Impaired Pulmonary Function Tests Research Articles

Patients With Post-COVID-19 Respiratory Condition: Chest Computed Tomography Findings and Pulmonary Function Tests and Comparison With Asymptomatic Participants.

The aims of this study were to assess the chest computed tomography (CT) findings in post-COVID-19 respiratory condition (rPCC) patients and compare the findings with asymptomatic participants (APs). It also aimed to evaluate the relationship between CT findings and pulmonary function tests (PFTs) in rPCC patients. Finally, it aimed to compare the quantitative chest CT findings and PFT results of patients with rPCC and APs. We retrospectively enrolled consecutive patients with rPCC who underwent unenhanced chest CT and PFTs between June 2020 and September 2022. In addition, a control group (APs) was prospectively formed and underwent nonenhanced chest CT and PFTs. The presence and extent of abnormalities in unenhanced chest CT images were evaluated qualitatively and semiquantitatively in a blinded manner. We used fully automatic software for automatic lung and airway segmentation and quantitative analyses. Sixty-three patients with rPCC and 23 APs were investigated. Reticulation/interstitial thickening and extent of parenchymal abnormalities on CT were significantly greater in the rPCC group than in the control group ( P = 0.001 and P = 0.004, respectively). Computed tomography extent score was significantly related to length of hospital stay, age, and intensive care unit stay (all P s ≤ 0.006). The rPCC group also had a lower 85th percentile attenuation lung volume ( P = 0.037). The extent of parenchymal abnormalities was significantly correlated with carbon monoxide diffusing capacity ( r = -0.406, P = 0.001), forced vital capacity (FVC) ( r = -0.342, P = 0.002), and forced expiratory volume in 1 second/FVC ( r = 0.427, P < 0.001) values. Pulmonary function tests revealed significantly lower carbon monoxide diffusing capacity ( P < 0.001), FVC ( P = 0.036), and total lung capacity ( P < 0.001) values in the rPCC group. The rPCC is characterized by impaired PFTs, a greater extent of lung abnormalities on CT, and decreased 85th percentile attenuation lung volume. Advanced age, intensive care unit admission history, and extended hospital stay are risk factors for chest CT abnormalities.

Hyperpolarized Xenon-129: A New Tool to Assess Pulmonary Physiology in Patients with Pulmonary Fibrosis.

The existing tools to quantify lung function in interstitial lung diseases have significant limitations. Lung MRI imaging using inhaled hyperpolarized xenon-129 gas (129Xe) as a contrast agent is a new technology for measuring regional lung physiology. We sought to assess the utility of the 129Xe MRI in detecting impaired lung physiology in usual interstitial pneumonia (UIP). After institutional review board approval and informed consent and in compliance with HIPAA regulations, we performed chest CT, pulmonary function tests (PFTs), and 129Xe MRI in 10 UIP subjects and 10 healthy controls. The 129Xe MRI detected highly heterogeneous abnormalities within individual UIP subjects as compared to controls. Subjects with UIP had markedly impaired ventilation (ventilation defect fraction: UIP: 30 ± 9%; healthy: 21 ± 9%; p = 0.026), a greater amount of 129Xe dissolved in the lung interstitium (tissue-to-gas ratio: UIP: 1.45 ± 0.35%; healthy: 1.10 ± 0.17%; p = 0.014), and impaired 129Xe diffusion into the blood (RBC-to-tissue ratio: UIP: 0.20 ± 0.06; healthy: 0.28 ± 0.05; p = 0.004). Most MRI variables had no correlation with the CT and PFT measurements. The elevated level of 129Xe dissolved in the lung interstitium, in particular, was detectable even in subjects with normal or mildly impaired PFTs, suggesting that this measurement may represent a new method for detecting early fibrosis. The hyperpolarized 129Xe MRI was highly sensitive to regional functional changes in subjects with UIP and may represent a new tool for understanding the pathophysiology, monitoring the progression, and assessing the effectiveness of treatment in UIP.

