Arterial Blood Gas Analysis Research Articles

TOXIC ALCOHOL POISONING: A CASE REPORT

During the COVID-19 pandemic, toxic alcohol poisoning, notably from methanol, has emerged as a significant concern due to increased consumption of illicit liquor amidst lockdown restrictions. We present a case of a middle-aged man who developed altered consciousness, metabolic acidosis, and shock two days after ingesting hospital spirit. Although initial qualitative tests only detected ethanol, subsequent MRI findings showed classical signs of methanol poisoning, including basal ganglia abnormalities. Prompt management with dialysis, ventilatory support, and adjunctive therapy successfully addressed the acute phase despite the patient remaining delirious for seven days. This case underscores the importance of considering methanol toxicity even in the absence of direct evidence, necessitating comprehensive diagnostic approaches. Awareness and incorporating point-of-care assessments such as arterial blood gas analysis and osmolar gap evaluation in suspected cases are crucial, especially in resource-limited settings. Recognizing unexplained high anion gap metabolic acidosis with a high osmolar gap and characteristic MRI findings can aid in the early diagnosis and management of toxic alcohol poisoning

An Unusual Case of Alarming Lactic Acidosis: Brain Metabolic Cross-Talk

AbstractA 39-year-old male with a BMI of 30.8 kg/m2 and a normal medical history underwent excision of a left orbito-cavernal hemangioma (4 × 2 × 2 cm) under general anesthesia. Balanced anesthesia and fluid management guided by pulse pressure variation (kept below 12%) were employed. Despite stable hemodynamics and normal blood sugar levels, arterial blood gas (ABG) analysis revealed a progressive rise in lactate levels, reaching 10.6 mmol/L, accompanied by acidemia. Systemic hypoperfusion was ruled out by maintaining mean arterial pressure between 70-80 mm Hg, ensuring a capillary refill time of less than 3 seconds, and confirming a central venous oxygen saturation of 72%. With a total blood loss of 800 mL, one unit of packed red blood cells was transfused due to concerns about decreased microcirculation and tissue hypoxia. After 10 hours of surgery, sodium bicarbonate (NaHCO3) was administered to mitigate metabolic acidosis and its potential impact on intracranial pressure. Postoperatively, lactate levels remained elevated (8-9 mmol/L), but with continued NaHCO3 infusion, lactate reduced to 6.4 mmol/L, allowing extubation. The patient's lactate normalized by the evening, and recovery was uneventful. This case highlights the significant metabolic disturbances, particularly lactic acidosis, that can arise during brain tumor surgery due to prolonged operative times, large tumor size, higher BMI, and stress-induced metabolic derangements. Awareness and prompt management of these disturbances are crucial for successful patient outcomes.

Clinical evaluation of serum miR-513a-3p combined with arterial blood gas analysis parameters and lung ultrasound score in neonatal respiratory distress syndrome

BackgroundNeonatal respiratory distress syndrome (NRDS) is harmful to neonates and the prognosis is variable, ranging from mild to severe forms. This study aims to evaluate the clinical utility of miR-513a-3p in conjunction with arterial blood gas analysis parameters and lung ultrasound (LUS) score in the context of NRDS.MethodsThe study included 169 preterm infants, including 106 newborns with NRDS and 63 newborns without NRDS. The relative expression level of miR-513a-3p was detected by quantitative real time polymerase chain reaction (qRT-PCR). Umbilical artery blood gas parameter values and LUS score were recorded, and the clinical significance of miR-513a-3p, umbilical artery blood gas parameter and LUS score in NRDS were evaluated by Receiver Operating Characteristic (ROC) analysis.ResultsElevated levels of miR-513a-3p were detected in the serum of NRDS, and higher expression of miR-513a-3p was observed in individuals with poor prognosis. Notably, miR-513a-3p exhibited a significant correlation with the parameters of arterial blood gas analysis and LUS score in NRDS patients. Furthermore, miR-513a-3p was one of the risk factors for poor prognosis in NRDS patients. miR-513a-3p levels combined with umbilical artery blood gas parameters and LUS score has diagnostic value for NRDS and is reliable for its prognosis.ConclusionsElevated levels of miR-513a-3p in neonatal serum served as a useful tool in the combined assessment with umbilical artery blood gas analysis and LUS score to diagnosis and prognosis of NRDS. Consequently, miR-513a-3p may be served as a biomarker for diagnosis and prognosis of NRDS.

