Non-invasive Cardiac Output Monitoring Research Articles

Abstract P419: First-Trimester Maternal Hemodynamics In Patients With Or Without Chronic Hypertension Using USCOM (ultrasound Cardiac Output Monitor), A Non-invasive And Quantitative Method.

Objective: We aim to investigate maternal hemodynamics at 10-14 weeks of gestation among patients with and without chronic hypertension, utilizing USCOM®, a non-invasive cardiac output monitor. Methods: A prospective pilot study was conducted for women with singleton pregnancies. Independent T, Mann-Whitney U, and Chi-square tests were used to analyze cardiovascular parameters via Doppler waveform. Results: Thirteen pregnant women with preexisting hypertension and no other medical comorbidities were selected, and 26 controls were matched based on maternal age, ethnicity, and BMI in a ratio of 1:2. Six patients with chronic hypertension were on anti-hypertensive medications. Tables 1 and 2 present each respective group's basic demographic and hemodynamic characteristics. Conclusion: Despite no differences in BP, our study revealed significant hemodynamic changes in chronic hypertensive patients in the first trimester. Chronic hypertensive patients might have pre-existing pathological cardiovascular adaptation in early pregnancy, potentially compromising perinatal outcomes.

Assessing Fluid Responsiveness Using Noninvasive Hemodynamic Monitoring in Pediatric Shock: A Review

AbstractNoninvasive hemodynamic monitoring devices have been introduced to better quantify fluid responsiveness in pediatric shock; however, current evidence for their use is inconsistent. This review aims to examine available noninvasive hemodynamic monitoring techniques for assessing fluid responsiveness in children with shock. A comprehensive literature search was conducted using PubMed and Google Scholar, examining published studies until December 31, 2022. Articles were identified using initial keywords: [noninvasive] AND [fluid responsiveness]. Inclusion criteria included age 0 to 18, use of noninvasive techniques, and the emergency department (ED) or pediatric intensive care unit (PICU) settings. Abstracts, review papers, articles investigating intraoperative monitoring, and non-English studies were excluded. The methodological index for nonrandomized studies (MINORS) score was used to assess impact of study bias and all study components were aligned with Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Our review yielded 1,353 articles, 17 of which met our inclusion criteria, consisting of 618 patients. All were prospective observational studies performed in the ED (n = 3) and PICU (n = 14). Etiologies of shock were disclosed in 13/17 papers and consisted of patients in septic shock (38%), cardiogenic shock (29%), and hypovolemic shock (23%). Noninvasive hemodynamic monitors included transthoracic echocardiography (TTE) (n = 10), ultrasonic cardiac output monitor (USCOM) (n = 1), inferior vena cava ultrasonography (n = 2), noninvasive cardiac output monitoring (NICOM)/electrical cardiometry (n = 5), and >2 modalities (n = 1). To evaluate fluid responsiveness, most commonly examined parameters included stroke volume variation (n = 6), cardiac index (CI) (n = 6), aortic blood flow peak velocity (∆V peak) (n = 3), and change in stroke volume index (n = 3). CI increase >10% predicted fluid responsiveness by TTE in all ages; however, when using NICOM, this increase was only predictive in children >5 years old. Additionally, ∆SV of 10 to 13% using TTE and USCOM was deemed predictive, while no studies concluded distensibility index by transabdominal ultrasound to be significantly predictive. Few articles explore implications of noninvasive hemodynamic monitors in evaluating fluid responsiveness in pediatric shock, especially in the ED setting. Consensus about their utility remains unclear, reiterating the need for further investigations of efficacy, accuracy, and applicability of these techniques.

Noninvasive Cardiac Output Monitoring (NICOM) in the Critically Ill Patient Undergoing Endotracheal Intubation: A Prospective Observational Study.

