The partial pressure of oxygen in arterial blood: A relation with different fraction of inspired oxygen and atmospheric pressures

2017 ◽  
Vol 12 (4) ◽  
pp. 280
Author(s):  
NK Agarwal ◽  
Sumit Trivedi
Keyword(s):  
Partial Pressure ◽  
Partial Pressure Of Oxygen ◽  
Arterial Blood ◽  
Fraction Of Inspired Oxygen ◽  
Inspired Oxygen

scholarly journals The incidence, risk factors and prognosis of acute kidney injury in severe and critically ill patients with COVID-19 in mainland China: a retrospective study

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ling Sang ◽  
Sibei Chen ◽  
Xia Zheng ◽  
Weijie Guan ◽  
Zhihui Zhang ◽  
...  
Keyword(s):  
Risk Factors ◽  
Acute Kidney Injury ◽  
Partial Pressure ◽  
Invasive Mechanical Ventilation ◽  
Kidney Injury ◽  
Right Heart Failure ◽  
Partial Pressure Of Oxygen ◽  
Baseline Serum ◽  
Fraction Of Inspired Oxygen ◽  
Inspired Oxygen

Abstract Background The clinical correlates, prognosis and determinants of acute kidney injury (AKI) in patients with coronavirus disease 2019 (Covid-19) remain largely unclear. Methods We retrospectively reviewed medical records of all adult patients with laboratory-confirmed Covid-19 who were admitted to the intensive care unit (ICU) between January 23rd 2020 and April 6th 2020 at Wuhan JinYinTan Hospital and The First Affiliated Hospital of Guangzhou Medical University. Results Among 210 patients, 131 were males (62.4%). The median Age was 64 years (IQR: 56–71). Of 92 (43.8%) patients who developed AKI during hospitalization, 13 (14.1%), 15 (16.3%) and 64 (69.6%) were classified as being at stage 1, 2 and 3, respectively. 54 patients (58.7%) received continuous renal replacement therapy. Age, sepsis, nephrotoxic drug, invasive mechanical ventilation and elevated baseline serum creatinine levels were associated with the occurrence of AKI. Renal recovery during hospitalization was identified among 16 patients with AKI (17.4%), who had a significantly shorter time from admission to AKI diagnosis, lower incidence of right heart failure and higher ratio of partial pressure of oxygen to the fraction of inspired oxygen. Of 210 patients, 93 deceased within 28 days of ICU admission. AKI stage 3, critical disease, greater Age and the lowest ratio of partial pressure of oxygen to the fraction of inspired oxygen being < 150 mmHg were independently associated with death. Conclusions Among patients with Covid-19, the incidence of AKI was high. Our findings of the risk factors of the development of AKI and factors associated with renal function recovery may inform clinical management of patients with critical illness of Covid-19.

scholarly journals Right-to-left shunt determination in dog lungs under inhalation anesthesia with rebreathing and non-rebreathing system

2006 ◽  
Vol 21 (6) ◽  
pp. 374-379 ◽  
Author(s):  
André Leguthe Rosa ◽  
Patrícia Cristina Azevedo Mota ◽  
Yara Marcondes Machado Castiglia
Keyword(s):  
Partial Pressure ◽  
Carbon Dioxide Partial Pressure ◽  
Partial Pressure Of Oxygen ◽  
Intrapulmonary Shunt ◽  
Inhalation Anesthesia ◽  
Arterial Partial Pressure ◽  
Venous Oxygen Saturation ◽  
Fraction Of Inspired Oxygen ◽  
Inspired Oxygen ◽  
Mixed Venous

PURPOSE: To investigatge right-to-left shunt determination in dog lungs under inhalantion anesthesia with non-rebreathing and rebreathing systems and fraction of inspired oxygen (F I O2) of 0.9 and 0.4, respectively. METHODS: Two groups of 10 dogs each under inhalation anesthesia with sevoflurane: GI in which it was utilized non-rebreathing semiclosed system and F I O2 = 0.9, and GII in which it was utilized rebreathing semiclosed system and F I O2 = 0.4. The study parameters were: heart rate, medium arterial pressure, right-to-left intrapulmonary shunt, hematocrit, hemoglobin, arterial partial pressure of oxygen, mixed venous partial pressure of oxygen, mixed venous oxygen saturation, arterial partial pressure of carbon dioxide, partial pressure of water in the alveoli. RESULTS: Shunt results were significantly different between the two groups - GI data were higher than GII in all the evaluated moments. Hence, the group with nonrebreathing (GI) developed a superior grade of intrapulmonary shunt when compared with the rebreathing group (GII). The partial pressure of water in the alveoli was significantly higher in GII. CONCLUSION: The inhalation anesthesia with non-rebreathing system and F I O2 = 0.9 developed a higher grade of intrapulmonary right-to-left shunt when compared with the rebreathing system and F I O2 = 0.4. The higher humidity in GII contributed to the result.

scholarly journals Conservative oxygen supplementation versus usual oxygen supplementation among septic medical intensive care units patients: A before-after investigation

