Immediate Respiratory Warm-Up Effect on Dynamic Inspiratory Muscle Strength in Cardiac Surgery Candidates

Bahareh  Mehregan Far; Sedigheh Sadat  Naimi; Mohsen  Abedi; Seyed Ahmad  Raeissadat; Mahmood Beheshti  Monfared; Alireza Akbarzadeh  Baghban

doi:10.18502/jmr.v19i1.17514

Bahareh Mehregan Far Student Research Committee, Department of Physiotherapy, School of Rehabilitation Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Sedigheh Sadat Naimi Department of Physiotherapy, Physiotherapy Research Center, School of Rehabilitation Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Mohsen Abedi Department of Physiotherapy, Physiotherapy Research Center, School of Rehabilitation Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Seyed Ahmad Raeissadat Department of Physical Medicine and Rehabilitation, Clinical Development Research Center, Shahid Modarres Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Mahmood Beheshti Monfared Department of Cardiovascular Surgery, Clinical Development Research Center, Shahid Modarres Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Alireza Akbarzadeh Baghban Department of Biostatistics, Proteomics Research Center, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

DOI: https://doi.org/10.18502/jmr.v19i1.17514

Keywords: Dynamic respiratory pressure; Warm-up; Cardiac disease

Abstract

Introduction:The strength of inspiratory muscles is one of the essential factors in preventing postoperative pulmonary complications (POPC). One of the new tools to safely measure the strength of the inspiratory muscles in heart patients dynamically and without breath holding is the strength-index (S-index). This study aims to evaluate the immediate effects of a respiratory warm-up (RWU) session on the S-index and other lung parameters in cardiac surgery candidates, a subject with limited existing research.

Materials and Methods: This study was conducted as a randomized controlled trial. Forty participants scheduled for heart surgeries were randomly assigned to either the study (RWU between two tests) or control (without RWU) groups. RWU consists of threshold loading inspiratory muscle training (TL-IMT) exercises at 30% of the S-index with 30 breathing cycles. Respiratory tests, including S-index, peak inspiratory flow (PIF) and vital capacity (VC), were assessed twice using an electronic respiratory device.

Results: Covariance analysis showed no significant difference in the average and best values of the S-index, PIF or VC indices at the second tests, between two groups (P>0.05), or in the independent t test and Mann-Whitney U test for the “rate of changes,” between two tests (P>0.05). Finally, intra- group changes, assessed with paired sample t test between two tests, were mostly non-significant for these indices (P>0.05), except for the best VC in the study group (P=0.03).

Conclusion: The study results suggest that a RWU session does not significantly impact cardiac surgery candidates’ S-index or other respiratory parameters. Thus, incorporating RWU before S-index testing may not be necessary.