Respiratory Muscle Training

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Table 8: Effect of Respiratory Muscle Training on Pulmonary Function during Acute SCI

After patients have been intubated for a sufficient time during the earliest phase of SCI treatment, a decision must be made as to whether patients will 1) remain on long-term mechanical ventilation through the endotracheal tube, 2) receive a tracheostomy for long-term ventilation or to assist in weaning, or 3) will be extubated and breathing independently. Traditionally, immediate extubation has been viewed as risky and often leads to pulmonary infections or the need for urgent reintubation. Alternatively, long-term ventilation through an endotracheal tube prolongs the weaning process and the duration of hospital stay. The routine practice has been to receive a tracheostomy to initiate weaning and accelerate discharge from the hospital and not be as abrupt as extubation (Berlly & Shem, 2007). However, in patients who tolerate independent breathing and are weaned successfully off the ventilator, respiratory muscle training or acute physiotherapy can be initiated. Acute physiotherapy is an emerging non-invasive option to help patients resume normal pulmonary functioning and timely discharge. Early prophylactic treatment in the form of physiotherapy has been shown to improve diaphragm function and reduce secretions in patients with acute SCI (McMichan et al. 1980). Assisted coughing, intermittent positive pressure breathing, and regular changes in body positioning are some of the techniques used to help keep patients’ airways clear and breathing independently (Berney et al. 2002). In addition, breathing exercises and diaphragm strengthening can also improve lung functioning and assist in weaning from mechanical ventilation. Resistive inspiratory muscle training (RIMT) and abdominal weights training (Gross et al. 1980; Lin et al. 1999) as well as cough training combined with functional electrical stimulation (McBain et al. 2013) are techniques that have been implemented for physiotherapy in chronic SCI patients. RIMT (Derrickson et al. 1992; Postma et al. 2014), expiratory resistive muscle training (Roth et al. 2010) and abdominal weights training (Derrickson et al. 1992) have been studied in the acute SCI population and are reviewed below.


Three RCTs have examined the effectiveness of physiotherapy techniques on the pulmonary function of patients with SCI. Postma et al. (2014) investigated the effect of RIMT in individuals with SCI during inpatient rehabilitation. This technique was found to have a positive short-term effect on inspiratory muscle function 1 week following the intervention period; however, this effect was no longer significant 8 weeks post muscle training. Two types of breathing exercise programs have been shown by one small RCT (Derrickson et al. 1992) to be effective at improving pulmonary function in patients with acute tetraplegia. Abdominal weights training and RIMT both appeared to be similar in efficacy and resulted in within-group improvements for all five (RIMT group) and four of five (abdominal weights training group) pulmonary function measures used in the study. Finally, Roth et al. (2010) assessed the effectiveness of expiratory muscle training compared to sham training in patients with SCI at an acute inpatient rehabilitation hospital. Multivariate analysis did not reveal any significant between-group differences for any pulmonary function tests conducted after the 6-week training period. A moderate sized case control study also found positive results with both inspiratory and combination in- and expiratory muscle training regardless of AIS score (Raab et al., 2018). It was found that measures of inspiratory and expiratory pressure significantly increased, as well as forced vital capacity regardless of muscle training group (Raab et al., 2018). Muscle training appears to be effective for improving respiratory parameters in acute SCI patients.

A case control study (Berney et al. 2002) has shown that extubation along with initiation of intensive physiotherapy can improve lung function, reduce the rate of pulmonary complications and decrease the length of stay in intensive care for patients with acute tetraplegia. It should be noted that both patients who have been extubated or who have had a tracheostomy are able to receive physiotherapy, as long as treatment occurs once the patient is in stable condition.

Physiotherapy treatments during acute SCI would be useful for stable patients and in hospitals that have the resources for on-call physiotherapists. Prospective large-scale RCTs should be conducted to confirm these preliminary findings that physiotherapy is an effective adjuvant to improve acute pulmonary functioning.


There is level 1b evidence (from two RCTs; Postma et al., 2014; Derrickson et al., 1992, and one case control study; Raab et al., 2018)) in support of inspiratory muscle training as an effective means to improve respiratory muscle function compared to usual care in acute SCI patients regardless of AIS status.

There is level 3 evidence (from one case control; Berney et al. 2002) that extubation and intensive physiotherapy reduces length of stay in intensive care in acute SCI patients.

  • Inspiratory and expiratory muscle training may improve respiratory muscle function during the acute phase post SCI. Length of stay in intensive care may be reduced by extubation in combination with intensive physiotherapy.