Carbon Dioxide In Arterial Blood Research Articles

A case of high cervical cord infarction presenting with cardiopulmonary arrest due to respiratory dysfunction

A 46-year-old man with neck pain and impaired physical mobility called for emergency medical services. The patient was able to communicate with the emergency medical team upon their arrival. However, he went into cardiopulmonary arrest 5 minutes later. Cardiopulmonary resuscitation was immediately performed, and the patient was admitted to our hospital with a Glasgow Coma Scale score of E1V1M1. His respiratory rate was 5 breaths/minute and his partial pressure of carbon dioxide in arterial blood (PaCO2) was 127 ‍mmHg, necessitating intubation and ventilation. His consciousness improved as the PaCO2 level decreased. However, he was unable to be weaned off the ventilator and breathe independently. Neurological examination revealed flaccid quadriplegia, pain sensation up to the C5 level, absence of deep tendon reflexes, indifferent plantar responses, and absence of the rectoanal inhibitory reflex. Magnetic resonance imaging showed a hyperintense lesion with slight enlargement of the anterior two-thirds of the spinal cord at the C2-C4 level on both T2-weighted and diffusion-weighted images, consistent with a diagnosis of spinal cord infarction. Although the quadriplegia and sensory loss partially improved, the patient was unable to be weaned from the ventilator. Cervical cord infarction of the anterior spinal artery can cause rapid respiratory failure leading to cardiopulmonary arrest. Therefore, cervical cord infarction should be included as a differential diagnosis when examining patients after cardiopulmonary resuscitation.

Effects of Butorphanol on Respiration in White Rhinoceros (Ceratotherium simum) Immobilized with Etorphine-Azaperone.

This article reports on respiratory function in white rhinoceros (Ceratotherium simum) immobilized with etorphine-azaperone and the changes induced by butorphanol administration as part of a multifaceted crossover study that also investigated the effects of etorphine or etorphine-butorphanol treatments. Six male white rhinoceros underwent two immobilizations by using 1) etorphine-azaperone and 2) etorphine-azaperone-butorphanol. Starting 10 min after recumbency, arterial blood gases, limb muscle tremors, expired minute ventilation, and respiratory rate were evaluated at 5-min intervals for 25 min. Alveolar to arterial oxygen gradient, expected respiratory minute volume, oxygen consumption, and carbon dioxide production were calculated. Etorphine-azaperone administration resulted in hypoxemia and hypercapnia, with increases in alveolar to arterial oxygen gradient, oxygen consumption, and carbon dioxide production, and a decrease in expired minute ventilation. Muscle tremors were also observed. Intravenous butorphanol administration in etorphine-azaperone-immobilized white rhinoceros resulted in less hypoxemia and hypercapnia; a decrease in oxygen consumption, carbon dioxide production, and expired minute ventilation; and no change in the alveolar to arterial oxygen gradient and rate of breathing. We show that the immobilization of white rhinoceros with etorphine-azaperone results in hypoxemia and hypercapnia and that the subsequent intravenous administration of butorphanol improves both arterial blood oxygen and carbon dioxide partial pressures.

Arterial blood gas measurements are different for brachycephalic and nonbrachycephalic dogs acclimatized to an altitude of 1,535 meters.

To define reference intervals (RIs) for arterial blood gas (aBG) measurements in healthy, nonsedated, dolichocephalic, and mesocephalic (nonbrachycephalic) dogs at approximately 1,535 m above sea level and compare these findings with healthy, nonsedated, brachycephalic dogs living at the same altitude. 120 adult nonbrachycephalic dogs and 20 adult brachycephalic dogs. Cases were prospectively enrolled from October 2021 to June 2022. Dogs were enrolled from the community or after presentation for wellness examinations or minor injuries including lacerations, nail injuries, and lameness. Physical examinations and systolic blood pressure (sBP) measurements were obtained before blood sample collection. Arterial blood was collected from the dorsal pedal artery or femoral artery. After data collection, brachycephalic dogs underwent pre- and postexercise tolerance assessments. The mean and RI values for arterial pH (7.442; 7.375 to 7.515), partial pressure of oxygen in arterial blood (Pao2; 78.3; 59.2 to 92.7 mm Hg), partial pressure of carbon dioxide in arterial blood (Paco2; 28.0; 21.5 to 34.4 mm Hg), saturation of arterial oxygen (Sao2; 98.4; 84.3% to 101.4%), HCO3 (18.9; 14.9 to 22.4 mmol/L), concentration of total hemoglobin (ctHb; 17.5; 13.4 to 21.1 g/dL), and sBP (133; 94 to 180 mm Hg) were established for healthy nonbrachycephalic dogs at 1,535-m altitude. All aBG measurements were statistically and clinically different from those previously reported for dogs at sea level. Brachycephalic dogs had significantly lower Pao2 and Sao2 (P = .0150 and P = .0237, respectively) and significantly higher ctHb (P = .0396) compared to nonbrachycephalic dogs acclimatized to the same altitude; the nonbrachycephalic RIs were not transferable to the brachycephalic dogs for Pao2. This study represents the first collation of aBG measurements for healthy nonbrachycephalic dogs acclimatized to an altitude of 1,535 m. Additionally, this study identified differences in arterial oxygenation measurements between brachycephalic and nonbrachycephalic dogs. RIs in brachycephalic dogs need to be established.

