one of the primary indicators that is frequently considered when determining whether or not an unconscious individual is still alive.The evolution and development process of the respiratory system that occurs in a foetus is primarily from head to tail(cephalocaudal).Many changes occur throughout this period until the 28th week of pregnancy at which the foetus^respiratory system will attain adequate development for the rest of his or her life.The respiratory system comprises of the lungs and the encompassing thoracic wall,which includes the thoracic cages,midriff(diaphragm),and the abdominal wall.Spirometry is a procedure used for estimating air volumes that enter and exit the pulmonary system with the aid of a spirometer.The various pulmonary parameters that reflect pulmonary ventilation are of great significance in diagnosing respiratory diseases.The respiratory system will be discussed in more detail in this article.
基金funded by Department of Medicine, University of Udine (Udine, Italy) in accordance with Good Publication Practice (GPP3) guidelines (http://www.ismpp.org/gpp3)
文摘AIM To compare high-resolution computed tomography(HRCT) findings between humoral primary immunodeficiencies(hPIDs) subtypes; to correlate these findings to pulmonary function tests(PFTs).METHODS We retrospectively identified 52 consecutive adult patients with hPIDs who underwent 64-row HRCT and PFTs at the time of diagnosis. On a per-patient basis, an experienced radiologist recorded airway abnormalities(bronchiectasis,airway wall thickening, mucus plugging, tree-in-bud, and air-trapping) and parenchymal-interstitial abnormalities(consolidations, ground-glass opacities,linear and/or irregular opacities, nodules, and bullae/cysts) found on HRCT.The chi-square test was performed to compare the prevalence of each abnormality among patients with different subtypes of hPIDs. Overall logistic regression analysis was performed to assess whether HRCT findings predicted obstructive and/or restrictive PFTs results(absent-to-mild vs moderate-tosevere).RESULTS Thirty-eight of the 52 patients with hPIDs showed common variable immunodeficiency disorders(CVID), while the remaining 14 had CVID-like conditions(i.e., 11 had isolated IgG subclass deficiencies and 3 had selective IgA deficiencies). The prevalence of most HRCT abnormalities was not significantly different between CVID and CVID-like patients(P > 0.05), except for linear and/or irregular opacities(prevalence of 31.6% in the CVID group and 0 in the CVID-like group; P = 0.0427). Airway wall thickening was the most frequent HRCT abnormality found in both CVID and CVID-like patients(71% of cases in both groups). The presence of tree-in-bud abnormalities was an independent predictor of moderate-to-severe obstructive defects at PFTs(Odds Ratio, OR, of 18.75, P < 0.05), while the presence of linear and/or irregular opacities was an independent predictor of restrictive defects at PFTs(OR = 13.00; P < 0.05).CONCLUSION CVID and CVID-like patients showed similar HRCT findings. Tree-in-bud and linear and/or irregular opacities predicted higher risks of, respectively,obstructive and restrictive defects at PFTs.
文摘AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomocjraphy (HRCT) in patients with chronic hepatitis C virus (HCV) infection. METHODS:Thirty-four patients with chronic HCV infection without diagnosis of any pulmonary diseases and 10 healthy cases were enrolled in the study,PFT and HRCT were performed in all cases. RESULTS:A decrease lower than 80% of the predicted value was detected in vital capacity in 9/34 patients,in forced expiratory volume in one second in 8/34 patients,and in forced expiratory flow 25-75 in 15/34 patients,respectively.Carbon monoxide diffusing capacity (DLCO) was decreased in 26/34 patients.Findings of interstitial pulmonary involvement were detected in the HRCT of 16/34 patients.Significant difference was found between controls and patients with HCV infection in findings of HRCT (X^2=4.7,P=0.003).Knodell histological activity index (KHAI) of 28/34 patients in whom liver biopsy was applied was 9.0±4.7.HRCT findings,PFT values and DLCO were not affected by KHAI in patients with HCV infection.In these patients,all the parameters were related with age. CONCLUSION:We suggest that chronic hepatitis C virus infection may cause pulmonary interstitial involvement without evident respiratory symptoms.
基金This study was supported by the National Natural Science Foundation of China(82072264,81970003)Natural Science Foundation of Guangdong Province,China(2021A1515011071)The study sponsors had no involvement in the study design,in the collection,analysis and interpretation of data,in the writing of the manuscript,and in the decision to submit the manuscript for publication.