2021 ◽  
Vol 104 (2) ◽  
pp. 003685042110169
Author(s):  
Ying Peng ◽  
Xiaoyan Yuan ◽  
Yi Zhang ◽  
Lei Wang
Keyword(s):  
Intensive Care ◽  
Partial Pressure ◽  
Outcome Measures ◽  
Partial Pressure Of Oxygen ◽  
Oxygen Supplementation ◽  
Number Of Patients ◽  
Target Values ◽  
High Fraction ◽  
Fraction Of Inspired Oxygen ◽  
Inspired Oxygen

Patients admitted in the intensive care unit (ICU) are always managed with excessive high fraction of inspired oxygen and have hyperoxia for a significant period of time, which has potential harms. The guidelines for the management of patients in ICUs do not provide the target values for partial pressure of oxygen or arterial oxyhemoglobin saturations. The study was a before-after investigation comparing two time periods in which different oxygenation strategies were applied. Data of oxygen control, outcome measures, and mortality of a total of 273 patients (>18 years) admitted at least for 2 days in ICUs and received treatment for the sepsis were retrospectively collected and analyzed. Patients were received usual oxygen supplementation (targeted partial pressure of oxygen: 150 mmHg; a high fraction of inspired oxygen: 0.4; UOS cohort; n = 142) or conservative oxygen supplementation (targeted partial pressure of oxygen: 70–100 mmHg; a high fraction of inspired oxygen as low as possible; COS cohort; n = 131). Mechanical ventilation-free hours were significantly higher for patients of COS cohort than those of UOS cohort (77.99 ± 21.26 h/patient vs 70.01 ± 23.57 h/patient, p = 0.016). ICUs length of stays of patients of COS cohort was fewer than those of UOS cohort (7.05 ± 2.13 days/patient vs 7.69 ± 2.43 days/patients, p = 0.016). The probability of survival of patients was higher among patients of COS cohort than those of UOS cohort ( p = 0.049). A higher number of patients from UOS cohort needed vasopressors than those from COS cohort (55 vs 35, p = 0.039). Conservative oxygen supplementation to maintain partial pressure of oxygen was improved outcome measures and decreases mortality as compared to that of usual oxygen supplementation. Level of Evidence: III. Technical Efficacy Stage: 4.

scholarly journals Prone Position in Mechanically Ventilated COVID-19 Patients: A Multicenter Study

2021 ◽  
Vol 10 (5) ◽  
pp. 1046
Author(s):  
Richard Vollenberg ◽  
Philipp Matern ◽  
Tobias Nowacki ◽  
Valentin Fuhrmann ◽  
Jan-Sören Padberg ◽  
...  
Keyword(s):  
Partial Pressure ◽  
Prone Position ◽  
Minute Ventilation ◽  
Significant Negative Correlation ◽  
Lung Compliance ◽  
Mechanically Ventilated ◽  
Arterial Blood ◽  
Fraction Of Inspired Oxygen ◽  
Blood Gas Analyses ◽  
Inspired Oxygen

Background: The prone position (PP) is increasingly used in mechanically ventilated coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS) patients. However, studies investigating the influence of the PP are currently lacking in these patients. This is the first study to investigate the influence of the PP on the oxygenation and decarboxylation in COVID-19 patients. Methods: A prospective bicentric study design was used, and in mechanically ventilated COVID-19 patients, PP was indicated from a partial pressure of oxygen in arterial blood (PaO2)/fraction of inspired oxygen (FIO2) ratio of <200. Patients were left prone for 16 h each. Pressure levels, FIO2, were adjusted to ensure a PaO2 greater than 60 mmHg. Blood gas analyses were performed before (baseline 0.5 h), during (1/2/5.5/9.5/13 h), and after being in the PP (1 h), the circulatory/ventilation parameters were continuously monitored, and lung compliance (LC) was roughly calculated. Responders were defined compared to the baseline value (PaO2/FIO2 ratio increase of ≥15%; partial pressure of carbon dioxide (PaCO2) decrease of ≥2%). Results: 13 patients were included and 36 PP sessions were conducted. Overall, PaO2/FIO2 increased significantly in the PP (p < 0.001). Most PaO2/FIO2 responders (29/36 PP sessions, 77%) were identified 9.5 h after turning prone (14% slow responders), while most PaCO2 responders (15/36 PP sessions, 42%) were identified 13 h after turning prone. A subgroup of patients (interval intubation to PP ≥3 days) showed less PaO2/FIO2 responders (16% vs. 77%). An increase in PaCO2 and minute ventilation in the PP showed a significant negative correlation (p < 0.001). LC (median before the PP = 38 mL/cm H2O; two patients with LC >80 mL/cm H2O) showed a significant positive correlation with the 28 day survival of patients (p = 0.01). Conclusion: The PP significantly improves oxygenation in COVID-19 ARDS patients. The data suggest that they also benefit most from an early PP. A decrease in minute ventilation may result in fewer PaCO2 responders. LC may be a predictive outcome parameter in COVID-19 patients. Trial registration: Retrospectively registered.

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