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Updated: Sep 18, 2025

Effects of Surgical Masks on Cardiopulmonary Function in Healthy Subjects
Published on: February 12, 2021
Inspiratory Muscle Training Improved Cardiorespiratory Performance in Patients Undergoing Open Heart Surgery: A
Chitima Kulchanarat1, Suphannee Choeirod1, Supattra Thadatheerapat1
1Department of Physical Therapy, Thammasat University Hospital, Pathum Thani 12120, Thailand.
Aim:
This study aimed to evaluate the effects of inspiratory muscle training on inspiratory muscle strength and cardiorespiratory performance in patients undergoing open heart surgery.
Method:
This study was conducted as a randomized controlled trial with two groups. Fifty-eight patients who underwent open heart surgery were randomly assigned to either the intervention group or the control group 29 in the control group and 29 in the intervention group. Patients in the intervention group participated in a physical therapy program combined with inspiratory muscle training using the Thammasat University (TU) Breath Trainer. Patients in the control group received only the standard physical therapy program. The maximum inspiratory pressure, maximum expiratory pressure and 6 min walk test distance were assessed both before surgery and prior to hospital discharge.
Results:
The intervention group had a significant increase in maximum inspiratory pressure (p < 0.001), maximum expiratory pressure (p < 0.001) and 6 min walk test distance (p = 0.013). The control group had a significant decrease in maximum inspiratory pressure (p < 0.001), maximum expiratory pressure (p = 0.002) and 6 min walk test distance (p < 0.001).
Conclusions:
Inspiratory muscle training can be performed using maximum pressure resistors, such as the TU-Breath Trainer device. This training has been shown to effectively improve inspiratory muscle strength and cardiorespiratory performance in patients undergoing open heart surgery, as well as reduce pulmonary complications and shorten the length of hospital stay.
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