Clinical trial NCT04955561: CO2-Patterns During Hyperoxia and Physical Exercise in COPD
Official title: CO2-Patterns During Hyperoxia and Physical Exercise in People With Severe COPD - a Randomized, Double-blind Cross Over Trial
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: COPD
Keywords: CO2
oxygen
walking exercise
Lead sponsor: Schön Klinik Berchtesgadener Land
Sponsor class: OTHER
First posted: 2021-07-09
Enrollment: 55
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: The aim of the study is to investigate a possible correlation between the change in PCO2 during a hyperoxia-test and the change in PCO2 during walking in people with COPD

Detailed description: Rationale:

Carbon dioxide partial pressure (PCO2) varies significantly in patients with advanced chronic obstructive pulmonary disease (COPD). Data from the Swedish LTOT Registry showed that PCO2 is an independent predictor for mortality and that there is a U-shaped relationship. Patients with advanced COPD who are still normocapnic at rest may still develop a clinically relevant, exercise-induced carbon dioxide (CO2) retention during exercise/ activity. It is also known that altered breathing patterns at night in COPD patients can lead to nocturnal hypercapnia, especially during REM sleep. The course of PCO2 cannot be reliably predicted by lung function parameters or resting blood gas analysis. Since exercise tests with blood gas control or nightly PCO2 monitoring are rarely performed in clinical routine, exercise induced CO2 retention often remains undetected. In the literature, there is little information on PCO2 behaviour under everyday conditions (with or without LTOT) such as rest, physical exertion and nightly sleep. Therefore, predictors that could describe the PCO2 patterns are missing. However, one former study by O'Donnel from 2002 showed that the change in CO2 under hyperoxia conditions could provide predictive information for the change in CO2 with exercise.

Objective:

Primary aim of this study is to investigate whether the change of PCO2 during a hyperoxia-test (10l/min O2 at rest) correlates with the change of PCO2 during walking exercise with either a: l/min O2 as prescribed; b: medical air; c: 10l/min O2.

Design:

This study is a randomized, controlled cross-over trial. Following an initial maximal incremental shuttle walk test (ISWT), the participant will perform 3 endurance shuttle walk tests (ESWT) at 85% of the maximum ISWT pace on three consecutive days (24h break between ESWTs). In a randomized order, participants will perform one ESWTs with O2-flow as prescribed (e.g. study day 1), one with medical air (same flow rate as prescribed oxygen) (e.g. study day 2) and one with 10l/min O2 (e.g. study day 3). An additional hyperoxia test (10l/min O2 for ten minutes; at resting condition) will be perfomed on each day prior to performing an ESWT.

Eligibility criteria: Inclusion Criteria:

* COPD III/ IV
* 35mmHg \< PCO2 \<= 55mmHg (under resting conditions, breathing room air)
* Hypoxemia (PaO2\<60mmHg) under room air conditions (rest or during exercise) or SpO2 \<88% during exercise
* established oxygen therapy or given indication for oxygen therapy
* written informed consent

Exclusion Criteria:

* acute exacerbation of COPD
* exercise limiting cardiac or orthopedic comorbidites
* PaO2 \<50mmHg at rest, breathing room air

Primary outcomes:
measure: Change in PCO2 during hyperoxia at rest
timeFrame: Change from baseline to after 10 minutes breathing 10L/min oxygen
measure: Change in PCO2 from rest to end exercise (endurance shuttle walk test)
timeFrame: Change from baseline to the end of the ESWT, up to 20 minutes
Secondary outcomes:
measure: Transcutaneous partial pressure of CO2 (TcPCO2) during hyperoxia test
timeFrame: Continuously from baseline to 10 minutes breathing 10L/min oxygen
measure: Transcutaneous partial pressure of CO2 (TcPCO2) during endurance shuttle walk test
timeFrame: Continuously during ESWT, up to 20 minutes
measure: Breathing frequency during hyperoxia test
timeFrame: Continuously from baseline to 10 minutes breathing 10L/min oxygen
measure: Breathing frequency during endurance shuttle walk test
timeFrame: Continuously during ESWT, up to 20 minutes
measure: Heart rate during endurance shuttle walk test
timeFrame: Continuously during ESWT, up to 20 minutes
measure: Heart rate during hyperoxia test
timeFrame: Continuously from baseline to 10 minutes breathing 10L/min oxygen
measure: Change of capillary partial pressure of O2 (pO2) during endurance shuttle walk test
timeFrame: Change from baseline to the end of the ESWT, up to 20 minutes
measure: Change of inspiratory capacity during endurance shuttle walk test
timeFrame: Change from baseline to the end of the ESWT, up to 20 minutes
Other outcomes:
Locations:
city: Schönau am Königssee
country: Germany
facility: Klinikum Berchtesgadener Land, Schön Kliniken
Study officials:
References: