Arterial blood gas analysis or venous blood gas analysis for adult hospitalised patients with respiratory presentations: a systematic review.

BACKGROUND: Identification of hypoxaemia and hypercapnia is essential for the diagnosis and treatment of acute respiratory failure. While arterial blood gas (ABG) analysis is standard for PO2 and PCO2 measurement, venous blood gas (VBG) analysis is increasingly used as an alternative. Previous systematic reviews established that VBG reporting of PO2 and PCO2 is less accurate, but the impacts on clinical management and patient outcomes are unknown. AIMS: This study aimed to systematically review available evidence of the clinical impacts of using ABGs or VBGs and examine the arteriovenous difference in blood gas parameters. METHODS: A comprehensive search of the MEDLINE, Embase and Cochrane Library databases since inception was conducted. Included studies were prospective or cross-sectional studies comparing peripheral ABG to peripheral VBG in adult non-critical care inpatients presenting with respiratory symptoms. RESULTS: Of 15 119 articles screened, 15 were included. No studies were found that examined clinical impacts resulting from using VBG compared to ABG. Included studies focused on the agreement between ABG and VBG measurements of pH, PO2, PCO2 and HCO3 -. Due to the heterogeneity of the included studies, qualitative evidence synthesis was performed. While the arteriovenous difference in pH and HCO3 - was generally predictable, the difference in PO2 and PCO2 was more significant and less predictable. CONCLUSIONS: Our study reinforces the notion that VBG is not comparable to ABG for physiological measurements. However, a key revelation from our research is the significant lack of data regarding the clinical implications of using VBG instead of ABG, a common scenario in clinical practice. This highlights a critical knowledge gap.

Consensus of the Brazilian association of hematology, hemotherapy and cellular therapy on patient blood management: Anemia tolerance mechanisms.

Understanding the physiological concepts of oxygen delivery is essential to discern the mechanisms that influence its increase, reduction or maintenance in the body. This text explores the different mechanisms that help maintain oxygen delivery even in the face of reduced hemoglobin levels. Adequate oxygen delivery ensures tissue and metabolic balance, which is crucial to avoid harmful consequences such as metabolic acidosis and cellular dysoxia. The complex interaction between variables such as cardiac output, hemoglobin and heart rate (HR) plays a fundamental role in maintaining oxygen delivery, allowing the body to temporarily adjust to situations of anemia or high metabolic demand. It is important to emphasize that blood transfusions should not be based on fixed values, but rather on individual metabolic needs. Strategies to reduce myocardial consumption and monitor macro and micro hemodynamics help in making rational decisions. Individualizing treatment and considering factors such as blood viscosity in relation to the benefits of transfusion are increasingly relevant to optimize therapy and minimize risks, especially in complex clinical scenarios, such as neurocritical patients and trauma victims.

Consensus of the Brazilian association of hematology, hemotherapy and cellular therapy on patient blood management: Anemia tolerance mechanisms

Abstract Understanding the physiological concepts of oxygen delivery is essential to discern the mechanisms that influence its increase, reduction or maintenance in the body. This text explores the different mechanisms that help maintain oxygen delivery even in the face of reduced hemoglobin levels. Adequate oxygen delivery ensures tissue and metabolic balance, which is crucial to avoid harmful consequences such as metabolic acidosis and cellular dysoxia. The complex interaction between variables such as cardiac output, hemoglobin and heart rate (HR) plays a fundamental role in maintaining oxygen delivery, allowing the body to temporarily adjust to situations of anemia or high metabolic demand. It is important to emphasize that blood transfusions should not be based on fixed values, but rather on individual metabolic needs. Strategies to reduce myocardial consumption and monitor macro and micro hemodynamics help in making rational decisions. Individualizing treatment and considering factors such as blood viscosity in relation to the benefits of transfusion are increasingly relevant to optimize therapy and minimize risks, especially in complex clinical scenarios, such as neurocritical patients and trauma victims.

Exploring the Feasibility of Calculating Expected pCO2 From Venous Blood Gas Samples Alone in Intensive Care Patients.

