Short-term effects on outcomes related to the mechanism of intervention and physiological outcomes but insufficient evidence of clinical benefits for breathing control: a systematic review.
OBJECTIVE
What is the volume, quality, consistency, and generalisability of the evidence for breathing control? What is the effect on outcomes related to the target and mechanism of breathing control, as well as physiological and clinical outcomes?


METHODS
Systematic review with meta-analysis.


METHODS
People with chronic respiratory disease, post-surgical, or asymptomatic individuals.


METHODS
Breathing control (relaxed basal, diaphragmatic, or abdominal breathing) as the sole intervention.


METHODS
All outcome measures providing continuous data.


RESULTS
Twenty studies were included within the meta-analysis. A beneficial effect was found for abdominal movement (SMD 1.36, 95% CI 0.42 to 2.31), diaphragm excursion (SMD 1.39, 95% CI 1.00 to 1.77), respiratory rate (SMD -0.84, 95% CI -1.09 to -0.60), tidal volume (SMD 0.98, 95% CI 0.71 to 1.25), arterial oxygen saturation (SMD 0.63, 95% CI 0.25 to 1.02) and percutaneous oxygen (SMD 1.48, 95% CI 0.85 to 2.11). Breathing control had a detrimental effect on the work of breathing (SMD 1.06, 95% CI 0.52 to 1.60) and dyspnoea (SMD 1.47, 95% CI 0.88 to 2.05).


CONCLUSIONS
When used as a sole intervention, there was a beneficial effect on outcomes related to the mechanism of breathing control as well as on short-term physiological outcomes. In people with severe respiratory disease, breathing control resulted in a detrimental effect on dyspnoea and work of breathing. There was no clear evidence of an effect on ventilation or long-term physiological outcomes related to gas exchange or the energy cost of breathing. Overall, evidence was satisfactory with studies demonstrating poor consistency, good generalisability, and satisfactory volume and quality.
Lewis
Lucy K
LK
School of Health Sciences (Physiotherapy), University of South Australia, Adelaide SA 5000, Australia. lucy.lewis@unisa.edu.au
Williams
Marie T
MT
Olds
Tim
T
D001945:Breathing Exercises; D006801:Humans; D008171:Lung Diseases / Q000503:physiopathology / Q000534:rehabilitation* / Q000628:therapy; D026741:Physical Therapy Modalities; D011659:Pulmonary Gas Exchange / Q000502:physiology; D015656:Respiratory Mechanics / Q000502:physiology; D016896:Treatment Outcome