Six minute walking distance in kyphoscoliosis patients with chronic respiratory failure

Abstract

AimTo evaluate kyphoscoliosis patients with chronic hypercapnic respiratory failure (CHRF) using the six minute walk test (6MWT) distance (6MWD) and cardio-pulmonary function tests.MethodThis prospective cross-sectional study was carried out in a tertiary training and research hospital in Turkey. Kyphoscoliosis patients with CHRF on home mechanical ventilation (HMV) followed in a respiratory intensive care unit (RICU) out-patient clinic were enrolled. Patients' demographics were recorded as well as transthoracic echocardiography (ECHO), 6MWD, spirometry, arterial blood gas (ABG) values and high resolution chest computed tomography. 6MWT results were compared with other parameters.ResultsThirty four patients with kyphoscoliosis and chronic respiratory insufficiency admitted to our outpatient clinic were included in the study but 25 (17 M) patients underwent 6MWT (8 patients walked with oxygen supplement due to PaO2 < 60 mm Hg). The mean 6MWD was 274.4 ± 76.2 (median 270) m and median 6MWD predicted rate was 43.7% (inter quartile ratio, IQR, 37.6% to 47.7%). Median HMV use was 3 years (IQR 2-4). 6MWD predicted rate, body mass index (BMI), HMV duration were similar in male and female patients. 6MWD correlated well with age, BMI, dyspnea score for baseline 6MWT (r: - 0.59, p < 0.002, r: - 0.58, p < 0.003, r: - 0.55, p < 0.005 respectively) but modestly with forced expiratory volume in one second, pulse rate for baseline 6MWT, pulse saturation rate, fatigue and dyspnea score at end of 6MWT (r: - 0.44, p < 0.048; r: 0.44, p < 0.027; r: - 0.43, p < 0.031; r: - 0.42, p < 0.036; r: - 0.42, p < 0.034 respectively). 6MWD predicted rate was only correlated with dyspnea score at baseline (r: - 0.46, p < 0.022). The systolic pulmonary arterial pressure (PAPs) in 6 (24%) cases was more than 40 mmHg, in whom mean PaO2/FiO2 was 301.4 ± 55.4 compared to 280.9 ± 50.2 in those with normal PAPs (p > 0.40).ConclusionThe 6MWT is an easy way to evaluate physical performance limitation in kyphoscoliosis patients with chronic hypercapnic respiratory failure using home mechanical ventilation. Nearly 275 m was the mean distance walked in the 6MWT, but rather than distance in meters, the 6MWD predicted rate according to gender and body mass index equation might be a better way for deciding about physical performance of these patients. Dyspnea score at baseline before the 6MWT may be the most important point that affects 6MWD in this patient population.

Placebo-Driven Clinical Trials of Transfer Point Glucan #300 in Children With Chronic Respiratory Problems: Iii. Clinical Findings

“…Observed levels were significantly lower than found in literature, most probably as a result of chronic respiratory problems (Karakurt et al, 2010;Li et al, 2005;. The physical conditions of children gradually improved during the stay in sanatorium and at the end of their stay, the 6MWT levels were significantly better.…”

“…Our finding of 6MWT in the glucansupplemented group were better than in the placebo group and correspond well with the improvements in salivary immunity. As the overall regime of children, including physical challenges, organized rest and nutrition, are identical in both groups, the observed changes were not influenced by these outside parameters (Casanova et al, 2011;Karakurt et al, 2010;Lehne et al, 2005). Therefore, we can conclude that 6MWT test represents a solid tool for measurements of the success of complex spa treatment and glucan supplementation (Lehne et al, 2005;Li et al, 2007).…”

“…In both groups there were an extremely high number of participants exposed to passive smoking (52.4% in glucan group, 63.2% in placebo group). All participants absolved at the beginning and at the end 6MWT based on suggested development, including evaluation of additional parameters such frequency before and after physical stress, oxygen saturation, interruption of stress due to the tirednes (Casanova et al, 2011;Karakurt et al, 2010;Lehne et al, 2005;ATSD, 2005). Similarly, evaluation of exhaled nitric oxide was done at the beginning and at the end of the study (Kharitonov et al, 2003;Groneberg-Kloft et al, 2006).…”

Kyphoscoliosis—What Can We Do for Respiration besides NIV?

“…Body mass index (BMI) and age have been negatively correlated with 6MWD, but no correlation has been found with the level of arterial blood gases. Karakurt et al [12] have reported that patients with kyphoscoliosis walked a much shorter distance than they ought to (median 270 m -43.7% of predicted distance) [12]. Oxygen supplementation at the beginning and during the 6MWT did not elongate 6MWD, but long-term therapy with non-invasive ventilation (NIV) was found to have a significant positive effect [4].…”

The 6-Minute Walk Test in Chronic Respiratory Failure: Does Observed or Predicted Walk Distance Better Reflect Patient Functional Status?

“…We have previously shown that by using reference equations (age, sex, and BMI), pulmonary functions in kyphoscoliosis patients with chronic hypercapnic respiratory failure and on home NIV are better correlated with percent-ofpredicted 6MWD than with actual 6MWD. 12 In current clinical practice the distance walked is the only crucial factor for physicians when making clinical judgments on patients with cardiopulmonary diseases. The actual 6MWD uses only the number of meters walked, but the walking distance is dependent on various factors such as age, sex, and BMI.…”