Search

BackgroundInfants with hypoxic-ischemic encephalopathy are often treated with therapeutic hypothermia and high-frequency ventilation. Fluctuations in PaCO2 during therapeutic hypothermia are associated with poor neurodevelopmental outcomes. Transcutaneous CO2 monitors offer a noninvasive estimate of PaCO2 represented by transcutaneously measured partial pressure of carbon dioxide (PtcCO2 ). We aimed to assess the precision between PtcCO2 and PaCO2 values in neonates undergoing therapeutic hypothermia.MethodsThis was a retrospective chart review of 10 neonates who underwent therapeutic hypothermia requiring respiratory support over 2 y. A range of 2-27 simultaneous PtcCO2 and PaCO2 pairs of measurements per neonate were analyzed via linear mixed models and a Bland-Altman plot for multiple observations per neonate.ResultsA linear mixed-effect model demonstrated that PtcCO2 and PaCO2 (controlling for sex) were similar. The 95% CI of the mean difference ranged from -2.3 to 5.7 mm Hg (P = .41). However, precision was poor as the PtcCO2 ranged from > 18 mm Hg to < 13 mm Hg than PaCO2 values for 95% of observations.ConclusionsThe neonates' PtcCO2 was as much as 18 mm Hg higher to 13 mm Hg lower than the PaCO2 95% of the time. Transcutaneous CO2 monitoring may not be a good trending tool, nor is it appropriate for estimating PaCO2 in patients undergoing therapeutic hypothermia.

Objective To explore the application effect of risk management based on nursing quality sensitive indicators in elderly patients with severe pneumonia. Methods A total of 94 elderly patients with severe pneumonia admitted to the Respiratory Department of Zhengzhou Yihe Hospital from May 2021 to May 2023 were selected as the study subjects. The 94 elderly patients with severe pneumonia were divided into the control group and the observation group using a random number table method, with 47 cases in each group. The patients in the control group were given routine nursing care, while the patients in the observation group were given risk management based on sensitive indicators of nursing quality. Both groups continued to receive care until the patients were discharged. The nursing management effects of the two groups were compared. Results The indexes of blood gas analysis in the two groups after nursing were better than those before nursing, and the partial pressure of carbon dioxide in the observation group was lower than that in the control group, with statistical significances（P＜0. 05). The arterial oxygen partial pressure, oxygen and index in the observation group were higher than those in the control group after nursing, but the differences were not statistically significant（P＞0. 05). The duration of mechanical ventilation and hospitalization in the observation group were shorter than those in the control group, and the total incidence of nursing adverse events such as ventilator-associated pneumonia and falling off the bed was lower than that in the control group. The scores of SF-36 and the scores of nursing satisfaction were higher than those in the control group, with statistical significances（P＜0. 05). Conclusion After risk management intervention based on nursing quality sensitive indicators, elderly patients with severe pneumonia can improve their blood gas analysis indicators, further shorten their mechanical ventilation time, reduce hospital stay, reduce nursing adverse events such as ventilator-associated pneumonia and falls, promote the improvement of patient quality of life, and achieve satisfactory nursing outcomes. [ABSTRACT FROM AUTHOR]

Background: Minimizing air aspiration by carefully filling blood gas syringes is crucial to prevent air contamination from causing undesirable variations in gasses and other molecules. While some previous studies investigated this aspect, these are now outdated and only analyzed a limited number of blood gas parameters. Thus, we investigated the effects air contamination in the syringe using a modern blood gas analyzer. Methods: We sampled venous blood from 17 laboratory workers (mean age: 46±11 years; 10 women), filling two consecutive blood gas syringes. The first was filled exactly to its nominal volume (i.e., 1.0 mL), while the second was filled with 0.8 mL of blood and 0.2 mL of ambient air. Blood gas analysis was performed in each syringe using an identical analyzer. Results: In the syringe with the air bubble, we found statistically significant increase in pH (0.1%), pO2 (10.8%), SO2 (11.2%), total hemoglobin (3.0%), and hematocrit (2.7%), while values of pCO2 (-4.8%), sodium (-0.5%), and ionized calcium (-1.3%) were significantly reduced. With exception of pH, all these changes exceeded the performance specifications. Potassium, chloride, glucose, lactate, COHb and MetHb values remained unchanged. Conclusions: These findings confirm that air bubbles must be removed as soon as possible after sampling from blood gas syringes to prevent artifactual test results and misleading clinical judgment and inappropriate treatment. When blood gas syringes are received in the laboratory with air bubbles inside, the most vulnerable parameters (i.e., pO2, SO2, pCO2, sodium, ionized calcium, hematocrit and hemoglobin) should be suppressed. [ABSTRACT FROM AUTHOR]

Prehospital blood gas analysis (BGA) is an evolving field that offers the potential for early identification and management of critically ill patients. However, the utility and accuracy of prehospital BGA are subjects of ongoing debate. We aimed to provide a comprehensive summary of the current literature on prehospital BGA, including its indications, methods, and feasibility. We performed a scoping review of prehospital BGA. A thorough search of the PubMed, Embase, and Web of Science databases was conducted to identify relevant studies focusing on prehospital BGA in adult patients. Fifteen studies met the inclusion criteria. Prehospital BGA was most frequently performed in patients in out-of-hospital cardiac arrest, followed by traumatic and nontraumatic cases. The parameters most commonly analyzed were pH, pCO 2 , pO 2 , and lactate. Various sampling methods, including arterial, venous, and intraosseous, were reported for prehospital BGA. While prehospital BGA shows promise in facilitating early identification of critical patients and guiding resuscitation efforts, logistical challenges are to be considered. The handling of preclinical BGA is described as feasible and useful in most of the included studies. Prehospital BGA holds significant potential for enhancing patient care in the prehospital setting, though technical challenges need to be considered. However, further research is required to establish optimal indications and demonstrate the benefits for prehospital BGA in specific clinical contexts. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of contamination of venous blood with a lipid-containing solution on parameters measured by a modern blood gas analyzer. We collected venous blood from 17 healthcare workers (46 ± 11 years; 53 % women) into three blood gas syringes containing 0 , 5 and 10 % lipid-containing solution. Blood gas analysis was performed within 15 min from sample collection on GEM Premier 5000, while triglycerides and serum indices were assays on Roche COBAS C702. Triglycerides concentration increased from 1.0 ± 0.3 mmol/L in the uncontaminated blood gas syringe, to 39.4 ± 7.8 and 65.3 ± 14.4 mmol/L (both p<0.001) in syringes with 5 and 10 % final lipid contamination. The lipemic and hemolysis indices increased accordingly. Statistically significant variation was noted for all analytes except hematocrit and COHb in the syringe with 5 % lipids, while only COHb did not vary in the syringe with 10 % lipids. Significant increases were observed from 5 % lipid contamination for pO2, SO2 and lactate, while the values of pH, pCO2, sodium, potassium, chloride, ionized calcium, glucose, hematocrit (10 % contamination), hemoglobin and MetHB decreased. All these changes except lactate and CoHb exceeded their relative performance specifications. Artifactual hyperlipidemia caused by contamination with exogenous lipids can have a clinically significant impact on blood gas analysis. Manufacturers of blood gas analyzers must be persuaded to develop new instruments equipped with serum indices. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examines ways in which heat stress affects the behavior and health of dairy cows using advanced monitoring technologies. Higher levels of heat stress significantly reduce the time cows spend ruminating and increase their body temperature. Furthermore, key blood gas parameters are altered, indicating changes in the cows' metabolic state. Cows within the highest THI classification group (73–78) showed a reduction in partial carbon dioxide pressure (pCO2), a 32% increase in partial oxygen pressure (pO2), a decrease in sodium by 1.36%, and a decrease in potassium by 6%, while chloride levels increased by 3%. These findings highlight the importance of using innovative technologies to monitor and manage heat stress in dairy cows to ensure their health and productivity. They may also serve as an early indicator, allowing time to implement management changes to reduce the impact of heat stress. Heat stress (HS) is one of the key factors affecting an animal's immune system and productivity, as a result of a physiological reaction combined with environmental factors. This study examined the short-term effects of heat stress on cow behavior, as recorded by innovative technologies, and its impact on blood gas parameters, using 56 of the 1070 cows clinically evaluated during the second and subsequent lactations within the first 30 days postpartum. Throughout the experiment (from 4 June 2024 until 1 July 2024), cow behavior parameters (rumination time min/d. (RT), body temperature (°C), reticulorumen pH, water consumption (L/day), cow activity (h/day)) were monitored using specialized SmaXtec boluses and employing a blood gas analyzer (Siemens Healthineers, 1200 Courtneypark Dr E Mississauga, L5T 1P2, Canada). During the study period, the temperature–humidity index (THI), based on ambient temperature and humidity, was recorded and used to calculate THI and to categorize the data into four THI classes as follows: 1—THI 60–63 (4 June 2024–12 June 2024); 2—THI 65–69 (13 June 2024–18 June 2024); 3—THI 73–75 (19 June 2024–25 June 2024); and 4—THI 73–78 (26 June 2024–1 July 2024). The results showed that heat stress significantly reduced rumination time by up to 70% in cows within the highest THI class (73 to 78) and increased body temperature by 2%. It also caused a 12.6% decrease in partial carbon dioxide pressure (pCO2) and a 32% increase in partial oxygen pressure (pO2), also decreasing plasma sodium by 1.36% and potassium by 6%, while increasing chloride by 3%. The findings underscore the critical need for continuous monitoring, early detection, and proactive management to mitigate the adverse impacts of heat stress on dairy cow health and productivity. Recommendations include the use of advanced monitoring technologies and specific blood gas parameter tracking to detect the early signs of heat stress and implement more timely interventions. [ABSTRACT FROM AUTHOR]

Objective By screening and passaging G0 generation Wistar rats, we obtained hypoxiasensitive and hypoxia-tolerant G1 generation rats, and then the differences in hypoxia sensitivity among these rats were preliminarily explored. Methods 200 Wistar rats (half male and half female) were selected as G0 generation and placed in a controlled oxygen concentration system. The hypoxia tolerance time, which refers to the time from placement to near death, was recorded for the G0 generation rats at an oxygen volume fraction of 3%. 30 rats (half male and half female) with the shortest hypoxia tolerance time were selected for mating and passage to obtain G1 generation hypoxia-sensitive rats. Similarly, 30 rats (half male and half female) with the longest hypoxia tolerance time were selected for mating and passage to obtain G1 generation hypoxia-tolerant rats. An additional 24 standard Wistar rats were randomly divided into two groups: a control group and a model group, with 12 rats in each group (half male and half female). The control group was kept in a normoxic environment, while the model group, along with the G1 generation hypoxia-sensitive rats (G1 sensitive group) and G1 generation hypoxia-tolerant rats (G1 tolerant group), were placed in a hypobaric hypoxia chamber (simulating an altitude of 5 000 m). After 12 hours, various indicators, including blood gas, complete blood count, blood biochemistry, pathological sections, and hypoxia-related genes were detected or observed to compare the differences in hypoxia sensitivity among the 4 groups. Results Compared with the G0 genera3tion standard rats, the hypoxia tolerance time of G1 generation rats was significantly prolonged (P<0.01). Compared with the model group, the oxygen saturation (SatO2) in G1 tolerant group was significantly higher (P<0.05). In the G1 sensitive group, the levels of white blood cell (WBC) count, neutrophil (NEUT) count, hemoglobin (HGB) concentration, hematocrit (HCT), red blood cell distribution width (RDW), platelet (PLT), and creatinine (Cr) significantly increased (P<0.05 or P<0.01), while actual bicarbonate (AB) content significantly decreased (P<0.05), and the brain and lung coefficients were significantly elevated (P<0.05). In addition, pathological section results showed that the brain and lung tissues in the model group, G1 sensitive group, and G1 tolerant group all suffered from significant damage, with no evident differences in the gene expression levels of hypoxia-inducible factor-1 α (HIF-1α) and vascular endothelial growth factor A (VEGFA) in brain tissues among the three groups (P>0.05). Conclusion Compared with standard rats, G1 generation hypoxia-sensitive/tolerant rats exhibit good signs of hypoxia sensitivity/tolerance traits, but further screening and passage are still needed to purify them. [ABSTRACT FROM AUTHOR]

Background: This study aimed to address the increasing prevalence of cesarean section and the importance of evaluating newborn health through arterial blood gas analysis. Its primary objective was to compare the umbilical cord blood gas levels in newborns delivered through different delivery methods. Method: This retrospective descriptive cross-sectional study included singleton pregnancies with a gestational age between 37 and 42 weeks and infants weighing between 2500 and 4000 g. Newborns with an Apgar score of 7 or higher at 1 and 5 min were included. Umbilical cord blood samples were collected from each newborn for blood gas analysis within 60 min after birth. Result: The study included 340 neonates, with 170 born via caesarean section and 170 born through vaginal delivery. No significant differences were observed in Apgar scores between two groups. ABG analysis showed that vaginally born neonates had lower pH (7.24 ± 0.08 vs. 7.27 ± 0.07, P < 0.001), PCO2 (P = 0.015), and HCO3 (P < 0.001). Cesarean section neonates had higher oxygen saturation (P = 0.007) and pressure of oxygen (P < 0.001), and less negative base excess (P < 0.001). In the subgroup analysis, neonates whose mothers received epidural anesthesia had lower pH (7.23 ± 0.07 vs. 7.25 ± 0.08, P = 0.021) and more negative base excess (P = 0.026). Other parameters of ABG did not differ significantly between the groups (P > 0.05). Conclusion: It has been proven that the mode of delivery, whether it is vaginal or cesarean, as well as the administration of epidural anesthesia during vaginal delivery, have a significant impact on newborns at birth. Newborns delivered vaginally exhibit metabolic acidosis compared to those delivered via cesarean section. Although these differences are statistically significant, they do not have a notable clinical significance, as the average values of the evaluated parameters in both groups fall within the normal range. [ABSTRACT FROM AUTHOR]

Background and purpose: The use of multiple tests, including spirometry, arterial blood gas (ABG) analysis and overnight oximetry (OvOx), is highly recommended to monitor the respiratory function of patients with motor neuron disease (MND). In this study, we propose a composite score to simplify the respiratory management of MND patients and better stratify their prognosis. Materials and Methods: We screened the clinical charts of 471 non‐ventilated MND patients referred to the Neuro‐rehabilitation Unit of the San Raffaele Scientific Institute of Milan (January 2001–December 2019), collecting spirometric, ABG and OvOx parameters. To evaluate the prognostic role of each measurement, univariate Cox regression for death/tracheostomy was performed, and the variables associated with survival were selected to design a scoring system. Univariate and multivariate Cox regression analyses were then carried out to evaluate the prognostic role of the score. Finally, results were replicated in an independent cohort from the Turin ALS Center. Results: The study population included 450 patients. Six measurements were found to be significantly associated with survival and were selected to design a scoring system (maximum score = 8 points). Kaplan–Meier analysis showed significant stratification of survival and time to non‐invasive mechanical ventilation adaptation according to score values, and multivariate analysis confirmed the independent effect of the respiratory score on survival of each cohort. Conclusion: Forced vital capacity, ABG and OvOx parameters provide complementary information for the respiratory management and prognosis of MND patients and the combination of these parameters into a single score might help neurologists predict prognosis and guide decisions on the timing of the implementation of different diagnostic or therapeutic approaches. [ABSTRACT FROM AUTHOR]

Objective By screening and passaging G0 generation Wistar rats, we obtained hypoxia-sensitive and hypoxia-tolerant G1 generation rats, and then the differences in hypoxia sensitivity among these rats were preliminarily explored. Methods 200 Wistar rats (half male and half female) were selected as G0 generation and placed in a controlled oxygen concentration system. The hypoxia tolerance time, which refers to the time from placement to near death, was recorded for the G0 generation rats at an oxygen volume fraction of 3%. 30 rats (half male and half female) with the shortest hypoxia tolerance time were selected for mating and passage to obtain G1 generation hypoxia-sensitive rats. Similarly, 30 rats (half male and half female) with the longest hypoxia tolerance time were selected for mating and passage to obtain G1 generation hypoxia-tolerant rats. An additional 24 standard Wistar rats were randomly divided into two groups: a control group and a model group, with 12 rats in each group (half male and half female). The control group was kept in a normoxic environment, while the model group, along with the G1 generation hypoxia-sensitive rats (G1 sensitive group) and G1 generation hypoxia-tolerant rats (G1 tolerant group), were placed in a hypobaric hypoxia chamber (simulating an altitude of 5 000 m). After 12 hours, various indicators, including blood gas, complete blood count, blood biochemistry, pathological sections, and hypoxia-related genes were detected or observed to compare the differences in hypoxia sensitivity among the 4 groups. Results Compared with the G0 generation standard rats, the hypoxia tolerance time of G1 generation rats was significantly prolonged (P0.05).ConclusionCompared with standard rats, G1 generation hypoxia-sensitive/tolerant rats exhibit good signs of hypoxia sensitivity/tolerance traits, but further screening and passage are still needed to purify them.

ObjectivesHuman blood gas stability data is limited to small sample sizes and questionable statistical techniques. We sought to determine the stability of blood gases under room temperature and slushed iced conditions in patients using survival analyses.MethodsWhole blood samples from ∼200 patients were stored in plastic syringes and kept at room temperature (22-24 °C) or in slushed ice (0.1-0.2 °C) before analysis. Arterial and venous pO2 (15-150 mmHg), pCO2 (16-72 mmHg), pH (6.73-7.52), and the CO-oximetry panel [total hemoglobin (5.4-19.3 g/dL), percentages of oxyhemoglobin (O2Hb%, 20-99%), carboxyhemoglobin (COHb, 0.1-5.4%) and methemoglobin (MetHb, 0.2-4.6%)], were measured over 5-time points. The Royal College of Pathologists of Australasia's (RCPA's) criteria determined analyte instability. Survival analyses identified storage times at which 5% of the samples for various analytes became unstable.ResultsCOHb and MetHb were stable up to 3 h in slushed ice and at room temperature; pCO2, pH was stable at room temperature for about 60 min and 3 h in slushed ice. Slushed ice shortened the storage time before pO2 became unstable (from 40 to 20 min), and the instability increased when baseline pO2 was ≥60 mmHg. The storage time for pO2, pCO2, pH, and CO-oximetry, when measured together, were limited by the pO2.ConclusionsWhen assessing pO2 in plastic syringes, samples kept in slushed ice harm their stability. For simplicity's sake, the data support storage times for blood gas and CO-oximetry panels of up to 40 min at room temperature if following RCPA guidelines.

Abstract Objectives N95 or Type II filtering face pieces (FFP2) are often worn during work hours or on public transportation to prevent airborne infection. The aim of this randomized controlled crossover study is to assess the impact of FFP2 induced breathing resistance on pulmonary function, blood gas values and discomfort during walking and stair climbing. Methods N = 16 healthy adults (24.8 ± 2.2 years; 10 females, ) participated. Interventions included (1) six minutes of walking in a 16-meter-long hallway (612 m) and (2) eight minutes of stair climbing in a two-story staircase (420 stairs), both with and without a FFP2 (> 48 h wash-out). Spiroergometric data (Ventilation, breathing frequency, tidal volume, oxygen uptake and carbon dioxide exhalation (primary outcome), end tidal carbon dioxide- and oxygen pressure) and self-reported response (Perceived exertion, dyspnoea and pain) were assessed during activities. Blood gas analysis (capillary carbon dioxide- (pCO2) (primary outcome) and oxygen partial pressure (pO2), pH, lactate and base excess) was measured immediately after cessation of activities. Manipulation effects (FFP2 versus no mask) were tested using repeated measures analyses of variance. Results Analysis showed no effect of FFP2 on pCO2 or other blood-gas parameters but on carbon dioxide exhalation during walking: (mean 1067, SD 209 ml/min) (mean 1908, SD 426 ml/min) (F(15) = 19.5; p

Background. Idiopathic pulmonary arterial hypertension (IPAH) is a severe disease that affects the vessels of the pulmonary circulation and leads to right ventricular failure and death of patients. Indicators of hemodynamics and oxygen transport play central role in the progression and development of the disease. Objective: to evaluate indicators of hemodynamics, oxygen transport. Materials and methods. The study included 124 patients with IPAH. They were divided into two groups: alive patients (group 1) and those who died (group 2). All of them underwent general clinical examinations, a 6-minute walk test, transthoracic and speckle tracking echocardiography, right heart catheterization, blood gas analysis and calculation of hemodynamic parameters. Results. We calculated and compared the right (RVSWI) (19.93 ± 7.84 vs. 16.47 ± 4.67 g·m·m–2, p = 0.009) and left ventricular stroke work index (LVSWI) (39.47 ± 10.53 vs. 35.92 ± 11.19 g·m·m–2, p = 0.036) and their ratio (RVSWI/LVSWI) (0.59 ± 0.16 vs. 0.46 ± ± 0.13, p = 0.008), right (RVPC) (97.00 ± 2.16 vs. 1.82 ± 1.04 g·m, p = 0.001) and left ventricular pump coefficient (LVPC) (5.36 ± 4.84 vs. 4.41 ± 2.15 g·m, p = 0.04) and their ratio (RVPC/LVPC) (0.54 ± 0.19 vs. 0.44 ± 0.11, p = 0.05) in both groups of patients. Also, we found differences in partial pressure of carbon dioxide (PaCO2) of venous blood (34.5 ± 5.1 vs. 40.2 ± 6.9 mm Hg, p = 0.02), partial pressure of oxygen (PaO2) of arterial blood (90.2 ± 15.1 vs. 78.9 ± 11.2 mm Hg; p = 0.01), arteriovenous oxygen difference (A-vO2) (4.5 ± 1.2 vs. 5.0 ± 0.8 ml/dL, p = 0.02) between both groups. Conclusions. RVSWI, LVSWI, RVSWI/LVSWI, RVPC, LVPC, RVPC/LVPC were significantly different between the groups. The use of the above hemodynamic parameters can help in a deeper understanding of the prognosis in IPAH patients. Performance of oxygen transport indicators (PaCO2, PaO2) and A-vO2 in IPAH patients provides a broader understanding of the status and prognosis of this disease.

Abstract Background Bronchopneumonia (BP) in calves potentially causes systemic changes. Objectives To describe metabolic, arterial blood gas, and acid‐base disorders in calves with BP diagnosed by thoracic ultrasound (TUS), Wisconsin score (WISC), and combinations of WISC and TUS. Animals Two hundred thirty‐one dairy preweaned dairy calves from 13 dairy farms. Methods Cross‐sectional study. Each calf sequentially underwent arterial blood gas evaluation, WISC score, venous sampling, and TUS. Calves were grouped based on a single diagnostic method and combination of WISC and 2 TUS cutoffs (≥1 cm; ≥3 cm) as healthy, upper respiratory tract infection, subclinical BP, and clinical BP. Results Oxygenation and acid‐base variables were unaffected. Glucose concentration in TUS‐affected calves was significantly lower (P

Objectives: N95 or Type II filtering face pieces (FFP2) are often worn during work hours or on public transportation to prevent airborne infection. The aim of this randomized controlled crossover study is to assess the impact of FFP2 induced breathing resistance on pulmonary function, blood gas values and discomfort during walking and stair climbing. Methods: N = 16 healthy adults (24.8 ± 2.2 years; 10 females,) participated. Interventions included (1) six minutes of walking in a 16-meter-long hallway (612 m) and (2) eight minutes of stair climbing in a two-story staircase (420 stairs), both with and without a FFP2 (> 48 h wash-out). Spiroergometric data (Ventilation, breathing frequency, tidal volume, oxygen uptake and carbon dioxide exhalation (primary outcome), end tidal carbon dioxide- and oxygen pressure) and self-reported response (Perceived exertion, dyspnoea and pain) were assessed during activities. Blood gas analysis (capillary carbon dioxide- (pCO2) (primary outcome) and oxygen partial pressure (pO2), pH, lactate and base excess) was measured immediately after cessation of activities. Manipulation effects (FFP2 versus no mask) were tested using repeated measures analyses of variance. Results: Analysis showed no effect of FFP2 on pCO2 or other blood-gas parameters but on carbon dioxide exhalation during walking: (mean 1067, SD 209 ml/min) (mean 1908, SD 426 ml/min) (F(15) = 19.5; p < 0.001; ηp2 = 0.566) compared to no mask wearing (mean 1237, SD 173 ml/min; mean 1908, SD 426 ml/min). Ventilation was decreased and dyspnoea was increased by FFP2 during activities. FFP2 led to lower oxygen uptake and lower end tidal oxygen but higher end tidal carbon dioxide during stair climbing. Conclusions: FFP2 decreased ventilation based on slower breathing patterns and led to limitations in pulmonary gas exchange and increased subjective dyspnoea. However, invasive diagnostics revealed no signs of clinically relevant metabolic effects immediately after everyday physical activities. [ABSTRACT FROM AUTHOR]

Blood gas analysis, including parameters like lactate and base excess (BE), is crucial in emergency medicine but less commonly utilized prehospital. This study aims to elucidate the relationship between lactate and BE in various emergencies in a prehospital setting and their prognostic implications. We conducted a retrospective analysis of prehospital emergency patients in Graz, Austria, from October 2015 to November 2020. Our primary aim was to assess the association between BE and lactate. This was assessed using Spearman's rank correlation and fitting a multiple linear regression model with lactate as the outcome, BE as the primary covariate of interest and age, sex, and medical emergency type as confounders. In our analysis population (n=312), lactate and BE levels were inversely correlated (Spearman's ρ, −0.75; p<0.001). From the adjusted multiple linear regression model (n=302), we estimated that a 1 mEq/L increase in BE levels was associated with an average change of −0.35 (95 % CI: −0.39, −0.30; p<0.001) mmol/L in lactate levels. Lactate levels were moderately useful for predicting mortality with notable variations across different emergency types. Our study highlights a significant inverse association between lactate levels and BE in the prehospital setting, underscoring their importance in early assessment and prognosis in emergency care. Additionally, the findings from our secondary aims emphasize the value of lactate in diagnosing acid–base disorders and predicting patient outcomes. Recognizing the nuances in lactate physiology is essential for effective prehospital care in various emergency scenarios. [ABSTRACT FROM AUTHOR]

