Adjunct Hyperbaric Oxygen Therapy for Refractory Infections in Patients with Hematologic Malignancies: A Single-Center Retrospective Study

Background: As hyperbaric oxygen therapy has been sporadically used in combination with antimicrobial treatment for refractory infections in patients with hematologic malignancies, data on its efficacy and outcomes are limited. Methods: We retrospectively analyzed 55 patients with hematologic malignancies treated with hyperbaric oxygen therapy over a 10-year period at a single tertiary care center and report on patients’ clinical features, infection types, treatment responses, and survival outcomes. Results: The most common underlying hematologic malignancy diagnosis was acute myeloid leukemia (30 patients, 55%). The most common hyperbaric oxygen therapy indications were invasive mold disease (IMD) (35 patients, 64%), BK virus-associated cystitis (17 patients, 31%), and bacterial cellulitis (3 patients, 5%). Patients underwent a median of 10 hyperbaric oxygen therapy sessions (range, 1–45). In total, 54 (98%) of the 55 patients were evaluable for response, of whom 32 (59%) patients demonstrated a response, defined as either resolution or stabilization of the infection. Among the 35 patients with IMDs, we found that 11 patients (31%) achieved a complete response, 5 (14%) had a partial response, 6 (17%) had stable disease, and 13 (37%) patients experienced progression of their infection. In contrast, among the 17 patients with BK virus-associated cystitis, 9 patients (53%) had persistent or worsening hematuria. The two evaluable patients with bacterial cellulitis responded with resolution of the infection. We reviewed the status of the hematologic malignancies at the time of hyperbaric oxygen therapy treatment and found that the 21 patients whose hematologic malignancies were in remission tended to have a higher response rate of their infection compared to patients whose hematologic malignancies were not in remission (73% vs. 46% p = 0.057). Despite the response of infections, 1-year mortality in these patients remained high at 76%. Conclusions: Based on our experience, hyperbaric oxygen therapy, in conjunction with appropriate anti-infective therapy and debridement surgery, could benefit selected patients with hematologic malignancies, especially those whose underlying disease is controlled but experience recalcitrant bacterial or fungal infections.