Evaluation of Dexmedetomidine with Tiletamine-Zolazepam for Snow Leopard (Panthera uncia) Immobilization.

This study describes two different doses of dexmedetomidine combined with tiletamine-zolazepam (TZ) for anesthesia in snow leopards (Panthera uncia). A total of 11 adult snow leopards were anesthetized in Xining City, Qinghai Province, China from November 2019 to June 2023. We recorded the onset time, anesthesia duration, head-up time, and walking time. Vital signs were recorded every 5 min during anesthesia. Arterial blood gas analysis was performed approximately 20 min after the onset of anesthesia by collecting blood from the femoral artery. All results were presented as mean±SD. There were no significant differences in onset time, anesthesia duration, head-up time, and walking time between the two anesthesia protocols. Heart rate, respiratory rate, body temperature, and blood pressure had a gradual decreasing trend, and blood oxygen saturation gradually increased. Our results suggest that using dexmedetomidine at doses of 21.25±1.38 μg/kg to 30.95±1.13 μg/kg combined with TZ at 2.07±0.08 mg/kg to 2.13±0.15 mg/kg can provide safe and effective anesthesia for snow leopards.

Phrenic Nerve Sonography Alterations in Patients with ALS: Insight with Clinical and Neurophysiological Findings.

Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder, and although the diagnosis is primarily based on clinical criteria, ENMG, as the "gold standard", does not always show detectable changes. Therefore, our study suggests that alterations in echogenicity and heterogeneity of the phrenic nerve (PN) may serve as potential additional diagnostic tools for ALS. Methods: Our study included 32 patients in the ALS group and 64 individuals in the control group. Each participant underwent an interview and completed questionnaires to collect clinical and demographic data, including age, gender, height, body mass index (BMI), hip and waist circumference, duration of illness, ALS-FRS-R score, comorbidities, and medication use. Ultrasound examinations of the PN were performed by two authors using a high-resolution "Philips EPIQ 7" ultrasound machine equipped with a linear 4-18 MHz transducer. The ALS group participants underwent PN sonography and conduction examinations, arterial blood gas (ABG) analysis, respiratory function tests (RFT), and electroneuromyography (ENMG). Results: The study demonstrated that the phrenic nerve is significantly smaller on both sides in patients with ALS compared to the control group (p < 0.01). Changes in the homogeneity and echogenicity of the PN were also observed on both sides. On the right side, 43.8% of the nerves showed heterogeneity, 40.6% were isoechoic, and 21.9% were hyperechoic. On the left side, 59.4% of the nerves exhibited heterogeneity, 34.4% were isoechoic, and 28.1% were hyperechoic. Moreover, sonography on both sides showed significant correlation with ALS-FRS-R, COMPASS-31, and ENMG results. Conclusions: Our study highlights the importance of phrenic nerve ultrasound as a promising supplementary diagnostic tool for ALS. The significant differences in phrenic nerve size, echogenicity, and homogeneity between patients with ALS and the control group demonstrate that ultrasound imaging can detect morphological changes in the phrenic nerve. Incorporating phrenic nerve ultrasound into routine diagnostic protocols could improve early detection, enhance disease monitoring, and offer a more comprehensive understanding of the neurodegenerative processes in ALS.

Temporal variations in and predictive values of ABG results prior to in-hospital cardiac arrest