Background: Cardiopulmonary exercise testing (CPET) assesses exercise capacity and causes of exercise limitation in patients with pulmonary hypertension (PH). At altitude, changes occur in the ventilatory pattern and a decrease in arterial oxygen pressure in healthy; these changes are increased in patients with cardiopulmonary disease. Our objective was to compare the response to exercise and gas exchange between patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) residing at the altitude of Bogotá (2640 m). Methods: All patients performed an incremental CPET with measurement of oxygen consumption (VO2), dead space (VD/VT), ventilatory equivalents (VE/VCO2), and alveolar–arterial oxygen gradient (PA-aO2). X² test and one-way analysis of variance were used for comparisons between PAH and CTEPH. Results: We included 53 patients, 29 with PAH, 24 with CTEPH, and 102 controls as a reference of the normal response to exercise at altitude. CTEPH patients had a higher New York Health Association (NYHA) functional class than PAH (p = 0.037). There were no differences between patients with PAH and CTEPH in hemodynamics and VO2% of predicted (67.8 ± 18.7 vs. 66.0 ± 19.8, p < 0.05), but those with CTEPH had higher dyspnea, VD/VT (0.36 ± 0.09 vs. 0.23 ± 0.9, p < 0.001), VE/VCO2 (45.8 ± 7.1 vs. 39.3 ± 5.6, p < 0.001), and PA-aO2 (19.9 ± 7.6 vs. 13.5 ± 7.6, p < 0.001) than PAH patients. Conclusions: At altitude, patients with PH present severe alterations in gas exchange during exercise. There were no differences in exercise capacity between PAH and CTEPH, but patients with CTEPH had more dyspnea and greater alterations in gas exchange during exercise. CPET made it possible to identify alterations related to the pathophysiology of CTEPH that could explain the functional class and dyspnea in these patients. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study is to measure staff compliance with the local umbilical cord lactate (UCL) sampling guideline and investigate the quality of paired UCG samples at a tertiary maternity unit. Methods: We performed a retrospective consecutive sampling of 100 babies delivered via emergency caesarean section and 50 babies with each of all other guideline‐based indications for UCL sampling born on and before 31 December 2021. Data were extracted from physical and electronic records. Compliance with guideline‐based indications for UCL at birth was measured. The proportion of valid UCG samples was calculated. Samples were considered invalid under the following cases: (i) inadvertently collecting from the same vessel, (ii) switching arterial and venous samples, (iii) collecting from only one vessel or (iv) committing errors during sample collection and handling. Results: Of the samples collected at birth from 321 babies, 280 (87%) had UCL. Small for gestational age and concerns about fetal well‐being in labour were indications associated with poorer compliance, 66% and 78%, respectively. About 99 (44%) babies of 226 babies with UCG performed had valid UCG samples. The most common reasons for invalid samples were collection and handling errors (22%) and inadvertent collection from the same vessel (15%). Conclusions: Generally, compliance with the guidelines is good. However, invalid UCG samples were more frequent than expected. [ABSTRACT FROM AUTHOR]

Background: The goal was to analyze serums of GDM patients and healthy pregnant women using HPLC-MS and preliminarily screen differential metabolites by metabolomics. Method: Sixty pregnant women who underwent elective cesarean section at term in Dongguan Dalang Hospital from January 2023 to April 2023 were selected and divided into the GDM group and healthy pregnancy group. Pre-pregnancy and pregnancy examination information, such as age, BMI, OGTT results, triglyceride, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and other clinical data were collected for statistical analysis. Non-targeted metabolomics of serum from 30 GDM patients and 30 healthy pregnant women were studied by HPLC-MS, and different ions were searched. The structures of differential metabolites were identified by HMDB database. The metabolic pathways of differential metabolites were analyzed by KEGG database. Results: The OGTT result, pCO2, pO2, HCO3, BE, Apgar score, and bilirubin levels in the GDM group were higher than those in the healthy pregnancy group (p < 0.05). However, there were no significant differences in age, triglyceride, total cholesterol, newborn birth weight, newborn birth blood glucose, and blood gas pH between the two groups (all p > 0.05). Using p < 0.05 as the screening standard, 55 differential metabolites were identified in serum, mainly including fatty acyl, carboxylic acids and their derivatives, steroids and their derivatives, ketoacids and their derivatives, and pyrimidine nucleosides, etc., all of which were up-regulated or down-regulated to varying degrees. The 55 metabolites were mainly involved in the metabolism of pyrimidine, pyruvate, alanine, aspartic acid, glutamic acid, and arachidonic acid, glycolysis, and biosynthesis of unsaturated fatty acids. Conclusions: The discovery of these metabolites provides a theoretical basis for an in-depth understanding of GDM pathogenesis. Non-targeted metabonomics analysis of blood metabonomics research technology has shown great potential value in the early diagnosis of obstetric diseases and the study of disease mechanisms. [ABSTRACT FROM AUTHOR]

Background: Bronchopneumonia (BP) in calves potentially causes systemic changes. Objectives: To describe metabolic, arterial blood gas, and acid‐base disorders in calves with BP diagnosed by thoracic ultrasound (TUS), Wisconsin score (WISC), and combinations of WISC and TUS. Animals: Two hundred thirty‐one dairy preweaned dairy calves from 13 dairy farms. Methods: Cross‐sectional study. Each calf sequentially underwent arterial blood gas evaluation, WISC score, venous sampling, and TUS. Calves were grouped based on a single diagnostic method and combination of WISC and 2 TUS cutoffs (≥1 cm; ≥3 cm) as healthy, upper respiratory tract infection, subclinical BP, and clinical BP. Results: Oxygenation and acid‐base variables were unaffected. Glucose concentration in TUS‐affected calves was significantly lower (P <.001) than in healthy calves (median ≥TUS1cm = 5.2 mmol/L 25%‐75% interquartile range [IQR] 4.5‐6.1,

Importance: Deaths due to neonatal calf diarrhea are still one of the most critical problems of cattle breeding worldwide. Determining the parameters that can predict diarrhea-related deaths in calves is especially important in terms of prognosis and treatment strategies for the disease. Objective: The primary purpose of this study was to determine mortality rates and durations, survival status, and predictive prognosis parameters based on vital signs, hematology, and blood gas analyses in neonatal diarrheic calves. Methods: The hospital automation system retrospectively obtained data from 89 neonatal diarrheic calves. Results: It was found that 42.7% (38/89) of the calves brought with the complaint of diarrhea died during hospitalization or after discharge. Short-term and long-term fatalities were a median of 9.25 hours and a median of 51.50 hours, respectively. When the data obtained from this study is evaluated, body temperature (°C), pH, base excess (mmol/L), and sodium bicarbonate (mmol/L) parameters were found to be lower, and hemoglobin (g/dL), hematocrit (%), lactate (mmol/L), chloride (mmol/L), sodium (mmol/L) and anion gap (mmol/L) parameters were found to be higher in dead calves compared to survivors. Accordingly, hypothermia, metabolic acidosis, and dehydration findings were seen as clinical conditions that should be considered. Logistic regression analysis showed that lactate (odds ratio, 1.429) and CI-(odds ratio, 1.232) concentration were significant risk factors associated with death in calves with diarrhea. Conclusions and Relevance: According to the findings obtained from this study, the determination of lactate and Cl- levels can be used as an adjunctive supplementary test in distinguishing calves with diarrhea with a good prognosis. [ABSTRACT FROM AUTHOR]

Abstract Background The continuous exposure of blood to a non-biological surface during extracorporeal membrane oxygenation (ECMO) may lead to progressive thrombus formation in the oxygenator, hemolysis and consequently impaired gas exchange. In most centers oxygenator performance is monitored only on a once daily basis. Carboxyhemoglobin (COHb) is generated upon red cell lysis and is routinely measured with any co-oximetry performed to surveille gas exchange and acid–base homeostasis every couple of hours. This retrospective cohort study aims to evaluate COHb in the arterial blood gas as a novel marker of oxygenator dysfunction and its predictive value for imminent oxygenator change. Results Out of the 484 screened patients on ECMO 89, cumulatively requiring 116 oxygenator changes within 1833 patient days, including 19,692 arterial COHb measurements were analyzed. Higher COHb levels were associated with lower post-oxygenator pO2 (estimate for log(COHb): − 2.176 [95% CI − 2.927, − 1.427], p

Abstract Background Measuring arterial partial pressure of carbon dioxide (PaCO2) is crucial for proper mechanical ventilation, but the current sampling method is invasive. End-tidal carbon dioxide (EtCO2) has been used as a surrogate, which can be measured non-invasively, but its limited accuracy is due to ventilation-perfusion mismatch. This study aimed to develop a non-invasive PaCO2 estimation model using machine learning. Methods This retrospective observational study included pediatric patients (

