Gavage approach to oxygen supplementation with oxygen therapeutic Ox66™ in a hypoventilation rodent model of respiratory distress

Abstract

Acute respiratory distress syndrome (ARDS) features pulmonary dysfunction capable of causing life-threatening hypoxaemia. Ventilation and hyperoxic therapies force oxygen through dysfunctional alveoli but risk exacerbating damage. Ox66™ is an ingestible, solid-state oxygen product designed for oxygen supplementation. Eighteen anaesthetized, ventilated rats were subjected to a 40% reduction in tidal volume to produce a hypoventilatory simulation of the hypoxia in ARDS (HV-ARDS). After 60 min, animals were randomized to receive either normal saline (Saline; volume control) or Ox66^™ gavage. Cardiovascular function and blood oximetry/chemistry were measured alongside interstitial oxygenation (P_ISFO₂) of the peripheral spinotrapezius muscle. HV-ARDS reduced mean arterial pressure by ∼20% and P_ISFO₂ by ∼35% for both groups. Ox66^™ gavage treatment at 60 min improved P_ISFO₂ over Saline (p < .0001), restoring baseline values, however, the effect was temporary. A second bolus at 120 min repeated the OX66^™ P_ISFO₂ response, which remained elevated over Saline (p < .01) until study end and was supported by systemic parameters of lactate, P_aO₂, SO₂, and base deficit. Saline remained hypotensive, whereas Ox66^™ became normotensive. Vasoconstriction was observed in the Saline, but not Ox66^™ group. Supplemental oxygenation through Ox66^™ gavage increased peripheral tissue oxygenation, warranting further study for disorders featuring dysfunction of pulmonary perfusion like ARDS.

Keywords:

• ARDS
• Ox66™
• phosphorescence quenching microscopy
• oxygen
• microcirculation
• COVID-19

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

William Nugent: Study design, data analysis, writing.

Danuel Carr: Data collection, writing

Rosa MacBryde: Data collection

Erica Bruce: Study design, data analysis, writing

Bjorn Song: Study design, data analysis, data collection, writing.

Additional information

Funding

This work was funded by a grant to Dr. Erica Bruce at Baylor University from the Diana Davis Spencer Foundation [Grant Award # 100477].