Impact of mannose-binding lectin gene polymorphism on lung functions among workers exposed to airborne Aspergillus in a wastewater treatment plant in Egypt

In this study, the risk of Aspergillus (Asp.) positivity and its respiratory health impacts on wastewater treatment plant (WWTP) workers were studied. In addition, it identified the geno-susceptibility role of mannose-binding lectin 2 (MBL2) gene polymorphisms and the mannose-binding lectin (MBL) serum levels on the pulmonary functions of the Asp.-positive workers. Pulmonary function tests (PFTs) were performed for 89 workers from a selected WWTP, after exclusion of the smokers. Molecular identification of Asp. blood positivity was done by 18S rRNA sequencing. Determination of MBL2 gene polymorphism and estimation of MBL serum levels were done. PFTs revealed abnormalities in 49.2% of the workers. Asp. was positive in 42.5% of the workers with different species. Among the Asp.-positive workers, 6.5% of the workers were with obstructive PFTs, 12.9% with restriction, and 22.6% with combined PFT abnormalities. MBL2 genotyping showed that wild genotype AA was common (68.5%) among Asp.-positive workers compared to the other genotypes. This allele, whether homozygous or heterozygous, was significantly associated with decline in PFTs of the exposed workers. MBL serum levels were significantly lower in workers with obstructive, restrictive, and combined PFT abnormalities compared to those with normal PFTs, and in the workers with Asp.-positive species than the Asp.-negative workers. Moreover, it was significantly lower in workers with Asp. fumigatus compared to that in the workers with other Asp. species, and in the Asp.-positive workers with homozygous or heterozygous A allele compared to that in the Asp.-positive workers with homozygous B allele. Working in a WWTP can be associated with impaired PFTs due to exposure to airborne fungi. MBL2 genotyping showed that Asp.-positive workers with homozygous or heterozygous A allele were at risk to develop decline in their PFTs.

Clinical and serological characteristics of systemic sclerosis: Experience of a tertiary care center in Pakistan.

Objectives This study aims to evaluate the clinical and serological characteristics of systemic sclerosis (SSc) in Pakistani population.Patients and methods This prospective, cross-sectional study included a total of 38 patients (6 males, 32 females; mean age: 34.5±1.5 years; range, 16 to 60 years) with SSc who were admitted to our rheumatology clinic between November 2019 and January 2020. We evaluated the clinical, serological, and radiological features of SSc patients.Results Thirty-four (89.5%) patients developed Raynaud phenomenon at the time of disease onset, while sclerodactyly was found in 34 (89.5%), digital ulcers in 25 (65.8%), and tendon friction rub in 12 (31.6%) patients. Interstitial lung disease was present in 30 (78.9%) patients with a higher prevalence in diffuse scleroderma (100%) than in limited scleroderma (70%) (p=0.01). Pulmonary hypertension was present in 18 patients with a significantly higher prevalence in diffuse disease (57.1%) than limited disease (11.8%) (p<0.01). Thirty (78.9%) patients had impaired pulmonary function tests. Fibromyalgia was present in seven (18.4%) patients, and depression was present in 10 (26.3%) patients. Antinuclear antibody (ANA) was positive in 30 (78.9%) patients. Anti-Scl-70 antibodies were present in 24 (63.2%) patients with a significant association with diffuse disease (85% vs. 35.3%, respectively; p<0.01). The anti-centromere antibodies (ACA) were present in 20 (52.6%) patients with a significantly higher rate in limited disease (94.2% vs. 19.0%, respectively; p<0.01).Conclusion Scleroderma has a female preponderance. Raynaud phenomenon is the most initial clinical feature followed by other manifestations of a variable course and disease severity.

Late Morbidity among Survivors of Childhood Cancers; Experience at Tertiary Care Cancer Hospital.

