Effects of pulsed inhaled nitric oxide delivery on the distribution of pulmonary perfusion in spontaneously breathing and mechanically ventilated anesthetized ponies

OBJECTIVE To measure changes in pulmonary perfusion during pulsed inhaled nitric oxide (PiNO) delivery in anesthetized, spontaneously breathing and mechanically ventilated ponies positioned in dorsal recumbency. ANIMALS 6 adult ponies. PROCEDURES Ponies were anesthetized, positioned in dorsal recumbency in a CT gantry, and allowed to breathe spontaneously. Pulmonary artery, right atrial, and facial artery catheters were placed. Analysis time points were baseline, after 30 minutes of PiNO, and 30 minutes after discontinuation of PiNO. At each time point, iodinated contrast medium was injected, and CT angiography was used to measure pulmonary perfusion. Thermodilution was used to measure cardiac output, and arterial and mixed venous blood samples were collected simultaneously and analyzed. Analyses were repeated while ponies were mechanically ventilated. RESULTS During PiNO delivery, perfusion to aerated lung regions increased, perfusion to atelectatic lung regions decreased, arterial partial pressure of oxygen increased, and venous admixture and the alveolar-arterial difference in partial pressure of oxygen decreased. Changes in regional perfusion during PiNO delivery were more pronounced when ponies were spontaneously breathing than when they were mechanically ventilated. CLINICAL RELEVANCE In anesthetized, dorsally recumbent ponies, PiNO delivery resulted in redistribution of pulmonary perfusion from dependent, atelectatic lung regions to nondependent aerated lung regions, leading to improvements in oxygenation. PiNO may offer a treatment option for impaired oxygenation induced by recumbency.

Predictive value of chest HRCT for survival in idiopathic pulmonary arterial hypertension

Background Little attention has been paid to chest high resolution computed tomography (HRCT) findings in idiopathic pulmonary arterial hypertension (IPAH) patients so far, while a couple of small studies suggested that presence of centrilobular ground-glass opacifications (GGO) on lung scans could have a significant negative prognostic value. Therefore, the aims of the present study were: to assess frequency and clinical significance of GGO in IPAH, and to verify if it carries an add-on prognostic value in reference to multidimensional risk assessment tool recommended by the 2015 European pulmonary hypertension guidelines. Methods Chest HRCT scans of 110 IPAH patients were retrospectively analysed. Patients were divided into three groups: with panlobular (p)GGO, centrilobular (c)GGO, and normal lung pattern. Association of different GGO patterns with demographic, functional, haemodynamic, and biochemical parameters was tested. Survival analysis was also performed. Results GGO were found in 46% of the IPAH patients: pGGO in 24% and cGGO in 22%. Independent predictors of pGGO were: positive history of haemoptysis, higher number of low-risk factors, and lower cardiac output. Independent predictors of cGGO were: positive history of haemoptysis, younger age, higher right atrial pressure, and higher mixed venous blood oxygen saturation. CGGO had a negative prognostic value for outcome in a 2-year perspective. This effect was not seen in the longer term, probably due to short survival of cGGO patients. Conclusions Lung HRCT carries a significant independent prognostic information in IPAH, and in patients with cGGO present on the scans an early referral to lung transplantation centres should be considered.

Diagnostic value of right heart and pulmonary artery catheterization in patients with suspected pulmonary hypertension. Part 2. Invasive study of parameters of hemodynamics and oxygen transport

The aim – evaluate the parameters of pulmonary and systemic hemodynamics obtained in patients with various forms of pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) in Ukraine.Materials and methods. The study included 195 patients: IPAH was in 68 patients; PAH associated with connective tissue diseases (CTD) – in 21 patients; PAH associated with HIV infection – in 4 patients; PAH associated with portal hypertension (PH) – in 4 patients; PAH associated with congenital heart disease – in 25 patients; CTEPH – in 51 patients, pulmonary hypertension (PH) associated with left heart disease (LHC) – in 5 patients and 17 patients who were excluded from the diagnosis of PH. From 2014 to 2019, these patients underwent 220 procedures of right heart catheterization (RHC) in accordance with current European Guidelines. Also, all patients underwent echocardiographic examination and determined the gas composition of blood and indicators of acid-base balance using the ABL 735 analyzer, calculated the parameters of the affinity of hemoglobin to oxygen (p50).Results and discussion. The lowest level of arterial blood oxygen saturation was in the group of patients with PH due to LHD – 88.9 % (p<0.05); in other groups it averaged 94–97 %. The oxygen content in arterial blood was the lowest in the group of patients with PH due to LHD – 15.7 ml/L (p<0.05); in other groups this indicator was equal to 17.4–18.7 ml/L. The lowest oxygen saturation of mixed venous blood (SvO2) was in the PAH group associated with HIV – 58 % (p<0.05), and close to critical (< 65 %) SvO2 level was observed in the IPAH group – 66.3 %. CTEPH – 66.0 %. The highest level of this indicator was in the PAH group associated with portal hypertension – 81.1 %. The arterio-venous difference was highest in the PAH associated with HIV group – 5.6 ml/L, and the smallest in the PAH associated with PH group – 2 ml/L. On the other hand, the oxyhemoglobin dissociation curve was almost normal in all groups, except for the group of patients with PAH associated with portal hypertension.Conclusions. The most severe disorders of hemodynamics and oxygen transport were observed in the group of PAH patients associated with HIV compared with other forms of PAH and CTEPH. The IPAH and CTEPH groups were similar in terms of hemodynamics, despite a different pathophysiological mechanism. In the group of patients with PAH associated with CTD, the results of the RHC were slightly better than in the group of patients with IPAH, reflecting that the hemodynamic component is not the leading one for prognosis in these patients. Also, the performance of the right ventricle was significantly higher in patients with PAH compared with the group without PH.

