The effectiveness of the inclusion of hyperbaric oxygenation in the complex therapy of patients with COVID-19: retrospective study

INTRODUCTION: The pandemic of novel coronavirus disease (COVID-19) caused by the SARS-CoV-2 virus has forced physicians to reconsider traditional approaches to the treatment of patients with viral pneumonia and acute respiratory distress syndrome, when normobaric oxygenation methods were ineffective. The way out of this situation was the inclusion of hyperbaric oxygenation in the complex therapy of patients with COVID-19, as a recognized means of eliminating any form of oxygen debt due to more efficient delivery of oxygen to organs and tissues. OBJECTIVE: To evaluate the effectiveness of hyperbaric oxygenation in the complex therapy of patients with a novel coronavirus infection with severe lung damage (more than 50%). MATERIALS AND METHODS: We examined 75 patients with the diagnosis «Coronavirus infection caused by the virus SARS-CoV-2» (64 patients with CT-3, 11 patients with CT-4), 50 of whom were prescribed a course of hyperbaric oxygen therapy (HBOT). The procedures were carried out in a Sechrist 2800 resuscitation pressure chamber (USA) at 1.4–1.6 ATA for no more than 60 minutes. Before and after each HBOT session, subjective indicators of the patients’ condition were assessed and blood oxygen saturation was measured. In addition, the dynamics of the level of leukocytes, platelets, ALT, AST and C-reactive protein were evaluated. In order to analyze oxygen support, the type (low-flow oxygen therapy, high-flow oxygen therapy) and daily oxygen consumption were recorded.

RESULTS: The inclusion of hyperbaric oxygenation in the complex therapy of patients with a novel coronavirus infection led to a significant increase in the level of SpO2 by the 7th day in the study group to 92% (89; 94) vs. 88% (87; 92) in the control group (p=0.011), and by 14th day to 96% (95; 97) vs. 95% (90; 96) (p<0.001). This circumstance led to a significant decrease in the number of patients requiring additional oxygen support, which was 94% in the study group and 100% in the control group by the 7th day, and 16% in the study group and 44% in the control group by the 14th day. In particular, the number of patients requiring high-flow oxygen therapy in the study group decreased from 34% on the 5th day to 2% on the 14th day, while in the control group over the same period there was a decrease from 60% to 32%. When analyzing the volumetric oxygen consumption in the study group, even taking into account the oxygen consumption for hyperbaric oxygenation, a decrease in the average daily oxygen consumption was recorded from 13.9 L/min on the 5th day to 9.3 L/min on the 14th day, while in the control group for the same period from 17.2 L/min to 14.5 L/min. The length of stay of patients in the intensive care unit in the study group was 10 (8; 12) vs. 13 (11; 23) bed-days (p=0.002) in the control group, and the total length of hospitalization was 16 (13.3; 20) vs. 21 (19; 29) bed-days (p><0.001) in the study and control groups, respectively. DISCUSSION: The early inclusion of hyperbaric oxygen therapy in the complex therapy of patients with a new coronavirus infection led to a significant increase in the level of SpO2 starting from the 7th day. This circumstance led to a significant decrease in number of patients requiring additional oxygen support in the study group compared to the control. This, in turn, affected the reduction in volumetric oxygen consumption in the study group, even taking into account the oxygen consumption on hyperbaric oxygenation. In addition, in the study group, positive dynamics according to CT data, a more rapid decrease in the level of C-reactive protein, were more often recorded. All these observations indicate a more rapid normalization of the state of the body due to the elimination of hypoxia, a decrease in the inflammatory response and restoration of lung function in patients who underwent hyperbaric oxygen therapy. CONCLUSION: The inclusion of HBO in the complex therapy of patients with a new coronavirus infection with severe lung damage (more than 50%) allows to stabilize the condition in a short time due to a more intensive decrease in the degree of lung damage according to CT data, early refusal of additional oxygen support, improvement of the psycho-emotional state, which in generally leads to a reduction in the length of stay of patients both in the ICU and in the hospital department.>< 0.001). This circumstance led to a significant decrease in the number of patients requiring additional oxygen support, which was 94% in the study group and 100% in the control group by the 7th day, and 16% in the study group and 44% in the control group by the 14th day. In particular, the number of patients requiring high-flow oxygen therapy in the study group decreased from 34% on the 5th day to 2% on the 14th day, while in the control group over the same period there was a decrease from 60% to 32%. When analyzing the volumetric oxygen consumption in the study group, even taking into account the oxygen consumption for hyperbaric oxygenation, a decrease in the average daily oxygen consumption was recorded from 13.9 L/min on the 5th day to 9.3 L/min on the 14th day, while in the control group for the same period from 17.2 L/min to 14.5 L/min. The length of stay of patients in the intensive care unit in the study group was 10 (8; 12) vs. 13 (11; 23) bed-days (p=0.002) in the control group, and the total length of hospitalization was 16 (13.3; 20) vs. 21 (19; 29) bed-days (p< 0.001) in the study and control groups, respectively.

DISCUSSION: The early inclusion of hyperbaric oxygen therapy in the complex therapy of patients with a new coronavirus infection led to a significant increase in the level of SpO2 starting from the 7th day. This circumstance led to a significant decrease in number of patients requiring additional oxygen support in the study group compared to the control. This, in turn, affected the reduction in volumetric oxygen consumption in the study group, even taking into account the oxygen consumption on hyperbaric oxygenation. In addition, in the study group, positive dynamics according to CT data, a more rapid decrease in the level of C-reactive protein, were more often recorded. All these observations indicate a more rapid normalization of the state of the body due to the elimination of hypoxia, a decrease in the inflammatory response and restoration of lung function in patients who underwent hyperbaric oxygen therapy.

CONCLUSION: The inclusion of HBO in the complex therapy of patients with a new coronavirus infection with severe lung damage (more than 50%) allows to stabilize the condition in a short time due to a more intensive decrease in the degree of lung damage according to CT data, early refusal of additional oxygen support, improvement of the psycho-emotional state, which in generally leads to a reduction in the length of stay of patients both in the ICU and in the hospital department.