Long-term survivors of childhood malignancies are at increased risk of experiencing treatment-related morbidities. Survival into late adulthood in these children provides ample time for the acquisition of long-term sequelae. This study aimed to determine the late adverse effects among long-term survivors of childhood cancer from a low-income country perspective. Data were retrospectively collected from review of charts of patients aged under 18 years at the time of their primary diagnosis between 1 January, 1995, and 31 December, 2008, and who survived for at least 5 years after completion of their treatment. Analysed data included demographics, cancer type, treatment modality, types of chemotherapy agents administered and specific late morbidities including frequency of azoospermia, oligospermia, endocrine abnormalities, hearing and pulmonary function impairment and cardiac dysfunction among the long-term survivors of cancer. The total number of patients was 300 with a mean age of 18 ± 2 years. The male to female ratio was 2.7:1. Median follow-up duration was 18 years (range: 5-25 years). Seventy-seven percent of patients were from Punjab, 20% were from Khyber Pakhtunkhwa and 3% were from other provinces. Fifty percent had a diagnosis of Hodgkin lymphoma, 17% had acute lymphoblastic leukaemia, 13% had non-Hodgkin lymphoma, 10% had germ cell tumours and 10% had other tumours. Fifty-seven percent received chemotherapy, 23% had chemotherapy and radiotherapy, 15% had chemotherapy and surgery, 3% had chemotherapy, surgery and radiotherapy and 2% had only surgery. Notable long-term documented sequelae were; azoospermia/oligospermia in 64%, endocrine abnormalities in 25% with hypothyroidism in 13.5% and follicle-stimulating hormone and luteinizing hormone abnormalities in 11.5%, ototoxicity in 6.5%, impaired pulmonary function tests in 4.6%, cardiotoxicity in 2.4% and second malignancies (acute myeloid leukaemia and myelodysplastic syndrome) in 1%. Childhood cancer survivors are at increased risk of adverse treatment-related sequelae and a long-term follow-up plan should be in place in centres where they receive treatment for their primary disease.

Deep Learning Enables Automatic Classification of Emphysema Pattern at CT.

BackgroundPattern of emphysema at chest CT, scored visually by using the Fleischner Society system, is associated with physiologic impairment and mortality risk.PurposeTo determine whether participant-level emphysema pattern could predict impairment and mortality when classified by using a deep learning method.Materials and MethodsThis retrospective analysis of Genetic Epidemiology of COPD (COPDGene) study participants enrolled between 2007 and 2011 included those with baseline CT, visual emphysema scores, and survival data through 2018. Participants were partitioned into nonoverlapping sets of 2407 for algorithm training, 100 for validation and parameter tuning, and 7143 for testing. A deep learning algorithm using convolutional neural network and long short-term memory architectures was trained to classify pattern of emphysema according to Fleischner criteria. Deep learning scores were compared with visual scores and clinical parameters including pulmonary function tests. Cox proportional hazard models were used to evaluate relationships between emphysema scores and survival. The algorithm was also tested by using CT and clinical data in 1962 participants enrolled in the Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE) study.ResultsA total of 7143 COPDGene participants (mean age ± standard deviation, 59.8 years ± 8.9; 3734 men and 3409 women) were evaluated. Deep learning emphysema classifications were associated with impaired pulmonary function tests, 6-minute walk distance, and St George's Respiratory Questionnaire at univariate analysis (P < .001 for each). Testing in the ECLIPSE cohort showed similar associations (P < .001). In the COPDGene test cohort, deep learning emphysema classification improved the fit of linear mixed models in the prediction of these clinical parameters compared with visual scoring (P < .001). Compared with participants without emphysema, mortality was greater in participants classified by the deep learning algorithm as having any grade of emphysema (adjusted hazard ratios were 1.5, 1.7, 2.9, 5.3, and 9.7, respectively, for trace, mild, moderate, confluent, and advanced destructive emphysema; P < .05).ConclusionDeep learning automation of the Fleischner grade of emphysema at chest CT is associated with clinical measures of pulmonary insufficiency and the risk of mortality.© RSNA, 2019Online supplemental material is available for this article.