Impact of COVID-19-associated Dysautonomia Phenotypes on the Effectiveness of Venovenous Extracorporeal Membrane Oxygenation

RELEVANCE. It is known that patients with severe cases of the novel coronavirus infection (COVID-19) are characterized by the development of COVID-19-associated dysautonomia (COVID-19-DA). At the moment, there are no studies examining the impact of this phenomenon on the course and outcomes of the disease in the most severe cohort of patients with COVID-19, namely those requiring venovenous extracorporeal membrane oxygenation (VV ECMO). AIM OF STUDY. The purpose of the presented work is to study the effect of different COVID-19-DA phenotypes on the performance parameters and effectiveness of VV ECMO, gas exchange and hemodynamics in patients with COVID-19. MATERIAL AND METHODS. The study included 20 patients, 12 (60%) women, 8 (40%) men, with COVID-19 who underwent VV ECMO. Patients underwent 24-hour Holter monitoring with assessment of the spectral parameters of heart rate variability (HRV): the low-frequency component (LF), the high-frequency component (HF), the ratio of the low-frequency component to the high frequency component (LF / HF) on days 1, 3, 5 of the VV ECMO. Patients were divided into three groups based on the identified COVID-19-DA phenotypes. The groups were compared in terms of gas exchange, hemodynamics, and VV ECMO performance parameters. RESULTS. The level of partial pressure of carbon dioxide in arterial blood (paCO2) in the phenotype with low sympathetic tone and high tone of the parasympathetic division of the autonomic nervous system (ANS) (lShP) was significantly higher than in the phenotype with normal sympathetic tone and high tone of the parasympathetic division of the ANS (nShP) with equal VV ECMO performance parameters. The heart rate (HR) in the nShP phenotype was significantly lower than in the lShP phenotype. A significant increase in respiratory dysfunction was revealed over time in the lShP phenotype. Weaning from VV ECMO in the nShP phenotype was successful in 50 %, whereas in the lShP phenotype, weaning from VV ECMO was observed in 7,2 % of patients. No significant differences in the mortality rate were obtained. The most common cause of death in both groups was septic shock. CONCLUSIONS. The COVID-19-DA phenotype, manifested by decreased tone of the sympathetic division and increased tone of the parasympathetic division of the ANS, leads to low efficiency of VV ECMO, resulting in a statistically significantly less frequent ECMO discontinuation in those patients.

Effects of restrictive fluid resuscitation on the clinical efficacy of treating traumatic hemorrhagic shock combined with traumatic coagulopathy