Background: Cardiovascular instability occurring during endotracheal intubation (ETI) in the critically ill is a commonly recognized phenomenon. However, this complication has not been evaluated in terms of the physiological cause (ie, decreased preload, contractility, or afterload) leading to the instability. Thus, the aim of the current investigation was to describe the hemodynamics occurring during ETI with noninvasive physiologic monitoring and to collect preliminary data on the hemodynamic effects of induction agents and positive pressure ventilation. Methods: A multicenter prospective study enrolling adult (≥18 years) critically ill patients undergoing ETI with noninvasive cardiac output monitoring in a medical/surgical intensive care unit from June 2018 to May 2019 was conducted. This study used the Cheetah Medical noninvasive cardiac output monitor to collect hemodynamic data during the peri-intubation period. Additional data collected included baseline characteristics such as illness severity, peri-intubation pharmacologic administration, and mechanical ventilation settings. Results: From the original 27 patients, only 19 (70%) patients had complete data and were included in the final analysis. Propofol was the most common sedative 8 (42%) followed by ketamine 6 (32%) and etomidate 5 (26%). Patients given propofol demonstrated a decrease in total peripheral resistance index (delta change [dynes × s/cm-5/m2]: -2.7 ± 778.2) but stabilization in cardiac index (delta change (L/min/m2]: 0.1 ± 1.5) while etomidate and ketamine demonstrated increases in total peripheral resistance index (etomidate delta change [dynes × s/cm-5/m2]: 302.1 ± 414.3; ketamine delta change [dynes × s/cm-5/m2]: 278.7 ± 418.9) but only etomidate resulted in a decrease in cardiac index (delta change [L/min/m2]: -0.3 ± 0.5). Positive pressure ventilation resulted in minimal changes to hemodynamics during ETI. Conclusions: The current study demonstrates that although propofol administration leads to a decrease in total peripheral resistance index, cardiac index is maintained while etomidate leads to a decrease in cardiac index with both etomidate and ketamine increasing total peripheral resistance index. These hemodynamic profiles are minimally affected by positive pressure ventilation. Study registration: ClinicalTrials.gov ID, NCT03525743.

Trainability for cardiopulmonary fitness is low in patients with peripheral artery disease.

In patients with peripheral arterial disease (PAD), exercise therapy is recommended to relieve leg symptoms, as noted in the 2016 AHA/ACC and 2017 ESC/ESVS guidelines. We assessed the trainability for cardiopulmonary fitness (CPF) and quality of life (QOL); three distinct patient types, namely, PAD, heart failure (HF), and stroke, were compared. This is a multicentre, retrospective analysis of prospectively collected data from three clinical studies. Data collected from 123 patients who completed 36 sessions of supervised aerobic training of moderate intensity were analysed, with 28 PAD, 55 HF, and 40 stroke patients totalling 123. Before and after training, cardiopulmonary exercise testing with non-invasive cardiac output monitoring and QOL evaluation using a 36-Item Short Form Survey (SF-36) were performed. Non-response was defined as a negative change in the post-training value compared with that in the pre-training value. The result showed an improvement in CPF in all three groups. However, cardiorespiratory fitness (CRF) increased by a lesser extent in the PAD group than in the HF and stroke groups; the physical and mental component scores (MCS) of SF-36 exhibited a similar pattern. Non-response rates of peak V˙O2, oxygen uptake efficiency slope, and MCS were higher in the PAD group. In the PAD group, non-responders regarding peak V˙O2 had a higher pulse wave velocity than responders. In patients with PAD following exercise therapy, CRF and QOL improved to a lesser extent on average; their non-response rate was also higher compared with that of HF or stroke patients. Therefore, a higher dose of exercise might be needed to elicit adaptation in PAD patients, especially those with high pulse wave velocity.

Advantages and limitations of noninvasive devices for cardiac output monitoring: a literature review.

