Protocol for an International, Multicenter, Hyperbaric Oxygen Treatment Registry and Research Consortium

Background: Background: Hyperbaric oxygen (HBO2) (oxygen at pressures higher than atmospheric) is approved for 14 indications by the Undersea and Hyperbaric Medical Society. HBO2's main effect is to increase oxygen content in plasma and body tissues, which can counteract hypoxia or ischemia. Laboratory studies show that hyperbaric oxygen has effects beyond relieving hypoxia (e.g. promoting angiogenesis in irradiated tissue, anti-inflammatory effects, radiosensitization of tumors, hypoxia preconditioning, fungal growth inhibition) and has potential to treat conditions such as inflammatory bowel disease and pyoderma gangrenosum. Lack of consistently-collected outcomes data on a large cohort of individuals receiving HBO2 therapy limits its use for both established and new indications. A course of therapy often involves 30-40 visits to a hyperbaric chamber, so the numbers of patients seen at any given center is constrained by chamber capacity. As a result, published HBO2 outcomes data tend to be from small case series, because few patients with a particular condition are treated at a given center. To solve this problem, a registry that collects and pools data systematically from multiple institutions has been established.

Objective: Objective: Collect consistent outcome-data across multiple hyperbaric centers to assess treatment effectiveness and establish a research consortium.

Methods: Methods: A consortium of hyperbaric centers who have agreed to collect consistent outcomes data on all patients seen has been assembled. Data are collected at each participating center using Research Electronic Data Capture (REDCap), a web-based, data collection system used frequently for research. Standard outcomes measures have been defined for each condition, which are programmed into the REDCap data collection templates. Governance is through a consortium agreement that defines data security, data sharing, publications, liability, and other issues. Centers obtain IRB/ethics approval to participate either at their own institution or by relying on the IRB at the coordinating center (Dartmouth). Dissemination will occur through a yearly report and by publications based on the data in the registry.

Results: Results: Early results from some common indications show significant pre to post treatment changes. Additional indications and outcome measures are being added using the procedures outlined in the consortium agreement.

Conclusions: Conclusions: The registry collects consistent outcome information for a therapy that needs further study and a stronger evidence base. It also overcomes the challenge of collecting adequate patient numbers for both established and emerging indications by combining data collection from multiple centers. The data entry requirements should be within the capabilities of existing staff at any given hyperbaric center. By using REDCap, the registry can be expanded to include detailed information on particular indications and long-term follow-up on selected patients without significantly increasing the basic data entry requirements. Through the registry a network of enrolled hyperbaric centers has been established that provides the basis for a clinical trials network.