This study aims to assess the clinical efficacy of limited fluid resuscitation on traumatic hemorrhagic shock combined with traumatic coagulopathy. A cohort of 120 patients with traumatic hemorrhagic shock complicated with traumatic coagulopathy at admission were divided into two groups based on their emergency fluid resuscitation: the study group (received restrictive fluid resuscitation) and the control group (received conventional fluid resuscitation). Then, the incidence of complications, coagulation parameters, blood gas parameters and electrolyte parameters between the two groups were compared. The incidence of complications in the study group was 6.67%, which was significantly lower than the 20.00% observed in the control group (p < 0.05). Before resuscitation, there was no significant difference in coagulation parameters, blood gas parameters and electrolyte parameters between the two groups (p > 0.05), and in both groups, before and after resuscitation, the coagulation parameters after resuscitation were higher than those before resuscitation, blood gas parameters were lower than those before resuscitation, Mg2+, Cl− and Na+ levels were higher than those before resuscitation, K+ was lower than that before resuscitation, and the difference had statistical significance (p < 0.05). After resuscitation, the coagulation parameters in the study group were significantly lower than those in the control group, the BL (Blood Lactic Acid) and PaCO2 (partial pressure of carbon dioxide in arterial blood) levels in the study group were lower than those in the control group, the BE (base excess) and PaO2 levels were higher than those in the control group, and the differences were statistically significant (p < 0.05). However, after resuscitation, we found no significant difference in electrolyte parameters between both groups (p > 0.05). Restrictive fluid resuscitation was found to significantly enhance coagulation and blood gas function, stabilize water and electrolyte balance and reduce complications in traumatic hemorrhagic shock patients complicated with traumatic coagulopathy. These findings hold substantial clinical significance and merit further exploration.

Effectiveness of Structured Teaching Programme on Knowledge Regarding Arterial Blood Gas Analysis among Nursing Students in Chitwan, Nepal A Pre-experimental One Group Pretest Post-test Design

Background: Arterial blood gas (ABG) analysis measures blood pH, oxygen (O2), and carbon dioxide (CO2) levels. Normal pH is 7.35-7.45, PaO2 ranges from 70-100 mm Hg, PaCO2 is 35-45 mm Hg, and SaO2 is 93-98%. HCO3 normal value is 22-26 meq/l. This study assesses the effectiveness of a structured teaching program on arterial blood gas analysis knowledge among nursing students. Methods: A pre-experimental study with a one-group pretest-posttest design evaluated the effectiveness of a structured teaching program on Arterial Blood Gas analysis knowledge among nursing students from two Purbanchal University-affiliated colleges. Narayani Samudayik Nursing College was chosen using a probability-based simple random sampling lottery method. Enumerative sampling was employed to select respondents for the study. Results: The study found that 87% of respondents initially had an average knowledge level of arterial blood gas analysis, with 13% having adequate knowledge. After intervention, 82.6% demonstrated adequate knowledge, and 17.4% maintained an average level. Mean knowledge scores significantly increased from 67.15 to 87.7 in pretest and posttest, respectively (p<0.001). The results affirm the intervention's effectiveness in improving participants' understanding of arterial blood gas analysis..Conclusion: Most respondents had average knowledge of ABG analysis. Following the structured teaching program, the majority achieved adequate knowledge, demonstrating its significant positive impact in enhancing nursing students' unde standing of ABG analysis.

Characterization of a Waveguide with 45 Degrees Reflectors for the Detection of Carbon Dioxide

This paper investigates the characteristics of the angle of incidence of a waveguide with 45 degrees reflectors. Non-dispersive infrared (NDIR) gas sensors consist of an infrared source, a waveguide, and an infrared detector. The waveguide especially plays a part in an infrared path and gas cell. According to the Beer-Lambert law, the NDIR sensor with longer ray traveling path shows a higher response to the target gas. Also of particular interest is that the normal incidence ratio toward an infrared detector enhances the NDIR sensor selectivity for the target gases as well as the sensitivity. While there has been significant research on the effect on sensitivity by designing waveguide structures or ray traveling distance, this paper focuses on understanding the incidence of light toward the infrared detector by the waveguide with 45 degrees reflector and how this affects the selectivity of the sensor. A Ray tracing simulation is adopted to analyze the effect of the number of 45 degrees reflectors on the distribution of the incidence. Furthermore, a non-dispersive infrared gas sensor is applied to measure how the number of the reflectors affect to the selectivity for the target gas. The results reveal the enhancement of the selectivity by the reflectors.AcknowledgementsThis work was supported by the Korea Innovation Foundation(INNOPOLIS) grant funded by the Korea government(MSIT) (2020-DD-UP-0348). This study has been conducted with the support of the Korea Institute of Industrial Technology as "Development and commercialization for clean hydrogen production/storage and CO2 monitoring system in the field of industrial complex" (Kitech EH-23-0012) This work was supported by the Technology Innovation Program (155736, Development of Miniaturized Sensor Module Technology for Non-invasive Arterial Blood Carbon Dioxide Real-time Monitoring) funded By the Ministry of Trade, Industry & Energy(MOTIE, Korea). Figure 1

Acid-Sensing Ion Channels' Immunoreactivity in Nerve Profiles and Glomus Cells of the Human Carotid Body.