Introduction This study highlights the significance of assessing acid-base balance and gas exchange in intensive care patients. The research investigates the applicability of using the "expected (pCO2 = HCO3 + 15)" formula, derived from venous blood gas samples, as an alternative to Winter's formula and practical formula. The study emphasizes the importance of identifying the primary acid-base abnormality accurately and efficiently for appropriate clinical intervention in critically ill patients. Methods  This study included 400 adult patients admitted to the Anesthesia Clinic in the Third Stage Anesthesia and Reanimation Intensive Care Unit at Hitit University Erol Olçok Training and Research Hospital between April 2020 and July 2023. Blood gas samples were collected simultaneously from both arterial lines and venous catheters. Patients under 18 years, pregnant women, hemodialysis patients, and those with missing data were excluded. The study aimed to calculate the expected partial pressure of carbon dioxide (pCO2) values using Winter's formula and simple formula for both arterial and venous blood gas samples and assess potential correlations between them. Results The results showed a narrow range for arterial pH values (7.12-7.72), a wider distribution for pCO2 values (17.90-81.30 mmHg), and a moderate dispersion for HCO3 values (12.80-44.33 mmol/L). Both Winter's and simple formulas were applied to estimate the expected pCO2 values, showing strong positive correlations between arterial and venous pH, pCO2, and HCO3 values. The scatterplot illustrated a very high level of association (Pearson's correlation coefficient, r = 1) between the expected pCO2 values derived from both formulas using arterial and venous blood gas samples. Conclusion The clinical study demonstrates that estimating expected pCO2 values in mixed acid-base disorders can be achieved using a simple and convenient formulation, eliminating the need for arterial blood gas sampling and its associated complications.

Arterial Versus Venous Blood Gas Analysis Comparisons, Appropriateness, and Alternatives in Different Acid/Base Clinical Settings: A Systematic Review.

Arterial blood gases (ABGs) are routinely done in critical clinical settings to ascertain acid-base status. Due to difficulties and the potential side effects following arterial blood sampling, much research has been done to find the possibility of using venous samples as an alternative. However, this comparison needs to be evaluated in various contexts. Hence, this systematic review aims to explore the differences, appropriateness, and alternatives of arterial versus venous blood gas (VBG) analysis in different acid-base states. A comprehensive literature search was conducted through electronic databases using the terms "ABG," "VBG," "Arterial Blood Gas," "Venous Blood Gas," and "Gas analysis." Studies' qualities were assessed by using Newcastle - Ottawa Quality Assessment Scale. Of 531 articles, 22 were included in the study after title, abstract, and full-text screening. Based on the Newcastle - Ottawa Quality Assessment Scale, 23% of the studies had good quality (score ≥ 7), 77% fair quality (score 2-6), and none of the studies had poor quality (score ≤ 1). Moreover, 22.5% of the included articles found a strong correlation between ABG and VBG. 73% compared arterial and VBG parameters among patients with any clinical contexts, 22.5% in respiratory diseases, and 4.5% in metabolic conditions, and their results had a significant disparity. There was a considerable discrepancy among authors about the appropriateness and utilization of VBG as an alternative to ABG. Our findings suggest that those studies did not consider physiological differences between venous and arterial blood values and obviated the significance of sampling procedures.

Effect of N95 Filtering Facepiece Respirator on Venous Blood Carbon Dioxide Levels and Hemodynamic Changes in Health Care Workers.

