The effect of the perfluorocarbon emulsion OxycyteTM in an ovine model of severe decompression illness

Abstract

Background: The treatment of decompression sickness (DCS) with hyperbaric oxygen (HBO2) serves to decrease intravascular bubble size, increase oxygen (O2) delivery to tissue and enhance the elimination of inert gas. Emulsified perfluorocarbons (PFC) combined with breathing O2 have been shown to have similar effects animal models. We studied an ovine model of severe DCS treated with the intravenous PFC OxycyteTM while breathing O2 compared to saline control also breathing O2. Methods: Juvenile male sheep (N=67; weight 24.4+/2.10kg) were compressed to 257 feet of sea water (fsw) in our multiple large-animal chamber where they remained under pressure for 31 minutes. Animals then were decompressed to surface pressure and randomized to receive either Oxycyte at 5mL/kg intravenously (IV) or 5mL/kg saline IV (both receiving 100% O2) 10 minutes after reaching surface pressure. Mortality was recorded at two hours, four hours, and 24 hours after receiving the study drug. Surviving animals underwent perfusion fixation and harvesting of the spinal cord at 24 hours. Spinal cord sections were assessed for volume of lesion area and compared. Results: There was no significant difference in survival at two hours (p=0.2737), four hours (p=0.2101), or 24 hours (p=0.3171). Paralysis at 24 hours was not significantly different. However, spinal cord lesion area was significantly smaller in the Oxycyte group as compared to the saline group, with median spinal cord lesion areas 0.65% vs. 0.94% (p=0.0107). Conclusions: In this ovine model of severe DCS the intravenous PFC Oxycyte did not reduce mortality but did ameliorate spinal cord injury when used after the onset of DCS.

Current perspectives of artificial oxygen carriers as red blood cell substitutes: a review of old to cutting-edge technologies using in vitro and in vivo assessments

“…After oxygent infusion, decreased no of platelet found on day 4 which was corrected on day 7. In the case of perftoran infusion, no platelet effect was found Zhu et al ( 2021 ) Dodecafluoropentane (DDFPe) To evaluate the dodecafluoropentane efficacy compared with fresh whole blood (FWB) after resuscitation Male Yorkshire swine (78 ± 5 kg) 2 mL/min of DDFPe; Intravenous DDFPe administration with fresh frozen plasma (FFP) does not enhance survival rate or ameliorate oxygen transport Bonanno et al ( 2018 ) Oxycyte To evaluate the seizure latency (oxygen toxicity of CNS) and duration after PFC administration with 6 ATA of oxygen in swine Yorkshire swine 5 ml/kg of the PFC Oxycyte; Intravenous The result exhibited safety during the use of PFC to treat DCS Mahon et al ( 2013b ) To know the effect of oxycyte after a lateral fluid percussion injury (LFPI) on cognitive recovery and mitochondrial oxygen consumption treatment Rats (Adult male Sprague–Dawley) A lower dose of Oxycyte (4.5 mL/kg); a higher dose of Oxycyte (9.0 mL/kg); Intravenous It showed improvement of cognitive recovery and abated the loss of CA3 neuronal cell Zhou et al ( 2008 ) To assess the effect of PFC oxtcyte™ in severe decompression sickness (DCS) in ovine model Juvenile male sheep (weight 24.4 ± 2.10 kg) 5 ml/kg of the PFC Oxycyte; Intravenous After the onset of DCS, oxtcyte™ reduce injury of the spinal cord although did not decrease the mortality rate Cronin et al ( 2021 ) To know the effect of decreasing the dose of oxycyte (3 cc/kg) in swine model of DCS Yorkshire swine 3 cc/kg of the PFC Oxycyte; Intravenous It improves injury of the spinal cord, but it didn’t significantly increase the survival benefit Mahon et al ( 2013a ) As PFCs showed 50 times more oxygenation than human plasma, so they wanted to evaluate the intravenous dose of the PFC emulsion whether it ameliorate the tissue oxygenation and alleviate the oleic acid lung injury (OALI) effects Yorkshire swine ...…”