Individualized hemodynamic optimization often requires cardiac output monitoring, mostly for goal-directed therapy in the operating room and fluid responsiveness assessment in the intensive care unit. Different technologies for noninvasive cardiac output determination have become available over the recent years. It is therefore crucial for care providers to be made aware of the advantages and limitations of those different devices for an appropriate use at the bedside. Nowadays, different noninvasive technologies exist, each with their advantages and limitations, but none are considered interchangeable with bolus thermodilution. Different clinical studies however, emphasize that the trending ability of such devices allows to guide decisions from care providers, and that their use may be associated with improved prognosis, especially in the operating room. Recent studies have also reported their potential use for hemodynamic optimization in specific populations. Noninvasive cardiac output monitoring may have a clinical impact on patient outcomes. Further studies are required to evaluate their clinical relevance, notably in the intensive care unit. Noninvasive monitoring opens up the possibility for hemodynamic optimization in specific or low-risk populations, the benefit of which remains to be assessed.

Capnodynamics - noninvasive cardiac output and mixed venous oxygen saturation monitoring in children.

Hemodynamic monitoring in children is challenging for many reasons. Technical limitations in combination with insufficient validation against reference methods, makes reliable monitoring systems difficult to establish. Since recent studies have highlighted perioperative cardiovascular stability as an important factor for patient outcome in pediatrics, the need for accurate hemodynamic monitoring methods in children is obvious. The development of mathematical processing of fast response mainstream capnography signals, has allowed for the development of capnodynamic hemodynamic monitoring. By inducing small changes in ventilation in intubated and mechanically ventilated patients, fluctuations in alveolar carbon dioxide are created. The subsequent changes in carbon dioxide elimination can be used to calculate the blood flow participating in gas exchange, i.e., effective pulmonary blood flow which equals the non-shunted pulmonary blood flow. Cardiac output can then be estimated and continuously monitored in a breath-by-breath fashion without the need for additional equipment, training, or calibration. In addition, the method allows for mixed venous oxygen saturation (SvO2) monitoring, without pulmonary artery catheterization. The current review will discuss the capnodyamic method and its application and limitation as well as future potential development and functions in pediatric patients.

Comparison of a noninvasive cardiac output monitor (NICOM) with simultaneous transthoracic echocardiography in pregnant women

Comparison of a noninvasive cardiac output monitor (NICOM) with simultaneous transthoracic echocardiography in pregnant women

The Value of Noninvasive Continuous Cardiac Output Monitoring in Assessment of Hemodynamic Status in Critically Ill Children

Access to reliable, rapid, and continuous hemodynamic monitoring parameters is essential for early diagnosis and prompt treatment of hemodynamic disorders in critically ill children. The aim of this observational study was to compare the accuracy of continuous non-invasive cardiac output monitoring (NICCOMO) device data with transthoracic echocardiography (TTE) and inferior vena cava (IVC) ultrasound findings in assessing cardiac output (C.I), circulatory fluid adequacy, and finally Determination of hemodynamic status in patients with Critical conditions hospitalized in the Pediatric Intensive Care Unit (PICU). In this observational study, forty-four critically ill children that were admitted to PICU were evaluated. We used NICCOMO, TTE, and IVC ultrasonography at the same time in critical patients. The association between NICCOMO parameters and echocardiogram cardiac index and IVC quality in ultrasound is compared. The agreement between CI measured by TTE and NICCOMO was assessed using the Bland-Altman analysis method. NICCOMO is not a reliable instrument for determining CI in children with an unstable hemodynamic status. However, the parameters of this device are reliable in assessing the patient's hemodynamic status. Findings showed that 90% of patients in the normal hemodynamic state in NICCOMO have SVR. I in the normal range (P<0.001), and all cases in hypervolemic state had volume overload IVC in ultrasonography analysis. Noninvasive continuous cardiac output monitoring could be used to estimate unstable patients’ hemodynamic status in the initial stages for making timely treatment-related decisions, but its use for accurate cardiac index measurement is not reliable in all cases.

Can passive leg raise predict the response to fluid resuscitation in ED?

