A comparison of two hyperbaric oxygen regimens: 2.0 ATA for 120 minutes to 2.4 ATA for 90 minutes in treating radiation-induced cystitis Are these regimens equivalent?

Abstract

Hyperbaric oxygen dosing variations exist in radiation cystitis treatment. The objectives of this study were to compare response and safety rates among patients with radiation cystitis treated with different protocols: 2.0 ATA (atmospheres absolute) for 120 minutes at the University of Pennsylvania; and 2.4 ATA for 90 minutes at Hennepin Healthcare. Retrospective chart review of radiation cystitis patients treated with hyperbaric oxygen at the University of Pennsylvania (January 2010-December 2018) and Hennepin Healthcare Minnesota (January 2014-December 2018). Primary outcome was response to treatment. Complications were limited to hyperbaric-related conditions. Regression analysis was performed with ordinal logistic regression and binary logistic regression. 126 patients were included in the analysis (2.0 ATA: 66, 2.4 ATA: 60). Overall response rate was 75.4% (good) and was not significantly different between protocols (good response: 2.0 ATA 72.7% vs. 2.4 ATA 78.3% p=0.74). The 2.0 ATA group required additional treatments [2.0 ATA: 45.45 ± 14.5 vs. 2.4 ATA: 40.03 ± 9.7, p<0.05]. 6.1% (2.0 ATA) and 13.3% (2.4 ATA) required tympanostomy tube placement or needle myringotomy for otic barotrauma (p=0.22). Transfusion was associated with poorer outcomes (p<0.05). Both groups - 2.0 ATA and 2.4 ATA - had similar response and complication rates. Blood transfusion is a negative prognostic factor for treatment outcome.