The carotid body is a major peripheral chemoreceptor that senses changes in arterial blood oxygen, carbon dioxide, and pH, which is important for the regulation of breathing and cardiovascular function. The mechanisms by which the carotid body senses O2 and CO2 are well known; conversely, the mechanisms by which it senses pH variations are almost unknown. Here, we used immunohistochemistry to investigate how the human carotid body contributes to the detection of acidosis, analyzing whether it expresses acid-sensing ion channels (ASICs) and determining whether these channels are in the chemosensory glomic cells or in the afferent nerves. In ASIC1, ASIC2, and ASIC3, and to a much lesser extent ASIC4, immunoreactivity was detected in subpopulations of type I glomus cells, as well as in the nerves of the carotid body. In addition, immunoreactivity was found for all ASIC subunits in the neurons of the petrosal and superior cervical sympathetic ganglia, where afferent and efferent neurons are located, respectively, innervating the carotid body. This study reports for the first time the occurrence of ASIC proteins in the human carotid body, demonstrating that they are present in glomus chemosensory cells (ASIC1 < ASIC2 > ASIC3 > ASIC4) and nerves, presumably in both the afferent and efferent neurons supplying the organ. These results suggest that the detection of acidosis by the carotid body can be mediated via the ASIC ion channels present in the type I glomus cells or directly via sensory nerve fibers.

Death by Neurologic Criteria in Children Undergoing Extracorporeal Cardiopulmonary Resuscitation: Retrospective Extracorporeal Life Support Organization Registry Study, 2017-2021.

To determine factors associated with brain death in children treated with extracorporeal cardiopulmonary resuscitation (E-cardiopulmonary resuscitation). Retrospective database study. Data reported to the Extracorporeal Life Support Organization (ELSO), 2017-2021. Children supported with venoarterial extracorporeal membrane oxygenation (ECMO) for E-cardiopulmonary resuscitation. None. Data from the ELSO Registry included patient characteristics, blood gas values, support therapies, and complications. The primary outcome was brain death (i.e., death by neurologic criteria [DNC]). There were 2,209 children (≥ 29 d to < 18 yr of age) included. The reason for ECMO discontinuation was DNC in 138 patients (6%), and other criteria for death occurred in 886 patients (40%). Recovery occurred in 1,109 patients (50%), and the remaining 76 patients (4%) underwent transplantation. Fine and Gray proportional subdistribution hazards' regression analyses were used to examine the association between variables of interest and DNC. Age greater than 1 year ( p < 0.001), arterial blood carbon dioxide tension (Pa co2 ) greater than 82 mm Hg ( p = 0.022), baseline lactate greater than 15 mmol/L ( p = 0.034), and lactate 24 hours after cannulation greater than 3.8 mmol/L ( p < 0.001) were independently associated with greater hazard of subsequent DNC. In contrast, the presence of cardiac disease was associated with a lower hazard of subsequent DNC (subdistribution hazard ratio 0.57 [95% CI, 0.39-0.83] p = 0.004). In children undergoing E-cardiopulmonary resuscitation, older age, pre-event hypercarbia, higher before and during ECMO lactate levels are associated with DNC. Given the association of DNC with hypercarbia following cardiac arrest, the role of Pa co2 management in E-cardiopulmonary resuscitation warrants further studies.

Efficacy of different respiratory supports to prevent hypoxia during flexible bronchoscopy in patients of COPD: a triple-arm, randomised controlled trial

BackgroundPatients with chronic-obstructive-pulmonary-disease (COPD) undergo bronchoscopy for various reasons, and are at relatively higher risk of complications. This study evaluated the efficacy of non-invasive ventilation (NIV) and high-flow-oxygen-therapy (HFOT) compared...

Arterial blood analysis of healthy residents in Huamachuco, Peru (3,164 m): a cross-sectional study.

