Application of impulse oscillometry in respiratory system evaluation in elderly patients.

INTRODUCTION: Spirometry, which is a basic diagnostic tool of the respiratory system, may cause problems to patients of advanced age because of required cooperation and specific respiratory manoeuvres. Impulse oscillometry (IOS) may be an interesting alternative for spirometry as the examination is made during quiet breathing and gives information about resistive properties of the respiratory system. MATERIAL AND METHODS: This work presents the results of oscillometric measurements made in 277 patients aged 65-96 years, in whom spirometry was also performed. RESULTS: Resistances measured with IOS (R5, R5-R20) and the resonant frequency Fn correlated significantly with FEV1 (r = -0.503; -0.570 and -0.673, respectively). A comparison of the results from patients with airway obstruction confirmed in spirometry with those of the non-obstructed group showed highly significant differences in mean values of oscillometric parameters (p < 0.001). CONCLUSIONS: As R5-R20 is regarded as a measure of peripheral airways resistance, IOS may serve as an interesting complementary or alternative method for spirometry in elderly subjects for evaluation of the state of respiratory system.

Quality of spirometry in the elderly.

INTRODUCTION: Spirometry is the basic method used to diagnose and monitor obstructive diseases. Spirometric tests are performed in more and more people of advanced age (more than 65 years old). The objective of the study was to assess the quality of spirometry (measurement of the flow-volume curve) in subjects of the aforementioned age group, with reference to applicable quality criteria specified in guidelines ERS/ATS 2005 and PTChP 2006. MATERIAL AND METHODS: The study was of a retrospective nature. The authors analysed the results of spirometry performed in 1271 subjects who were 65 to 94 years old and who underwent spirometric tests in the Respiratory Physiopathology Laboratory of Kujawy-Pomorze Regional Centre of Pulmonology in Bydgoszcz over a period of 6 months. This group included 759 males (average age 73.2 ± 5.9 years) and 512 females (average age 73.2 ± 5.7 years). The quality of the spirometry was assessed according to error codes assigned to individual spirometric sessions by the software JLab 5.31 installed in the measuring system MasterScreen (CareFusion). RESULTS: Twenty-nine (2.3%) of the 1271 subjects failed to perform spirometric measurements. For the remaining 1242 subjects the following spirometry quality was determined: correctly performed spirometric test in 415 (33.4%) subjects; one error in 673 (54.2%) subjects; 2 errors in 136 (11%) subjects; 3 errors in 15 (1.2%) subjects and 4 errors in 3 (0.2%) subjects. The analysis of individual errors revealed that the lack of a plateau at the end of exhalation was found in 747 (60.1%) subjects (including only 25 (2%) subjects with FET < 6 s); increased BEV value in 7 (0.6%) subjects; abruptly finished exhalation in 36 (2.9%) subjects; and no FVC and FEV1 repeatability in 43 (3.5%) and 169 (13.6%) subjects, respectively. CONCLUSIONS: The most common error was the lack of a plateau at the end of exhalation. Therefore, paying particular attention to the final phase of exhalation during spirometry should, as a result, increase the percentage of correctly performed spirometric tests in the elderly.

Sleep problems among children with Fetal Alcohol Spectrum Disorders (FASD)- an explorative study.

BACKGROUND: Fetal alcohol spectrum disorders (FASD) is a group of conditions resulting from prenatal alcohol exposure (PAE). Patients with FASD experience a variety of neuropsychological symptoms resulting from central nervous system impairment. Little is known about sleep disorders associated with PAE. The objective of this study was to investigate sleep problems related to FASD. METHODS: Forty patients (median age 8 years (6; 11)) diagnosed with FASD and forty typically developing children (median age 10 years (8; 13)) were recruited for the 1st phase of the study. In the 1st phase, the screening of sleep problems was performed with Child Sleep Habit Questionnaire (CSHQ) filled in by a caregiver. Those of the FASD group who scored above 41 points were qualified to the 2nd phase of the study and had an in-lab attended polysomnography (PSG) performed. The measurements consisted of electroencephalogram, electrooculograms, chin and tibial electromyogram, electrocardiogram, ventilatory monitoring, breathing effort, pulse oximetry, snoring and body position. Their results were compared to PSG laboratory reference data. RESULTS: The number of participants with sleep disturbances was markedly higher in the FASD group as compared to typically developing children (55% vs. 20%). The age-adjusted odds ratio for a positive result in CSHQ was 4.31 (95% CI: 1.54-12.11; p = 0.005) for FASD patients as compared to the control group. Significant differences between the FASD as compared to the typically developing children were observed in the following subscales: sleep onset delay, night wakings, parasomnias, sleep disordered breathing, and daytime sleepiness. Children from the FASD group who underwent PSG experienced more arousals during the sleep as compared with the PSG laboratory reference data. The respiratory indices in FASD group appear higher than previously published data from typically developing children. CONCLUSION: The results support the clinical observation that sleep disorders appear to be an important health problem in individuals with FASD. In particular distorted sleep architecture and apneic/hypopneic events need further attention.