Background: The continuous exposure of blood to a non-biological surface during extracorporeal membrane oxygenation (ECMO) may lead to progressive thrombus formation in the oxygenator, hemolysis and consequently impaired gas exchange. In most centers oxygenator performance is monitored only on a once daily basis. Carboxyhemoglobin (COHb) is generated upon red cell lysis and is routinely measured with any co-oximetry performed to surveille gas exchange and acid–base homeostasis every couple of hours. This retrospective cohort study aims to evaluate COHb in the arterial blood gas as a novel marker of oxygenator dysfunction and its predictive value for imminent oxygenator change. Results: Out of the 484 screened patients on ECMO 89, cumulatively requiring 116 oxygenator changes within 1833 patient days, including 19,692 arterial COHb measurements were analyzed. Higher COHb levels were associated with lower post-oxygenator pO2 (estimate for log(COHb): − 2.176 [95% CI − 2.927, − 1.427], p < 0.0001) and with a shorter time to oxygenator change (estimate for log(COHb): − 67.895 [95% CI − 74.209, − 61.542] hours, p < 0.0001). COHb was predictive of oxygenator change within 6 h (estimate for log(COHb): 5.027 [95% CI 1.670, 15.126], p = 0.004). Conclusion: COHb correlates with oxygenator performance and can be predictive of imminent oxygenator change. Therefore, longitudinal measurements of COHb in clinical routine might be a cheap and more granular candidate for ECMO surveillance that should be further analyzed in a controlled prospective trial design. [ABSTRACT FROM AUTHOR]

To indicate predictors of witnessed hypothermic cardiac arrest. We conducted a retrospective analysis of 182 patients with severe accidental hypothermia (i.e., with core body temperature of ≤28 °C) who presented with preserved spontaneous circulation at first contact with medical services. We divided the study population into two groups: patients who suffered hypothermic cardiac arrest (HCA) at any time between encounter with medical service and restoration of normothermia, and those who did not sustain HCA. The analyzed outcome was the occurrence of cardiac arrest prior to achieving normothermia. Hemodynamic and biochemical parameters were analyzed with regard to their association with the outcome. Fifty-two (29%) patients suffered HCA. In a univariable analysis, four variables were significantly associated with the outcome, namely heart rate (p < 0.001), systolic blood pressure (p = 0.03), ventricular arrhythmia (p = 0.001), and arterial oxygen partial pressure (p = 0.002). In the multivariable logistic regression the best model predicting HCA included heart rate, PaO 2 , and Base Excess (AUROC = 0.78). In prehospital settings, when blood gas analysis is not available, other multivariable model including heart rate and occurrence of ventricular arrhythmia (AUROC = 0.74) can be used. In this study population, threshold values of heart rate of 43/min, temperature-corrected PaO 2 of 72 mmHg, and uncorrected PaO 2 of 109 mmHg, presented satisfactory sensitivity and specificity for HCA prediction. In patients with severe accidental hypothermia, the occurrence of HCA is associated with a lower heart rate, hypoxemia, ventricular arrhythmia, lower BE, and lower blood pressure. These parameters can be helpful in the early selection of high-risk patients and their allocation to extracorporeal rewarming facilities. [ABSTRACT FROM AUTHOR]

Polyoxotungstate nanoclusters have recently emerged as promising contrast agents for computed tomography (CT). In order to evaluate their clinical potential, in this study, we evaluated the in vitro CT imaging properties, potential toxic effects in vivo, and tissue distribution of monolacunary Wells–Dawson polyoxometalate, α2-K10P2W17O61.20H2O (mono-WD POM). Mono-WD POM showed superior X-ray attenuation compared to other tungsten-containing nanoclusters (its parent WD-POM and Keggin POM) and the standard iodine-based contrast agent (iohexol). The calculated X-ray attenuation linear slope for mono-WD POM was significantly higher compared to parent WD-POM, Keggin POM, and iohexol (5.97 ± 0.14 vs. 4.84 ± 0.05, 4.55 ± 0.16, and 4.30 ± 0.09, respectively). Acute oral (maximum-administered dose (MAD) = 960 mg/kg) and intravenous administration (1/10, 1/5, and 1/3 MAD) of mono-WD POM did not induce unexpected changes in rats' general habits or mortality. Results of blood gas analysis, CO-oximetry status, and the levels of electrolytes, glucose, lactate, creatinine, and BUN demonstrated a dose-dependent tendency 14 days after intravenous administration of mono-WD POM. The most significant differences compared to the control were observed for 1/3 MAD, being approximately seventy times higher than the typically used dose (0.015 mmol W/kg) of tungsten-based contrast agents. The highest tungsten deposition was found in the kidney (1/3 MAD—0.67 ± 0.12; 1/5 MAD—0.59 ± 0.07; 1/10 MAD—0.54 ± 0.05), which corresponded to detected morphological irregularities, electrolyte imbalance, and increased BUN levels. [ABSTRACT FROM AUTHOR]

BACKGROUND: Infants with hypoxic-ischemic encephalopathy are often treated with therapeutic hypothermia and high-frequency ventilation. Fluctuations in PaCO2 during therapeutic hypothermia are associated with poor neurodevelopmental outcomes. Transcutaneous CO2 monitors offer a noninvasive estimate of PaCO2 represented by transcutaneously measured partial pressure of carbon dioxide (PtcCO2). We aimed to assess the precision between PtcCO2 and PaCO2 values in neonates undergoing therapeutic hypothermia. METHODS: This was a retrospective chart review of 10 neonates who underwent therapeutic hypothermia requiring respiratory support over 2 y. A range of 2--27 simultaneous PaCO2 and PaCO2 pairs of measurements per neonate were analyzed via linear mixed models and a Bland-Altman plot for multiple observations per neonate. RESULTS: A linear mixed-effect model demonstrated that PaCO2 and PaCO2 (controlling for sex) were similar. The 95% CI of the mean difference ranged from 22.3 to 5.7 mm Hg (P 5 .41). However, precision was poor as the PaCO2 ranged from > 18 mm Hg to < 13 mm Hg than PaCO2 values for 95% of observations. CONCLUSIONS: The neonates' PaCO2 was as much as 18 mm Hg higher to 13 mm Hg lower than the PaCO295% of the time. Transcutaneous CO2 monitoring may not be a good trending tool, nor is it appropriate for estimating PaCO2 in patients undergoing therapeutic hypothermia. [ABSTRACT FROM AUTHOR]

Background: Measuring arterial partial pressure of carbon dioxide (PaCO2) is crucial for proper mechanical ventilation, but the current sampling method is invasive. End-tidal carbon dioxide (EtCO2) has been used as a surrogate, which can be measured non-invasively, but its limited accuracy is due to ventilation-perfusion mismatch. This study aimed to develop a non-invasive PaCO2 estimation model using machine learning. Methods: This retrospective observational study included pediatric patients (< 18 years) admitted to the pediatric intensive care unit of a tertiary children’s hospital and received mechanical ventilation between January 2021 and June 2022. Clinical information, including mechanical ventilation parameters and laboratory test results, was used for machine learning. Linear regression, multilayer perceptron, and extreme gradient boosting were implemented. The dataset was divided into 7:3 ratios for training and testing. Model performance was assessed using the R2 value. Results: We analyzed total 2,427 measurements from 32 patients. The median (interquartile range) age was 16 (12−19.5) months, and 74.1% were female. The PaCO2 and EtCO2 were 63 (50−83) mmHg and 43 (35−54) mmHg, respectively. A significant discrepancy of 19 (12–31) mmHg existed between EtCO2 and the measured PaCO2. The R2 coefficient of determination for the developed models was 0.799 for the linear regression model, 0.851 for the multilayer perceptron model, and 0.877 for the extreme gradient boosting model. The correlations with PaCO2 were higher in all three models compared to EtCO2. Conclusions: We developed machine learning models to non-invasively estimate PaCO2 in pediatric patients receiving mechanical ventilation, demonstrating acceptable performance. Further research is needed to improve reliability and external validation. [ABSTRACT FROM AUTHOR]

OBJECTIVE: It is known that providing recanalization alone in large vessel occlusions is not sufficient to provide a good 90-day clinical outcome. It is advocated that neuroprotection should be increased before endovascular treatment and that the penumbra should be protected from reperfusion damage after recanalization. However, the effects of blood gas parameters before and after mechanical thrombectomy on clinical outcomes are not clear. The objective of this study is to assess the effectiveness of serial blood gas measures in accurately predicting futile recanalization at an early stage. PATIENTS AND METHODS: This study is a multicenter inquiry that collected data in a prospective manner and analyzed it retrospectively. Patients with a 2b-3 thrombolysis in cerebral infarction (TICI) score after mechanical thrombectomy for recanalization were consecutively analyzed from July 2022 to March 2023. Arterial blood gas parameters, including pH, oxygen saturation (SaO2), partial carbon dioxide pressure (PaCO2), partial oxygen pressure (PaO2), lactate, and bicarbonate (HCO3), were measured at four time points: before mechanical thrombectomy treatment (preoperative), immediately after recanalization (postoperative 1st), during the 3rd hour (postoperative 3rd), and at the 5th hour (postoperative 5th). The patients were categorized into groups based on their modified Rankin Scale (mRS) scores. RESULTS: The study included 136 patients with an average age of 69.71±11.22. The postoperative 1st-hour SaO2 values were lower in the mRS 3-6 group (p=0.038). The postoperative pH and lactate mean were greater in the mRS 3-6 group than in the 0-2 group (p=0.038 and 0.018, respectively). In logistic regression, a unit rise in lactate increased poor functional outcomes 1,632 times (p=0.024). Early neurological recovery was associated with decreased postoperative 3rd-hour lactate (p=0.014). The mean postoperative PaO2 (average of 1, 2, 3 PaO2) was higher in those with symptomatic cerebral bleeding (p=0.044). CONCLUSIONS: Monitoring lactate and pH levels in AIS patients who have had mechanical recanalization can be utilized to predict mortality and morbidity, especially in the first five hours after the procedure. [ABSTRACT FROM AUTHOR]