Background: Given that arterial blood gas is affected by altitude and ethnicity, establishing reliable reference standards for these values requires analysis of arterial blood at different elevations and locations. Our objective was to measure the arterial blood gases of healthy young volunteers in Huamachuco, Peru, at 3,164 m above sea level. This is likely the first study of arterial blood gas analysis of healthy Northern Peruvians living at high altitude. Methods: Healthy residents of Huamachuco were recruited for this cross-sectional convenience sample study and arterial blood was drawn by standard procedures. People with obesity, diabetes, high levels of physical activity and a history of using selected substances were excluded. The samples were analyzed on-site in less than 15 minutes using a Stat Profile Prime CCS analyzer (Nova Biomedical). Results: Data from 46 participants (17 male, 29 female) were included in the study. The median values for arterial blood pH, oxygen, carbon dioxide, ionized calcium, glucose, lactate, hematocrit, oxygen saturation, and bicarbonate were 7.42, 9.3 kPa (70 mmHg), 4.5 kPa (33.5 mmHg), 1.04 mM, 5.19 mM, 1.8 mM, 50 %, 94 %, and 21.6 mM, respectively. We also found a lower prevalence of diabetes among highlanders compared to the Peruvian population. Conclusions: The results determined here were comparable to other results determined at different altitudes in the Americas, although arterial blood oxygen was slightly higher than predicted. These results indicate that Northern Peruvians have an Andean-style adaptation to high altitude.

Effect of cerebral oxygen saturation monitoring in patients undergoing superficial temporal anterior-middle cerebral artery anastomosis for ischemic Moyamoya disease: a prospective cohort study.

Regional cerebral oxygen saturation (rSO2) is linked with blood pressure. This study evaluated the influence of perioperative rSO2 monitoring on the prognosis of ischemic Moyamoya disease (MMD) patients undergoing anastomosis surgery. In this prospective cohort, patients with unilateral ischemic MMD of Suzuki stage ≥3 were included. The decision of rSO2 was made by the clinician and the patient. The rSO2 group maintained intraoperative rSO2 levels through the modulation of blood pressure, inhaled oxygen concentration, carbon dioxide in arterial blood, and red blood cell transfusion. The non-rSO2 group used conventional anesthesia practices. Perioperative mean arterial pressure (MAP), rSO2 values, neurological complications, and postoperative results were assessed. A total of 75 eligible patients were categorized into a rSO2 monitoring group (n = 30) and a non-rSO2 monitoring group (n = 45). For the rSO2 group, the preoperative rSO2 was significantly lower on the affected side (P < 0.05). After anastomosis, this value notably increased (P = 0.01). A moderate relationship was observed between perioperative rSO2 and MAP before, during, and after surgery, with correlation coefficients (r) of 0.536, 0.502, and 0.592 (P < 0.05). Post-surgery MAP levels differed between the groups, with the rSO2 group showing decreased levels compared to pre-surgery and the non-rOS2 group displaying elevated levels. Notably, the rSO2 group reported shorter hospitalizations and decreased neurological complications. Patients with a hypertension history found postoperative MAP influencing hospital stay duration. Perioperative rSO2 surveillance enhanced cerebral perfusion and minimized postoperative complications in ischemic MMD patients. Thus, rSO2 monitoring is advocated for MMD patients undergoing vascular anastomosis.

Arterial blood analysis of healthy residents in Huamachuco, Peru (3,164 m): a cross-sectional study

Background: Given that arterial blood gas is affected by altitude and ethnicity, establishing reliable reference standards for these values requires analysis of arterial blood at different elevations and locations. Our objective was to measure the arterial blood gases of healthy young volunteers in Huamachuco, Peru, at 3,164 m above sea level. This is likely the first study of arterial blood gas analysis of healthy Northern Peruvians living at high altitude. Methods: Healthy residents of Huamachuco were recruited for this cross-sectional convenience sample study and arterial blood was drawn by standard procedures. People with obesity, diabetes, high levels of physical activity and a history of using selected substances were excluded. The samples were analyzed on-site in less than 15 minutes using a Stat Profile Prime CCS analyzer (Nova Biomedical). Results: Data from 46 participants (17 male, 29 female) were included in the study. The median values for arterial blood pH, oxygen, carbon dioxide, ionized calcium, glucose, lactate, hematocrit, oxygen saturation, and bicarbonate were 7.42, 9.3 kPa (70 mmHg), 4.5 kPa (33.5 mmHg), 1.04 mM, 5.19 mM, 1.8 mM, 50 %, 94 %, and 21.6 mM, respectively. We also found a lower prevalence of diabetes among highlanders compared to the Peruvian population. Conclusions: The results determined here were comparable to other results determined at different altitudes in the Americas, although arterial blood oxygen was slightly higher than predicted. These results indicate that Northern Peruvians have an Andean-style adaptation to high altitude.

