Vital signs of severe COVID-19 patients during inter-hospital helicopter transfer

Background: During the COVID-19 pandemic in The Netherlands, critically ill ventilated COVID-19 patients were transferred not only between hospitals by ambulance but also by the Helicopter Emergency Medical Service (HEMS). To date, little is known about the impact of helicopter transport on critically ill patients and COVID-19 patients in particular. This study was conducted to explore the impact of inter-hospital helicopter transfer on vital signs of mechanically ventilated severe COVID-19 intensive care patients, with special focus on take-off, midflight, and landing.Methods: All ventilated critically ill COVID-19 patients who were transported between April 2020 and June 2021 by the Dutch ‘Lifeliner 5’ HEMS team and who were fully monitored, including noninvasive cardiac output, were included in this study. Three 10-minute timeframes (take-off, midflight and landing) were defined for analysis. Continuous data on the vital parameters heart rate, peripheral oxygen saturation, arterial blood pressure, end-tidal CO2 and noninvasive cardiac output using electrical cardiometry were collected and stored at 1-minute intervals. Data were analydzed for differences over time within the timeframes using 1-way analysis of variance. Significant differences were checked for clinical relevance.Results: Ninety-eight patients were included in the analysis. During take-off, an increase was noticed in cardiac output (from 6.7 to 8.1 Lmin-1; P<0.0001), which was determined by a decrease in systemic vascular resistance (from 1068 to 750 dyne·s·cm−5, P<0.0001) accompanied by an increase in stroke volume (from 92.0 to 110.2 ml, P<0.0001). Other parameters were unchanged during take-off and mid-flight. During landing, cardiac output and stroke volume slightly decreased (from 7.9 to 7.1 Lmin-1, P<0.0001 and from 108.3 to 100.6 ml, P<0.0001, respectively), and total systemic vascular resistance increased (P<0.0001). Though statistically significant, the found changes were small and not clinically relevant to the medical status of the patients as judged by the attending physicians.Conclusions: Interhospital helicopter transfer of ventilated intensive care patients with COVID-19 can be performed safely and does not result in clinically relevant changes in vital signs.This study was assessed by the medical ethical committee Arnhem-Nijmegen, the Netherlands (identifier 2021-7313). The committee waived the need for informed consent. The study was registered at www.trialregister.nl (identifier NL9307).

Esmolol response in septic shock patients in relation to vascular waterfall phenomenon measured by critical closure pressure and mean systemic filling pressure: a prospective observational study

Background Bedside measurements of critical closure pressure (Pcc) and mean systemic circulation filling pressure (Pmsf) were utilized to evaluate the response to esmolol in septic shock patients, in relation to the vascular waterfall phenomenon and body oxygen supply and demand. Methods This prospective observational self-controlled study included patients with septic shock, newly admitted to the intensive care unit, between August 2019 and January 2021. Pcc and Pmsf, along with the heart rate and other hemodynamic indicators were observed and compared before and 1 h after esmolol IV infusion. Results After 24 h of initial hemodynamic optimization, 56 patients were finally enrolled. After start of esmolol infusion, patients had a significant decrease in cardiac index (CI) (4.0 vs. 3.3 L/min/m2, P < 0.001), a significant increase in stroke index (SI) (34.1 vs. 36.6 mL/m2, P < 0.01), and a significant decrease in heart rate (HR) (116.8 vs. 90.6 beats/min, P < 0.001). After 1 h of treatment with esmolol, patients had a significant increase in Pcc (31.4 vs. 36.7 mmHg, P < 0.01). The difference between Pcc and Pmsf before and after treatment was statistically different (4.0 vs. 10.0 mmHg, P < 0.01). After heart rate control with esmolol, the patients had a significant increase in the body circulation vascular resistance indices (RIs) (15.14 vs. 18.25 mmHg/min/m2/L, P < 0.001). There was an increase in ScvO2 in patients after treatment with esmolol, but the difference was not statistically significant (68.4% vs. 69.8%, P > 0.05), while Pcv-aCO2 was significantly lower (6.3 vs. 4.9 mmHg, P < 0.001) and patients had a significant decrease in blood lactate levels (4.0 vs. 3.6 mmol/L, P < 0.05). Conclusion Patients with septic shock whose heart rate is greater than 95 beats/min after hemodynamic optimization were treated with esmolol, which could effectively control heart rate and reduce CI, as well as improve Pcc and increase the difference between Pcc and Pmsf (known as “vascular waterfall” phenomenon), without affecting MAP, CVP, Pmsf and arteriovenous vascular resistance, and improve the balance of oxygen supply and demand in the body.

