Relationship between inspiratory muscle strength and cough capacity in cervical spinal cord injured patients

Abstract

Study design: Prospective single centre study. Objectives: Pulmonary rehabilitation focuses on improving the expiratory muscle function in order to increase the reduced cough capacity in patients with cervical spinal cord injuries (SCI). However, an improvement in the inspiratory function is also important for coughing effectively. Therefore, this study was to examine the significance of the inspiratory muscle strength on the cough capacity in the patients with a cervical SCI. Setting: SCI unit, Yonsei Rehabilitation Hospital, Seoul, Korea. Methods: The vital capacity (VC), maximum inspiratory pressure (MIP), and maximum expiratory pressure (MEP) were measured. Moreover, the unassisted peak cough flow (PCF) and assisted PCF under three conditions were evaluated. Results: All three assisted cough methods showed a significantly higher value than the unassisted method (Po0.001). The VC correlated with the voluntary cough capacity and the MIP (R ¼ 0.749) correlated more significantly with the VC than the MEP (R ¼ 0.438) (Po0.01). The MIP showed a higher correlation with both the unassisted PCF and all three assisted PCFs than the MEP (Po0.001). Conclusions: The management of the inspiratory muscle strength should be considered in the pulmonary rehabilitation at cervical SCI patients.

A systematic review and meta-analysis of the effects of respiratory muscle training on pulmonary function in tetraplegia

“…The improvements in MIP, MEP, MVV, VC and IC following RMT that were revealed by the meta-analyses allow us to speculate around causation and mechanisms. The MIP and IC have been directly correlated in previous cross-sectional cohorts 27 and the increases observed in this paper are likely to be directly associated with increased strength in the same muscles. Increases in both MIP and IC would likely also result in a larger measured VC despite no change in 'expiratory' volumes such as the RV.…”

“…A higher IC would result in the MEP being measured at a higher absolute lung volume after RMT, and as such lung elastic recoil would contribute to the observed value to a larger degree. 27 Further, the absence of any demonstrable increase in 'expiratory' measures (PEFR, FEV 1 or ERV) despite the observed increase in MEP may suggest that the elastic recoil effect could have predominated. Most participants in these studies had tetraplegia and thus absent or diminished abdominal and other active expiratory muscle function that could have been trained by RMT.…”

Mechanical Insufflation-Exsufflation Device Prescription for Outpatients With Tetraplegia

“…We consider this to be unlikely for most of these patients, because peak cough flows are typically low for patients with these SCI neurologic impairment classifications (24) and also because the patients were experiencing a mean of more than 0.3 respiratory hospitalizations annually. However, patients did not undergo measurement of unassisted peak cough flow to confirm that their cough was inadequate before MIE prescription.…”

“…However, patients did not undergo measurement of unassisted peak cough flow to confirm that their cough was inadequate before MIE prescription. In addition, some patients may have been able to achieve an adequate assisted cough using air stacking followed by abdominal thrust (24).…”

Use of air stacking and abdominal compression for cough assistance in people with complete tetraplegia

“…Kang et al 17 evaluated the relationship between the ability to cough and inspiratory muscle strength. A secondary objective was obtaining PCF difference between assisted and Use of AS and AC for cough assistance in people with complete tetraplegia R Torres-Castro et al unassisted cough maneuvers.…”