Cardiorespiratory Effects and Desflurane Requirement in Dogs Undergoing Ovariectomy after Administration Maropitant or Methadone.

General anesthesia for ovariectomy in dogs is based on a balanced anesthesia protocol such as using analgesics along with an inhalant agent. While opioids such as fentanyl and methadone are commonly used for their analgesic potency, other drugs can also have analgesic effects. Maropitant, an antiemetic for dogs and cats, has also been shown to exert analgesic effects, especially on visceral pain. The aim of this study was to compare the cardiorespiratory effects and analgesic properties of maropitant and methadone combined with desflurane in dogs undergoing ovariectomy. Two groups of 20 healthy mixed-breeds bitches undergoing elective ovariectomy received intravenous either maropitant at antiemetic dose of 1 mg kg-1 or methadone at the dose of 0.3 mg kg-1. Cardiorespiratory variables were collected before premedication, 10 min after sedation and during surgery. Recovery quality and postoperative pain were evaluated 15, 30, 60, 120, 240 and 360 min postoperatively. Results showed that maropitant produced analgesia and reduced the requirement of desflurane in amounts similar to those determined by methadone (5.39 ± 0.20% and 4.91 ± 0.26%, respectively) without significant difference, while maintaining heart rate, arterial blood pressure, respiratory rate and carbon dioxide end-tidal partial pressure even at a more satisfactory level. Therefore, maropitant may be recommended as an analgesic drug for abdominal surgery not only in healthy dogs but also in those with reduced cardiorespiratory compensatory capacities or at risk of hypotension, especially when combined with a sedative such as dexmedetomidine.

Evaluation of Diagnostic Accuracy of HACOR Score in Predicting the Success Rate of CPAP in Patients with COVID-19-Induced Hypoxemia

Background: In coronavirus disease 2019 (COVID-19)-associated hypoxemic acute respiratory failure (ARF) may require continuous positive airway pressure (CPAP), and having an appropriate criterion for early diagnosis and prediction of CPAP failure or success can significantly reduce the mortality of these patients. Objectives: This study was conducted to evaluate the diagnostic accuracy of heart rate, acidosis, consciousness, oxygenation, and respiratory rate (HACOR) score in predicting the success rate of CPAP in patients with COVID-19 induced hypoxemia. Methods: This retrospective cross-sectional study was conducted on 200 adult patients aged 63.23 ± 16.23 years with mild to moderate acute respiratory failure (COVID-19), partial pressure of oxygen in arterial blood (PaO2) &lt; 300 mmHg, and partial pressure of carbon dioxide in arterial blood (PaCO2) &lt; 45 mmHg from March 21 to November 21, 2021. The patients were admitted to the respiratory intensive care unit (RICU) of Khatam Al-Anbia (PBUH) Hospital in Shoushtar (southwestern Iran) and were subjected to CPAP for respiratory support. The HACOR score was calculated one hour after the CPAP onset. Data were analyzed by SPSS software (version 22) using Kolmogorov-Smirnov, t-test, pair t-tests, receiver operating characteristic (ROC) curve, sensitivity, specificity, and predictive value indices were used to determine the diagnostic performance of the method. The significance level was set at P ≤ 0.05. Results: The mean HACOR score one hour after the onset of CPAP was 3.50 ± 1.57 (P &lt; 0.001), with a mean of 153.84 ± 27.42 mmHg PaO2/fraction of inspired oxygen (FiO2) ratio (P &lt; 0.001). The cut-off point for the HACOR score one hour after CPAP was 5, which had a sensitivity of 98.06% (94.45% - 99.60%) and a specificity of 83.33% (68.64% - 93.03%). Out of 200 patients, 157 patients (78.5%) had CPAP failure, and 43 patients (21.5%) underwent treatment. The diagnostic accuracy values of the HACOR score and PaO2/FiO2 ratio for predicting CPAP failure were 94.92% and 95.96%, respectively. Conclusions: Our findings support that although the HACOR score had a good diagnostic performance in predicting the success rate of CPAP in patients with COVID-19-induced hypoxemia, PaO2/FiO2 ratio was also shown to be a good predictor of success.