There is limited information on the influence of collecting small amounts of blood on the quality of blood gas analysis. Therefore, the purpose of this study was to investigate the effects of different degrees of underfilling of syringes on test results of venous blood gas analysis. Venous blood was collected by venipuncture from 19 healthcare workers in three 1.0 mL syringes for blood gas analysis, by manually aspirating different volumes of blood (i.e., 1.0, 0.5 and 0.25 mL). Routine blood gas analysis was then immediately performed with GEM Premier 5,000. The results of the two underfilled syringes were compared with those of the reference syringe filled with appropriate blood volume. The values of most assayed parameters did not differ significantly in the two underfilled syringes. Statistically significant variations were found for lactate, hematocrit and total hemoglobin, the values of which gradually increased as the fill volume diminished, as well as for sodium concentration, which decreased in both insufficiently filled blood gas syringes. The bias was clinically meaningful for lactate in syringe filled with 0.25 mL of blood, and for hematocrit, total hemoglobin and sodium in both syringes containing 0.5 and 0.25 mL of blood. Collection of smaller volumes of venous blood than the specified filling volume in blood gas syringes may have an effect on the quality of some test results, namely lactate, hematocrit, total hemoglobin and sodium. Specific indications must be given for standardizing the volume of blood to be collected within these syringes. [ABSTRACT FROM AUTHOR]

ABSTRACT Introduction: hemorrhagic shock is a significant cause of trauma-related deaths in Brazil and worldwide. This study aims to compare BE and lactate values at ICU admission and twenty-four hours after in identifying tissue hypoperfusion and mortality. Methods: examines a historical cohort of trauma patients over eitheen years old submittet to damage control resuscitation approch upon hospital admission and were then admitted to the ICU. We collected and analyzed ISS, mechanism and type of trauma, need for renal replacement therapy, massive transfusion. BE, lactate, pH, bicarbonate at ICU admission and twenty-four hours later, and mortality data. The patients were grouped based on their BE values (≥-6 and

Objective To investigate the effect of using pulmonary surfactant (PS) during different time periods of mechanical ventilation in the treatment of neonatal respiratory distress syndrome (NRDS) on blood gas and lung function indicators in children. Methods A total of 80 children with NRDS who received treatment at Neonatal Intensive Care Unit, Nanjing Jiangbei Hospital from February 2021 to February 2023 were selected and divided into observation group A, observation group B, observation group C and control group randomly (n=20, each). All the children received routine mechanical ventilation and comprehensive treatment for 72 hours. In the observation group A, B and C, the same dose of PS (70 mg/kg) was slowly injected into the intake pipe intubation within 0.5 h, 2-4 h and 4-6 h after mechanical ventilation, respectively. The blood gas indexes, lung function indexes, clinical efficacy and complications of the four groups before mechanical ventilation and 6 hours after PS treatment were compared. Results The improvement of blood gas indexes (PaO2, PaCO2, pH value) in the observation group A, B and C were significantly better than those in the control group at 6 h after PS (P＜0.05). The pulmonary function indexes, spontaneous breathing times, lung compliance and blood oxygen saturation recovery time of children in observation group A, B and C after using PS were prolonged in turn, but they were significantly better than those in control group (P＜0.05). The total efficiency of the observation group was significantly higher than that of the control group (98.33% vs 80.00%, χ2=5.760, P=0.016). The incidence of complications in the observation group during treatment was significantly lower than that in the control group (3.33% vs 25.00%, χ2=6.314, P=0.012). Conclusion The combination of mechanical ventilation and PS treatment can improve the prognosis of children with NRDS. The earlier the use of PS, the better the effect.

Abstract Objective To identify primary factors contributing to hemodialysis-related headache (HRH) in maintenance hemodialysis (MHD) patients. Methods Adult outpatients receiving MHD were prospectively enrolled from a hemodialysis (HD) center of a tertiary hospital in China. Twelve dialysis sessions were successively monitored for each patient. HRH is defined as having at least three headache episodes that begin during HD and resolve within 72 h of HD session completion. Blood gas analysis during headache episodes and body composition analysis after dialysis were conducted. Hour-to-hour vital sign variability during dialysis was assessed using the metric of average real variability (ARV). Multivariable logistic regression analysis was conducted to explore the factors triggering HRH. Results A total of 95 Chinese MHD patients were enrolled, with 92 patients (60.9% were males) included in the final analysis. The mean age of the 92 patients was 59.3 ± 17.5 years, and the median dialysis vintage was 27.1 (12–46.2) months. Among them, 12 patients (13%) complained of 42 headache attacks, and eight (8.7%) were diagnosed with HRH. For eight patients with HRH, headache occurred 100.3 ± 69.5 min after the start of dialysis, with a mean VAS score of 4.3 ± 1 points. The quality of headaches was dull (six patients), pulsating (one patient), or stabbing pain (one patient); all the headaches were bilateral, with one having concomitant vomiting. The intradialysis headache duration and the whole headache duration were 98.8 ± 68.1 and 120 (65–217.5) minutes, respectively. Younger age (OR = 0.844, 95% CI 0.719–0.991, p = 0.039), decreased blood sodium level (OR = 0.309 in the range of 133–142 mmol/L, 95% CI 0.111–0.856, p = 0.024), increased ARV of intradialysis systolic blood pressure (OR = 3.067, 95% CI 1.006–9.348, p = 0.049) and ratio of overhydration to dry weight (OR = 1.990, 95% CI 1.033–3.832, p = 0.040) were found to be independent risk factors for HRH. Conclusions This study suggested a significant attribution of blood sodium, hydration status and blood pressure variability to HRH.

Abstract Chronic obstructive pulmonary disease can lead to acute hypercapnic respiratory failure (AHRF), often treated using noninvasive ventilation (NIV). Emerging research suggests the potential utility of high flow nasal cannula (HFNC) for AHRF. This systematic review and meta‐analysis aimed to determine the effect of HFNC versus NIV on AHRF management. A search of electronic databases (CINAHL, MEDLINE, and Academic Search Complete), web sources, and trial registries was last conducted on 9 February 2023. Quality and risk of bias assessments were conducted. Meta‐analyses were used to synthesise data. Seven randomised controlled trials were included. No statistically significant differences between HFNC and NIV were found within the following outcomes of interest: (i) correction of pCO2: standardised mean difference (SMD) = −0.16, 95% confidence interval (CI) (−0.34 to 0.02), p = 0.08; (ii) correction of pH: SMD = −0.05, 95% CI (−0.25 to 0.14), p = 0.59; (iii) correction of pO2: SMD = −0.15, 95% CI (−0.40 to 0.09), p = 0.22; (iv) intubation rates: risk ratio (RR) = 0.87, 95% CI (0.41 to 1.82), p = 0.71; (v) mortality rates: RR = 0.85, 95% CI (0.47 to 1.56), p = 0.61; and (vi) treatment switch: RR = 1.30, 95% CI (0.43 to 3.94), p = 0.64. More controlled trials with large sample sizes are required to investigate the management of AHRF of various aetiologies. HFNC may be used as a final exhaustive measure for COPD‐related AHRF where NIV is not tolerated, and when it is not clinically indicated to extend to endotracheal intubation.

