The purpose of this research study is to evaluate effects of respiratory strengthening exercises on breathing function, in people who have orthopedic surgery. It is known that breathing function decreases for a few days after surgery. in In this study, we want to see if exercising before surgery strengthens the breathing muscles and improves recovery after surgery.

Preoperative inspiratory muscle training (IMT) has been shown to reduce post operative complications (PPC's) following prolonged cardiac surgeries, but its potential benefits have not been investigated in shorter surgeries with expected brief post-operative hospitalizations. We intend to address this unmet need by investigating preoperative IMT, an evidence-based rehab strategy to optimize lung function, prior to total joint arthroplasty surgery. The fundamental hypothesis guiding this proposal is that preoperative IMT will attenuate post-operative declines in breathing function and offset PPCs. To test this hypothesis, we will conduct a single center, randomized, prospective pilot study. Adults scheduled for total joint arthroplasty or lower extremity orthopedic surgery will be randomized to either complete daily IMT in advance of surgery (dIMT), a single acute IMT session immediately before surgery (aIMT), or usual surgical standard of care (SOC). Inspiratory muscle strength and pulmonary function will be evaluated upon enrollment ~4 weeks in advance of surgery and in pre-operative holding, and post-operative declines will be investigated through the first 24 hours (Aim 1). Further, we will investigate the effect of training assignment on post-operative clinical outcomes (Aim 2).

Inclusion Criteria:

• 18 or older
• History of current or previous tobacco use (including vaping containing nicotine products)
• One or more risk factors for post operative pulmonary complications including history of current or previous tobacco use, a clinically diagnosed lung disease, shortness of breath with minimal exertion, FEV1 or FVC less than 80% than predicted or respiratory muscles strength below lower limit of normal for age and sex.
• History of smoking related lung disease
• Projected surgical time > 30 minutes
• Ability to follow instructions to complete IMT exercises
• Ability to communicate adverse effects such as pain or fatigue or the need for assistance

Exclusion Criteria:

• American Society of Anesthesiologists physical status classification of 4 or greater .
• Recent history of acute pneumonia or lower respiratory infection in the previous two weeks requiring acute corticosteroid or antibiotic medication,
• Preoperative dependence on continuous supplemental oxygen dependence.
• Preoperative dependence on positive pressure breathing support while awake and upright (night time CPAP permitted),
• Diagnosis of a neurologic condition (i.e. MS, ALS, Parkinson's, stroke),
• Participating in a pulmonary rehabilitation program
• Severe obstructive pulmonary disease (Classification of Global Initiative for Chronic Obstructive Lung Disease (GOLD) 3 or higher, indicating FEV1<50% predicted.
• Patients with an infectious disease requiring isolation (i.e. COVID-19).