In-hospital cardiac arrest (IHCA) has been understudied relative to out-of-hospital cardiac arrest. Further, studies of IHCA have mainly focused on a limited number of pre-arrest patient characteristics (e.g., demographics, number and types of comorbidities). Arterial blood gas (ABG) analysis, one of the most common diagnostic tests for assessing and managing critically or acutely ill hospitalized patients, reflects pathophysiological changes associated with adverse events or complications, including IHCA. Yet the predictive and prognostic values of patterns of pre-arrest ABG parameters for IHCA have not been fully studied. The purpose of this retrospective pilot cohort study was to investigate temporal variations in and predictive values of pre-IHCA ABG values among patients with a history of cardiopulmonary diseases. Eligible patients had a history of structural heart disease, heart failure, or pulmonary diseases. Patients were excluded if their IHCA was due to trauma, drug overdose, hypothermia, drowning, chronic terminal illness such as cancer or human immunodeficiency virus, or bleeding not caused by hemorrhage in the brain or heart. Also collected were dates, times, and causes of mechanical intubation prior to IHCA and causes of mortality. Co-primary outcomes were initial rhythms of IHCA and return of spontaneous circulation (ROSC). We conducted a pilot study and the ABG results (pH, partial pressure of carbon dioxide [PaCO2], partial pressure of oxygen [PaO2], bicarbonate [HCO3-] , and lactate) from each of the 3 days prior to IHCA were extracted from the electronic health records (EHRs) of patients (N = 44) who had experienced IHCA at a single medical center. To characterize differences in ABG parameters among study days, coefficients of variation (CVs) were compared using the modified likelihood ratio test (MLRT) using the worst ABG values. Linear regression models were run for the continuous ABG parameters and logistic regression models for the dichotomous ABG variables. Overall model effect and least squares means, SDs, mean differences within and between days (with 95 % confidence intervals), p-values and effect sizes were reported for continuous variables. For categorical variables, estimates and standard errors, 95 % confidence intervals, Wald X2 variables and p-values were presented. The CVs for pH, PaCO2, and HCO3- differed significant between study days (p <.05). The least squares means with 95 % confidence intervals for pH and lactate differed significantly in days (p <.01). Moderate to large effect sizes were obtained for all ABG parameters. Arterial lactate predicted initial rhythm (shockable versus non-shockable) and ROSC, while pH and HCO3- predicted ROSC. Results demonstrate, for the first time, the presence of significant variability in ABG parameters across 72 h prior to IHCA and the predictive potential of these parameters for initial rhythms of IHCA and ROSC. While validation in a larger sample is necessary, this study confirms the feasibility and potential value of exploring temporal patterns of pre-arrest ABG values from the EHRs. Findings of future larger studies on pre-arrest patterns of ABG parameters and other laboratory values may be used to design models that better predict risk for IHCA and guide patient care in the pre and intra-arrest periods.

Differentiation of Suspected Methanol Poisoning From Ethanol Poisoning: A Review Study and Consensus Statement

Background: Ethanol and methanol poisoning pose significant clinical challenges due to their overlapping clinical presentations. This literature review and consensus statement aim to provide evidence-based guidelines for differentiating these two poisonings.Methods: We conducted a comprehensive literature review of relevant literature, including individual patient data (IPD) meta-analysis, to assess clinical, laboratory, and diagnostic findings in cases with ethanol and methanol poisoning. A literature review was also performed to gather case series of electrocardiograms of ethanol and methanol poisoning. We synthesized the evidence and convened an expert panel to develop consensus-based recommendations.Results: Based on the literature review and IPD analysis, cases of methanol poisoning often present later than 24 hours after alcohol consumption, emphasizing the importance of assessing patients with delayed referrals. Methanol-poisoned patients are frequently awake and responsive after 12 hours of ingestion, but symptoms alone do not reliably differentiate between the two poisonings. Declines in visual acuity and symptoms are strongly associated with methanol poisoning and should prompt immediate hospitalization and ophthalmic examination. Oliguria and anuria are more common in cases of methanol poisoning, warranting detailed urinary symptom assessment and close monitoring of urinary output. Electrocardiograms are essential for all alcohol poisoning patients, with non-sinus rhythm suggesting methanol poisoning. Arterial blood gas analysis, with low pH values, favors methanol poisoning. However, blood sugar levels alone cannot definitively determine the type of poisoning. Laboratory point-of-care tests to diagnose methanol in serum are urgently needed.Conclusion: This literature review and consensus statement offer guidance for healthcare providers facing cases of alcohol poisoning where point-of-care testing methods of blood alcohol concentrations are unavailable. A comprehensive assessment, considering clinical history, physical examination, laboratory data, and specialized evaluations such as ophthalmic examination and electrocardiograms, is essential for accurately differentiating ethanol and methanol poisoning.

