Introduction: The necessary tools for oxygen therapy are divided into two main groups: high flow and low flow systems. In low flow oxygen systems, the patients breathe the room air with oxygen. Few studies have been conducted regarding comparison of efficacy of high and low flow oxygen therapy methods. Hence, conducting a study to compare low and high flow oxygen therapy methods in lung contusion patients is essential.

Method: The study was cross-sectional with descriptive-analytical design. Totally 100 lung contusion patients with PaO₂/FiO₂ < 200, randomly divided into two groups of 50: the first group received high flow oxygen therapy and the second low flow (oxygen with ordinary mask with 8 liters per minute flow). Respiratory parameters were measured at the admission and reevaluated 48 hours after the start of oxygen therapy. These parameters were breaths per minute, PaO₂/FiO₂, PO₂, PCO₂, and patient satisfaction with oxygen therapy. A checklist along with demographic information was used to collect data that was analyzed in SPSS20.

Results: The results showed that 5 (10.4%) people had good satisfaction in the case group but 11 (23.4%) in the control group. Overall, there were no significant differences between the two groups in terms of satisfaction with oxygen therapy. Mean PO₂, PCO₂ and patients’ respiratory rate at admission did not significantly differ between the case and control groups. However, mean PO₂ after 48 hours was significantly higher in the case group compared to the control group (p-value = 0.000), and the respiratory rate after 48 hours in the case group was significantly lower in the case group compared to in the control group (p-value = 0.000). Nonetheless, mean PCO₂ after 48 hours did not differ significantly between the two groups (p-value = 0.307).

Conclusion: The results showed that the patients treated using high flow oxygen system had better respiratory parameters compared to the patients treated with low flow oxygen system, but patients’ satisfaction did not differ significantly after treatment software.

oxygen therapy, high flow, lung contusion.