文摘Human adenoviruses(HAdVs)can cause acute hepatitis in immunocompromised patients.However,it is unclear whether HAdVs are contributors to hepatitis in immunocompetent children.In this study,the liver function test(LFT)results were retrospectively analyzed among children hospitalized(age<14 years)between January 2016 and October 2019 for acute respiratory infection caused by adenoviruses.Alanine transaminase(ALT)and aspartate aminotransferase(AST)levels were elevated in 7.74%and 46.89%of patients,respectively.All patients with>2 folds of the upper limit of ALT or AST levels were infected with HAdV-7 or HAdV-55.Significantly higher levels of ALT,AST,γ-glutamyl transpeptidase(γ-GT),and lower albumin levels were observed in the HAdV-7 infection group than in the HAdV-3 infection group.HAdV-55 infection led to significantly higherγ-GT,total bilirubin,and direct bilirubin levels than the other infection types.The records of four patients with serial monitoring of the LFT results were further analyzed.Multiple indicators remained abnormal during the entire hospitalization in these patients.These results indicate that HAdV infection is often accompanied by abnormal liver function,and HAdV-7 and HAdV-55 might be under-recognized contributors to hepatitis among children.
文摘AIM:To investigate the prevalence of chronic dyspnea and its relationship to respiratory muscle function in end-stage liver disease.METHODS:Sixty-eight consecutive,ambulatory,Caucasian patients with end-stage liver disease,candidates for liver transplantation,were referred for preoperative respiratory function assessment.Forty of these(29 men) were included in this preliminary study after applying strict inclusion and exclusion criteria.Seventeen of 40 patients(42%) had ascites,but none of them was cachectic.Fifteen of 40 patients(38%)had a history of hepatic encephalopathy,though none of them was symptomatic at study time.All patients with a known history and/or presence of co-morbidities were excluded.Chronic dyspnea was rated according to the modified medical research council(mMRC) 6-point scale.Liver disease severity was assessed according to the Model for end-stage liver disease(MELD).Routine lung function tests,maximum static expiratory(Pemax) and inspiratory(Pimax) mouth pressures were measured.Respiratory muscle strength(RMS) was calculated from Pimax and Pemax values.In addition,arterial blood gases and pattern of breathing(VE:minute ventilation;VT:tidal volume;VT/TI:mean inspiratory flow;TI:duration of inspiration) were measured.RESULTS:Thirty-five(88%) of 40 patients aged(mean ± SD) 52 ± 10 years reported various degrees of chronic dyspnea(mMRC),ranging from 0 to 4,with a mean value of 2.0 ± 1.2.MELD score was 14 ± 6.Pemax,percent of predicted(%pred) was 105 ± 35,Pimax,%pred was 90 ± 29,and RMS,%pred was 97 ± 30.These pressures were below the normal limits in 12(30%),15(38%),and 14(35%) patients,respectively.Furthermore,comparing the subgroups of ascites to non-ascites patients,all respiratory muscle indices measured were found significantly decreased in ascites patients.Patients with ascites also had a significantly worse MELD score compared to non-ascites ones(P = 0.006).Significant correlations were found between chronic dyspnea and respiratory muscle function indices in all patients.Specifically,mMRC score was significantly correlated with Pemax,Pimax,and RMS(r =-0.53,P < 0.001;r =-0.42,P < 0.01;r =-0.51,P < 0.001,respectively).These correlations were substantially closer in the non-ascites subgroup(r =-0.82,P < 0.0001;r =-0.61,P < 0.01;r =-0.79,P < 0.0001,respectively) compared to all patients.Similar results were found for the relationship between mMRC vs MELD score,and MELD score vs respiratory muscle strength indices.In all patients the sole predictor of mMRC score was RMS(r =-0.51,P < 0.001).In the subgroup of patients without ascites this relationship becomes closer(r =-0.79,P < 0.001),whilst this relationship breaks down in the subgroup of patients with ascites.The disappearance of such a correlation may be due to the fact that ascites acts as a "confounding" factor.PaCO2(4.4 ± 0.5 kPa) was increased,whereas pH(7.49 ± 0.04) was decreased in 26(65%) and 34(85%) patients,respectively.PaO2(12.3 ± 0.04 kPa) was within normal limits.VE(11.5 ± 3.5 L/min),VT(0.735 ± 0.287 L),and VT/TI(0.449±0.129 L/s) were increased signifying hyperventilation in both subgroups of patients.VT/TI was significantly higher in patients with ascites than without ascites.Significant correlations,albeit weak,were found for PaCO2 with VE and VT/TI(r =-0.44,P < 0.01;r =-0.41,P < 0.01,respectively).CONCLUSION:The prevalence of chronic dyspnea is 88% in end-stage liver disease.The mMRC score closely correlates with respiratory muscle strength.
