BACKGROUND: At Bogota's altitude (2640 m), the lower barometric pressure (560 mmHg) causes severe hypoxemia in COPD patients, limiting their exercise capacity. The aim was to compare the effects of breathing oxygen on exercise tolerance. METHODS: In a blind, crossover clinical study, 29 COPD patients (FEV1 42.9 ± 11.9%) breathed room air (RA) or oxygen (FIO2 28% and 35%) during three treadmill exercise tests at 70% of their maximal capacity in a randomized order. Endurance time (ET), inspiratory capacity (IC), arterial blood gases and lactate were compared. RESULTS: At the end of the exercise breathing RA, the ET was 9.7 ± 4.2 min, the PaO2 46.5 ± 8.2 mmHg, the lactate increased and the IC decreased. The oxygen significantly increased the ET (p < 0.001), without differences between 28% (16.4 ± 6.8 min) and 35% (17.6 ± 7.0 min) (p = 0.22). Breathing oxygen, there was an increase in the PaO2 and SaO2, higher with FIO2 35%, and a decrease in the lactate level. At "isotime" (ET at RA), with oxygen, the SpO2, the oxygen pulse and the IC were higher and the heart rate lower than breathing RA (p < 0.05). CONCLUSION: Oxygen administration for COPD patients in Bogotá significantly increased ET by decreased respiratory load, improved cardiovascular performance and oxygen transport. The higher increases of the PaO2 and SaO2 with 35% FIO2 did not represent a significant advantage in the ET. This finding has important logistic and economic implications for oxygen use in rehabilitation programs of COPD patients at the altitude of Bogotá and similar altitudes.
RCT Entities:
BACKGROUND: At Bogota's altitude (2640 m), the lower barometric pressure (560 mmHg) causes severe hypoxemia in COPDpatients, limiting their exercise capacity. The aim was to compare the effects of breathing oxygen on exercise tolerance. METHODS: In a blind, crossover clinical study, 29 COPDpatients (FEV1 42.9 ± 11.9%) breathed room air (RA) or oxygen (FIO2 28% and 35%) during three treadmill exercise tests at 70% of their maximal capacity in a randomized order. Endurance time (ET), inspiratory capacity (IC), arterial blood gases and lactate were compared. RESULTS: At the end of the exercise breathing RA, the ET was 9.7 ± 4.2 min, the PaO2 46.5 ± 8.2 mmHg, the lactate increased and the IC decreased. The oxygen significantly increased the ET (p < 0.001), without differences between 28% (16.4 ± 6.8 min) and 35% (17.6 ± 7.0 min) (p = 0.22). Breathing oxygen, there was an increase in the PaO2 and SaO2, higher with FIO2 35%, and a decrease in the lactate level. At "isotime" (ET at RA), with oxygen, the SpO2, the oxygen pulse and the IC were higher and the heart rate lower than breathing RA (p < 0.05). CONCLUSION:Oxygen administration for COPDpatients in Bogotá significantly increased ET by decreased respiratory load, improved cardiovascular performance and oxygen transport. The higher increases of the PaO2 and SaO2 with 35% FIO2 did not represent a significant advantage in the ET. This finding has important logistic and economic implications for oxygen use in rehabilitation programs of COPDpatients at the altitude of Bogotá and similar altitudes.
Authors: Lu Tan; Tsogyal D Latshang; Sayaka S Aeschbacher; Fabienne Huber; Deborah Flueck; Mona Lichtblau; Stefanie Ulrich; Elisabeth D Hasler; Philipp M Scheiwiller; Silvia Ulrich; Konrad E Bloch; Michael Furian Journal: JAMA Netw Open Date: 2020-06-01
Authors: Sophia Gutweniger; Tsogyal D Latshang; Sayaka S Aeschbacher; Fabienne Huber; Deborah Flueck; Mona Lichtblau; Stefanie Ulrich; Elisabeth D Hasler; Philipp M Scheiwiller; Silvia Ulrich; Konrad E Bloch; Michael Furian Journal: Sci Rep Date: 2021-10-13 Impact factor: 4.379
Authors: Mauricio Gonzalez-Garcia; Emily Rincon-Alvarez; Maria Laura Alberti; Mauricio Duran; Fabian Caro; Maria Del Carmen Venero; Yuri Edison Liberato; Ivette Buendia-Roldan Journal: Front Med (Lausanne) Date: 2021-06-17