High-flow nasal cannula oxygen versus conventional oxygen therapy in a rat model of severe carbon monoxide toxicity

Background: This study compared the efficacy of high-flow nasal cannula (HFNC) oxygen therapy with conventional oxygen therapy (COT) using a simple face mask for clearing carbon monoxide (CO) from the bloodstream in a rat model of severe CO poisoning. Methods: Twenty-eight male Wistar rats were assigned to four groups: severe CO intoxication treated with HFNC, a sham group (no intoxication or treatment), severe CO intoxication treated with COT, and a control group with severe CO intoxication receiving no treatment. Their arterial blood gas and metabolic parameters were analyzed and compared to determine treatment effectiveness. Results: Significant differences were observed among the groups in terms of carboxyhemoglobin (COHb), pH, bicarbonate (HCO3), hemoglobin, sodium (Na), potassium (K), calcium (Ca), glucose and lactate levels. Both treatment groups had lower COHb and lactate levels compared to the untreated control group, with COHb clearance being significantly higher in the HFNC group than in the COT group (20.33% ± 3.58% vs. 41.17% ± 6.49%; p < 0.001). Additionally, pH levels were higher in the HFNC group than in the COT group (7.32 ± 0.07 vs. 7.27 ± 0.05; p = 0.486). Conclusions: HFNC oxygen therapy was found to be more effective than COT in promoting CO elimination and improving arterial blood gas parameters, indicating its potential as a superior treatment strategy for severe CO poisoning.

Carbon monoxide poisoning; Carboxyhemoglobin; High-flow nasal cannula; Conventional oxygen therapy; Arterial blood gas

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