Background: N95 filtering facepiece respirators (FFR) are used by health care workers for prevention of airborne infection, and its use has increased manifolds during COVID-19 pandemic. Prolonged use may result in carbon dioxide (CO2) accumulation, affect hemodynamics, and blood gas values. Although arterial blood gas values accurately measure the blood CO2 levels, venous blood gas values also show acceptable correlation. Aim: To evaluate the physiological impact of N95 FFRs on health care workers, including hemodynamic changes and venous blood levels of CO2 during a period of 6 h. Settings and Design: Prospective observational study in a tertiary care hospital. Methods: The study was conducted on 30 health care workers who performed routine duties while wearing N95 FFR. Venous blood gas values (CO2, pH, and bicarbonate) and vitals (respiratory rate, heart rate, blood pressure, and saturation) were noted at baseline, 2 (T2), and 6 h (T6) after wearing the mask. Discomfort level was also measured on a Visual Analogue Scale (VAS) of 1-10. Statistical Analysis: Repeated measures analysis was done using repeated measures ANOVA or Friedman's test. Group comparisons for continuously distributed data were made using independent sample "t" test or Wilcoxon test. Results and Conclusion: Hemodynamic and blood gas values did not change over time. The VAS for discomfort because of respirator use was 1.33 (1.42) at T2 and 2.77 (1.91) at T6. This was a significant increase in discomfort over time (P = 0.001). About 80% of participants experienced discomfort during this period. N95 FFR did not lead to significant alteration in hemodynamics or change in blood gas values after 6 h of continuous usage. However, discomfort significantly increased over time.

Heparin Concentration in Evacuated Tubes and Its Effect on pH, Ionized Calcium, Lactate, and Potassium in Venous Blood Gas Analysis.

Arterial blood specimens collected in evacuated tubes are unacceptable for blood gas analysis. However, evacuated tubes are routinely used for venous blood-gas analysis. The impact of the blood to heparin ratio on venous blood in evacuated tubes is unclear. Venous blood was drawn into lithium and sodium heparin evacuated tubes that were 1/3 full, ½ full, 2/3 full, and fully filled. Specimens were analyzed for pH, ionized calcium (iCa), lactate, and potassium on a blood-gas analyzer. The results for specimens filled only 1/3 full for lithium and sodium heparin tubes revealed a significant increase in pH and a significant decrease in the iCa. Underfilling the lithium and sodium heparin evacuated tubes did not significantly impact the lactate or potassium results. Venous whole-blood specimens should be filled to at least 2/3 full for accurate pH and iCa results.

Comparison of the predictive ability of lactate and central venous blood gas in pediatric venoarterial mode extracorporeal membrane oxygenation outcome.

BACKGROUND: This study aims to compare lactate and central venous blood gas in the prediction of outcome in pediatric venoarterial mode extracorporeal membrane oxygenation (V-A ECMO). METHOD: This was a retrospective observational study conducted on patients undergoing V-A ECMO care in the pediatric intensive care unit of a tertiary medical center in Taiwan. Patients under 18 years of age undergoing V-A ECMO from January 2009 to April 2019 were included in this study. RESULTS: This study consisted of 47 children who received V-A ECMO with an overall weaning rate of 66.0%. The mean age was 5.5 years and mean ECMO duration was 11.6 days. Successful weaning group had significantly lower lactate levels at initial (58.7 ± 47.0 mg/dL vs. 108.0 ± 55.3 mg/dL, p = 0.003), 0-12 h (37.8 ± 29.0 mg/dL vs. 83.5 ± 60.0 mg/dL, p Z 0.001), and 12-24 h (29.4 ± 26.9 mg/dL vs. 69.1 ± 59.1 mg/dL, p = 0.003) after ECMO initiation; however, the central venous blood gas including pH, HCO3, CO2, base excess (BE), and O2 saturation showed no significant difference. The favorable outcome group had significantly lower lactate levels at 0-12 h (32.8 ± 26.3 mg/dL vs. 71.3 ± 53.3 mg/dL, p = 0.005), and 12-24 h (20.7 ± 10.2 mg/dL vs. 61.9 ± 53.5 mg/dL, p = 0.002); however, the HCO3 levels (26.2 ± 4.5 mmol/L vs. 22.9 ± 6.8 mmol/L, p = 0.042) and BE (2.2 ± 5.4 vs. 2.2 ± 8.5, p = 0.047) were significantly higher at 12-24 h. In multivariate logistic regression, 12-24 h lactate value was an independent factor for unfavorable outcomes (p = 0.015, odds ratio [OR] = 1.1) with the best cut-off value of 48.6 mg/dL (sensitivity 48%, specificity 100%). CONCLUSION: Lactate has better outcome prediction than central venous blood gas in pediatric V-A ECMO. The lactate value 12-24 h after ECMO initiation was an independent factor for unfavorable outcomes.