Acute Respiratory Failure in Children: A Clinical Update on Diagnosis.

Acute respiratory failure (ARF) is a sudden failure of the respiratory system to ensure adequate gas exchanges. Numerous clinical conditions may cause ARF, including pneumonia, obstructive lung diseases (e.g., asthma), restrictive diseases such as neuromuscular diseases (e.g., spinal muscular atrophy and muscular dystrophy), and albeit rarely, interstitial lung diseases. Children, especially infants, may be more vulnerable to ARF than adults due to anatomical and physiological features of the respiratory system. Assessing respiratory impairment in the pediatric population is particularly challenging as children frequently present difficulties in reporting symptoms and due to compliance and cooperation in diagnostic tests. The evaluation of clinical and anamnestic aspects represents the cornerstone of ARF diagnosis: first level exams (e.g., arterial blood gas analysis) confirm and evaluate the severity of the ARF and second level exams help to uncover the underlying cause. Prompt management is critical, with supplemental oxygen, mechanical ventilation, and the treatment of the underlying problem. The aim of this review is to provide a comprehensive summary of the current state of the art in diagnosing pediatric ARF, with a focus on pathophysiology, novel imaging applications, and new perspectives, such as biomarkers and artificial intelligence.

An algorithmic approach to arterial blood gas analysis for cardiologists

Abstract: An arterial blood gas (ABG) is a laboratory test to monitor the patient’s acid base balance. The body regulates pH closely to maintain homeostasis. This test is used to determine the magnitude of the compensation by the buffer system and includes the measurements of the acidity (pH), levels of oxygen, and carbon dioxide in arterial blood. Acid base disorders can lead to severe complications in many disease states. ABG interpretation is paramount in critically ill patients. Many methods already exist to guide the interpretation of the ABG. This article does not include methods such as analysis of base excess or Stewart’s strong ion difference. It is paramount for cardiologists to understand ABG interpretation to manage their patients effectively. Interpreting ABGs may seem complex, but a systematic approach is required to diagnose and treat disorders by quick and easy ABG interpretation.

Assessment of IV albumin and ringer lactate on the acute oral toxicity of acetylsalicylic acid in albino rats

BackgroundDespite the frequent inclusion of fluid therapy in the treatment of many conditions, there are limited studies available to provide an evidence-based specific recommendation for fluid therapy in acute drug toxicity. Salicylate toxicity is considered one of the common clinical problems. It is commonly associated with fatal complications and even can lead to death. The study was designed to investigate the effects of various IV fluid types as isotonic saline (NaCl 0.9%), Ringer lactate (RL), and albumin and their impact on acetyl salicylic acid (ASA) toxicity outcome in a rat model of acute salicylate toxicity.Sixty male Albino rats were divided into 10 groups of 6 rats each. The first four groups were the control, saline, RL, and albumin groups. The fifth group received two doses of ASA solution orally, and the next five groups were treated with IV fluids as follows: saline-ASA, RL-ASA, albumin-ASA, RL + albumin-ASA, and saline + albumin-ASA. Upon completion of the study, spirometry, arterial blood gas analysis (ABG), and serum liver and kidney function tests were done on all groups. Furthermore, quantitative real-time polymerase chain reaction (PCR) was used to assess interleukin-6 (IL6), nuclear factor kappa beta (NF-kβ), and beta-actin mRNA gene expression of histopathology and immunohistochemistry assessments were also performed on liver and kidney tissues.ResultsThe results revealed the ASA group showed marked deterioration across all the investigated parameters. The groups that received saline and RL showed improvements in the following: respiratory rates, ABG, liver and kidney function, and histopathological findings.The RL + albumin group did not show any improvements. The albumin group and the saline + albumin group showed variable responses, ranging from mild improvement to no improvement.ConclusionsThe saline and RL groups showed positive results; however, the RL + albumin group showed the worst outcomes. The inclusion of albumin did not appear to provide any extra benefits and produced varying results.