Spirometry during the SARS-CoV-2 pandemic. Guidelines and practical advice from the expert panel of Respiratory Physiopathology Assembly of Polish Respiratory Society.

At the end of 2019, in Wuhan, the Hubei Province's capital city in China, the first cases of COVID-19 disease caused by the novel coronavirus, SARS-CoV-2, were described. The rapid spread of the infection through the world resulted in the World Health Organization announcing the COVID-19 a global pandemic in March 2020. The main routes of transmission of the novel coronavirus SARS-CoV-2, according to current evidence, are via droplets inhalation, direct contact with contaminated surfaces, and transmission via the mucous membranes of the mouth, nose, and eyes, and probably through airborne particles from the respiratory tract, generated during coughing and sneezing of infected individuals. During the pulmonary function testing (PFTs), which require strenuous breathing maneuvers and generate high-intensity airflow, aerosols, and micro-aerosols are formed from respiratory secretions and may contain viral and bacterial particles. Therefore, such forced respiratory maneuvers pose a significant risk of spreading the infection to patients and laboratory staff. According to current knowledge, the source of infection may also be an asymptomatic and a pre-symptomatic individual. Coronavirus SARS-CoV-2 has been increasingly prevalent in the community, and this increases a potential risk to all patients tested lung function and staff working there. As the patients' and staff's safety is of unprecedented importance, the additional precautions when performing pulmonary function tests are necessary and unquestionable. In consequence, the greater availability of consumables and personal protective equipment is indispensable. The reorganization of daily practice will prolong test time, reduce the number of tests performed, and slow down patients' flow. The guidance provides practical advice to health care professionals on performing pulmonary function tests during the COVID-19 pandemic. It has been developed basing on currently available information and recommendations from relevant health care institutions. As the COVID-19 pandemic is a rapidly evolving situation and the new scientific data has been becoming are available, the guidance will be updated over time.

[The management of obstructive sleep apnea syndrome in drivers - recommendations of the Polish Society Of Occupational Medicine, The Polish Respiratory Society, The Nofer Institute of Occupational Medicine in Lodz and The Polish Sleep Research Society]. / Postepowanie lekarskie w obturacyjnym bezdechu sennym u osób kierujacych pojazdami − zalecenia Polskiego Towarzystwa Medycyny Pracy, Polskiego Towarzystwa Chorób Pluc, Instytutu Medycyny Pracy w Lodzi i Polskiego Towarzystwa Badan nad Snem.

The findings of numerous studies and analyzes conducted in many countries have proven that obstructive sleep apnea (OSA) negatively affects the psychophysical abilities drivers. Therefore, in Commission Directive 2014/85/EU of July, 1 2014, OSA was recognized as one of the most important risk factors for car accidents. The implementation of said Directive by Member States is to contribute to reducing the risk of such accidents. The implementation of the Directive in Poland has resulted in enacting the Ordinance of the Minister of Health of December 23, 2015 amending the ordinance on medical examinations of applicants for a driving license and drivers. Although Annex 2 to that regulation sets out the detailed conditions for a medical examination for OSA, it does not regulate or clarify the issue of tools and methods for suspecting OSA in a moderate or hard form. Therefore, it was necessary to develop standards of management for doctors authorized to perform medical examinations of drivers and applicants for a driving license in the case of suspected OSA. The paper presents an algorithm of proceedings that streamlines the case-law process in the above-mentioned cases, which was developed by the Polish Society of Occupational Medicine in cooperation with the Polish Respiratory Society, the Nofer Institute of Occupational Medicine in Lódz and the Polish Sleep Research Society. Med Pr. 2020;71(2):233-43.