文摘In six healthy male subjects, the changes of respiratory airflow rate and heart rate were de-termined in sensory units of five just noticeable difference （JND） steps caused by inspiratory resistive （IR） loads ranging 0.28-1. 62 kPa.L<sup>-1</sup> s and physical stimuli in IR corresponding to JND steps andcombined resistance （CR） of different ratios equivalent to 2, 4 JND sensation at rest and duringmild and moderate muscular exercises (250 and 500 kgm·min<sup>-1</sup>) performed on a bicycle ergometer.The results suggest that the tendency of effects on respiratory pattern, within the test range of IRloads, are approximately consistent at rest and during mild and moderate exercise, that when theCR load is carried, the changes of respiratory pattern at rest and during mild exercise are similar,but more apparently during moderate exercise, and that the heart rote only increases with the rise ofexertion intensity, without apparent influence of resistive loads.
文摘BACKGROUND Patients with stroke frequently experience pulmonary dysfunction.AIM To explore the effects of information-motivation-behavioral(IMB)skills modelbased nursing care on pulmonary function,blood gas indices,complication rates,and quality of life(QoL)in stroke patients with pulmonary dysfunction.METHODS We conducted a controlled study involving 120 stroke patients with pulmonary dysfunction.The control group received routine care,whereas the intervention group received IMB-model-based nursing care.Various parameters including pulmonary function,blood gas indices,complication rates,and QoL were assessed before and after the intervention.RESULTS Baseline data of the control and intervention groups were comparable.Post-intervention,the IMB model-based care group showed significant improvements in pulmonary function indicators,forced expiratory volume in 1 sec,forced vital capacity,and peak expiratory flow compared with the control group.Blood gas indices,such as arterial oxygen pressure and arterial oxygen saturation,increased significantly,and arterial carbon dioxide partial.pressure decreased significantly in the IMB model-based care group compared with the control group.The intervention group also had a lower complication rate(6.67%vs 23.33%)and higher QoL scores across all domains than the control group.CONCLUSION IMB model-based nursing care significantly enhanced pulmonary function,improved blood gas indices,reduced complication rates,and improved the QoL of stroke patients with pulmonary dysfunction.Further research is needed to validate these results and to assess the long-term efficacy and broader applicability of the model.
文摘Despite wide application of hydrated calcium sulfate, possible respiratory effects of long-term occupational exposure to high concentrations of this chemical have only been investigated in a limited number of epidemiological studies. This study is undertaken to examine this issue, more thoroughly. This cross-sectional study is carried out at a local gypsum plant in Shiraz, capital of Fars province situated in south western Iran. All exposed subjects (20 male workers) and 20 healthy non-exposed male individuals as the referent group are investigated. Prevalence of respiratory symptoms among the studied subjects is evaluated and they undergo spirometry test (twice for the exposed group and once for the unexposed employees). Moreover, to assess the extent to which workers are exposed to gypsum dust and using standard methods, inhalable and respirable fractions of this compound are measured in different dusty worksites. Average airborne concentration of inhalable dust fraction is estimated to be 24 ± 14.76 mg/m3 which is higher than the recommended threshold limit value (TLV) for this chemical. Respiratory symptoms such as phlegm, wheezing and dyspnea are significantly more prevalent in exposed subjects than in non-exposed employees (p < 0.05). The results of ventilatory function tests (pre- shift) don’t show any significant differences between both groups. However, some post-shift parameters of ventilatory function such as FVC, FEV1 and FEV1/FVC ratio are significantly lower than those of preshift and referent group. Exposure to high atmospheric concentrations of gypsum dust is associated with a significant increase in the prevalence of respiratory symptoms along with acute reversible significant decreases in some parameters of ventilatory function.