HAEMATOLOGICAL ALTERATIONS IN CALVES WITH ACUTE RESPIRATORY DISTRESS SYNDROME DUE TO ASPIRATION PNEUMONIA: A PROSPECTIVE STUDY

The aim of this prospective study was to investigate the arterial blood gas (ABG) analysis, which is considered the gold standard, and complete blood count (CBC) as a complementary test in neonatal calves with acute respiratory distress syndrome (ARDS) due to aspiration pneumonia. Ten healthy and 20 calves with ARDS due to aspiration of milk/colostrum were enrolled in the study. Clinical examinations were performed at admission. ABG analyses were performed to determine the presence of ARDS and investigate the extent of lung ventilation/damage. CBC analysis was performed from venous blood samples. Heart and respiratory rates and body temperature values were higher in diseased calves than healthy ones (p &lt; 0.000). Arterial pH, partial pressure of oxygen in arterial blood (PaO2) and saturation of oxygen in arterial blood (SaO2) were lower (p &lt; 0.001) in the diseased calves, while partial pressure of carbon dioxide in arterial blood (PaCO2) and lactate levels were higher (p &lt; 0.000) than those in healthy ones. Also, leukocyte (WBC), lymphocyte, monocyte, granulocyte, mean corpuscular volume (MCV), and mean corpuscular haemoglobin (MCH) levels were higher in the diseased calves than the healthy calves (p &lt; 0.032). As a result of the correlation analysis, the only correlation was determined to be between PaO2 and WBC, which was moderately negative. As a result, it was observed that leukocytosis developing in respiratory diseases that cause severe inflammatory processes such as aspiration pneumonia was negatively correlated with PaO2 and could potentially exacerbate hypoxia, and ABG evaluation with CBC could provide useful clinical data in calves with ARDS due to aspiration pneumonia.

Clinical and biostatistical approach to assessing the severity of physical status of patients with combined midface trauma. Part 2

Objective. To develop a method for predicting mortality among patients with combined midface trauma (CMFT).&#x0D; Materials and methods. This study is based on the examination results of 95 patients with CMFT. Depending on the outcome of CMFT, 2 groups of patients were formed: the first group – patients with a favorable outcome (n=50); the second group – patients with an unfavorable outcome (n=45). A group of physiological parameters was measured on the 1st, 3rd, 7th and 14th days of patients’ hospital stays. The creation of the CMFT outcomes predicting method was carried out using factor analysis (principal component method) and discriminant analysis.&#x0D; Results. The CMFT outcomes predicting method has been developed in two variants. The first variant (with parameters of the blood gas test) includes the following parameters: leukocyte index of intoxication according to Ya.Ya. Kalf-Kalifu (LII), blood glucose level, concentration of potassium ions in the blood (K+), international normalized ratio, partial pressure of carbon dioxide in arterial blood, partial pressure of oxygen in arterial blood, measured on the 3rd day after injury, and also the age of the patient, evidence of cardiovascular diseases in patient’s medical history and the occurrence of cerebral edema after the injury. The second variant (without the parameters of the blood gas test) includes the following parameters: absolute number of leukocytes (on the 1st day after injury), LII, K+, blood urea level, absolute number of lymphocytes, measured on the 3rd day after injury, as well as patient’s age, evidence of cardiovascular diseases in patient’s medical history and the occurrence of cerebral edema after injury. The classification accuracy when using the first variant was 100%, the second variant – 98.4%.&#x0D; Conclusions. Taking into account the set of variables included in our study, and based on the results of this study published in the first and in this part of this article, we can conclude that the optimal time point for predicting the CMFT outcomes is the 3rd day after injury. The method for predicting the CMFT short-term outcomes developed in our study can be used in determining the timing for reconstructive surgery as part of the damage control surgery treatment of patients with this pathology.