ObjectivePassive leg raise (PLR) can be used as a reversible preload challenge to stratify patients according to preload response. We aim to evaluate the accuracy of PLR, monitored by a non-invasive cardiac output monitor in predicting to response to fluid resuscitation in emergency department (ED).MethodsWe recruited adult patients planned to receive a resuscitation fluid bolus. Patients were monitored using a thoracic electrical bioimpedance (TEB) cardiac output monitor (Niccomo, Medis, Germany). A 3-min PLR was carried out before and after fluid infusion. Stroke volume changes (ΔSV) were calculated and a positive response was defined as ≥ 15% increase.ResultsWe recruited 39 patients, of which 37 were included into the analysis. The median age was 63 (50–77) years and 19 patients were females. 17 patients (46%) were fluid responders compared to 11 (30%) with positive response to PLR1. ΔSV with PLR1 and fluid bolus showed moderate correlation (r = 0.47, 95% confidence interval, CI 0.17–0.69) and 62% concordance rate. For the prediction of the response to a fluid bolus the PLR test had a sensitivity of 41% (95% CI 22–64) and specificity of 80% (95% CI 58–92) with an area under the curve of 0.59 (95% CI 0.41–0.78). None of the standard parameters showed a better predictive ability compared to PLR.ConclusionUsing TEB, ΔSV with PLR showed a moderate correlation with fluid bolus, with a limited accuracy to predict fluid responsiveness. The PLR test was a better predictor of fluid responsiveness than the parameters commonly used in emergency care (such as heart rate and blood pressure). These data suggest the potential for a clinical trial in sepsis comparing TEB monitored, PLR directed fluid management with standard care.

Noninvasive cardiac output monitor to quantify hydration status in ischemic stroke patients: A feasibility study

BackgroundIndividuals who are dehydrated, volume contracted or both at the time of hospitalization for acute ischemic stroke have worse clinical outcomes than do individuals with optimal volume status. Currently, there is no gold standard method for measuring hydration status, except indirect markers of a volume contracted state (VCS) including elevated blood urea nitrogen (BUN)/creatinine ratio. We sought to test the feasibility and acceptability of a non-invasive cardiac output monitor (NICOM) for the measurement of hydration status in a group of hospitalized ischemic stroke patients, and explore the relationship with a common indirect laboratory-based measure of VCS. MethodsWe performed a prospective observational feasibility study of hospitalized acute ischemic stroke patients. We collected hemodynamic parameters using the NICOM device before and after fluid auto-bolus via passive leg raise and BUN/creatinine ratio. Successful acquisition of relevant hemodynamic data was the primary objective of this study. We explored agreement between the NICOM results and BUN/creatinine ratio using Cohen's kappa statistic. ResultsThirty patients hospitalized with acute ischemic stroke were enrolled. We found that 29/30 patients tolerated assessment with NICOM. Hemodynamic data were collected in all 30 patients. Data capture took an average of 10 min(SD ± 112 s). Agreement between NICOM and BUN/creatinine ratio was 70%; (expected agreement 51%; kappa 0.38). Agreement was stronger in the cohort without history of diabetes (81% agreement, kappa 0.61). ConclusionsNICOM assessment was feasible in hospitalized stroke patients. The identification of an objective, real-time measure of hydration status would be clinically useful, and could allow precise, goal-directed care.

Non-invasive continuous cardiac output monitoring in infants with hypoxic ischaemic encephalopathy

ObjectiveTo describe early, continuous, non-invasive measures of cardiac output (CO) and evolution over time in infants with hypoxic-ischaemic encephalopathy (HIE).Study designProspective observational study of 44 infants with HIE (23 mild, 17 moderate, 4 severe) and 17 term controls. Infants with HIE had non-invasive CO monitoring (NICOM) continuously in the neonatal unit. Term controls had NICOM recorded at 6 and 24 h. A mixed-modelling approach was used to assess change in CO over time by group.ResultsInfants with moderate HIE have significantly lower CO than the mild group at all timepoints (10.7 mls/kg/min lower, 95% CI:1.0,20.4, p = 0.03) which increases over time, driven by a gradual increase in stroke volume (SV). CO increased further during rewarming predominantly due to an increase in HR.ConclusionTH has a significant impact on HR but SV appears largely unaffected. NICOM may provide a non-invasive, continuous, low-cost alternative to monitoring CO in infants with HIE however further research is warranted.