Relationship between Ag-NORs and T Lymphocyte Subsets in Children with Epilepsy

With the acceleration of the pace of life, the number of children with epilepsy is increasing. This study was to investigate the relationship between Ag-NORs and T lymphocyte subsets in children with epilepsy. In the morning, 3ml of elbow vein blood was collected from epileptic children on an empty stomach. After standing at room temperature for 0.3-1 hour, the serum was centrifuged (2000 rpm, 4 minutes). 3 ml of mixed venous blood was collected in EDTA-K2 vacuum container. The sample was taken out within 5 hours after staining. 30 n I of Itcite reagentand 30 n I of anticoagulant were put into TruCount tube and mixed evenly. Then flow cytometry was used for detection, and facscomp software was used for automatic inspection and calibration. In the same way, the automatic analysis software muitiset was used to obtain 20000 white blood cells, count 8000-10000 lymphocytes automatically, and calculate CD4 + T lymphocytes, CD8 + T lymphocytes and CD4 + / CD8 + ratio. Ag-NORs detection: under aseptic conditions, 0.5ml anticoagulant blood was added into the medium flask containing rpm-1640 and incubated in the incubator at 37°C for 72 hours. After mixing the cell suspension at room temperature, put it into a 10ml glass tube, heat it and dry it. Wait until the temperature of the water solution tank rises to 80-90 °C, and then put aluminum plate on it. The staining was placed under the microscope on the stage, and the image was adjusted to make the image analysis program effective. The ratio of nuclear area to nuclear silver staining area of 30 lymphocytes was counted. This ratio reflects the content of Ag-NORs in the nucleolar forming region of T lymphocytes. The ratio of Ag-NORs area to nuclear area was 0.32 ± 0.03, 0.38 ± 0.03 and 0.46 ± 0.03, respectively. This study is helpful to provide guidance for the treatment of epilepsy in children.

Сomputed tomography in assessing the severity of patients with chronic thromboembolic pulmonary hypertension

Objective. To evaluate the role of computed tomography in the assessment of chronic thromboembolic pulmonary hypertension (CTEPH) severity. Design and methods. We included 41 patients. Chest dual-energy CT-computed tomographic angiography was performed according to the standard protocol and in some cases Dual Energy mode was used. The patients were divided into 2 groups: with proximal and distal types of pulmonary artery lesions. Results. Quanadli index and Score index showed a significant negative correlation with the value of cardiac output (CO) (r = –0,591, p < 0,05; r = –0,531, p < 0,001, respectively), mixed venous blood saturation (SvO2) (r = –0,457, p = 0,065; r = –0,595, p < 0,001, respectively). For the Score index, significant negative correlations were established with both the CO value: r = –0,531, p < 0,001, the SvO2 r = –0,595, p < 0,001, and with the N-terminal pro-B type natriuretic peptide (NTproBNP) value (r = –0,537, p = 0,003). Correlations are also found in the analysis within the compared groups. The Quanadli index correlated with the mean pressure in the pulmonary artery in the group with the proximal type of lesion (r = 0,825, p = 0,012). Pulmonary artery aneurysms were detected in 39 % (n = 16) patients. There was a positive correlation between the presence of a pulmonary artery aneurysm and the functional class of CTEPH (r = 0,526, p = 0,007) in patients with the distal lesion. Conclusions. Quanadli and Score indices are promising tools for CTEPH severity assessment.