Heat stress (HS) is one of the key factors affecting an animal’s immune system and productivity, as a result of a physiological reaction combined with environmental factors. This study examined the short-term effects of heat stress on cow behavior, as recorded by innovative technologies, and its impact on blood gas parameters, using 56 of the 1070 cows clinically evaluated during the second and subsequent lactations within the first 30 days postpartum. Throughout the experiment (from 4 June 2024 until 1 July 2024), cow behavior parameters (rumination time min/d. (RT), body temperature (°C), reticulorumen pH, water consumption (L/day), cow activity (h/day)) were monitored using specialized SmaXtec boluses and employing a blood gas analyzer (Siemens Healthineers, 1200 Courtneypark Dr E Mississauga, L5T 1P2, Canada). During the study period, the temperature–humidity index (THI), based on ambient temperature and humidity, was recorded and used to calculate THI and to categorize the data into four THI classes as follows: 1—THI 60–63 (4 June 2024–12 June 2024); 2—THI 65–69 (13 June 2024–18 June 2024); 3—THI 73–75 (19 June 2024–25 June 2024); and 4—THI 73–78 (26 June 2024–1 July 2024). The results showed that heat stress significantly reduced rumination time by up to 70% in cows within the highest THI class (73 to 78) and increased body temperature by 2%. It also caused a 12.6% decrease in partial carbon dioxide pressure (pCO2) and a 32% increase in partial oxygen pressure (pO2), also decreasing plasma sodium by 1.36% and potassium by 6%, while increasing chloride by 3%. The findings underscore the critical need for continuous monitoring, early detection, and proactive management to mitigate the adverse impacts of heat stress on dairy cow health and productivity. Recommendations include the use of advanced monitoring technologies and specific blood gas parameter tracking to detect the early signs of heat stress and implement more timely interventions.

Background: Idiopathic intracranial hypertension is characterized by increased intracranial pressure with unidentified pathology. Despite its use as the first-line treatment, data on acetazolamide's effectiveness and safety in pediatric idiopathic intracranial hypertension is sparse. This study's objective was to assess those issues and the need for routine blood gas monitoring during treatment. Methods: Retrospective observational cohort study, based on multicenter computerized medical charts of pediatric patients with idiopathic intracranial hypertension diagnosed between 2007–2018 in three medical centers serving one metropolitan area (an estimated population of 400,000 children). Clinical and laboratory data of children up to 18 years old, fulfilling the Friedman criteria and taking acetazolamide, were collected and analyzed. Results: Sixty-eight patients were included with a mean acetazolamide treatment duration of 8.5 months and a median maximal dose 18 mg/kg/d. Sixty-two children had mild (76%), moderate (13%), or severe (1.5%) metabolic acidosis. At least one adverse effect (neurologic, gastrointestinal, renal) was recorded among 27% of patients. No significant difference was found between the mean pH of children with or without clinical adverse effects (p = 0.35). No correlation was found between laboratory acidosis and adverse effect severity (p = 0.3), or between median acetazolamide dose and acidosis level (p = 0.57). Conclusions: Although laboratory finding of metabolic acidosis is common among patients with idiopathic intracranial hypertension treated with acetazolamide, it is not correlated with clinics. Therefore, we recommend sending blood tests during acetazolamide treatment based on clinical judgment. [ABSTRACT FROM AUTHOR]

Simple Summary: Diagnosis of respiratory diseases uses a variety of tools in addition to signalment and clinical signs, including physical examination, blood tests, and diagnostic imaging. Until now, studies have been conducted on the relationship between specific respiratory diseases and physical examination and blood test findings, but there have been no reports on these test findings for respiratory diseases as a whole. This study aimed to investigate the association of physical examinations and blood tests with canine respiratory diseases and to compare the examination findings in the chronic and acute phases. Significant associations were observed with various items mainly in lung diseases, such as increased respiratory rate, decreased oxygen saturation, and increased C-reactive protein in both chronic and acute phases. Blood gas analysis showed that respiratory alkalosis was most prevalent in the chronic phase, whereas respiratory acidosis was most prevalent in the acute phase. The results obtained in this study demonstrate that these testing tools are useful for diagnosis and monitoring or treatment responses in respiratory diseases. This study aimed to investigate the association of respiratory rate (RR), oxygen saturation (SpO2), and blood findings with respiratory disease in dogs and to compare the examination findings in the chronic and acute phases. Dogs that visited a veterinary referral hospital with respiratory symptoms were classified into the chronic disease group (GC), and those that visited the emergency veterinary hospital were classified into the acute disease group (GA). In total, 704 and 682 dogs were included in GC and GA, respectively. The RR and SpO2 were significantly higher and lower, respectively, in patients with lung disease compared to other disease sites in both groups. White blood cell counts were significantly increased in patients with lung and pleural diseases in both groups. Respiratory alkalosis and respiratory acidosis were most common in GC and GA, respectively. The C-reactive protein levels were elevated in both groups, primarily in patients with lung disease. Associations between the results of several tests for understanding and diagnosing respiratory conditions and diseases were recognized, and differences in the trends of the chronic and acute phases were clarified. These tools may be used as adjuncts to other tests for the diagnosis and monitoring of treatment responses. [ABSTRACT FROM AUTHOR]

Objective: To identify primary factors contributing to hemodialysis-related headache (HRH) in maintenance hemodialysis (MHD) patients. Methods: Adult outpatients receiving MHD were prospectively enrolled from a hemodialysis (HD) center of a tertiary hospital in China. Twelve dialysis sessions were successively monitored for each patient. HRH is defined as having at least three headache episodes that begin during HD and resolve within 72 h of HD session completion. Blood gas analysis during headache episodes and body composition analysis after dialysis were conducted. Hour-to-hour vital sign variability during dialysis was assessed using the metric of average real variability (ARV). Multivariable logistic regression analysis was conducted to explore the factors triggering HRH. Results: A total of 95 Chinese MHD patients were enrolled, with 92 patients (60.9% were males) included in the final analysis. The mean age of the 92 patients was 59.3 ± 17.5 years, and the median dialysis vintage was 27.1 (12–46.2) months. Among them, 12 patients (13%) complained of 42 headache attacks, and eight (8.7%) were diagnosed with HRH. For eight patients with HRH, headache occurred 100.3 ± 69.5 min after the start of dialysis, with a mean VAS score of 4.3 ± 1 points. The quality of headaches was dull (six patients), pulsating (one patient), or stabbing pain (one patient); all the headaches were bilateral, with one having concomitant vomiting. The intradialysis headache duration and the whole headache duration were 98.8 ± 68.1 and 120 (65–217.5) minutes, respectively. Younger age (OR = 0.844, 95% CI 0.719–0.991, p = 0.039), decreased blood sodium level (OR = 0.309 in the range of 133–142 mmol/L, 95% CI 0.111–0.856, p = 0.024), increased ARV of intradialysis systolic blood pressure (OR = 3.067, 95% CI 1.006–9.348, p = 0.049) and ratio of overhydration to dry weight (OR = 1.990, 95% CI 1.033–3.832, p = 0.040) were found to be independent risk factors for HRH. Conclusions: This study suggested a significant attribution of blood sodium, hydration status and blood pressure variability to HRH. [ABSTRACT FROM AUTHOR]

Chronic obstructive pulmonary disease can lead to acute hypercapnic respiratory failure (AHRF), often treated using noninvasive ventilation (NIV). Emerging research suggests the potential utility of high flow nasal cannula (HFNC) for AHRF. This systematic review and meta‐analysis aimed to determine the effect of HFNC versus NIV on AHRF management. A search of electronic databases (CINAHL, MEDLINE, and Academic Search Complete), web sources, and trial registries was last conducted on 9 February 2023. Quality and risk of bias assessments were conducted. Meta‐analyses were used to synthesise data. Seven randomised controlled trials were included. No statistically significant differences between HFNC and NIV were found within the following outcomes of interest: (i) correction of pCO2: standardised mean difference (SMD) = −0.16, 95% confidence interval (CI) (−0.34 to 0.02), p = 0.08; (ii) correction of pH: SMD = −0.05, 95% CI (−0.25 to 0.14), p = 0.59; (iii) correction of pO2: SMD = −0.15, 95% CI (−0.40 to 0.09), p = 0.22; (iv) intubation rates: risk ratio (RR) = 0.87, 95% CI (0.41 to 1.82), p = 0.71; (v) mortality rates: RR = 0.85, 95% CI (0.47 to 1.56), p = 0.61; and (vi) treatment switch: RR = 1.30, 95% CI (0.43 to 3.94), p = 0.64. More controlled trials with large sample sizes are required to investigate the management of AHRF of various aetiologies. HFNC may be used as a final exhaustive measure for COPD‐related AHRF where NIV is not tolerated, and when it is not clinically indicated to extend to endotracheal intubation. [ABSTRACT FROM AUTHOR]