Arterial blood gas analysis in cardiac emergencies of dogs

Arterial blood gas analysis in cardiac emergencies of dogs

8243 Euglycemic Diabetic Ketoacidosis Unveiled: Delayed Presentation and Complications of SGLT-2 Inhibitor Therapy in a Multimorbid Patient - A Case Report

Abstract Disclosure: T. Amin: None. A.K. Bala: None. M.A. Jones: None. M.S. Akula: None. K. Chalasani: None. M. Patel: None. J. Cheng: None. Introduction: Normal serum glucose levels (&amp;lt;200 mg/dL) in euglycemic diabetic ketoacidosis (EDKA) can complicate the typical clinical presentation of diabetic ketoacidosis (DKA), posing a diagnostic challenge. SGLT-2 inhibitors, a class of antihyperglycemic drugs, have been rarely but significantly associated with EDKA. These inhibitors enhance renal glucose clearance by preventing glucose reabsorption via sodium-glucose cotransport. The increased renal clearance may contribute to the euglycemic picture, potentially leading to an underestimation of required insulin dosage, thereby precipitating ketoacidosis in EDKA. Although the mechanisms of EDKA are not fully understood, the association with SGLT-2 inhibitors is becoming increasingly evident. Case A 53-year-old male with a medical history of type 2 Diabetes Mellitus, coronary artery disease, chronic kidney disease, hyperlipidemia, was admitted to the trauma bay after a fall. Medications included empagliflozin, metformin, aspirin, amlodipine, spironolactone, and carvedilol. Upon presentation, he had a brief loss of consciousness, complained of headache and chest pain, and was found to have an epidural hematoma with regional brain compression on the CT head. Admission labs showed a blood glucose level of 172, an unremarkable anion gap, and normal renal and liver function tests. Due to traumatic brain injury, he was admitted to the ICU for neurological monitoring. Despite remaining neurologically stable, he developed hypoxia, necessitating intubation. After successful extubation, he exhibited worsening metabolic acidosis on the fourth day, with an elevated anion gap of 22 and a blood glucose level of 174. Arterial blood gas analysis revealed a pH of 7.3 (and elevated beta-hydroxybutyrate (&amp;gt;4), while lactic acid levels remained normal. Urine analysis showed elevated blood glucose (&amp;gt;1000) and ketones (&amp;gt;40). Home medications, metformin, and empagliflozin were appropriately withheld, but euglycemic DKA attributed to empagliflozin was diagnosed. Treatment included intravenous fluid resuscitation and insulin infusion, leading to resolution of acidosis and improved mentation within 24 hours. Conclusion: EDKA is a diagnosis of exclusion often overlooked in ICU patients due to diverse causes of high-anion gap metabolic acidosis. Typical cases occur while the patient is using the drug, often associated with triggers like illness, alcohol use, surgery, or starvation. SGLT2 inhibitors, such as empagliflozin, with a half-life of 12.4 hours, are expected to clear the bloodstream in about 48 hours, yet this case suggests an association with EDKA both during use and after drug cessation. This delayed presentation highlights additional risk considerations associated with SGLT2 inhibitors, guiding future clinical diagnoses of EDKA even several days post discontinuation. Presentation: 6/3/2024

Assessment of accuracy of two pulse oximeters in infants with cyanotic and acyanotic congenital heart diseases.

Peripherally measured oxygen saturation (SpO2) may often differ from arterial oxygen saturation (SaO2), measured by co-oximetry, especially within the lower range of oxygen saturations. This can potentially impact clinical decisions and therapy in children with congenital heart disease, as critical hypoxemia might remain unnoticed. Our aim was to investigate the accuracy of two different pulse oximeters compared to SaO2 in infants with congenital heart diseases. Simultaneous recordings of SpO2, measured by two different pulse oximeters (Philips IntelliVue X3 Monitor and Nellcor™ OxiMax™), were compared to SaO2 obtained by arterial blood gas analysis. A total of 153 measurements were performed in 44 infants with arterial oxygen saturation between 70 and 100%. We divided the measurements into 3 subgroups: group 1-SaO2 70.0%-85.0%, group 2-SaO2 85.1%-94.0%, group 3-SaO2 >94.1%. For Philipps, the median bias was 5.3 (IQR: 2.6-8.7) %, 2.3 (IQR: 0.9-6.0) % and 1.1 (IQR: -0.8-2.4) % in group 1, 2 and 3, respectively. For OxiMax™, the median bias was 2.7 (IQR: 0.5-5.1) %, 0.2 (IQR: -0.9-2.6) % and -0.5 (IQR: -1.3-0.6) % in group 1, 2 and 3, respectively. Regarding the accuracy of these oximeters, as evaluated with the Accuracy root mean squared index (Arms), it was 9.8 versus 4.5% in group 1, 4.5 versus 2.9% in group 2 and 2.4 versus 1.9% in group 3 for Philipps and OxiMax™, respectively. In lower range saturations between 70% and 85% the accuracy of both pulse oximeters exceeded the threshold of ≤3% recommended by the Food and Drug Administration (FDA). Therefore, peripheral pulse oximetry within the lower range of oxygen saturations should be interpreted with caution in infants with congenital heart diseases, taking into consideration its limitations. Direct co-oximetry should be the preferred method to support clinical decisions in children with cyanotic congenital heart diseases.

