Oxygen Toxicity
Conditions
Keywords
Hyperbaric Oxygen Therapy, Pulmonary Function, Hyperoxia
Brief summary
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
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.
Interventions
DEVICEHyperbaric Oxygen Therapy
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.
Sponsors
University of Toronto
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
* Patients scheduled to receive at least ten cycles of HBOT (for any indication)
Exclusion criteria
* Inability to provide informed consent
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Percentage Predicted Forced Expiratory Volume in One Second (FEV1%) | The outcome measure was evaluated at baseline (pre-HBOT) and after four weeks (20 treatments), eight weeks (40 treatments), and twelve weeks (60 treatments) | Change from baseline FEV1% defined as the highest value selected from at least three satisfactory pulmonary function tests at each timepoint |
| Change in Percentage Predicted Forced Vital Capacity (FVC%) | The outcome measure was evaluated at baseline (pre-HBOT) and after four weeks (20 treatments), eight weeks (40 treatments), and twelve weeks (60 treatments) | Change from baseline FVC% defined as the highest value selected from at least three satisfactory pulmonary function tests at each timepoint |
| Change in Percentage Predicted Forced Mid-Expiratory Flow Rate (FEF25-75%) | The outcome measure was evaluated at baseline (pre-HBOT) and after four weeks (20 treatments), eight weeks (40 treatments), and twelve weeks (60 treatments) | Change from baseline FEF25-75% defined as the highest value selected from at least three satisfactory pulmonary function tests at each timepoint |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pulmonary Complications Following Hyperbaric Oxygen Therapy | 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 | Any recorded pulmonary complications of HBOT, including but not limited to lung barotrauma, air embolism, and pneumothorax, identified through retrospective chart review |
Countries
Canada
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Hyperbaric Oxygen Therapy - Experimental Group Patients receiving hyperbaric oxygen therapy at the Hyperbaric Medicine Unit (University Health Network, Toronto, ON, Canada)
Hyperbaric Oxygen Therapy: 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. | 86 |
| Total | 86 |
Baseline characteristics
| Characteristic | Hyperbaric Oxygen Therapy - Experimental Group | — |
|---|---|---|
| Age, Categorical <=18 years | 0 Participants | — |
| Age, Categorical >=65 years | 33 Participants | — |
| Age, Categorical Between 18 and 65 years | 53 Participants | — |
| Age, Continuous | 42.5 years STANDARD_DEVIATION 15 | — |
| Body Mass Index | 27.1 kg/m*m STANDARD_DEVIATION 10.3 | — |
| Comorbidities | 123 total comorbidities | — |
| Medications | 115 total medications | — |
| Race and Ethnicity Not Collected | — | — Participants |
| Sex: Female, Male Female | 33 Participants | — |
| Sex: Female, Male Male | 53 Participants | — |
| Smoking Status Current Smoker | 23 Participants | — |
| Smoking Status Former Smoker | 16 Participants | — |
| Smoking Status Never Smoker | 47 Participants | — |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 86 |
| other Total, other adverse events | 53 / 86 |
| serious Total, serious adverse events | 0 / 86 |
Outcome results
Primary
Change in Percentage Predicted Forced Expiratory Volume in One Second (FEV1%)
Change from baseline FEV1% defined as the highest value selected from at least three satisfactory pulmonary function tests at each timepoint
Time frame: The outcome measure was evaluated at baseline (pre-HBOT) and after four weeks (20 treatments), eight weeks (40 treatments), and twelve weeks (60 treatments)
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Expiratory Volume in One Second (FEV1%) | Pre-HBOT | 88.0 Percentage of FEV1 |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Expiratory Volume in One Second (FEV1%) | 20 Treatments | 85.9 Percentage of FEV1 |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Expiratory Volume in One Second (FEV1%) | 40 Treatments | 87.4 Percentage of FEV1 |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Expiratory Volume in One Second (FEV1%) | 60 Treatments | 84.6 Percentage of FEV1 |
Primary
Change in Percentage Predicted Forced Mid-Expiratory Flow Rate (FEF25-75%)
Change from baseline FEF25-75% defined as the highest value selected from at least three satisfactory pulmonary function tests at each timepoint
Time frame: The outcome measure was evaluated at baseline (pre-HBOT) and after four weeks (20 treatments), eight weeks (40 treatments), and twelve weeks (60 treatments)
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Mid-Expiratory Flow Rate (FEF25-75%) | Pre-HBOT | 66.9 Percentage of FEF25-75 |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Mid-Expiratory Flow Rate (FEF25-75%) | 20 Treatments | 66.7 Percentage of FEF25-75 |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Mid-Expiratory Flow Rate (FEF25-75%) | 40 Treatments | 66.2 Percentage of FEF25-75 |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Mid-Expiratory Flow Rate (FEF25-75%) | 60 Treatments | 64.6 Percentage of FEF25-75 |
Primary
Change in Percentage Predicted Forced Vital Capacity (FVC%)
Change from baseline FVC% defined as the highest value selected from at least three satisfactory pulmonary function tests at each timepoint
Time frame: The outcome measure was evaluated at baseline (pre-HBOT) and after four weeks (20 treatments), eight weeks (40 treatments), and twelve weeks (60 treatments)
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Vital Capacity (FVC%) | 20 Treatments | 86.9 Percentage of FVC |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Vital Capacity (FVC%) | 40 Treatments | 89.2 Percentage of FVC |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Vital Capacity (FVC%) | 60 Treatments | 85.9 Percentage of FVC |
| Hyperbaric Oxygen Therapy - Experimental Group | Change in Percentage Predicted Forced Vital Capacity (FVC%) | Pre-HBOT | 88.8 Percentage of FVC |
Secondary
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
Time frame: 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
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Hyperbaric Oxygen Therapy - Experimental Group | Pulmonary Complications Following Hyperbaric Oxygen Therapy | 0 Pulmonary Complications |