Portable Oxygen Therapy: Is the 6-Minute Walking Test Overestimating the Actual Oxygen Needs?

Daniel Sanchez-Morillo,Blanca Priego-Torres,Maria Morales-Gonzalez,Francisca Montoro-Ballesteros,Alejandro Lara-Doña,Antonio Leon-Jimenez

doi:10.3390/jcm9124007

Abstract

The appropriate titration for the personalized oxygen needs of patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia is a determining factor in the success of long-term oxygen therapy. There are no standardized procedures to assist in determining the patient’s needs during the physical activities of daily life. Despite that effort tests are a wide broad approach, further research concerning the development of protocols to titrate O2 therapy is needed. The main objective of this study was to assess whether the level of oxygen titrated through the 6-minute walking test (6MWT) for patients with COPD and exertional hypoxemia is adequate to meet the patients’ demand during their activities of daily living. Physiological and subjective variables were estimated for a study population during two walking tests: a 6MWT and a 20-minute walking circuit (20MWC), designed ad-hoc to reproduce daily physical activities more truthfully. The results indicate that in a significant proportion of patients, the 6MWT might not accurately predict their oxygen needs at a domiciliary environment. Therefore, the titration of the portable O2 therapy could not be optimal in these cases, with the detrimental impact on the patient’s health (hyperoxia episodes), the autonomy of the oxygen device, and the decrease of time out of the home.

Highlights

Since the studies carried out in the 1980s in which both the Nocturnal Oxygen Therapy Trial [1] and the British Medical Research Council study [2] demonstrated the benefits of oxygen therapy on the survival of patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia, the use of this therapy has not ceased to grow, multiplying its incidence by more than three times in some countries [3] and with an estimated global cost of 18.2 billion by 2024 [4].In the general context of COPD, long-term supplemental oxygen therapy (LTOT) is relevant for a variable percentage of patients
Clinical guidelines state that LTOT is a proven treatment associated with a lower mortality rate for paTtiaebnltes3w
0.0092 therapry=u0s.2in2 g[−p0.o29r–ta0.b6l3e], cpo=n0c.e40n0t6rators to faci∆liLtaetgeFaatmigbueulati0o.4n±is0.c9o[−m0.m1–o0.n9]ly de1.s2ig±n1e.8d[0a.3n–d2.2c]ustom0.1iz25e0d throurg=h0t.4h4e[−60M.05W–0T.7.8]E, vp i=d0e.n07c3e9 from studies with COPD patients indicates that 6-minute walking test (6MWT) is an effective method of detecting exercise-induced

Summary

Introduction

Since the studies carried out in the 1980s in which both the Nocturnal Oxygen Therapy Trial [1] and the British Medical Research Council study [2] demonstrated the benefits of oxygen therapy on the survival of patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia, the use of this therapy has not ceased to grow, multiplying its incidence by more than three times in some countries [3] and with an estimated global cost of 18.2 billion by 2024 [4].In the general context of COPD, long-term supplemental oxygen therapy (LTOT) is relevant for a variable percentage of patients. It has been reported that 47% of patients with COPD experience episodes of desaturation during exercise that manifest themselves with SpO2 values

Objectives

Methods

Conclusion