Accuracy of Potassium Measurement Using Blood Gas Analyzer.

INTRODUCTION: Newer blood gas analyzers can measure both blood gases and electrolytes in both arterial and venous blood samples. They are small, compact, and mobile point of care test (POCT) devices. They can produce results in as short as five minutes. We aimed at assessing the accuracy of potassium (K) level measured by gas analyzer (index test) by comparing that to the regular laboratory machine (reference standard) in our hospital. Our goal is to use POCT result of potassium so we may start insulin infusion within five to 10 minutes of arrival of diabetic ketoacidosis (DKA) patients to the emergency room (ER). It takes an average of 30 minutes to get the result using the reference standard machine. Potassium level is needed urgently in cases of DKA before initiating insulin infusion. That is true also during cardiopulmonary resuscitation (CPR) and while replacing K in severe hypokalemia and during the management of hyperkalemia. METHODS: We looked into the potassium results from 265 patients who had venous blood gas (VBG) or arterial blood gas (ABG) samples and compared that to results of potassium in venous blood samples of these same patients done simultaneously or within two hours. All patients who had blood gas and venous blood drawn simultaneously or within two hours were eligible irrespective of gender, age, diagnosis, and location in the hospital. Data were collected between January 2019 and June 2019. We excluded all cases that were receiving IV fluids, diuretics, or potassium supplements. Samples examined were from all different areas of the hospital including emergency room (ER), intensive care unit (ICU), and general floors. All ages and all diagnoses were included. RESULTS: We used the Bland-Altman method to analyze our data. More than 95% of the data fell within ± 2 standard deviations (S) of the mean difference strongly suggestive of agreement between the index test and the standard reference of the laboratory methods. The bias was 0.19. Lin's concordance correlation coefficient was 0.6584. CONCLUSION: Findings of this study support the use of POCT blood gas analyzer for measuring potassium when the results are needed urgently. When measuring potassium, blood gas analyzers are as accurate as automated analyzers. They produce results in five minutes or so and can be relied upon when potassium level is needed urgently. They are cost-effective and may be available at the bedside.

Histogenous Hypoxia and Acid Retention in Schizophrenia: Changes in Venous Blood Gas Analysis and SOD in Acute and Stable Schizophrenia Patients.

Background: Oxidative stress may play an important role in the pathogenesis of schizophrenia (SCH), and there is considerable indirect evidence that hypoxia is closely related to SCH, but direct evidence of hypoxia in SCH has never been found. Methods:In this study, superoxide dismutase (SOD), venous blood gas, and Positive and Negative Syndrome Scale (PANSS) were examined in 40 SCH patients and compared with those of 40 healthy controls. The patients were treated with combination of atypical antipsychotics and Ditan Huayu Lishen decoction (a Chinese medicine decoction) and examined in the acute and stable period, respectively. Comparisons of indicators between two groups were performed using an independent-samples t-test, comparison of indicators between the acute and stable periods in the SCH group was performed using paired-samples t-test. Pearson correlation and multiple linear regression analyses were performed to investigate the relationships between the effect indicators. Results: Higher venous pH, PvO2, and fasting blood glucose levels and lower SOD, lactic acid, and PvCO2 levels were found in SCH patients compared with the control group; SOD was negatively correlated with the general psychopathology subscale score (PANSS-G), and PvO2 levels were closely related to venous pH in SCH and related to PvCO2 in the control group. It was also found that SOD activity showed no significant difference in acute and stable period, whereas PvO2 showed a downward trend, and venous pH was decreased significantly after treatment. Both the venous pH and PvO2 were higher in patients with SCH than that in healthy controls. Conclusion: It suggests that histogenous hypoxia and acid retention exist in relation to SCH, and there is an improvement of acid retention and a downward trend in histogenous hypoxia after combination treatment. Venous pH, PvO2, and PvCO2 are trait variables, but not state variables of SCH. The theory of histogenous hypoxia and acid retention can well explain the decrease in pH value and the increase in lactic acid in brain tissue of patients with SCH. Histogenous hypoxia and acid retention closely related to glucose metabolism. So they may play an important role in pathophysiology for SCH.

