Blog
About

6
views
0
recommends
+1 Recommend
1 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Is cardiac autonomic modulation during upper limb isometric contraction and Valsalva maneuver impaired in COPD patients?

      Read this article at

      ScienceOpenPublisherPMC
      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Purpose

          To evaluate the heart rate variability (HRV) indices and heart rate (HR) responses during isometric contraction (IC) and Valsalva maneuver (VM) in COPD patients.

          Methods

          Twenty-two stable moderate to severe COPD patients were evaluated. R-R intervals were recorded (monitor Polar ® S810i) during dominant upper limb IC (2 minutes). Stable signals were analyzed by Kubios HRV ® software. Indices of HRV were computed in the time domain (mean HR; square root of the mean squared differences of successive RR intervals [RMSSD] and HRV triangular index [RR tri index]) and in the frequency domain (high frequency [HF]; low frequency [LF] and LF/HF ratio). The HR responses were evaluated at rest, at the peak and at the nadir of the VM (15 seconds). The Valsalva index was also calculated.

          Results

          During IC: time domain indices (mean HR increased [ P=0.001], RMSSD, and RR tri index decreased [ P=0.005 and P=0.005, respectively]); frequency domain indices (LF increased [ P=0.033] and HF decreased [ P=0.002]); associations were found between forced expiratory volume in 1 second (FEV 1) vs RMSSD ( P=0.04; r=−0.55), FEV 1 vs HR ( P=0.04; r=−0.48), forced vital capacity (FVC) vs RMSSD ( P=0.05; r=−0.62), maximum inspiratory pressure (MIP) vs HF ( P=0.02; r=0.68). FEV 1 and FVC justified 30% of mean HR. During VM: HR increased ( P=0.01); the nadir showed normal bradycardic response; the Valsalva index was =0.7.

          Conclusion

          COPD patients responded properly to the upper limb IC and to the VM; however, HR recovery during VM was impaired in these patients. The severity of the disease and MIP were associated with increased parasympathetic modulation and higher chronotropic response.

          Related collections

          Most cited references 34

          • Record: found
          • Abstract: found
          • Article: not found

          New reference values for forced spirometry in white adults in Brazil.

          To describe spirometric reference equations for healthy Brazilian adults who have never smoked and to compare the predicted values with those derived in 1992. Reference equations for spirometry were derived in 270 men and 373 women living in eight cities in Brazil. Ages ranged from 20 to 85 years in women and from 26 to 86 years in men. Spirometry examinations followed the recommendations of the Brazilian Thoracic Society. Lower limits were derived by the analysis of the fifth percentiles of the residuals. Forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC and FEV1/forced expiratory volume in six seconds (FEV6) were best fitted by linear regression. Flows were best fitted using log equations. For both genders, greater height resulted in lower values for FEV1/FVC, FEV1/FEV6 and flow/FVC ratios. The reference values for FEV1 and FVC in the present study were higher than those derived for Brazilian adults in 1992. New predicted values for forced spirometry were obtained in a sample of white Brazilians. The values are greater than those obtained in 1992, probably due to technical factors.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Reference values for lung function tests. II. Maximal respiratory pressures and voluntary ventilation.

            The strength of the respiratory muscles can be evaluated from static measurements (maximal inspiratory and expiratory pressures, MIP and MEP) or inferred from dynamic maneuvers (maximal voluntary ventilation, MVV). Although these data could be suitable for a number of clinical and research applications, no previous studies have provided reference values for such tests using a healthy, randomly selected sample of the adult Brazilian population. With this main purpose, we prospectively evaluated 100 non-smoking subjects (50 males and 50 females), 20 to 80 years old, selected from more than 8,000 individuals. Gender-specific linear prediction equations for MIP, MEP and MVV were developed by multiple regression analysis: age and, secondarily, anthropometric measurements explained up to 56% of the variability of the dependent variables. The most cited previous studies using either Caucasian or non-Caucasian samples systematically underestimated the observed values of MIP (P < 0.05). Interestingly, the self-reported level of regular physical activity and maximum aerobic power correlates strongly with both respiratory and peripheral muscular strength (knee extensor peak torque) (P < 0.01). Our results, therefore, provide a new frame of reference to evaluate the normalcy of some useful indexes of respiratory muscle strength in Brazilian males and females aged 20 to 80.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Heart rate variability in healthy subjects: effect of age and the derivation of normal ranges for tests of autonomic function.

              The diagnosis of autonomic neuropathy frequently depends on results of tests which elicit reflex changes in heart rate. Few well-documented normal ranges are available for these tests. The present study was designed to investigate the effect of age upon heart rate variability at rest and in response to a single deep breath, the Valsalva manoeuvre, and standing. A computerised method of measurement of R-R interval variation was used to study heart rate responses in 310 healthy subjects aged 18-85 years. Heart rate variation during each procedure showed a skewed distribution and a statistically significant negative correlation with age. Normal ranges (90% and 95% confidence limits) for subjects aged 20-75 years were calculated for heart rate difference (max-min) and ratio (max/min) and standard deviation (SD). Heart rate responses were less than the 95th centile in at least one of the four procedures in 39 (12.6%) out of the 310 subjects, and were below this limit in two or more tests in five (1.6%) subjects. In view of the decline in heart rate variation with increasing age, normal ranges for tests of autonomic function must be related to the age of the subject.
                Bookmark

                Author and article information

                Journal
                Int J Chron Obstruct Pulmon Dis
                Int J Chron Obstruct Pulmon Dis
                International Journal of COPD
                International Journal of Chronic Obstructive Pulmonary Disease
                Dove Medical Press
                1176-9106
                1178-2005
                2017
                13 March 2017
                : 12
                : 849-857
                Affiliations
                [1 ]Course of Physiotherapy, University of Santa Cruz do Sul, Rio Grande do Sul, Brazil
                [2 ]Cardiopulmonary Physiotherapy Laboratory, Nucleus of Research in Physical Exercise, Federal University of São Carlos, São Carlos, Brazil
                [3 ]Department of Physiotherapy, Federal University of Amazonas, Manaus, AM, Brazil
                [4 ]Course of Physiotherapy, Department of Health and Physical Education, University of Santa Cruz do Sul, Rio Grande do Sul, Brazil
                [5 ]Pulmonary Rehabilitation Program, Santa Cruz Hospital, Santa Cruz do Sul, Rio Grande do Sul, Brazil
                Author notes
                Correspondence: Andréa Lúcia Gonçalves da Silva, Rua Vereador Benno Kist, 1780/15, Bairro Santo Inácio, Santa Cruz do Sul, RS, CEP 96820-688, Brazil, Tel +55 51 3717 7374, Email andreag@ 123456unisc.br
                Article
                copd-12-849
                10.2147/COPD.S130428
                5357074
                © 2017 Goulart et al. This work is published and licensed by Dove Medical Press Limited

                The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License ( http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed.

                Categories
                Original Research

                Comments

                Comment on this article