PULM7: Toward Automatic Control Of Arterial Blood Paco2 Using Artificial Lung Exhaust Gas CO2 As A Surrogate

Purpose: Current clinical Extra Corporeal CO2 removal systems rely on human intervention to adjust to changes in patient activity. Previous studies have investigated the use of capnography for measurement of arterial blood carbon dioxide tension (PaCO2) using artificial lungs (AL). The presented work demonstrates an initial implementation of a controller that directly monitors and regulates PaCO2 using exhaust gas CO2 (EGCO2) measurements. Method: The system operates through two cycles, namely measurement and control. First, the sweep gas flow through the AL is temporarily (~60s) reduced to ~400 mL/min to allow the CO2 concentration on the blood and gas phase of the AL to equilibrate. This allows for EGCO2 (measured via a CO2Meter GC-0017) values to be used as an estimate of PaCO2. The control cycle is based on Proportional-Integral-Derivative (PID) principle wherein the system automatically modulates sweep gas flows through the AL to minimize the difference between the desired PaCO2 and the estimated PaCO2 (i.e., measured EGCO2). Blood samples were intermittently collected at the inlet of the AL to monitor actual PaCO2 (measured via a Radiometer ABL800 Flex blood gas analyzer). The in vitro study setup (Fig. 1) consists of a Novalung iLA oxygenator (main AL) and a Capiox RX25 oxygenator (conditioning AL) connected in parallel to model a typical ECMO circuit. The blood reservoir mimics the blood volume (7 L) while the centrifugal pump simulates cardiac output (fixed at ~5 L/min) of a patient. Blood flow through the main AL (AV shunt) was regulated at ~1 L/min using a Hoffman clamp. CO2 concentration in the sweep gas through the conditioning AL was modulated to simulate metabolic activity. The baseline CO2 concentration measured at the outlet of the conditioning AL that projects reservoir PaCO2 level when the main AL is not operational. The baseline blood concentration was varied between 45 and 90 mmHg representing all levels of normocapnia and hypercapnia. Results: Prior to the controller testing, a feasibility study was performed to determine the accuracy of capnography technique in calculating the PaCO2 using the AL. A total of forty-two blood samples were collected at blood flow rates of 0.5, 0.6 and 1.0 L/min. The results show a good correlation between PaCO2 and EGCO2 (r2=0.824, P<0.001). There was a reasonable degree of agreement between the PaCO2 and EGCO2 with accuracy (bias or mean difference between PaCO2 and EGCO2) of 6.04 mmHg with a precision (95% limits of agreement) of ± 9.62 mmHg (Fig. 2). Despite the limitation of the AL in estimating PaCO2 using EGCO2, the PID controller implementation demonstrated that average reservoir CO2 concentration can be maintained at 44.23 ± 8.7 mmHg for a target PaCO2 of 40 mmHg (Fig. 3),against baseline blood reservoir PaCO2 of 60.76 ± 13.81 mmHg.Figure 1. Image showing in vitro test setup. The bovine blood in the test circuit was anticoagulated (ACT > 1200s) with heparin and maintained at 37°C.Figure 2. a) The regression curve generated between PaCO2 samples and measured EGCO2 b) Agreement between PaCO2 samples and measured EGCO2.Figure 3. a) In vitro test results showing changes in all PaCO2 concentrations in the circuit b) Result summary comparing average reservoir PaCO2 level with target PaCO2

Nichtinvasive Beatmung bei chronisch obstruktiver Lungenerkrankung mit chronischer respiratorischer Insuffizienz

Due to the steadily increasing number of patients with chronic obstructive pulmonary disease (COPD), the number of those with very advanced stages of the disease is also steadily increasing. Particularly in severe COPD, respiratory insufficiency occurs in the course of the disease, which by affection of the respiratory pump can become clinically evident as respiratory failure with subsequent hypercapnia. In chronic hypercapnic insufficiency non-invasive ventilation via face masks is the treatment of choice; however, an improvement of the mortality and prolonged hospitalization-free survival can only be achieved if the ventilation treatment is initiated with the aim of normocapnia or the maximum possible reduction of the partial pressure of carbon dioxide in arterial blood. This high intensity ventilation is now recommended in national and international guidelines and is the current standard treatment in COPD with chronic hypercapnic respiratory insufficiency.

Comment on the article of R. Iu. Ovsiannikov and K. M. Lebedinskii “Correlation between changes in arterial blood oxygen partial pressure, oxygen uptake and carbon dioxide elimination by the lungs with changes in positive end expiratory pressure: a prospe

Comment on the article of R.Iu. Ovsiannikov and K.M. Lebedinskii “Correlation between changes in arterial blood oxygen partial pressure, oxygen uptake and carbon dioxide elimination by the lungs with changes in positive end expiratory pressure: a prospective observational study”