Correlation of Arterial and Venous pH and Bicarbonate in Patients With Renal Failure.

Background and objective Blood gas analysis plays a pivotal role in the management of various respiratory and metabolic disorders. Both arterial and venous samples can be used for blood gas analysis. Arterial blood sampling is technically difficult and is associated with more complications as compared to venous sampling. Many studies have shown the correlation of arterial and venous pH and bicarbonate levels in sepsis, diabetic ketoacidosis (DKA), chronic obstructive pulmonary disease (COPD), and circulatory failure. But, there is a paucity of data, pertaining specifically to the correlation of arterial blood gas (ABG) analysis and venous blood gas (VBG) analysis in patients with renal failure. The objective of this study was to look for any possible correlation between arterial and venous pH and bicarbonate values in patients with renal failure. Methods This cross-sectional study was carried out at a large tertiary care hospital in Rawalpindi, Pakistan. Over a period of eight months, 101 patients with renal failure were enrolled after obtaining informed consent. Arterial and venous samples from the patients were obtained, analyzed, and compared. Results Out of the total 101 patients, 53 (52.5%) were male while 48 (47.5%) were female. The mean age of the patients was 46.23 ±15.54 years. Mean arterial pH and venous pH were 7.35 and 7.28 respectively. The Pearson correlation coefficient between arterial and venous pH was found to be 0.857 (p<0.001). The mean arterial and venous bicarbonate values were 14.47 mEq/L and 15.51 mEq/L respectively. And the Pearson correlation coefficient between arterial and venous bicarbonate was found to be 0.842 (p<0.001).  Conclusion Venous pH and bicarbonate levels correlate strongly with arterial pH and bicarbonate levels, respectively, in patients with renal failure.

Evaluation of Clinical and Venous Blood Parameters as Surrogate Indicators in Assessing the Need for Fasciotomy in Lower Limb Compartment Syndrome.

Acute compartment syndrome in the lower limb, a surgical emergency, may cause ischemic damage to muscles and neurological deficits leading to loss of function of the limb which may even require amputation, thus drastically affecting the quality of life of a patient. Fasciotomy for decompression is suggested when the differential pressure in the compartment of the leg is ≤30 mm Hg. However, compartment pressure measurement is not always feasible. Surgeons often find themselves in a dilemma in deciding the right treatment option for the patient: fasciotomy or conservative management. Since there is no universally accepted reference standard for the diagnosis of acute compartment syndrome at present, there is a need for definitive diagnostic variables so as to not delay fasciotomy in patients who need it, as well as to avoid unnecessary fasciotomies, especially when compartment pressures cannot be measured. In this observational study including 71 patients, based on the compartment pressures of the affected limb, treatment was done either with fasciotomy or conservative approach, and various clinical and biochemical parameters were evaluated in between these two groups. Statistically significant difference was found in the venous blood gas parameters between patients managed conservatively and with fasciotomy (MANOVA, P = .001). The results revealed the association of lower venous blood bicarbonate levels (independent sample t test, P = .021) and the presence of paresthesia (Fisher exact test, P = .0016) with the fasciotomy group. Also, pain on passive stretching of the affected limb was found to be significantly associated with a delta pressure of ≤30 mm Hg in any compartment (Fisher exact test, P = .002). These variables may thus be used as an alternative to the measurement of compartment pressure to assess the requirement of fasciotomy.

Usefulness of peripheral venous blood gas analyses in cats with arterial thromboembolism.

