Pulmonary Function After Hyperbaric Oxygen Therapy

Study Overview
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Brief Summary
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Patients receiving hyperbaric oxygen therapy (HBOT) for any indication at the Hyperbaric Medicine Unit (University Health Network, Toronto, ON, Canada) from 2016-2021 were recruited to this prospective cohort study. While receiving HBOT (at 2.0-2.4 ATA, with 1-3 air breaks, with specific treatment details determined on a case-by-case basis and directed by the clinical team), enrolled patients underwent pulmonary function testing prior to HBOT treatment and serially after each 20 completed treatment cycles.

Detailed Description
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Patients receiving hyperbaric oxygen therapy (HBOT) at the Hyperbaric Medicine Unit (University Health Network, Toronto, ON, Canada) from 2016-2021 were recruited with informed consent to this prospective cohort study. All included patients underwent HBOT in one of three monoplace chambers (Sechrist 3600H and Sechrist 4100H, Sechrist Industries Inc., Anaheim, CA, USA; PAH-S1-3200, Pan-America Hyperbarics Inc., Plano, TX, USA) or via a plastic hood in a multiplace chamber (Hyperbaric System, Fink Engineering PTY-LTD, Warana, Australia). HBOT was performed with 100% oxygen at 2.0-2.4 ATA, with 1-3 air breaks, typically at 5 sessions per week, with limited variation depending on the treatment indication and patient/clinician decision. Study participants completed pulmonary function testing (PFTs) at several intervals during their HBOT treatment: prior to the first HBOT session, and serially after every 20 subsequent treatments. PFTs were performed using a KoKo Trek USB Spirometer software and pneumotachometer (KoKo, USA), with the assistance of a trained technician and in accordance with industry norms. Retrospectively, PFT data was collected from all enrolled patients' electronic and paper medical charts. This data included anonymized patient demographics, as well as percentage of predicted forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and forced mid-expiratory flow rates (FEF25-75). PFT values underwent statistical analysis to identify potential effects of HBOT on pulmonary function.

Official Title
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Pulmonary Function Following Hyperbaric Oxygen Therapy: A Prospective Cohort Study

Conditions
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Oxygen Toxicity

Intervention / Treatment
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* Device: Hyperbaric Oxygen Therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients scheduled to receive at least ten cycles of HBOT (for any indication) Exclusion Criteria: Inability to provide informed consent
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Hyperbaric Oxygen Therapy - Experimental Group<br>Patients receiving hyperbaric oxygen therapy at the Hyperbaric Medicine Unit (University Health Network, Toronto, ON, Canada) | Device: Hyperbaric Oxygen Therapy<br>* Hyperbaric Oxygen Therapy performed at 100% oxygen at 2.0-2.4 ATA, with 1-3 air breaks, typically at 5 sessions per week, with limited variation depending on the treatment indication and patient/clinician preference.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Percentage Predicted Forced Expiratory Volume in One Second (FEV1%) | The highest value selected from at least three satisfactory pulmonary function tests at each timepoint | Change from baseline FEV1% measured each month until treatment cessation (average of approximately eight weeks) | 
| Change in Percentage Predicted Forced Vital Capacity (FVC%) | The highest value selected from at least three satisfactory pulmonary function tests at each timepoint | Change from baseline FVC% measured each month until treatment cessation (average of approximately eight weeks) | 
| Change in Percentage Predicted Forced Mid-Expiratory Flow Rate (FEF25-75%) | The highest value selected from at least three satisfactory pulmonary function tests at each timepoint | Change from baseline FEF25-75% measured each month until treatment cessation (average of approximately eight weeks) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of Pulmonary Complications following Hyperbaric Oxygen Therapy | Any recorded pulmonary complications of HBOT, including but not limited to lung barotrauma, air embolism, and pneumothorax, identified through retrospective chart review | From date of recruitment until the date of first documented pulmonary complication or most recent follow-up, whichever came first, assessed up to a maximum of 5 years from study recruitment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hyperbaric Oxygen Therapy, Pulmonary Function, Hyperoxia