Tracking changes in nailfold capillaries during dermatomyositis treatment

To the Editor: The clinical features of dermatomyositis are believed to be due in part to small vessel vasculopathy and perivascular inflammation, which leads to a reduction in capillary density with compensatory dilatation of the remaining capillaries. 1 Dalakas M.C. Inflammatory muscle diseases. N Engl J Med. 2015; 373: 393-394 Crossref PubMed Scopus (2) Google Scholar In the skin, a manifestation of this is easily measurable is changes in capillary nailfolds. Indeed, a retrospective study of 92 juvenile dermatomyositis patients showed that nailfold capillary density is a marker of not just skin damage but also muscle damage and, therefore, appears to reflect the degree of systemic blood vessel alterations. 2 Schmeling H. Stephens S. Goia C. et al. Nailfold capillary density is importantly associated over time with muscle and skin disease activity in juvenile dermatomyositis. Rheumatology (Oxford). 2011; 50: 885-893 Crossref PubMed Scopus (52) Google Scholar Another study of 60 patients with juvenile dermatomyositis showed that low nailfold capillary density is associated with impaired pulmonary function tests. 3 Barth Z. Schwartz T. Flatø B. et al. The association between nailfold capillary density and pulmonary and cardiac involvement in medium- to long-standing juvenile dermatomyositis. Arthritis Care Res (Hoboken). 2018; ([Epub ahead of print]) PubMed Google Scholar The question remains if these changes in adult dermatomyositis are permanent and represent a persistent measure of overall disease-induced damage, or if on therapy, they are reversible, suggesting they are more a measure of disease activity. Our objective was to assess if these capillary changes reverse with the use of immunosuppressant therapy and if the rate or extent of reversal varies between therapeutic options.

Phrenic nerve decompression for the management of unilateral diaphragmatic paralysis - preoperative evaluation and operative technique.

Background:Unilateral diaphragmatic paralysis (UDP) can be a very disabling, typically causing shortness of breath and reduced exercise tolerance. We present a case of a surgical decompression of the phrenic nerve of a patient who presented with UDP, which occurred following cervical spine surgery.Methods:The workup for the etiology of UDP demonstrated paradoxical movement on “sniff test” and notably impaired pulmonary function tests. Seven months following the onset of the UDP, he underwent a surgical decompression of the phrenic nerve at the level of the anterior scalene.Results:He noted rapid symptomatic improvement following surgery and reversal of the above noted objective findings was documented. At his 4-year follow-up, he had complete resolution of his clinical symptoms. Repeated physiologic testing of his respiratory function had shown a complete reversal of his UDP.Conclusions:Anatomical compression of the phrenic nerve by redundant neck vasculature should be considered in the differential diagnosis of UDP. Here we demonstrated the techniques in workup and surgical management, with both subjective and objective evidence of success.

Spectrum of viral infections in post-transplant lung

Purpose: Infections remains a significant cause of morbidity and mortality among lung transplant recipients and initially may present with equivocal clinical findings and non-specific impaired pulmonary function tests. High-resolution computed tomography (HRCT) scan is a sensitive test for early detection of infective lung process.

Pulmonary function tests in type 1 diabetes adolescents with diabetic cardiovascular autonomic neuropathy

Chronic diabetic complications may afflict all organ tissues including cardiovascular and respiratory system. The aim of the study was to establish if the presence of cardiovascular autonomic neuropathy (CAN) was associated with impaired pulmonary function tests in adolescents with type 1 diabetes (T1D).46 adolescents with T1D and 25 healthy subjects at the age 15–19years were enrolled to the study. Basic anthropometric data, diabetes onset and duration, plasma glucose and A1c were established. Pulmonary function tests were measured by spirometry and the presence of CAN was examined by heart rate variability.Adolescents with T1D had significantly lower pulmonary function test parameters — FVC (p<0.01), FEV1 (p<0.01), MMEF (p<0.05) and PEFR (p<0.05) compared to the control subjects. In diabetic group, patients with CAN (CAN+, n=19) had significantly lower FVC (p<0.05), FEV1 (p<0.05) and PEFR (p<0.05) compared to patients without CAN (CAN−, n=27). All spirometric parameters were significantly lower in CAN+ subjects compared to healthy controls; however, no significant difference was found in these parameters between CAN− subjects and healthy controls. Spirometric parameters (FVC, FEV1) significantly positively correlated with diabetes onset and body mass index; and negatively correlated with diabetes duration and resting heart rate.Our results indicate that CAN may be associated with reduced pulmonary functions in adolescents with T1D.

