Beyond the Acute Phase: Understanding Relationships Among Cardiorespiratory Response to Exercises, Physical Activity Levels, and Quality of Life in Children After Burn Injuries

The long-term cardiorespiratory function in burn-injured children can be jeopardized due to complications brought on by the injury. This study sought to assess the cardiorespiratory responses to maximal exercise in children who sustained a burn injury and explore the relationships among cardiorespiratory response, physical activity levels (PALs), and health-related quality of life (HRQL). Forty-five burn-injured children (age: 13.89 ± 2.43 years; duration since burn injury: 3.13 ± 0.93 years) and 52 age- and gender-matched healthy children (14.15 ± 2.27 years) participated in this study. Both cohorts were evaluated for the maximal exercise capacity (defined by peak oxygen uptake [VO2peak], maximum heart rate [HRmax], minute ventilation [VE], ventilatory equivalent [VEq], respiratory rate [RR], and respiratory exchange ratio [RER]), PALs, and HRQL. The burn-injured children had significantly lower VO2peak (P =. 0001) and VE (P =. 003) and higher VEq (P <. 0001) and RR (P =. 007) than their healthy controls, indicating less-efficient cardiorespiratory capacity. However, the HRmax (P =. 092) and RER (P =. 251) were similar. The burn-injured children reported significantly lower PALs (P =. 014) and HRQL (P <. 0001). The PALs (r [95% CI] =. 411 [0.132-0.624]; P =. 005) and HRQL (r [95% CI] =. 536 [0.284-0.712]; P =. 0001) were significantly correlated with the cardiorespiratory capacity represented by VO2peak in burn-injured group. The variations in VO2peak explained ~17% and 28.7% of the variations in PALs and HRQL, respectively. In conclusion, the cardiorespiratory efficiency of the burn-injured children may remain limited, even up to a few years following the injury. The limited cardiorespiratory capacity accounts in part for the reduced PALs and HRQL.