Aim: The purpose of this study is to provide information about the effect of the defense mechanism formed by the lung mucosal surface against Covid-19 and the effect of Covid-19's lung involvement on Arterial Blood Gas Values, whose number of cases and mortality rate increases day by day in our country. In addition, by sharing a new method in the diagnosis of Covid-19, important issues in the monitoring of Covid-19 patients with a high symptom burden and high risk of complications associated with lung damage were highlighted. Method: The blood values of 4000 patients who read the consent form and gave consent were collected in the SPSS 26 program in our study conducted in various public hospitals within the city of Istanbul with the permission of Istanbul Provincial Health Directorate with the number 15916306-604.02 and dated 08.09.2020. With our quantitative research, it is possible to interpret the arterial blood gas values of patients who have been diagnosed with covid-19 positive, to determine the common output and to determine the treatment methods, drugs, etc. It is aimed to be a resource for the studies. Common values were searched in the formed control groups and analyzed in accordance with the Henderson-Hasselbalch equation and in accordance with the literature. Arterial and vein blood from the patients participating in the study were collected in anaerobic environment with sterile syringes containing 1.0 or 5.0 mL lyophilized heparin. During blood collection, necessary measures have been taken to prevent or minimize blood contact with air. Since arterial blood gas collection requires expertise, no results that could be interpreted as suspicious were included in the study. Analyzes were performed with pH, pO2, pCO2, HCO3, LDH and Hgb values of 4000 participants. Results: Our study includes 4000 people between the ages of 19-88, who have been diagnosed with Covid-19 and voluntarily agree to participate in our study. 58% of the patients who participated in the study by approving the consent form were male and 42% were female. In order for the blood values of the deceased patients to be used in our study, permission was also requested from their relatives. In this group, 68% of the participants are male and 32% are female participants. It was found that the pO2 and pCO2 ratio of 4000 patients participating in the study did not exceed 10% of the LDH and HCO3 ratio (1O X (LDH) / 100 X (HCO3)> pO2 / pCO2). If the equation is correct in the equation [(LDH) X (pCO2)] / [(HCO3) X (pO2)] ≤ (Hgb), the covid-19 diagnostic status is positive. Conclusion: : It has been determined that the pO2 / pCO2 ratio does not exceed 10% of the LDH / HCO3 ratio in the critical cases examined within the scope of the research. As this rate decreased, the rate of survival of patients also decreased. Therefore, in positive cases, a reference equation that can detect covid-19 positivity has been found by looking at whether there is an anion gap and metabolic acidosis is observed and LDH level. This formula; [(LDH) X (pCO2)] / [(HCO3) X (pO2)] ≤ (Hgb). When the formula was applied, it was determined that the ratio of [(LDH) X (pCO2)] / [(HCO3) X (pO2)] was equal or less than the value of hemoglobin (Hgb).