Vasileios Andrianopoulos1, Lowie E G W Vanfleteren2, Inga Jarosch3, Rainer Gloeckl4, Tessa Schneeberger5, Emiel F M Wouters6, Martijn A Spruit7, Klaus Kenn8. 1. Department of Research and Education, CIRO+, Centre of Expertise for Chronic Organ Failure, Horn, The Netherlands; Department of Respiratory Medicine and Pulmonary Rehabilitation, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany. Electronic address: VAndrianopoulos@schoen-kliniken.de. 2. Department of Research and Education, CIRO+, Centre of Expertise for Chronic Organ Failure, Horn, The Netherlands; Department of Respiratory Medicine, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands. Electronic address: lowievanfleteren@ciro-horn.nl. 3. Department of Respiratory Medicine and Pulmonary Rehabilitation, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany. Electronic address: IJarosch@Schoen-Kliniken.de. 4. Department of Respiratory Medicine and Pulmonary Rehabilitation, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany; Department for Prevention, Rehabilitation and Sports Medicine, Klinikum Rechts der Isar, Technische Universität München (TUM), Munich, Germany. Electronic address: RGloeckl@Schoen-Kliniken.de. 5. Department of Respiratory Medicine and Pulmonary Rehabilitation, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany; Department of Pulmonary Rehabilitation, Philipps University Marburg, Marburg, Germany. Electronic address: TSchneeberger@Schoen-Kliniken.de. 6. Department of Research and Education, CIRO+, Centre of Expertise for Chronic Organ Failure, Horn, The Netherlands; Department of Respiratory Medicine, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands. Electronic address: ewouters@ciro-horn.nl. 7. Department of Research and Education, CIRO+, Centre of Expertise for Chronic Organ Failure, Horn, The Netherlands; REVAL - Rehabilitation Research Center, BIOMED - Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Diepenbeek, Belgium. Electronic address: martijnspruit@ciro-horn.nl. 8. Department of Respiratory Medicine and Pulmonary Rehabilitation, Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee, Germany; Department of Pulmonary Rehabilitation, Philipps University Marburg, Marburg, Germany. Electronic address: KKenn@Schoen-Kliniken.de.
Abstract
BACKGROUND: Transcutaneous carbon-dioxide partial-pressure (TCPCO2) can be reliably measured and may be of clinical relevance in COPD. Changes in TCPCO2 and exercise-induced hypercapnia (EIH) during six-minute walk test (6MWT) need further investigation. We aimed (1) to define patterns of TCPCO2 trends during 6MWT and (2) to study determinants of CO2-retention and EIH. METHODS: Sixty-two COPD patients (age: 63±8years, FEV1: 33±10%pred.) were recruited and TCPCO2 was recorded by SenTec digital-monitoring-system during 6MWT. RESULTS: Half of patients (50%) exhibited CO2-retention (TCPCO2[Δ]>4mmHg); 26% preserved and 24% reduced TCPCO2. Nineteen (31%) patients presented EIH (TCPCO2>45mmHg). EIH was associated to higher baseline-PCCO2, worse FEV1, lower inspiratory-pressures, underweight/normal BMI, and pre-walk dyspnea. Stronger determinants of CO2-retention were FEV1 and pre-walk dyspnea, whereas baseline-PCCO2 and pre-walk dyspnea better predict EIH. CONCLUSIONS: PCO2 response to 6MWT is highly heterogeneous; however, very low FEV1 and elevated baseline-PCCO2 together with pre-walk dyspnea increase the risk for CO2-retention and EIH. Overweight-BMI seems to carry a protective effect against EIH in very severe COPD.
BACKGROUND: Transcutaneous carbon-dioxide partial-pressure (TCPCO2) can be reliably measured and may be of clinical relevance in COPD. Changes in TCPCO2 and exercise-induced hypercapnia (EIH) during six-minute walk test (6MWT) need further investigation. We aimed (1) to define patterns of TCPCO2 trends during 6MWT and (2) to study determinants of CO2-retention and EIH. METHODS: Sixty-two COPDpatients (age: 63±8years, FEV1: 33±10%pred.) were recruited and TCPCO2 was recorded by SenTec digital-monitoring-system during 6MWT. RESULTS: Half of patients (50%) exhibited CO2-retention (TCPCO2[Δ]>4mmHg); 26% preserved and 24% reduced TCPCO2. Nineteen (31%) patients presented EIH (TCPCO2>45mmHg). EIH was associated to higher baseline-PCCO2, worse FEV1, lower inspiratory-pressures, underweight/normal BMI, and pre-walk dyspnea. Stronger determinants of CO2-retention were FEV1 and pre-walk dyspnea, whereas baseline-PCCO2 and pre-walk dyspnea better predict EIH. CONCLUSIONS: PCO2 response to 6MWT is highly heterogeneous; however, very low FEV1 and elevated baseline-PCCO2 together with pre-walk dyspnea increase the risk for CO2-retention and EIH. Overweight-BMI seems to carry a protective effect against EIH in very severe COPD.
Authors: Ivan Tomasic; Nikica Tomasic; Roman Trobec; Miroslav Krpan; Tomislav Kelava Journal: Med Biol Eng Comput Date: 2018-03-05 Impact factor: 2.602