Débora Aparecida Oliveira Modena1, Marcos Mello Moreira2, Ilma Aparecida Paschoal3, Mônica Corso Pereira3, Luiz Cláudio Martins3, Everton Cazzo4, Elinton Adami Chaim5. 1. PT, MSc. Doctoral Student, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil. 2. PT, PhD. Professor, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil. 3. MD, PhD. Pneumologist and Professor, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil. 4. MD, PhD. Attending Physician and Assistant Lecturer, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil. 5. MD, PhD. General Surgeon and Professor, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil.
Abstract
BACKGROUND: Excess trunk body fat in obese individuals influences respiratory physiological function. The aims of this study were to compare volumetric capnography findings (VCap) between severely obese patients and normal-weight subjects and to assess whether there is any association between neck circumference (NC), waist-hip ratio (WHR) and VCap among grade III obese individuals. DESIGN AND SETTING: Analytical observational case-matched cross-sectional study, University of Campinas. METHODS: This cross-sectional study compared VCap variables between 60 stage III obese patients and 60 normal-weight individuals. RESULTS: In comparison with the normal-weight group, obese patients presented higher alveolar minute volume (8.92 ± 4.94 versus 6.09 ± 2.2; P = < 0.0001), CO2 production (278 ± 91.0 versus 209 ± 60.23; P < 0.0001), expiratory tidal volume (807 ± 365 versus 624 ± 202; P = 0.005), CO2 production per breath (21.1 ± 9.7 versus 16.7 ± 6.16; P = 0.010) and peak expiratory flow (30.9 ± 11.9 versus 25.5 ± 9.13; P = 0.004). The end-expiratory CO2 (PetCO2) concentration (33.5 ± 4.88 versus 35.9 ± 3.79; P = 0.013) and the phase 3 slope were normalized according to expired tidal volume (0.02 ± 0.05 versus 0.03 ± 0.01; P = 0.049) were lower in the obese group. CONCLUSIONS: The greater the NC was, the larger were the alveolar minute volume, anatomical dead space, CO2 production per minute and per breath and expiratory volume; whereas the smaller were the phase 2 slope (P2Slp), phase 3 slope (P3Slp) and pressure drop in the mouth during inspiration.
BACKGROUND: Excess trunk body fat in obese individuals influences respiratory physiological function. The aims of this study were to compare volumetric capnography findings (VCap) between severely obesepatients and normal-weight subjects and to assess whether there is any association between neck circumference (NC), waist-hip ratio (WHR) and VCap among grade III obese individuals. DESIGN AND SETTING: Analytical observational case-matched cross-sectional study, University of Campinas. METHODS: This cross-sectional study compared VCap variables between 60 stage III obesepatients and 60 normal-weight individuals. RESULTS: In comparison with the normal-weight group, obesepatients presented higher alveolar minute volume (8.92 ± 4.94 versus 6.09 ± 2.2; P = < 0.0001), CO2 production (278 ± 91.0 versus 209 ± 60.23; P < 0.0001), expiratory tidal volume (807 ± 365 versus 624 ± 202; P = 0.005), CO2 production per breath (21.1 ± 9.7 versus 16.7 ± 6.16; P = 0.010) and peak expiratory flow (30.9 ± 11.9 versus 25.5 ± 9.13; P = 0.004). The end-expiratory CO2 (PetCO2) concentration (33.5 ± 4.88 versus 35.9 ± 3.79; P = 0.013) and the phase 3 slope were normalized according to expired tidal volume (0.02 ± 0.05 versus 0.03 ± 0.01; P = 0.049) were lower in the obese group. CONCLUSIONS: The greater the NC was, the larger were the alveolar minute volume, anatomical dead space, CO2 production per minute and per breath and expiratory volume; whereas the smaller were the phase 2 slope (P2Slp), phase 3 slope (P3Slp) and pressure drop in the mouth during inspiration.
Authors: Patricia A Espinoza López; Kelly Jéssica Fernández Landeo; Rodrigo Ricardo Pérez Silva Mercado; Jesús José Quiñones Ardela; Rodrigo M Carrillo-Larco Journal: Wellcome Open Res Date: 2021-01-26