Comparison of the Volumetric Parameters of Platelets in Diabetic Children with and without Diabetic Ketoacidosis: A Case-Control Study in the North of Iran

Background: This study aimed to determine the volumetric parameters of platelets including MPV (Mean Platelet Volume) and PDW (Platelet Distribution Width) in diabetic children with and without diabetic ketoacidosis (DKA) and to evaluate their relationship with the severity of DKA. Materials and Methods: A case-control study was conducted on 112 children with type 1 diabetes mellitus (T1DM), with and without DKA, who referred to Amirkola Children's Hospital, Iran, in 2016-2021. Of them, 43 were boys, and 69 were girls. The diagnosis of diabetes was based on clinical symptoms and diagnostic criteria, and DKA was diagnosed through the analysis of arterial blood gas. The patients’ MPV and PDW were also evaluated, and the P values less than 0.05 were considered significant. Results: Out of 112 children with diabetes (with the mean age of 8.71 ± 3.22 years), 56 persons had DKA. In terms of DKA severity, 17 patients (30.4%) had mild, 29 (51.8%) had moderate, and 10 (17.8%) had severe DKA. The children with DKA had the mean blood glucose of 490.98±46.11mg/dL, MPV of 10.02± 1.19fl), and PDW of 13.07± 1.18flwere significantly higher (P&lt;0.001). It was found that, an increase in the severity of DKA would raise the mean MPV (P = 0.006) and PDW(P&lt;0.001) significantly. Conclusion: Based on the results of this study, as the severity of DKA increases in diabetic children, the mean levels of MPV and PDW increase significantly. Therefore, it is suggested that MPV and PDW be used to predict the severity of DKA in diabetic children.

Cardiopulmonary exercise testing in patients with obstructive sleep apnea

Background The cardiopulmonary exercise testing (CPET) is a noninvasive process aiming to evaluate the respiratory and cardiovascular system during exercise. Aim To study the effect of obstructive sleep apnea (OSA) on cardiovascular system and exercise capacity and to correlate the severity of OSA with CPET parameters. Patients and methods Fifty patients (30 males and 20 females) were enrolled in this study, diagnosed as OSA based on polysomnography (apnea–hypopnea index ≥5). All patients were given a thorough medical history, a thorough physical examination, an arterial blood gas analysis before and after exercise, a pulmonary-function test, polysomnography, and a CPET. Results Patients with mild/moderate OSA had significantly higher oxygen consumption (VO2) at peak (ml/min) and predicted value. Predicted VO2/kg was significantly higher among patients with mild/moderate OSA. Also, patients with mild/moderate OSA had significantly higher LT. Out of enrolled patients, three (6%), 15 (30%), and 32 (64%) patients had mild, moderate, and severe exercise impairment, respectively. Majority (90%) of the patients with severe OSA had severe exercise impairment, while majority (70%) of those with mild/moderate OSA had moderate exercise impairment. Conclusions OSA causes exercise impairment, which has a positive correlation with the severity of the disease.