Pulmonary hypertension associates with malnutrition and body composition hemodialysis patients

Background/Aim: The prevalence of pulmonary hypertension (PH) is reported between 17 and 56% in hemodialysis (HD) patients. Pathogenesis of PH in HD patients is still unclear. Malnutrition associating impaired pulmonary function tests in HD patients previously reported. Present study aimed to investigate an association between PH and nutrition and inflammation HD patients. Patients/Methods: Total 179 HD patients (109 M, 70 F) were included. Pulmonary artery pressure (PAP) and ejection fraction (EF) percentage was determined by echocardiography after a midweek HD session. Bioimpedance analyses were performed after dialysis. Percent body fat mass truncal fat (%), total body water (%), body-mass index was determined. Serum 25-OH vitamin D, albumin, lipid parameters, C-reactive protein (CRP), calcium, phosphorus, parathyroid hormone, ferritin levels, and hemogram were studied. Results: Pulmonary hypertension (PAP >35 mmHg) was found in 48 (26.8%) of 179 patients studied. Body-mass index (BMI) was negatively correlated with PAP (r = −0.34; p = 0.02). HD vintage, prevalence of diabetes, sex, type of vascular access were not different between patients with PH and without PH. Patients with PH were older (68.1 ± 14.4; 61.3 ± 14.7; p = 0.005). Percent body fat (19.8 ± 8.1% vs. 28.1 ± 10%; p = 0.001), albumin (3.4 ± 0.5 g/dl vs. 3.9 ± 3.3 g/dl; p = 0.0001), truncal fat (16.8 ± 10.7 vs. 26.4 ± 10.5; p = 0.001), triglyceride (147.9 ± 88.5 vs. 182.1 ± 97.7 mg/dl; p = 0.03), and total cholesterol (146.9 ± 34.5 vs. 169.5 ± 43 mg/dl; p = 0.004) levels were significantly lower in patients with PH than with no PH. Logistic regression analysis revealed that increased percent body fat, albumin, and total cholesterol associate with a decreased risk of PH. Conclusion: Present study demonstrated a significant association between malnutrition and PH in HD patients. Those results should be confirmed by further prospective studies including cytokine levels and spirometric measurements.

S135 A retrospective multi-centre study of the effects of allogeneic haematopoietic stem cell transplantation on pulmonary function

IntroductionAllogeneic haematopoietic stem cell transplantation (HSCT) is often complicated by serious pulmonary complications including severe infections, drug toxicity and graft vs host disease. However, there is limited data on the...

Lung involvement in patients with primary Sjögren’s syndrome: what are the predictors?

The aim of this study was to investigate the prevalence, predictors and radiological findings of primary Sjögren's syndrome (pSS)-associated lung involvement. This retrospective cohort study included 123 patients with demographic, clinical, laboratory and radiological data who were diagnosed with pSS. Lung involvement was defined based on the presence of pulmonary signs/symptoms and/or impaired pulmonary function tests along with alterations in high-resolution computerized tomography (HRCT). Thirty patients (24.4%) had pulmonary signs/symptoms at the initial presentation and/or during the follow-up period. Based on the criteria, 14 patients (11.4%) were defined as having pSS with lung involvement. The smoking rate, male/female ratio and the mean ages were found to be higher in patients with lung involvement (P < 0.05). Positive IgM-rheumatoid factor (RF), anti-La and anti-Ro results, the presence of hypergammaglobulinemia and lymphopenia had high specificity despite the low sensitivity rates to detect pSS-associated lung disease. A significant difference was found in forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV(1)) results between the patients with and without lung involvement. Impaired FEV(1) had high specificity and positive predictive value compared to impaired FVC, particularly in non-smoker patients. The most frequent HRCT finding was ground-glass attenuation (64.3%). Other common findings were bronchiectasis, reticular pattern and honeycombing. The lesions involved predominantly the lower lobes. In conclusion, the presence of hypergammaglobulinemia and lymphopenia, positivity for RF, anti-La and anti-Ro, and impaired (FVC) and/or FEV(1) values could be the predictive parameters with a high specificity despite the low sensitivity rates. Smoking history, male gender and age are also risk factors. These parameters may be helpful to distinguish pSS-associated lung involvement from lung disorders unrelated to pSS.