Non-invasive cardiac output monitoring with electrical velocimetry after cardiac surgery in infants.

Low cardiac output following cardiac surgery is a major determinant of outcome that may be improved by early detection, yet there are no widely accepted methods for its measurement in young children. We evaluated the feasibility of the routine use of electrical velocimetry, a non-invasive technique providing continuous measurement of cardiac output, in infants in the early postoperative period. With ethical approval and parental consent, infants undergoing cardiac surgery were recruited. The ICON electrical velocimetry monitor was attached on admission to the intensive care unit (ICU) and remained for up to 24h. A total of 15 infants were recruited, median age 3months (interquartile range (IQR) 0.5-7.5) and weight 4.8kg (IQR 3.9-7.1), undergoing various operations. Cardiac index had a weak correlation with arterial lactate (r=-0.24, p=0.02) and no correlation with blood pressure, central venous pressure or arteriovenous oxygen difference. Data were recorded for a median of 19h (range 5-24), with lead detachment or movement artefact the most common causes of data loss. There was marked minute-to-minute variability, with 25% of consecutive measurements having >5% variability. Cardiac index measured by electrical velocimetry in infants in the early postoperative period is impaired by frequent data loss and marked intrapatient variability. Our feasibility study suggests that it is unsuitable for use as a routine monitoring tool in the setting of postsurgical ICU care.

Haemodynamic effects of a 10-min treatment with a high inspired oxygen concentration in the emergency department: a prospective observational study

Previous studies show that prolonged exposure to a high inspired oxygen concentration (FiO2) is associated with unfavourable haemodynamic effects. Until now, it is unknown if similar effects also occur after...

Hypoxia during maintenance hemodialysis-the critical role of pH.

The impact and management of subclinical hypoxia during hemodialysis is a significant medical challenge. As key determinants of O2 availability and delivery, proposed mechanisms contributing to hypoxia include ischemia, alkalemia and pulmonary leukocyte sequestration. However, no study has comprehensively investigated and compared these interrelated mechanisms throughout a typical hemodialysis treatment week. This study aimed to comprehensively assess the physiological mechanisms that contribute to hypoxia during hemodialysis. In 76 patients, we measured arterial blood gases and pH at four time-points during hemodialysis (start, 15min, 60min, end) over the course of a standard treatment week. For the mid-week hemodialysis session, we additionally measured central hemodynamics (non-invasive cardiac output monitoring) and white blood cell count. Linear regression modelling identified changes in pH, but not central hemodynamics or white blood cell count, to be predictive of changes in PaO2 throughout hemodialysis (e.g. at 60min, β standardized coefficient pH=0.45, model R2=0.25, P<.001). Alkalemia, hypokalemia, decreased calcium and increased hemoglobin-O2 affinity (leftward shift in the oxyhemoglobin dissociation curve) were evident at the end of hemodialysis. pH and hemoglobin-O2 affinity at the start of hemodialysis increased incrementally over the course of a standard treatment week. These data highlight the important role of pH in regulating O2 availability and delivery during hemodialysis. Findings support routine pH monitoring and personalized dialysate bicarbonate prescription to mitigate the significant risk of alkalemia and subclinical hypoxia.

Hyperphosphatemia and its relationship with blood pressure, vasoconstriction, and endothelial cell dysfunction in hypertensive hemodialysis patients

