Immediate effects of manual hyperinflation on cardiorespiratory function and sputum clearance in mechanically ventilated pediatric patients: A randomized crossover trial.

Background: In developing countries, lower respiratory tract infection is a major cause of death in children, with severely ill patients being admitted to the critical-care unit. While physical therapists commonly use the manual hyperinflation (MHI) technique for secretion mass clearance in critical-care patients, its efficacy has not been determined in pediatric patients.

Objective: This study investigated the effects of MHI on secretion mass clearance and cardiorespiratory responses in pediatric patients undergoing mechanical ventilation.

Methods: A total of 12 intubated and mechanically ventilated pediatric patients were included in this study. At the same time of the day, the patients received two randomly ordered physical therapy treatments (MHI with suction and suction alone) from a trained physical therapist, with a washout period of 4 h provided between interventions.

Results: The MHI treatment increased the tidal volume [ $V_t$ ; 1.2 mL/kg (95% CI, 0.8-1.5)] and static lung compliance [ $C_{\text{stat}}$ ; 3.7 mL/cmH₂O (95% CI, 2.6-4.8)] immediately post-intervention compared with the baseline ( $p<0.05$ ). Moreover, the MHI with suction induced higher $V_t$ [1.4 mL/kg (95% CI, 0.8-2.1)] and $C_{\text{stat}}$ [3.4 mL/cmH₂O (95% CI, 2.1-4.7)] compared with the suction-alone intervention. In addition, the secretion mass [0.7 g (95% CI, 0.6-0.8)] was greater in MHI with suction compared with suction alone ( $p<0.05$ ). However, there was no difference in peak inspiratory pressure, mean airway pressure, respiratory rate, heart rate, blood pressure, mean arterial blood pressure or oxygen saturation ( $p>0.05$ ) between interventions.

Conclusions: MHI can improve $V_t$ , $C_{\text{stat}}$ and secretion mass without inducing adverse hemodynamic effects upon the pediatric patients requiring mechanical ventilation.