Alternative field exercise tests for people with respiratory conditions

Stair-climbing test as a physical performance tool in chronic heart failure: Association with left ventricular ejection fraction and pulmonary functions

OBJECTIVE

The cardiopulmonary exercise test (CPET), which is used as the gold standard in the evaluation of exercise capacity in patients with chronic heart failure (CHF), is not always possible to perform in clinics and field tests are preferred. The aim of this study was to determine the effectiveness of the symptom-limited stair climbing test (SLSCT) in patients with CHF.

METHODS

Thirty-one patients (mean age: 65.52±7.57 years) with New York Heart Association (NYHA) Classification stage II-III CHF were included. Exercise capacity was assessed by SLSCT, 6-minute walk test (6MWT), and CPET. Predicted peak oxygen consumption (VO2peak), heart rate (HR), blood pressure (BP), and left ventricular ejection fraction (LVEF), pulmonary functions were measured.

RESULTS

The predicted VO2peak calculated from SLCT was significantly higher than that of 6MWT and CPET (p<0.05). On analyzing the HR changes, SLSCT increased HR by more than 6MWT and less than CPET (p<0.05). There were significant correlations between the predicted VO2peak values by SLSCT and LVEF, BMI (Body Mass Index), FEV1 (Forced Expiratory Volume in One Second), and FVC (Forced Vital Capacity), predicted VO2peak of CPET (r=0.36-0.55, p≤0.05).

CONCLUSION

SLSCT was found to be effective and easy to use in assessing exercise capacity in CHF patients. Compared with 6MWT, SLSCT gives better results in determining the clinical status and hemodynamic responses of the patients. SLSCT can be an alternative method for assessing exercise capacity in the absence of CPET.

One minute sit-to-stand test as a potential triage marker in COVID-19 patients: A pilot observational study

Background

The crisis of critical care resource allocation during the novel coronavirus infectious disease 2019 (COVID-19) pandemic has underscored the importance of triage. COVID-19 is associated with increased hypoxemia and desaturation on exertion. We hypothesized that desaturation after 1-min sit-to-stand test (1MSTS), a validated field exercise test can serve as a potential marker for triage of COVID 19 patients.

Methods

Subjects with proven COVID 19 without hypoxemia on ambient air at presentation underwent the 1MSTS. The demographic details, clinical profile, pre and post-test vitals and pulse oximetric saturation was recorded and they were followed up for outcome throughout the hospital stay and after discharge.

Results

55 mild cases of COVID-19 and 6 cases of recovering severe COVID-19 were included. The mild cohort had a median age of 35 years (IQR, 27-41.5) and a median hospital stay of 16 days (IQR 14,20). The severe cohort had a median age of 47.5 years (IQR, 42.3,54.3) and median intensive care and hospital stays of respectively 9 (IQR, 7.5,9) and 23.5 (IQR, 21.5,27) days. The two cohorts showed median desaturations of 0% (IQR, 0.5-1) and 5.5% (IQR, 4.3-6) respectively. No subjects in the mild cohort needed oxygen therapy or escalation of care to intensive care.

Conclusions

Significant desaturation after 1-MSTSin severe COVID 19 patients demonstrates the potential role of 1-MSTS both in triage for planning care and as a discharge criteria from intensive care unit. However, larger prospective studies are warranted for its evaluation and establishment of relevant cut-offs.

Direct and indirect evidence of efficacy and safety of rapid exercise tests for exertional desaturation in Covid-19: a rapid systematic review

BACKGROUND

Even when resting pulse oximetry is normal in the patient with acute Covid-19, hypoxia can manifest on exertion. We summarise the literature on the performance of different rapid tests for exertional desaturation and draw on this evidence base to provide guidance in the context of acute Covid-19.

MAIN RESEARCH QUESTIONS

1. What exercise tests have been used to assess exertional hypoxia at home or in an ambulatory setting in the context of Covid-19 and to what extent have they been validated? 2. What exercise tests have been used to assess exertional hypoxia in other lung conditions, to what extent have they been validated and what is the applicability of these studies to acute Covid-19?

METHOD

AMED, CINAHL, EMBASE MEDLINE, Cochrane and PubMed using LitCovid, Scholar and Google databases were searched to September 2020. Studies where participants had Covid-19 or another lung disease and underwent any form of exercise test which was compared to a reference standard were eligible. Risk of bias was assessed using QUADAS 2. A protocol for the review was published on the Medrxiv database.