Shock wave damage from the ventral side in primary blast injury: An experimental study in pigs

Aim/PurposeThis study aimed to apply a shock wave from the ventral side of a pig and examine its effect to use the results for new body armor production for humans. MethodsSeven male hybrid pigs were used. Each pig was placed under general anesthesia on the experimental table in a blast tube to expose the left lateral position from the front chest area, and shock waves generated by compressed air at 3.0 MPa were applied. We examined changes in vital signs and arterial blood gas in the hyper-acute phase and computed tomography (CT) images, and autopsies were performed for organ damage after 3 h of observation. Pathological examination was performed for lung damage, which is considered a characteristic of shock wave injury. ResultsAll seven pigs survived. Respiratory arrest occurred in two pigs; however, spontaneous breathing resumed promptly afterward. Hypotension occurred at a frequency of 4. No bradycardia or cardiac arrest was observed in any pig. In the arterial blood gas analysis before and immediately after shock wave exposure and 1 hour later, PaO2 decreased immediately but tended to improve thereafter. CT revealed pulmonary contusions and multiple bulla-like lesions on the surface of the lungs. An autopsy showed lung injury in all pigs, particularly in five cases with bulla-like lesions of various sizes on the lung surface across all lobes. Pathological findings showed visceral pleural detachment with elastic fibers from the lung parenchyma, and the cavity lesion on the lung surface comprised bullae. The degree of intra-abdominal hemorrhage varied; however, all but one case showed splenic injury. ConclusionNone of the pigs exposed to shock waves from the ventral side died; however, most showed multiple bullae on the lung surface with lung contusion and splenic injury, which may have been greater than those exposed from the dorsal side. This may be due to the direct impact of the shock wave proceeding from the epigastrium and subcostal region, which are not protected by the skeletal structure of the thorax. These characteristics should be considered when producing new body armor for humans to protect the body from shock waves.

Fetal haemoglobin and oxygen requirement in preterm infants: an observational study

ObjectiveTo investigate the relationship between the fraction of fetal haemoglobin (HbF(%)) and oxygen requirement as determined by the fraction of inspired oxygen (FiO2) and alveolar–arterial gradient (A–a gradient). Increased alveolar...

Association of Prenatal Maternal Fever and Neonatal Umbilical Artery Blood-Gas Analysis: Evidence from a Tertiary Center at China

Background: Neonatal umbilical artery blood-gas analysis is a diagnostic procedure performed shortly after birth to assess the acid-base balance, oxygenation, and metabolic status of a newborn infant. This retrospective study aimed to investigate the association of prenatal maternal fever with neonatal umbilical artery blood-gas analysis. Methods: A retrospective analysis was conducted on data from 333 parturients and their newborns. Demographic characteristics, clinical information, and neonatal umbilical artery blood gas analysis data were analyzed to evaluate the association between prenatal maternal fever and neonatal blood-gas analysis. Pregnant women with fever (≥38.0 °C) during labor were compared with those without fever. Neonatal umbilical artery blood gas parameters were assessed in relation to the degree and duration of maternal fever. Results: The incidence of the adverse delivery outcome of parturients with high prenatal fever and long duration of fever was significantly higher than that of the low fever, short-term fever, and normal parturients (p &lt; 0.05). The pH of neonatal umbilical veins in the high fever groups was reduced compared with the control group (p &lt; 0.05). Lactic acid (Lac) of neonatal umbilical vein in the low fever and high fever groups was enhanced compared with the control group (p &lt; 0.05). The pH of neonatal umbilical veins in the short-term fever and long-term fever groups was elevated compared with the control group (p &lt; 0.05). The umbilical artery pH and base excess (BE) were positively correlated with maternal peak fever temperature (r = 0.20, r = 0.22, p &lt; 0.05). The umbilical Lac was negatively correlated with maternal peak fever temperature (r = –0.22, p &lt; 0.05). Moreover, the umbilical artery pH and BE were positively correlated with maternal duration of fever (r = 0.29, r = 0.21, p &lt; 0.05). The umbilical artery Lac was negatively correlated with maternal duration of fever (r = –0.25, p &lt; 0.05). Conclusions: The findings suggested that maternal fever during labor was associated with alterations in neonatal umbilical artery blood gas analysis. Understanding the influence of prenatal fever on delivery outcomes is crucial for optimizing maternal and neonatal health.