Feline arterial thromboembolism (ATE) is a condition with a high mortality rate. Acid-base abnormalities may be beneficial to the prognosis of cats with ATE. Venous blood gas and electrolytes data on the first day of ATE presentation of 47 cats with ATE were retrospectively reviewed and analysed. The Cox and logistic regression were analysed to evaluate the relationship between acid-base parameters and death. The most common venous acid-base disorder was simple metabolic acidosis. Age, body weight, and partial venous pressure of carbon dioxide (PvCO2) differed between the dead and alive groups within 7 days of the onset of ATE presentation (p < 0.05). Cox-regression showed that increasing age (HR=1.175 [95% CI: 1.027-1.343], p = 0.019), increasing PvCO2 (HR=1.066 [95% CI: 1.010-1.125], p = 0.021) and PvCO2 more than 34 mmHg (HR=7.878 [95% CI: 1.036- 59.915], p = 0.046) were associated with increased hazard of death. Multivariable logistic regression showed that age > 5 years (OR=9.030, 95% CI: 1.258- 64.823; p=0.029), and PvCO2 > 34 mmHg (OR=21.764, 95% CI: 1.747-271.141; p=0.017) were associated with an increased risk of death, while concomitant administration of enoxaparin with clopidogrel (OR=0.111, 95% CI: 0.015-0.795; p=0.029) were associated with a decreased risk of death within 7 days of the onset of ATE presentation. This study demonstrated the power of venous blood gas analysis which may be used as prognostic indicators for cats with ATE.

[The experimental evidence of waveform information in arterial blood gas by beat-by-beat sampling method in human body-the differences of waveform information between arterial and venous blood samples].

Objective: The arterial blood with the oscillatory information comes from the right heart system after gas exchanging in the lung. However, the evidence of the waveform of venous ABG is lack. The objectives of this article are to compare the different information between arterial and venous beat-by-beat blood sample at the same time. Methods: Six post-operative patients with normal heart function and negative Allen test, had been placed the arterial catheterization and central venous catheterization directly connected to pre-heparin plasticpipes for continuous collecting arterial and venous blood. We twisted the 2 pipes into helix formation. After drawing arterial and venous blood with syringes in one heart beat with one helix at the same time, totally 15 heart beats, clipping the pipes with forceps, we put the helix pipe into icedwater at once and analyses PaO2, PaCO2, pH and SaO2 as soon as possible. We selected two breathscycles of waveform from each patient for data calculations of magnitudes and time interval. Results: The heart beat numbers for drawing blood into pipe were 15~16, and all covered more than 2 breathing cycles. There were significant changes of arterial PaO2(i.e. the highest high values compare to the next lowestvalues, P<0.05), but no significant changes in venous blood(P>0.05). The magnitudes of changing PaO2 in arterial and venous blood sample were (9.96±5.18)mmHg and (1.63±0.41)mmHg with significant variance(P=0.010), and they were (8.09±2.43)% and (3.91±1.22)%from their mean with significant variance(P=0.009) respectively. Conclusion: With continuous beat-by-beat arterial and venous blood sampling and ABG analyzing method at the same time, we obtain a clear evidence of periodic parameters ABG waveform, which following breathing cycle, but no clear ABG waveform of the periodic parameters in the venous blood samples, which implies the oscillatory information of the arterial blood with comes from the gas exchanging in the lung.

Recurrent Pyroglutamic Acidosis in the Context of Undiagnosed Liver Cirrhosis-A Case Report.

Metabolic associated fatty liver disease, previously known as nonalcoholic fatty liver disease, is the most common cause of chronic liver disease across all ethnic groups; however, it remains enormously underestimated.1 , 2 Sepsis, hepatotoxic medications and malnutrition in the acute settings on top of unknown cirrhosis can lead to decompensation and various metabolic complications. Pyroglutamic acidosis is a rarely recognised cause for unexplained high anion gap metabolic acidosis that is felt to be frequently underdiagnosed. Particular patients at risk include women, the elderly, those on regular paracetamol and those suffering with malnourishment or sepsis. Other risk factors include alcohol abuse and chronic liver disease (3). We present the case of a patient with recurrent episodes of pyroglutamic acidosis and encephalopathy in the context of undiagnosed nonalcoholic fatty liver disease with cirrhosis.

Predictors of inflammatory lower airway disease in cats presented to the emergency room in respiratory distress: a case-control study.