Relationship Between Left Ventricular Ejection Fraction Variation and Systemic Vascular Resistance: A Prospective Cardiovascular Magnetic Resonance Study

Introduction: This cardiovascular magnetic resonance (CMR) study aims to determine whether changes in systemic vascular resistance (SVR), obtained from CMR flow sequences, might explain the significant long-term changes in left ventricular (LV) ejection fraction (EF) observed in subjects with no cardiac disease history.Methods: Cohort subjects without any known cardiac disease but with high rates of hypertension and obesity, underwent CMR with phase-contrast sequences both at baseline and at a median follow-up of 5.2 years. Longitudinal changes in EF were analyzed for any concomitant changes in blood pressure and vascular function, notably the indexed SVR given by the formula: mean brachial blood pressure / cardiac output x body surface area.Results: A total of 118 subjects (53 ± 12 years, 52% women) were included, 26% had hypertension, and 52% were obese. Eighteen (15%) had significant EF variations between baseline and follow-up (7 increased EF and 11 decreased EF). Longitudinal changes in EF were inversely related to concomitant changes in mean and diastolic blood pressures (p = 0.030 and p = 0.027, respectively) and much more significantly to SVR (p &lt; 0.001). On average, these SVR changes were −8.08 ± 9.21 and +8.14 ± 8.28 mmHg.min.m2.L−1, respectively, in subjects with significant increases and decreases in EF, and 3.32 ± 7.53 mmHg.min.m2.L−1 in subjects with a stable EF (overall p &lt; 0.001).Conclusions: Significant EF variations are not uncommon during the long-term CMR follow-up of populations with no evident health issues except for uncomplicated hypertension and obesity. However, most of these variations are linked to SVR changes and may therefore be unrelated to any intrinsic change in LV contractility. This underscores the benefits of specifically assessing LV afterload when EF is monitored in populations at risk of vascular dysfunction.Clinical Trial Registration:ClinicalTrials.gov, identifier: NCT01716819 and NCT02430805.

ANTAGONISM IN SYSTEM REGULATION ARTERIAL PRESSURE And ITS CHANGE after THERAPY NICERGOLINE

By the method of fractional trends, when analyzing the dynamic series of blood pressure (АД), an antagonism between the cardiac output block (CB) and the peripheral vascular resistance block (СПС) was revealed in the patient, after 12 weeks of nicergoline therapy, at the 1-3 hierarchical level of systemic regulation. At the subordinate 4-6 levels of the hierarchy, the phenomenon of antagonism was also revealed. When regulating systolic (САД) and diastolic (ДАД) blood pressure, this method revealed that nicergoline has a greater effect on the regulation of ДАД.

