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Published on: April 7, 2021
Immediate effects of manual hyperinflation on cardiorespiratory function and sputum clearance in mechanically
Tawatchai Luadsri1, Jaturon Boonpitak2, Kultida Pongdech-Udom3
1Exercise and Rehabilitation Sciences Research Unit, Department of Physical Therapy, Faculty of Allied Health Sciences, Naresuan University, Pitsanulok, Thailand.
Insights
Manual hyperinflation (MHI) improves lung function and secretion clearance in pediatric patients on mechanical ventilation. This technique enhances tidal volume and lung compliance without adverse hemodynamic effects, aiding secretion mass removal.
Area of Science:
- Pediatric Critical Care Medicine
- Respiratory Therapy
- Pulmonary Physiology
Background:
- Lower respiratory tract infections are a leading cause of mortality in children in developing nations, often requiring critical care.
- Manual hyperinflation (MHI) is a common physical therapy technique for secretion clearance in critical care, but its pediatric efficacy is unproven.
Purpose of the Study:
- To evaluate the impact of MHI on secretion mass clearance in mechanically ventilated pediatric patients.
- To assess the cardiorespiratory effects of MHI in this patient population.
Main Methods:
- A randomized crossover study involving 12 intubated, mechanically ventilated pediatric patients.
- Patients received MHI with suction and suction alone in a randomized order, with a 4-hour washout period.
Main Results:
- MHI significantly increased tidal volume and static lung compliance compared to baseline.
- MHI with suction resulted in greater secretion mass clearance than suction alone.
- No significant differences were observed in peak inspiratory pressure, airway pressures, respiratory rate, heart rate, blood pressure, or oxygen saturation.
Conclusions:
- Manual hyperinflation is effective in improving lung mechanics (tidal volume, static lung compliance) and secretion clearance in pediatric patients on mechanical ventilation.
- MHI, when combined with suction, enhances secretion mass removal.
- The MHI technique does not appear to cause adverse hemodynamic effects in this patient group.
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 [ ; 1.2 mL/kg (95% CI, 0.8-1.5)] and static lung compliance [ ; 3.7 mL/cmH2O (95% CI, 2.6-4.8)] immediately post-intervention compared with the baseline ( ). Moreover, the MHI with suction induced higher [1.4 mL/kg (95% CI, 0.8-2.1)] and [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 ( ). 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 ( ) between interventions.
Conclusions:
MHI can improve , and secretion mass without inducing adverse hemodynamic effects upon the pediatric patients requiring mechanical ventilation.
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