OBJECTIVES: The objective of the study was to identify whether venous blood gas (VBG) variables may serve as a predictor of inflammatory lower airway disease (ILAD) in cats presenting with respiratory distress. A secondary objective of this study was to compare the diagnostic utility of patient signalment, history and physical examination findings, as compared with VBG variables. METHODS: The medical records of cats presenting with respiratory distress secondary to ILAD (54 cases) and non-ILAD (121 controls) were retrospectively reviewed. RESULTS: No admission VBG variables were predictive of a final diagnosis of ILAD. Comparatively, multivariable analysis identified a history of a cough (P <0.001), increased respiratory rate (P = 0.001), the presence of an abdominal component to respiration (P = 0.007) and the absence of pleural effusion (P <0.01) to be independently associated with a final diagnosis of ILAD. Cats with a history of a cough and an abdominal component to respiration had 7.86 and 5.81 greater odds of being diagnosed with ILAD, respectively. Cats with pleural effusion had 7.43 lower odds of having this final diagnosis. For every 10 breaths/min increase in respiratory rate, cats had 1.48 greater odds of being diagnosed with ILAD. Cats diagnosed with ILAD had a survival rate of 94% (95% CI 84-99%) vs 61% (95% CI 51-70%) for non-ILAD controls (P <0.001). CONCLUSIONS AND RELEVANCE: The results of this study found patient history and physical examination findings to be more useful predictors of a final diagnosis of ILAD in comparison with VBG variables at presentation. A history of a cough, an abdominal component to respiration and a lack of pleural effusion were found to be significant predictors of this diagnosis. Further investigation into the role of respiratory rate in ILAD is warranted.

Agreement between arterial and venous blood gases in trauma resuscitation in emergency department (AGREE).

INTRODUCTION: Arterial blood gas (ABG) sampling is routinely performed in major trauma patients to assess the severity of hemorrhagic shock. Compared to venous blood gas (VBG), ABG is an additional procedure with risks of hematoma and pain. We aim to determine if pH, base deficit (BD), and lactate from VBG and ABG in trauma patients are clinically equivalent. If proven, the need for ABG and its associated risks can be eliminated. METHODS: This prospective observational study was conducted in the Emergency Department of National University Hospital, Singapore, between February and October 2016. We correlated paired ABG and VBG results in adult trauma patients. VBG and ABG were obtained within 10 min and processed within 5 min using a point-of-care blood gas analyzer. Bland-Altman plot analysis was used to evaluate the agreement between peripheral VBG and ABG in terms of pH, base deficit and lactate. RESULTS: There were 102 patients included, with a median age of 34 (interquartile range 28-46) years and male predominance (90.2%). Majority of patients sustained blunt trauma (96.1%), and had injuries of Tier 1 and Tier 2 severity (60/102, 58.8%). Bland-Altman plot analyses demonstrated that only 72.6% of venous pH and 76.5% of venous BD lie within the pre-defined clinically acceptable limits of agreement, whereas 96.0% of venous lactate was within these limits. CONCLUSION: Venous and arterial pH and BD are not within clinically acceptable limits of agreement, and ABG should be obtained for accurate acid-base status. However, venous lactate may be an acceptable substitute for arterial lactate.

Studies on Pathophysiology and Possible Cause of Hie-Symptom ─Findings on Sublingual and Body Surface Temperature, Venous Gas Partial Pressure and the Effects of Oral Administration of PDE-5 Inhibitor Tadarafil─ / 日本温泉気候物理医学会雑誌