[Quality of spirometric measurements in children younger than 10 years of age in the light of the recommendations]. / Jakosc badania spirometrycznego u dzieci 10-letnich i mlodszych w swietle zalecen standaryzacyjnych.

INTRODUCTION: In 2005 the European Respiratory Society/American Thoracic Society (ERS/ATS) published an updated document on the standardization of spirometry (European Respiratory Journal 2005; 26: 319-338). It defines criteria for the acceptability of spirometric measurements. The aim of this retrospective study was to assess the adherence to those standards of flow-volume measurements in children younger than 10 years of age. MATERIAL AND METHODS: The analysis was carried out on the results obtained from 233 children aged 4.2-10 years, referred to a spirometric lab during a period of three months. RESULTS: 116 children (all but one preschool) did not cooperate; the results of the 117 who completed the procedure of flow-volume measurement were analysed using ERS/ATS criteria. 80.3% of the children had back extrapolated volume (Vbe) within the defined limit, but only 23.9% had forced expiratory time > 3 s. FEV(1) and FVC were repeatable in 78.6% of the children. When these three criteria were used together, the measurements were acceptable according to ATS/ERS recommendations in 17.1% of the children. Elimination of the forced expiratory time criterion has further increased their number to 63.2%. CONCLUSIONS: Specific recommendations for children should be developed, as the current requirements appear too restrictive, especially regarding the time of forced expiration.

Impulse oscillometry vs. body plethysmography in assessing respiratory resistance in children.

In 334 children aged 5-18 years, we compared the results of plethysmographic measurements of airway resistance (Raw) with oscillometric (impulse oscillometry; IOS) assessment of respiratory properties of the respiratory system (resistance (R) at 5, 20, and 35 Hz). All three resistances correlated significantly with plethysmographic Raw, and the strongest correlation was seen for R5 (r = 0.64). R5, R20, and R35 were significantly greater than Raw in the whole group. In the group of children with obstruction (FEV(1)%FVC below lower limit of normal), R5 was still greater than Raw, while R20 and R35 were not. The Bland-Altman analysis comparing plethysmographic measurements with oscillometric R5 revealed a significant difference between Raw and R5 in the whole group, which disappeared in the group of obstructed patients. Oscillometric assessment of resistive properties of the respiratory system of the lung requires less patient cooperation than does plethysmography. As the results of measurements using oscillometric R5 are similar to those obtained by plethysmography, IOS may be useful in diagnosing children with obstructive respiratory diseases.

Reference values for forced inspiratory flows in children aged 7-15 years.

In order to construct reference equations, we attempted to measure forced inspiratory flows, i.e., peak inspiratory flow (PIF) and maximal inspiratory flow at 50% of FVC (MIF50%FVC) in 332 healthy schoolchildren aged 7-15 years during flow-volume loop measurements, using an electronic spirometer. In 255 children (122 boys and 133 girls), the results were satisfactory. Statistical analysis revealed that the only predictive variables were sex and height. The best fit of the data was obtained with the power model (Y = A * H(B)); the coefficients of correlation between flows and height ranged from 0.66-0.77, and were slightly greater for boys. Forced inspiratory flows in children increase with height, and the variability is higher than for forced expiratory flows. Reference values for forced inspiratory flows can be useful in assessing the ability of children to generate affective inspiratory flows for choosing an inhalation device, or in resolving diagnostic problems, e.g., extrathoracic obstruction.

A double-blind, crossover study of Doxazosin and Enalapril on peripheral vascular tone and nocturnal blood pressure in sleep apnea patients.