Background: Hyperkalaemia is managed in the emergency department (ED) following measurement of potassium results by blood gas analysers (BGA) or laboratory analysers (LAB). Aims: To determine the prevalence of clinically significant differences between BGA and LAB potassium results and the impact on ED hyperkalaemia management. Methods: Retrospective analysis of time‐matched ED BGA and LAB potassium samples from 2019 to 2020 (taken within 15 min, one or both results ≥6.0 mmol/L). Mean differences and 95% limits of agreement (LoA) were determined for pairs with one or both results ≥6.0 mmol/L and a separate 500 consecutive sample pairs. Results: Four hundred eighty‐eight matched BGA and LAB samples met the inclusion criteria. Of these, 201 (41.2%) differed by ≤0.5 mmol/L, 169 (34.6%) included a haemolysed LAB sample, and 12 (2.5%) had an unreportable BGA sample. One hundred six (21.7%) pairs differed by >0.5 mmol/L, and 60/106 (57%) had normal LAB potassium results, but BGA indicated moderate/severe hyperkalaemia (two of these pairs received hyperkalaemia treatment). Of patients with a haemolysed LAB sample, or where pairs differed by >0.5 mmol, 48 were treated with insulin and five (10.4%) experienced hypoglycaemia. Mean differences and LoA for pairs with LAB results <6.0 mmol/L but BGA ≥6.0 mmol/L demonstrated unacceptable agreement, with 18 (25.7%) BGA results exceeding 8.0 mmol/L. Conclusions: Potentially significant discordance may occur between BGA and LAB potassium results. Clinicians need to be aware of factors impacting both analytical methods' accuracy (such as poor venepuncture or sample handling, (K) EDTA interference) and undetectable haemolysis with BGA measurements. We recommend BGA hyperkalaemia be confirmed with LAB results using a non‐haemolysed sample where time permits. [ABSTRACT FROM AUTHOR]

BACKGROUND: Emergency patients with sepsis or septic shock are at high risk of death. Despite increasing attention to microhemodynamics, the clinical use of advanced microcirculatory assessment is limited due to its shortcomings. Since blood gas analysis is a widely used technique reflecting global oxygen supply and consumption, it may serve as a surrogate for microcirculation monitoring in septic treatment. METHODS: We performed a search using PubMed, Web of Science, and Google scholar. The studies and reviews that were most relevant to septic microcirculatory dysfunctions and blood gas parameters were identified and included. RESULTS: Based on the pathophysiology of oxygen metabolism, the included articles provided a general overview of employing blood gas analysis and its derived set of indicators for microhemodynamic monitoring in septic care. Notwithstanding flaws, several parameters are linked to changes in the microcirculation. A comprehensive interpretation of blood gas parameters can be used in order to achieve hemodynamic optimization in septic patients. CONCLUSION: Blood gas analysis in combination with clinical performance is a reliable alternative for microcirculatory assessments. A deep understanding of oxygen metabolism in septic settings may help emergency physicians to better use blood gas analysis in the evaluation and treatment of sepsis and septic shock. [ABSTRACT FROM AUTHOR]

To investigate the impact of non-invasive sequential ventilation treatment based on the use of an invasive ventilator on the arterial blood gas and inflammatory stress reaction in patients with severe pneumonia with respiratory failure. Ninety patients with severe pneumonia and respiratory failure were equally separated into two groups via a random number table: a conventional treatment group (subjected to invasive mechanical ventilation) and a study group (subjected to invasive mechanical ventilation and noninvasive sequential ventilation treatment). We compared the two groups with respect to several key parameters before and after treatment, including mechanical ventilation time, invasive ventilation time, intensive care unit (ICU) stay, hospital stay, blood gas analysis indicators and the levels of inflammatory factors in the serum. We also compared the two groups with regards to complications. Mechanical ventilation time, invasive ventilation time, ICU stay and hospital stay in the study group were significantly shorter than that in the conventional treatment group (p < 0.05). Arterial Oxygen Saturation (SaO2), Partial Pressure of Oxygen (PaO2) and pH in the study group after intervention were significantly higher than those in the conventional treatment group after intervention (p< 0.05). Following intervention, white blood cell (WBC), serum c-reactive protein (CRP) and serum interleukin-6 (IL-6) were significantly lower than those in the conventional treatment group (p < 0.05). The total incidence of complications in the study group was markedly lower than in the conventional treatment group. Non-invasive sequential ventilation therapy based on an invasive ventilator had a significant treatment impact on patients with severe pneumonia and respiratory failure. This treatment effectively reduced the average treatment time, improved blood gas analysis indicators and reduced inflammatory stress, thus reducing the incidence of complications. [ABSTRACT FROM AUTHOR]

The existing coverage criteria for noninvasive ventilation (NIV) do not recognize the benefits of early initiation of NIV for those with thoracic restrictive disorders and do not address the unique needs for daytime support as the patients progress to ventilator dependence. This document summarizes the work of the thoracic restrictive disorder Technical Expert Panel working group. The most pressing current coverage barriers identified were: (1) delays in implementing NIV treatment; (2) lack of coverage for many nonprogressive neuromuscular diseases; and (3) lack of clear policy indications for home mechanical ventilation (HMV) support in thoracic restrictive disorders. To best address these issues, we make the following key recommendations: (1) given the need to encourage early initiation of NIV with bilevel positive airway pressure devices, we recommend that symptoms be considered as a reason to initiate therapy even at mildly reduced FVCs; (2) broaden CO2 measurements to include surrogates such as transcutaneous, end-tidal, or venous blood gas; (3) expand the diagnostic category to include phrenic nerve injuries and disorders of central drive; (4) allow a bilevel positive airway pressure device to be advanced to an HMV when the vital capacity is < 30% or to address severe daytime respiratory symptoms; and (5) provide additional HMV when the patient is ventilator dependent with use > 18 h per day. Adoption of these proposed recommendations would result in the right device, at the right time, for the right type of patients with thoracic restrictive disorders.

Wide fluctuations in partial pressure of carbon dioxide (PaCO2) can potentially be associated with neurological and lung injury in neonates. Blood gas measurement is the gold standard for assessing gas exchange but is intermittent, invasive, and contributes to iatrogenic blood loss. Non-invasive carbon dioxide (CO2) monitoring has become ubiquitous in anesthesia and critical care and is being increasingly used in neonates. Two common methods of non-invasive CO2 monitoring are end-tidal and transcutaneous. A colorimetric CO2 detector (a modified end-tidal CO2 detector) is recommended by the International Liaison Committee on Resuscitation (ILCOR) and the American Academy of Pediatrics to confirm endotracheal tube placement. Continuous CO2 monitoring is helpful in trending PaCO2 in critically ill neonates on respiratory support and can potentially lead to early detection and minimization of fluctuations in PaCO2. This review includes a description of the various types of CO2 monitoring and their applications, benefits, and limitations in neonates.

Background: Cardiopulmonary exercise testing (CPET) assesses exercise capacity and causes of exercise limitation in patients with pulmonary hypertension (PH). At altitude, changes occur in the ventilatory pattern and a decrease in arterial oxygen pressure in healthy; these changes are increased in patients with cardiopulmonary disease. Our objective was to compare the response to exercise and gas exchange between patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) residing at the altitude of Bogotá (2640 m). Methods: All patients performed an incremental CPET with measurement of oxygen consumption (VO2), dead space (VD/VT), ventilatory equivalents (VE/VCO2), and alveolar–arterial oxygen gradient (PA-aO2). X2 test and one-way analysis of variance were used for comparisons between PAH and CTEPH. Results: We included 53 patients, 29 with PAH, 24 with CTEPH, and 102 controls as a reference of the normal response to exercise at altitude. CTEPH patients had a higher New York Health Association (NYHA) functional class than PAH (p = 0.037). There were no differences between patients with PAH and CTEPH in hemodynamics and VO2% of predicted (67.8 ± 18.7 vs. 66.0 ± 19.8, p < 0.05), but those with CTEPH had higher dyspnea, VD/VT (0.36 ± 0.09 vs. 0.23 ± 0.9, p < 0.001), VE/VCO2 (45.8 ± 7.1 vs. 39.3 ± 5.6, p < 0.001), and PA-aO2 (19.9 ± 7.6 vs. 13.5 ± 7.6, p < 0.001) than PAH patients. Conclusions: At altitude, patients with PH present severe alterations in gas exchange during exercise. There were no differences in exercise capacity between PAH and CTEPH, but patients with CTEPH had more dyspnea and greater alterations in gas exchange during exercise. CPET made it possible to identify alterations related to the pathophysiology of CTEPH that could explain the functional class and dyspnea in these patients.

BackgroundThe neonatal resuscitation program (NRP) recommends interrupted chest compressions (CCs) with ventilation in the severely bradycardic neonate. The conventional 3:1 compression-to-ventilation (C:V) resuscitation provides 90 CCs/min, significantly lower than the intrinsic newborn heart rate (120-160 beats/min). Continuous CC with asynchronous ventilation (CCCaV) may improve the success of return of spontaneous circulation (ROSC).MethodsTwenty-two near-term fetal lambs were randomized to interrupted 3:1 C:V (90 CCs + 30 breaths/min) or CCCaV (120 CCs + 30 breaths/min). Asphyxiation was induced by cord occlusion. After 5 min of asystole, resuscitation began following NRP guidelines. The first dose of epinephrine was given at 6 min. Invasive arterial blood pressure and left carotid blood flow were continuously measured. Serial arterial blood gases were collected.ResultsBaseline characteristics between groups were similar. Rate of and time to ROSC was similar between groups. CCCaV was associated with a higher PaO2 (partial oxygen tension) (22 ± 5.3 vs. 15 ± 3.5 mmHg, p