OS VALORES NORMATIVOS DE REFERÊNCIA PARA EFICIÊNCIA VENTILATÓRIA NO BRASIL E NO MUNDO: UM ESTUDO IN-SILICO

Abstract

This study examines the VE-VCO2 inclinação, a critical measure in CPET that verifies the amount of CO2 that is removed during exercise. This imbalance often results in dyspnea, a marker for negative patient outcomes. Despite its importance, the comparability of VE-VCO2 inclinaçãos between different ergometers and genders in various countries has been little studied. Our research analyzed several VE-VCO2 predictive equations based on gender, age and ergometer type, focusing on them as the only independent variables, with the aim of developing a reference model for ventilatory efficiency, identifying discrepancies and similarities for global application. The methodology involved an IN-SILICO study. After identifying the main VE-VCO2 assessment equations, we included only those that included gender and age for the computer simulations. We excluded equations with quadratic formulas or additional variables. These simulations generated 5,000 iterations for n=150, covering ages from 20 to 80. This large sample size was aimed at statistically robust data to propose new guidelines for assessing ventilatory efficiency. The main findings showed moderate to high disagreement between age-based VE-VCO2 predictive equations in different populations. When comparing ergometers, men showed lower rates of disagreement than women. Our study found high agreement in men, but not in women, suggesting more specific ergometer-dependent differences in women. This may be due to different breathing strategies and ventilatory restrictions between the sexes. One limitation is the small number of age-based equations for comparison. However, our statistical approach was adequate for meaningful comparisons. In conclusion, predictive equations for VE-VCO2 inclinaçãos are highly discordant on a crosscultural basis for both ergometers. A global initiative to develop universal equations is needed due to the importance of this index in the clinical setting, especially for assessing dyspnea and predicting clinical and surgical morbidity/mortality.