Thoracic epidural anesthesia for laparoscopic cholecystectomy in an elderly patient with severely impaired pulmonary function tests

Regional anesthesia for laparoscopic cholecystectomy has been reported in patients with severe respiratory disease and is a safe alternative to general anesthesia. Hemodynamic instability can occur on initiating pneumoperitoneum and the respiratory acidosis can last into the post-operative period without careful monitoring and management. This case report describes such an episode in an elderly patient with severely impaired respiratory function who was given thoracic epidural anesthesia for laparoscopic cholecystectomy.

Smoldering systemic inflammation: a link between schizophrenia, smoking and obesity

Smoldering systemic inflammation: a link between schizophrenia, smoking and obesity

Management and implications of chronic obstructive pulmonary disease (COPD) for older patients

Airflow obstruction is common in older persons but frequently under-diagnosed. The term refers to a spectrum of chronic respiratory disorders characterized by cough, dyspnoea, mucus hypersecretion, wheeze and impaired pulmonary function tests. Patients may be diagnosed as having late-onset asthma, chronic obstructive pulmonary disease (COPD), chronic bronchitis, emphysema or fixed airflow obstruction of the elderly.

Silica-associated connective tissue disease. A study of 24 cases.

We prospectively studied all patients hospitalized for connective tissue disease (CTD) in our French rheumatology clinic from January 1979 to December 1989. Our aims were 1) to determine if CTDs associated with occupational exposure to silica (Si) are currently observed in a rheumatology clinic, and, if so, 2) to describe the major features of Si-associated CTD, and 3) to specify which individuals are affected by Si-associated CTD. Patients were divided into 2 groups based on their responses to a questionnaire: those who had been exposed to Si, and those who had no occupational exposure to Si. Among the 764 patients with CTD studied, 24 (3%) were patients with Si-associated CTD and 740 (97%) were patients with non-Si-associated CTD. The sex ratio between the 2 groups was significantly different with a high frequency of men and of immigrants in the Si-associated CTD group. Two thirds of the patients exposed to Si were male miners or sandblasters, but the other third had more unusual exposures to Si, which may involve members of all socio-economics sectors and both sexes, such as sculpture or exposure to abrasive powders. Progressive systemic sclerosis (PSS) was significantly more prevalent in the Si-associated CTD group. This group also consisted of patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), dermatomyositis (DM), and other autoimmune diseases. Si-associated CTD was characterized by the frequency of radiologic lung fibrosis, impaired pulmonary function tests, secondary Sjögren syndrome, and antinuclear antibodies. The number of mineral particles and crystalline Si content were raised in all the bronchoalveolar lavage specimens of Si-exposed patients but in none of those of nonexposed patients. In some cases of Si-associated CTD, the disease was reversible after early cessation of Si exposure. Epidemiologic studies are required to confirm our hypothesis that not only PSS and RA but also SLE and DM are associated with occupational exposure to Si. Pending such results, exposure to Si should be sought in the history of any patient with CTD, especially in a male patient with pulmonary signs, and if present, exposure should be stopped. In the meantime, steps should be taken to ensure that workers exposed to Si in all environments have adequate protection.

