Clinical and biochemical short-term effects of hyperbaric oxygen therapy on SARS-Cov-2+hospitalized patients with hypoxemic respiratory failure

Background: Hyperbaric oxygen therapy (HBOT) has been proposed to address COVID-19-associated respiratory failure. However, its biochemical effects are poorly known. Method: 50 patients with hypoxemic COVID-19 pneumonia were divided into C group (standard care) and H group (standard care plus HBOT). Blood was obtained at t = 0 and t = 5 days. Oxygen saturation (O2 Sat) was followed up. White blood cell (WC) count, lymphocytes (L) and platelets (P) and serum analysis (glucose, urea, creatinine, sodium, potassium, ferritin, D dimer, LDH and CRP) were carried out. Plasma levels of sVCAM, sICAM, sPselectin, SAA and MPO, and of cytokines (IL-1 beta, IL-1RA, IL-6, TNF alpha, IFN alpha, IFN gamma, IL-15, VEGF, MIP1 alpha, IL-12p70, IL-2 and IP-10) were measured by multiplex assays. Angiotensin Converting Enzyme 2 (ACE-2) levels were determined by ELISA. Results: The average basal O2 Sat was 85 +/- 3%. The days needed to reach O2 Sat >90% were: H: 3 +/- 1 and C: 5 +/- 1 (P < 0,01). At term, H increased WC, L and P counts (all, H vs C: P < 0,01). Also, H diminished D dimer levels (H vs C, P < 0,001) and LDH concentration (H vs C, P < 0.01]. At term, H showed lower levels of sVCAM, sPselectin and SAA than C with respect to basal values (H vs C: Delta sVCAM: P < 0,01; Delta sPselectin: P < 0,05; Delta SAA: P < 0,01). Similarly, H showed diminished levels of TNF alpha (Delta TNF alpha: P < 0,05) and increased levels of IL-1RA and VEGF than C respect to basal values (H vs C: Delta IL-1RA and Delta VEGF: P < 0,05). Conclusion: Patients underwent HBOT improved O2 Sat with lower levels of severity markers (WC and platelets count, D dimer, LDH, SAA). Moreover, HBOT reduced proinflammatory agents (sVCAM, sPselectin, TNF alpha) and increased anti-inflammatory and pro-angiogenic ones (IL-1RA and VEGF).

Automated summary

COVID-19 patients who received hyperbaric oxygen therapy showed faster improvement in oxygen saturation, increased white blood cell count, lymphocytes count, and platelet count, decreased D-dimer and lactate dehydrogenase concentration, as well as reduced levels of inflammatory markers.