Clinical variability of equine asthma phenotypes and analysis of diagnostic steps in phenotype differentiation

BackgroundEquine asthma is a common, non-infectious, chronic lung disease that affects up to 80% of the horse population. Strict phenotyping and identification of subclinically asthmatic horses can be challenging. The aim of this study was to describe equine asthma phenotypes (mild, moderate, and severe asthma) defined by BALF cytology and occurrence of clinical signs in a population of privately owned horses and to identify the variables and examination steps with best discriminative potential. The standardised examination protocol included clinical examinations, blood work, airway endoscopy with bronchoalveolar lavage fluid analysis, arterial blood gas analysis and radiography under clinical conditions performed by one veterinarian.ResultsOut of 26 horses, four were diagnosed with mild (subclinical), seven with moderate, and seven with severe asthma based on clinical examination and BALF cytology. Eight horses served as controls. Cough with history of coughing was the strongest variable in phenotype differentiation. Factor analysis revealed an increasing clinical variability with disease severity and an overlapping of clinical presentations between phenotypes. Elevated mast cell (4/4 horses) and neutrophil counts (3/4 horses) in bronchoalveolar lavage cytology differentiated mild asthmatic horses from healthy horses. Moderate and severe asthmatic horses were characterised by clinical signs and neutrophil counts.ConclusionsThe results indicate that medical history, clinical examination and bronchoalveolar lavage cytology are minimum indispensable steps to diagnose equine asthma and that phenotypes are clinically overlapping. A differentiation of three phenotypes without neutrophil and mast cell counts in bronchoalveolar lavage cytology is not sufficient for clinical diagnostics. A comparably exact diagnosis cannot be achieved by relying on alternative examinations used in this study. Screenings of inconspicuous horses with bronchoalveolar lavage can aid in diagnosing subclinically affected animals, however, group size was small, the procedure is invasive and clinical relevance of slightly elevated cells in bronchoalveolar lavage remains unclear. Clinical relevance could not be clarified in this study, since follow-up examinations or lung function testing were not performed.

Effects of Dexmedetomidine in Improving Oxygenation and Reducing Pulmonary Shunt in High-Risk Pediatric Patients Undergoing One-Lung Ventilation for Thoracic Surgery: A Double-Blind Randomized Controlled Trial.

Background and objectives Pediatric thoracic surgery has unique considerations due to the immaturity of the respiratory system anatomically and physiologically, which presents technical and pharmacological considerations, including the very common technique of one-lung ventilation (OLV), which causes serious complications in children. Therefore, we investigated the effects of dexmedetomidine on oxygenation and pulmonary shunt fraction (Qs/Qt) in high-risk pediatric patients undergoing OLV for thoracic surgery. This randomized controlled trial aimed to investigate dexmedetomidine's effect on the partial pressure of arterial oxygen (PaO2) and pulmonary shunt fraction (Qs/Qt). Methods A total of 63 children underwent thoracic surgery with OLV and were divided into two groups. The dexmedetomidine group (group Dex, n = 32) received dexmedetomidine (0.4 μg/kg/hour), and the placebo group (group placebo, n = 31) received normal saline. Two arterial and central venous blood samples were taken for arterial and venous blood gas analysis at four time points: T1 (10 minutes after mechanical ventilation of total lung ventilation), T2 (10 minutes after OLV), T3 (60 minutes after OLV), and T4 (20 minutes after the end of OLV). At these intervals, the following parameters were measured: PaO2, Qs/Qt, mean arterial pressure (MAP), heart rate (HR), and peak inspiratory pressure (PIP). Results The two groups had no significant differences in FEV1/FVC and baseline pulmonary shunt fraction (Qs/Qt). Dexmedetomidine significantly improved PaO2 compared with placebo during OLV (T2 and T3). There was a significant decrease in Qs/Qt compared with placebo during OLV (T2, T3, and T4). There was a decrease in PIP compared with placebo during OLV (T2 and T3). No statistically significant differences in MAP or HR were observed between the groups. Conclusion Infusion of dexmedetomidine during OLV in high-risk pediatric thoracic surgery reduces shunt and pulmonary shunt fraction Qs/Qt, improves PaO2 and body oxygenation, reduces PIP and pressure load, and maintains hemodynamic stability (MAP, HR).