  Background and Purpose: Hie-symptom is more common in women, with complains of strong cold sensation of fingers and lower limbs during cold weather. From the cyanotic findings of hands and thighs and dark venous blood, blood stasis due to excessive peripheral vein contraction was suspected. Then we studied the changes of sublingual and body surface temperature, venous gas partial pressure in the warm and cold conditions. To examine the role of thermo-dilating effects of nitric oxide (NO), the effects oral administration PDE 5 inhibitor Tadarafil (TDF) were also studied.   Subjects and Methods: The subjects were 10 women (31 +- 8.8 yrs) with Hie-symptom and 7 women (26+-3.7 yrs) without Hie-symptom, BMI, blood pressure, heart rate,sublingual and peripheral body surface temperature (hand and lower limb), venous and arterial blood gas partial pressure, and fingertip arterial oxygen saturation were measured. The measurement was carried out at warm indoors (about 23°C) and cold outdoors (about 12°C). Then 10 mg TDF tablet was taken and all measurements were repeated again at the same time on the next day.   Results: There was no difference in fingertip arterial blood oxygen saturation in both groups either at indoor or outdoor conditions, and even after taking TDF. In the cold outdoor, the subjects with Hie-symptom, compared to without Hie-symptom, showed significantly lower body surface temperature and venous blood pO2, and increased pCO2. After taking TDF, although sublingual temperature and the decrease in body surface temperature outside the room improved in both groups, the improvement was greater in Hie-symptom.  Consideration and Conclusion: Because of normal fingertip arterial blood oxygen saturation, Hie-symptom is not considered to be a disorder of the cardiopulmonary/arterial system. From a significant decrease in peripheral body surface temperature, and peripheral venous blood pO2, and an increase in pCO2 of Hie-symptom in cold outdoors, it is considered that blood stasis by excessive constriction of peripheral veins or arteriovenous anastomosis (AVA) by the cold. The better effects of oral TDF, in Hie-symptom seems to predict the involvement of NO or cGMP in blood stasis.

Do PaCO2 and peripheral venous PCO2 become comparable when the peripheral venous oxygen saturation is above a certain critical value? / 世界急诊医学杂志（英文）

@#Peripheral venous blood gas (VBG) analysis is increasingly used as an alternative to arterial sampling in Emergency Departments throughout the world.[1] There are multiple advantages using peripheral venous samples for blood gas analysis - technical ease, reduced pain and fewer complications. The difference in sample site chosen for blood gas analysis between European and Australian centres has been notable for members of our author group, prompting discussion and review of the literature.

Studies on Pathophysiology and Possible Cause of Hie-Symptom ─Findings on Sublingual and Body Surface Temperature, Venous Gas Partial Pressure and the Effects of Oral Administration of PDE-5 Inhibitor Tadarafil─ / 日本温泉気候物理医学会雑誌

  Background and Purpose: Hie-symptom is more common in women, with complains of strong cold sensation of fingers and lower limbs during cold weather. From the cyanotic findings of hands and thighs and dark venous blood, blood stasis due to excessive peripheral vein contraction was suspected. Then we studied the changes of sublingual and body surface temperature, venous gas partial pressure in the warm and cold conditions. To examine the role of thermo-dilating effects of nitric oxide (NO), the effects oral administration PDE 5 inhibitor Tadarafil (TDF) were also studied.   Subjects and Methods: The subjects were 10 women (31 +- 8.8 yrs) with Hie-symptom and 7 women (26+-3.7 yrs) without Hie-symptom, BMI, blood pressure, heart rate,sublingual and peripheral body surface temperature (hand and lower limb), venous and arterial blood gas partial pressure, and fingertip arterial oxygen saturation were measured. The measurement was carried out at warm indoors (about 23°C) and cold outdoors (about 12°C). Then 10 mg TDF tablet was taken and all measurements were repeated again at the same time on the next day.   Results: There was no difference in fingertip arterial blood oxygen saturation in both groups either at indoor or outdoor conditions, and even after taking TDF. In the cold outdoor, the subjects with Hie-symptom, compared to without Hie-symptom, showed significantly lower body surface temperature and venous blood pO2, and increased pCO2. After taking TDF, although sublingual temperature and the decrease in body surface temperature outside the room improved in both groups, the improvement was greater in Hie-symptom.  　Consideration and Conclusion: Because of normal fingertip arterial blood oxygen saturation, Hie-symptom is not considered to be a disorder of the cardiopulmonary/arterial system. From a significant decrease in peripheral body surface temperature, and peripheral venous blood pO2, and an increase in pCO2 of Hie-symptom in cold outdoors, it is considered that blood stasis by excessive constriction of peripheral veins or arteriovenous anastomosis (AVA) by the cold. The better effects of oral TDF, in Hie-symptom seems to predict the involvement of NO or cGMP in blood stasis.