Circulating Interleukin-7 in Human Pulmonary Arterial Hypertension

Objectives: Interleukin-7 (IL-7) secures B cell maturation, regulatory T and natural killer (NK) cell survival, and homeostasis, all of which are important for beneficial immunomodulation in pulmonary arterial hypertension (PAH). However, the role and potential impact of IL-7, VEGF-C and the vascular injury markers ICAM-1, and VCAM-1 on the pathobiology and severity of PAH is unknown.Methods: EDTA blood was collected during cardiac catheterization from the superior vena cava (SVC), pulmonary artery (PA), and ascending aorta (AAO) in children with pulmonary hypertension (PH) [n = 10; 9.1 (3.9–18.5) years] and non-PH controls [n = 10; 10.5 (2.0–17.3) years]. Compartment-specific plasma concentrations of IL-7, VEGF-C, aldosterone, ICAM-1, and VCAM-1 were determined using Meso Scale Discovery's multi array technology and the LIAISON Aldosterone Assay.Results: Children with PH had approximately 50% lower IL-7 (p &lt; 0.01) and 59% lower VEGF-C plasma levels (p &lt; 0.001) in the SVC, PA, and AAO versus non-PH controls. IL-7 and VEGF-C concentrations negatively correlated with the pulmonary vascular resistance (PVR)/systemic vascular resistance (SVR) ratio (rho = −0.51 and r = −0.62, respectively). Central-venous IL-7 strongly positively correlated with VEGF-C (r = 0.81). Most patients had a step down in ICAM-1 and VCAM-1 plasma concentrations across the pulmonary circulation and both ICAM-1 and VCAM-1 transpulmonary gradients negatively correlated with invasive hemodynamics.Conclusion: This manuscript is the first report on decreased circulating IL-7 and VEGF-C plasma concentrations in human PAH and their inverse correlations with invasive surrogates of PAH severity. Additional and larger studies are needed to explore the role of the immune-modulatory IL-7 and VEGF-C in pediatric and adult PAH.

Effect of Repeated Exposure to Contrasting Temperatures on the Body of Working Age Men with Different Types of Autonomic Regulation

The aim of this paper was to study changes in the haemodynamic and psychophysiological parameters of working age men as a result of repeated exposure to contrasting temperatures, depending on the type of autonomic regulation. Materials and methods. The research involved 14 men (aged 34.77 ± 5.66 years; office workers) divided into two groups according to Kérdö index: those with the sympathetic (n = 8) and parasympathetic (n = 6) types of self-regulation. Cold conditioning followed a certain plan of exposure to contrasting temperatures. The haemodynamic and psychophysiological parameters as well as adaptive potential were assessed 20 minutes before and 20 minutes after the exposure (alternating temperature cycles). We examined the following parameters: heart rate, systolic and diastolic blood pressure, pulse and mean arterial pressure, stroke volume, cardiac output, vascular resistance, and adaptive potential according to Baevsky. Integral psychophysiological parameters were determined using the Lüscher express method. Results. Subjects with predominance of sympathetic regulation both before and after the exposure to contrasting temperatures had higher values of heart rate and cardiac output and lower vascular resistance than the parasympathicotonic group. Individuals with predominance of parasympathetic regulation showed decreased cardiac output and a significant increase in vascular resistance after the exposure compared with the initial data. We found statistically significant differences in the integral parameters “heteronomy/autonomy” and “balance of personal traits” between the groups under study before the conditioning procedures. The research indicates that repeated exposure to contrasting temperatures not only affects the haemodynamic parameters, but also changes the psychophysiological parameters, motivated behaviour in particular. For citation: Fisher T.A., Kolyvanova S.S. Effect of Repeated Exposure to Contrasting Temperatures on the Body of Working Age Men with Different Types of Autonomic Regulation. Journal of Medical and Biological Research, 2021, vol. 9, no. 4, pp. 394–404. DOI: 10.37482/2687-1491-Z077

342 Cardiorespiratory fitness and systemic vascular resistance: oxygen pressure as a novel marker of peripheral vascular response during cardiopulmonary exercise testing