The effect of hypocapnia on systemic perfusion in patients with single ventricle after surgery

The objective: the aim of the study was to identify the relationship between arterial hypocapnia and systemic hypoperfusion in newborns with single ventricular physiology after hemodynamic correction of congenital heart disease. Subjects and methods. 125 newborns with congenital heart defects operated from 2014 to 2018 were examined retrospectively. Arterial and central venous blood gases were collected in the postoperative period. A total of 670 pairs of laboratory results were selected.Results. Based on the presence/absence of hypocapnia (PaCO2 less than 35 mm Hg), 2 groups were formed. Group G-0 (the hypocapnic variant of the single-ventricular circulation) comprised 44 observations. Group G-1 (PaCO2 more than 35 mm Hg) included 40 observations. In 32 (38%) cases the level of systemic perfusion was within the normal range, in 52 (62%) cases, systemic hypoperfusion was detected. In samples corresponding to Group G-1, signs of DOS were observed in 20 cases. The study showed that the most pronounced intergroup difference in parametric data was observed among indicators reflecting oxygen consumption and, as a consequence, the system flow rate (РO2 in mixed venous blood, saturation in mixed venous blood, arterio-venous difference in saturation, O2 content in venous blood, O2 extraction ratio, arterio-venous difference in РCO2). In addition, the HF markers such as arterio-venous difference in saturation, O2 extraction ratio, arterio-venous difference in РCO2 had a strong correlation with the signs of systemic hypoperfusion. In the hypocapnic group, the tendency for more pronounced desaturation of venous blood was determined, and a higher arterio-venous difference in saturation, O2 content in venous blood, O2 extraction ratio, and arterio-venous difference in РCO2 parameters were also noted.Conclusions. Arterial hypocapnia may be a sign of pulmonary overflow and reduction of systemic blood flow in newborns with single ventricular physiology, after hemodynamic correction of congenital heart disease. When managing newborns with parallel circulation, hypocapnia should be avoided as a factor contributing to the redistribution of blood flow from left to right and the development of systemic hypoperfusion.

Maximal Fat Oxidation: Comparison between Treadmill, Elliptical and Rowing Exercises

Fat oxidation during exercise is associated with cardio-metabolic benefits, but the extent of which whole-body exercise modality elicits the greatest fat oxidation remains unclear. We investigated the effects of treadmill, elliptical and rowing exercise on fat oxidation in healthy individuals. Nine healthy males participated in three, peak oxygen consumption tests, on a treadmill, elliptical and rowing ergometer. Indirect calorimetry was used to assess maximal oxygen consumption (V̇O2peak), maximal fat oxidation (MFO) rates, and the exercise intensity MFO occurred (Fatmax). Mixed venous blood was collected to assess lactate and blood gases concentrations. While V̇O2peak was similar between exercise modalities, MFO rates were higher on the treadmill (mean ± SD; 0.61 ± 0.06 g·min-1) compared to both the elliptical (0.41 ± 0.08 g·min-1, p = 0.022) and the rower (0.40 ± 0.08 g·min-1, p = 0.017). Fatmax values were also significantly higher on the treadmill (56.0 ± 6.2 %V̇O2peak) compared to both the elliptical (36.8 ± 5.4 %V̇O2peak, p = 0.049) and rower (31.6 ± 5.0 %V̇O2peak, p = 0.021). Post-exercise blood lactate concentrations were also significantly lower following treadmill exercise (p = 0.021). Exercising on a treadmill maximizes fat oxidation to a greater extent than elliptical and rowing exercises, and remains an important exercise modality to improve fat oxidation, and consequently, cardio-metabolic health.

SOFA Score, Hemodynamics and Body Temperature Allow Early Discrimination between Porcine Peritonitis-Induced Sepsis and Peritonitis-Induced Septic Shock

Porcine model of peritonitis-induced sepsis is a well-established clinically relevant model of human disease. Interindividual variability of the response often complicates the interpretation of findings. To better understand the biological basis of the disease variability, the progression of the disease was compared between animals with sepsis and septic shock. Peritonitis was induced by inoculation of autologous feces in fifteen anesthetized, mechanically ventilated and surgically instrumented pigs and continued for 24 h. Cardiovascular and biochemical parameters were collected at baseline (just before peritonitis induction), 12 h, 18 h and 24 h (end of the experiment) after induction of peritonitis. Analysis of multiple parameters revealed the earliest significant differences between sepsis and septic shock groups in the sequential organ failure assessment (SOFA) score, systemic vascular resistance, partial pressure of oxygen in mixed venous blood and body temperature. Other significant functional differences developed later in the course of the disease. The data indicate that SOFA score, hemodynamical parameters and body temperature discriminate early between sepsis and septic shock in a clinically relevant porcine model. Early pronounced alterations of these parameters may herald a progression of the disease toward irreversible septic shock.

Influence of blood Po2 on the stability of agitated saline contrast

Hyperoxic blood has a small stabilizing effect on agitated saline contrast compared with mixed venous blood, lending support to studies that show the reversal of exercise-induced blood flow through intrapulmonary arteriovenous anastomoses (Q̇IPAVA) with hyperoxia. These data support the possible presence of a local O2-dependent regulatory mechanism within the pulmonary vasculature that may play a role in Q̇IPAVA regulation.