RESULTS

Of 47 relevant papers, 15 were empirical studies, of which 11 described an attempt to validate one or more exercise desaturation tests in lung diseases other than Covid-19. In all but one of these, methodological quality was poor or impossible to fully assess. None had been designed as a formal validation study (most used simple tests of correlation). Only one validation study (comparing a 1-min sit-to-stand test [1MSTST] with reference to the 6-min walk test [6MWT] in 107 patients with interstitial lung disease) contained sufficient raw data for us to calculate the sensitivity (88%), specificity (81%) and positive and negative predictive value (79% and 89% respectively) of the 1MSTST. The other 4 empirical studies included two predictive studies on patients with Covid-19, and two on HIV-positive patients with suspected pneumocystis pneumonia. We found no studies on the 40-step walk test (a less demanding test that is widely used in clinical practice to assess Covid-19 patients). Heterogeneity of study design precluded meta-analysis.

DISCUSSION

Exertional desaturation tests have not yet been validated in patients with (or suspected of having) Covid-19. A stronger evidence base exists for the diagnostic accuracy of the 1MSTST in chronic long-term pulmonary disease; the relative intensity of this test may raise safety concerns in remote consultations or unstable patients. The less strenuous 40-step walk test should be urgently evaluated.

Modified Chester Step Test in a Healthy Adult Population: Measurement Properties and Development of a Regression Equation to Estimate Test Duration

OBJECTIVE

Healthy working-aged adults performed the modified Chester Step Test (mCST) to (1) determine the effect of repetition on test duration, (2) report cardiorespiratory and symptom responses, (3) establish a regression equation to estimate duration, and (4) calculate the minimal detectable change of the test.

METHODS

In this observational study conducted in a hospital physical therapy, adult participants aged 25 to 65 years who were healthy performed the mCST twice. This submaximal test required participants to step on and off a 20-cm step at a standardized cadence that increased every 2 minutes. The criteria for test completion were either a heart rate equal to 80% of age-predicted maximum or the onset of intolerable symptoms. The primary measure was time to test completion during the mCST (seconds). Cardiorespiratory and symptom responses were also collected during the mCST.

RESULTS

A total of 83 participants (40 men, mean [SD] age = 44 [12] years) completed data collection. There was no systematic effect of test repetition with median test duration of the first test (522 seconds, range = 400-631 seconds) and second test (501 seconds, range = 403-631 seconds). The test elicited moderate symptoms of breathlessness and leg fatigue. In the multivariable model, age, sex, weight, and height were retained as significant predictors of test duration (R2 = 0.48). The minimal detectable change was 119 seconds.

CONCLUSIONS

The mCST is a reliable and valid clinically applicable test of aerobic capacity in working-aged adults. Independent pretest predictors can be used to estimate the clinical time required to complete the test.

IMPACT

The mCST was stable between test repetitions, suggesting no learning effect. For any given individual, a test duration change of 2 minutes represents change was beyond the natural variability. The mCST has good applicability to clinical settings.

Reliability of the five-repetition sit-to-stand test in patients with chronic obstructive pulmonary disease on domiciliary oxygen therapy

Objectives: To evaluate the reliability and learning effect of the five-repetition sit-to-stand test (5STSt) in severe and very severe chronic obstructive pulmonary disease (COPD) patients on domiciliary oxygen therapy compare the results with those of COPD patients not on such therapy. Methods: Twenty-eight COPD patients were included in the domiciliary oxygen therapy group (DOTG) and 17 in the control group (CG). The participants of the groups were paired by age, sex, body mass index, and lung function. The groups performed two 5STSt (5STSt₁ and 5STSt₂). Results: In total, 96% of the patients in the DOTG performed better on the second 5STSt (5STSt₂) (17.1 ± 4.63s), with an average reduction of 3.87 ± 3.50 s (p < 0.001) and a learning effect of 18.4%. In the CG, 82.3% of patients had better performance on the 5STSt₂ (15.06 ± 3.45 s), with an average reduction of 1.38 ± 2.51 s (p = 0.035) and a learning effect of 8.39%. The 5STSt had an ICC of 0.79 (95%CI: 0.02-0.93; p < 0.001) in the DOTG and of 0.89 (95%CI: 0.65-0.96; p < 0.001) in the CG. Conclusion: The 5STSt is reliable in patients with severe and very severe COPD on domiciliary oxygen therapy, with learning effect of nearly 18% in the DOTG. Thus, performing two tests is recommended to achieve the patient´s best performance in this population.