OBJECTIVE: Pulse wave attenuation, which occurs in association with obstructive sleep apnea (OSA), is sympathetically mediated. We compared the effect of Doxazosin (DO, a peripheral alpha-receptor inhibitor) and Enalapril (EN, an ACE inhibitor) on digital vasoconstriction and nocturnal blood pressure (BP) in hypertensive OSA patients. METHODS: A double-blind, crossover study comparing equipotent dosages of DO (4 mg/day for 2 weeks with 8 mg/day for an additional 2 weeks) and EN (10mg/day and 20mg/day, respectively) was undertaken in 16 male OSA patients (age 55+/-7 years, body mass index 30.1+/-3.8 kg/m(2)) with hypertension. Assessments including ambulatory 24-h BP, full-night polysomnography with simultaneous peripheral arterial tone (PAT) and beat-to-beat finger BP monitoring (Finapres) were made at the end of each treatment period. Nighttime BP and digital vasoconstrictions associated with apneic events (measured as the ratio of PAT amplitudes during and after apneas) were analyzed. RESULTS: There were no differences between the two treatments in the 24-h BP profile and OSA severity. But the nighttime average beat-to-beat finger BP was significantly higher under DO treatment (systolic BP 129+/-13 vs. 119+/-23 mm Hg, P=0.02; diastolic BP 81+/-12 vs. 74+/-14 mm Hg, P=0.04, DO and EN respectively). In a linear mixed effects regression model, the PAT ratio during apnea increased 5.3% under DO compared with EN (P<0.0001). Each percentage decrease of apneic related oxygen desaturation was associated with 0.9% decrease in the PAT ratio (P<0.0001). REM sleep was associated with 2.2% decrease of PAT ratio compared to NREM sleep (P=0.002). CONCLUSION: Digital vasoconstrictions associated with apneic events are alpha-receptor mediated. DO compared to EN has a proportionally poor effect on nocturnal BP control in OSA patients, which may be due to the enhanced sympathetic nervous system activity characteristic of this condition.

Nocturnal pulse wave attenuation is associated with office blood pressure in a population based cohort.

OBJECTIVE AND BACKGROUND: Pulse wave amplitude (PWA) derived from the digital vascular bed has been used in sleep studies. The nocturnal attenuation of PWA has been shown to reflect sympathetic activation during sleep. We assessed the relationship between nocturnal PWA attenuation and office blood pressure (BP). METHODS: Eighty-one subjects (46 men; age 60+/-7 years; body mass index [BMI] 28.2+/-4.3 kg/m(2); apnea hypopnea index [AHI], 25.4+/-22.6 events/h; systolic BP 137+/-15 mm Hg; diastolic BP 79+/-7 mm Hg) recruited from a population based cohort underwent simultaneous ambulatory polysomnography (PSG) and peripheral arterial tonometry (PAT) recording. Episodic attenuations of PWA derived from the pulse waveform of the PAT signal were identified and characterized. Generalized least squares regression models were used to identify the associations between median PWA attenuation (PWA.att), office BP and sleep-related disordered breathing. RESULTS: We found that the association between PWA.att and office BP was independent of gender, age, BMI, antihypertensive medication, number of attenuation episodes, AHI, oxygen desaturation 4% index (ODI4) and arousal index. Each 10% increase in PWA.att was associated with increases of 5.0 mm Hg systolic BP (P=0.02) and 3.0 mm Hg diastolic BP (P=0.005). We also found independent relationships between systolic/diastolic BP and BMI (P=0.0006/0.001), AHI (P=0.03/0.1) and ODI4 (P=0.03/0.03). CONCLUSIONS: The degree of PWA attenuation during the night is associated with office BP independent of sleep-disordered breathing. Continuous assessment of PWA during sleep may provide novel insights into cardiovascular physiology and morbidity.

Transient reference values for impulse oscillometry for children aged 3-18 years.

Impulse oscillometry (IOS) is a technique of assessing mechanical properties of respiratory system by means of measuring resistances and reactances in a number of frequencies during tidal breathing. It is especially useful in preschool children, however has also been validated in older children and adults. The aim of the present study was to construct equations describing normal values of oscillatory parameters in pediatric population of healthy polish children. Six hundred twenty-six healthy children aged 3.1-18.9 years (278 boys and 348 girls) completed the study. Analysis revealed that body height was the best predictor and resistances are best described with exponential model while reactances with linear one, with correlation coefficient r reaching the value of 0.9. Oscillometric resistances decrease with height, while reactances increase. Reference values for children and adolescents will allow not only the interpretation of the measurement, but also will make possible to study changes of oscillometric indices during growth.