高齢者，開腹手術の術後合併症に関する術前危険因子の検討

In order to evaluate the prognostic importance of the conditions before abdominal surgery for patients over 60 years of age. Multivariate analyses of postoperative complications were performed in 634 patients (comprising 525 cases of elective abdominal surgery and 109 cases of emergency abdominal surgery). The Mortality rate was significantly higher (p < 0.01) in the emergency group (11.9%) and relatively low among the elective abdominal surgery group (3.8%). In the emergency group, 13 patients died, and MOF (multiple organ failure) was found to be the direct cause of death in 11 (85%). Although, the majority (75%) of emergency operations were for benign disorders, the remainder (25%) had malignant tumors. It is noteworthy that among 25% of cases, obstructions and perforations due to large bowel cancers were found to be 59% and 19%, respectively. In the elective surgery group, postoperative pulmonary and cardiovascular complications were found in 11.6% and 9.6%, respectively. Death due to cardiovascular problems in rare (5%), however, postoperative pneumonia was the cause of death in 70% of all of postoperative death. Risk factors affecting postoperative pulmonary complications were malnutrition, advanced age, male sex, malignant disease, dementia, cerebrovascular disorders, impaired pulmonary function tests. Surprisingly, the risk factors were identical, except for impaired pulmonary function, for postoperative MRSA pneumonia. In our study, postoperative pulmonary death was not associated with impaired pulmonary function, and it appears to be rather affected by the presence of cerebrovascular disorders and malnutritional state. A poor nutritional states (< 40 according to Onodera's nutritional index) was present in over 50% of patients with cerbrovascular disorders and low ADL.(ABSTRACT TRUNCATED AT 250 WORDS)

Arterial oxygen desaturation during esophagogastroduodenoscopy.

This prospective study evaluated the incidence and severity of arterial oxygen desaturation during esophagogastroduodenoscopy (EGD) and assessed clinical factors in relation to arterial oxygen desaturation. Following pulmonary function testing, 192 patients underwent elective EGD with continuous recording of arterial oxygen saturation (SaO2). 62 patients (32.3%) showed arterial oxygen desaturation (SaO2 decrease greater than 4% from baseline SaO2); severe arterial oxygen desaturation (SaO2 less than or equal to 85%) reflecting hypoxemia (arterial oxygen tension less than or equal to 50 mmHg) was found in 17 patients (8.9%). These changes were most frequent at the esophageal stage of EGD but most marked at the gastroduodenal stage of EGD. The incidence of arterial oxygen desaturation was not related to age, sex, preendoscopic pulmonary function tests, smoking, or duration of endoscopy. These data support that continuous monitoring of SaO2 should be standard procedure during endoscopy because there was no identifiable preendoscopic risk factor for arterial oxygen desaturation during EGD. But there was no persistent drop in SaO2 longer than 2 minute. We suppose that oxygen supplement may not be required during EGD even in patients with modestly impaired pulmonary function tests.

Effects of inhibition of thromboxane A 2 synthesis in aspirin-induced asthma

Since inhibition of cyclooxygenase precipitates asthmatic attacks in patients with aspirin idiosyncrasy, we have evaluated the effects of pharmacologic inhibition of thromboxane A2 (TXA2) synthetase, next to cyclooxygenase enzyme in arachidonic acid cascade. Sixteen patients with aspirin-induced asthma received increasing doses on 3 days (25 to 400 mg) of an imidazole derivative, OKY-046, which specifically blocks TXA2 synthetase. Twenty-three healthy control subjects received a single dose of 400 mg of OKY-046. In both patients and control subjects, the inhibitor at a dose of 400 mg produced (1) a pronounced fall in thromboxane B2 serum levels, (2) a rise in serum 6-keto-prostaglandin F1 alpha, and (3) a depression in platelet aggregability to arachidonic acid and adenosine diphosphate. The drug, however, neither precipitated attacks of asthma nor impaired pulmonary function tests throughout a 24-hour observation period. Five patients, but none of the control subjects, developed transient nasal congestion about 1 hour after taking the drug. Thus, inhibition of TXA2 synthetase, contrary to inhibition of cyclooxygenase, does not affect bronchopulmonary function in patients with asthma and aspirin intolerance.