Aims The key role of systemic vascular resistance (SVR) in cardiovascular performance during exercise has been invasively demonstrated, however no data have been non-invasively obtained by analysing SVR response using cardiopulmonary exercise testing (CPET). To investigate the relationship between SVR at peak, maximum oxygen uptake (VO2 peak), and its determinants using CPET. Methods and results 1130 consecutive subjects were enrolled; according to physiology, SVR was determined as the ratio between mean arterial pressure (MAP) and cardiac output (CO). A novel parameter, named oxygen pressure (MAP peak/VO2 peak) was also created. Mean age was 61 ± 12 years and male gender was prevalent (61%); 66% of patients had arterial hypertension, 74% dyslipidaemia, 19% diabetes, 20% had smoking habit, and 26% previous history of cardiovascular (CV) disease. Significant inverse correlations between SVR peak and VO2/kg peak (P &lt; 0.001), oxygen pulse (P &lt; 0.001), CV efficiency (P &lt; 0.001), chronotropic response (P &lt; 0.001), and oxygen uptake exaction slope (P &lt; 0.001) were found. Moreover, positive correlation between SVR peak and VE/VCO2 slope (P &lt; 0.001) was observed. After multivariate analysis, the inverse correlation between peak SVR and peak VO2 remained significant (P &lt; 0.001). Similar results were found considering oxygen pressure. Conclusions Low values of SVR at peak exercise, non-invasively evaluated with CPET, are associated with high levels of cardiorespiratory fitness. Oxygen pressure may represent a novel and simple CPET marker of peripheral vascular response to exercise, thereby representing a promising field of research in exercise medicine.

63 Peripheral endothelial function in patients affected by pulmonary hypertension. Relationship between endothelial function, haemodynamic parameters, and therapy response

Aims Pulmonary hypertension (PH) is defined as a mean pulmonary arterial pressure (mPAP) of 25 mmHg or greater at rest, confirmed by right heart catheterization (RHC). The World Health Organization has classified PH into five clinical subgroups. Pulmonary arterial hypertension (PAH) (group 1) is characterized by loss and obstructive remodelling of the pulmonary vascular bed. These patients are characterized haemodynamically by the presence of precapillary PH, defined as an mPAP of 25 mm Hg or greater, pulmonary artery wedge pressure (PAWP) of 15 mm Hg or less, and pulmonary vascular resistance (PVR) of three Wood units (WU) or greater. Pulmonary hypertension due to left-sided heart disease (LHD) (PH-LHD) (group 2) occurs in HF. Patients with PH-LHD usually have isolated postcapillary PH (PAWP &gt;15 mm Hg and PVR &lt;3 WU), although some of them have combined postcapillary and precapillary PH (PAWP &gt;15 mm Hg and PVR ≥3 WU). PH due to chronic lung disease (CLD) (PH-CLD) and/or hypoxia (group 3) can occur in many lung diseases. These patients have precapillary PH. Chronic thromboembolic PH (CTEPH) (group 4) is characterized by obstruction of the pulmonary vasculature by organized thromboembolic material and vascular remodelling, resulting from prior pulmonary embolism. Patients with unclear and/or multifactorial mechanisms are listed as group 5. Specific pulmonary vasodilators are approved only in PAH patients. While research was predominantly focused on pulmonary vasculature, little is known about the peripheral endothelial damage in different vascular beds in PH patients. To evaluate the relationship between the peripheral endothelial function and the haemodynamic parameters, in order to provide a non-invasive method for the indirect evaluation of mean pulmonary pressure and vascular resistance, to predict if the PH is a precapillary or postcapillary, to select more accurately the patients who should undergo RHC. Moreover, we investigate if there is a possible correlation between endothelial dysfunction and response to specific PH therapies. Methods and results Patients with suspected PH, based on symptoms, medical history, and clinics will undergo physical examination, ECG, echocardiography, and RHC. In all patients, endothelial function was assessed by FMD. Medical history, heart rate, systolic blood pressure, body mass index, WHO functional class, and medications were recorded. All patients underwent blood analysis, erythrocyte sedimentation rate (ERS), high sensitivity C-reactive protein (CRP), and NT-proBNP levels were assayed. Increased peripheral endothelial dysfunction in patients with precapillary PH, with a linear correlation between endothelium dysfunction and increased PVR at the right catheterization. To differentiate pre and post capillary PH forms by cut-off values of the FMD. The degree of endothelial dysfunction could be a marker of therapy response. Sequential combination therapy in the pre-capillary PH forms could be the one with a worst endothelial response than up-front combination therapy.