Oxygenation index (OI) based on arterial blood gas (ABG) test is an invasive procedure and requires indwelling arterial lines. However, the oxygen saturation index (OSI) assessed by the pulse oximetry method is simple and noninvasive for monitoring oxygenation saturation in newborn neonates with chronic lung disease. This study aimed to evaluate and compare OI and OSI among neonates in NICU who underwent mechanical ventilation. A cross-sectional study was carried out among fifty neonates (term and preterm) who were admitted to the NICU of Abuzar Hospital in Ahvaz, Iran. All neonates were examined by both ABG and pulse oximetry methods. Approximately 2 cc of arterial blood sample was taken and sent to the laboratory to determine blood gases. At the same time, the level of peripheral capillary oxygen saturation (SpO) was recorded using a pulse oximeter. OI and OSI were calculated according to their formula. Spearman’ s correlation, linear regression, and Bland-Altman scatter plot were used to determine the correlation, association, and agreement between OI and OSI, respectively. Of the total 50 neonates, 26 were female. The mean (range) gestational age was 35. 28± 3. 01 (28-39) weeks, and post-neonatal age was 6. 05± 7. 04 (1-25) weeks. There was a linear and significant association and correlation between OI and oxygen OSI (P<0. 001), while the Bland-Altman scatter plot confirmed the agreement between them in mean values. Therefore, OSI utilizing pulse oximetry as a noninvasive method can be a substitute for OI in neonates with respiratory failure. It can also reduce workloads and costs.

The Oxygenation Index (OI= [MAP×FiO2]/PaO2×100), an invasive diagnostic criterion, is routinely used as a marker of severity of acute respiratory distress syndrome (ARDS). In order to determine of OI, arterial blood gas (ABG) through an invasive procedure is indispensably used to obtain PaO2. The Oxygenation saturation Index (OSI= [MAP×FiO2]/ SPO2 ×100), as an alternative method, can be implemented using pulse oximetry to assess SpO2. For this epidemiologic-analytic study, 74 intubated patients admitted in a pediatric intensive care unit of Abouzar hospital of Ahvaz during the first 3-day admission were selected equally in pulmonary and non-pulmonary groups within a six months period, from January 1, 2019, to May 31, 2019. Two indexes of OI and OSI in both patients were evaluated, and eventually, the results were analyzed by linear regression using Spss. A comparison of the two OI and OSI indexes showed a meaningful relationship was found (P<0. 001), which has a higher correlation coefficient of 0. 726 in patients with the pulmonary disease than non-pulmonary patients with 0. 394. The present study demonstrates that the index of oxygen saturation (OSI) with a sensitivity of 78% and specificity of 83% in the patients without acute pulmonary distress syndrome is a suitable indicator instead of the invasive index of OI. Also, in patients with pulmonary disease that meet the medium range of Berlin criteria, with a sensitivity of 100% and specificity of 76%, the OSI index can be used to predict the status of patients.

Background: Corrosion and scaling are major problems in the drinking water facilities causing problems such as water loss, recued life of facilities, pipe punctures, clogging of pipes, and pressure loss in drinking water distribution system. This study aims to determine the corrosion and scaling potential in drinking water distribution system of Meshginshahr, Ardebil, Iran. Methods: This descriptive cross-sectional study was conducted during the two seasons (summer and winter) in 2019. A total of 20 water samples, which were obtained by averaging 100 samples, were analyzed to determine the corrosion and scaling potential using Langelier Saturation Index and Ryznar Stability Index. Results: The results showed that the annual average of LSI and RSI were-1. 34 and 10. 03, respectively, indicating that the drinking water of Meshginshahr was corrosive and scale-forming. Conclusion: Therefore, it is necessary to constantly evaluate the drinking water supply resources of this city and try to adjust the pH of water and control other factors affecting corrosion, including concentrations of chloride, dissolved oxygen, and sulfate.

Background: Liver transplant is the only definitive treatment for many patients with end stage liver disease. Presence and severity of preoperative pulmonary disease directly affect the rate of postoperative complications of the liver transplantation. Arterial blood gas (ABG) measurement, performed in many transplant centers, is considered as a traditional method to diagnose hypoxemia. Because ABG measurement is invasive and painful, pulse oximetry, a bedside, noninvasive and inexpensive technique, has been recommended as an alternative source for the ABG measurement.Objectives: The aim of this study was to evaluate the efficacy of pulse oximetry as a screening tool in hypoxemia detection in liver transplant candidates and to compare the results with ABGs.Patients and Methods: Three hundred and ninety transplant candidates (237 males and 153 females) participated in this study. Arterial blood gas oxyhemoglobin saturation (SaO2) was recorded and compared with pulse oximetry oxyhemoglobin saturation (SpO2) results for each participants. The area under the curve (AUC) of receiver operating characteristic (ROC) curves was calculated by means of nonparametric methods to evaluate the efficacy of pulse oximetry to detect hypoxemia.Results: Roc-derived SpO2 threshold of ≤94% can predict hypoxemia (PaO2<60 mmHg) with a sensitivity of 100% and a specificity of 95%. Furthermore, there are associations between the ROC-derived SpO2 threshold of ≤97% and detection of hypoxemia (PaO2<70 mmHg) with a sensitivity of 100% and a specificity of 46%. The accuracy of pulse oximetry was not affected by the severity of liver disease in detection of hypoxemia.Conclusions: Provided that SpO2 is equal to or greater than 94%, attained from pulse oximetry can be used as a reliable and accurate substitute for the ABG measurements to evaluate hypoxemia in patients with end stage liver disease.