BackgroundHyperphosphatemia occurs frequently in end-stage renal disease patients on hemodialysis and is associated with increased mortality. Hyperphosphatemia contributes to vascular calcification in these patients, but there is emerging evidence that it is also associated with endothelial cell dysfunction.MethodsWe conducted a cross-sectional study in hypertensive hemodialysis patients. We obtained pre-hemodialysis measurements of total peripheral resistance index (TPRI, non-invasive cardiac output monitor) and plasma levels of endothelin-1 (ET-1) and asymmetric dimethylarginine (ADMA). We ascertained the routine peridialytic blood pressure (BP) measurements from that treatment and the most recent pre-hemodialysis serum phosphate levels. We used generalized linear regression analyses to determine independent associations between serum phosphate with BP, TPRI, ET-1, and ADMA while controlling for demographic variables, parathyroid hormone (PTH), and interdialytic weight gain.ResultsThere were 54 patients analyzed. Mean pre-HD supine and seated systolic and diastolic BP were 164 (27), 158 (21), 91.5 (17), and 86.1 (16) mmHg. Mean serum phosphate was 5.89 (1.8) mg/dL. There were significant correlations between phosphate with all pre-hemodialysis BP measurements (r = 0.3, p = .04; r = 0.4, p = .002; r = 0.5, p < .0001; and r = 0.5, p = .0003.) The correlations with phosphate and TPRI, ET-1, and ADMA were 0.3 (p = .01), 0.4 (p = .007), and 0.3 (p = .04). In our final linear regression analyses controlling for baseline characteristics, PTH, and interdialytic weight gain, independent associations between phosphate with pre-hemodialysis diastolic BP, TPRI, and ET-1 were retained (β = 4.33, p = .0002; log transformed β = 0.05, p = .005; reciprocal transformed β = -0.03, p = .047).ConclusionsSerum phosphate concentration is independently associated with higher pre-HD BP, vasoconstriction, and markers of endothelial cell dysfunction. These findings demonstrate an additional negative impact of hyperphosphatemia on cardiovascular health beyond vascular calcification.Trial registrationThe study was part of a registered clinical trial, NCT01862497 (May 24, 2013).

Renal and Vascular Effects of Combined SGLT2 and Angiotensin-Converting Enzyme Inhibition.

Background:The cardiorenal effects of sodium-glucose cotransporter 2 inhibition (empagliflozin 25 mg QD) combined with angiotensin-converting enzyme inhibition (ramipril 10 mg QD) were assessed in this mechanistic study in patients with type 1 diabetes with potential renal hyperfiltration.Methods:Thirty patients (out of 31 randomized) completed this double-blind, placebo-controlled, crossover trial. Recruitment was stopped early because of an unexpectedly low proportion of patients with hyperfiltration. Measurements were obtained after each of the 6 treatment phases over 19 weeks: (1) baseline without treatment, (2) 4-week run-in with ramipril treatment alone, (3) 4-week combined empagliflozin-ramipril treatment, (4) a 4-week washout, (5) 4-week combined placebo-ramipril treatment, and (6) 1-week follow-up. The primary end point was glomerular filtration rate (GFR) after combination treatment with empagliflozin-ramipril compared with placebo-ramipril. GFR was corrected for ramipril treatment alone before randomization. At the end of study phase, the following outcomes were measured under clamped euglycemia (4 to 6 mmol/L): inulin (GFR) and para-aminohippurate (effective renal plasma flow) clearances, tubular sodium handling, ambulatory blood pressure, arterial stiffness, heart rate variability, noninvasive cardiac output monitoring, plasma and urine biochemistry, markers of the renin-angiotensin-aldosterone system, and oxidative stress.Results:Combination treatment with empagliflozin-ramipril resulted in an 8 mL/min/1.73 m2 lower GFR compared with placebo-ramipril treatment (P=0.0061) without significant changes to effective renal plasma flow. GFR decrease was accompanied by a 21.3 mL/min lower absolute proximal fluid reabsorption rate (P=0.0092), a 3.1 mmol/min lower absolute proximal sodium reabsorption rate (P=0.0056), and a 194 ng/mmol creatinine lower urinary 8-isoprostane level (P=0.0084) relative to placebo-ramipril combination treatment. Sodium-glucose cotransporter 2 inhibitor/angiotensin-converting enzyme inhibitor combination treatment resulted in additive blood pressure–lowering effects (clinic systolic blood pressure lower by 4 mm Hg [P=0.0112]; diastolic blood pressure lower by 3 mm Hg [P=0.0032]) in conjunction with a 94.5 dynes × sex/cm5 lower total peripheral resistance (P=0.0368). There were no significant changes observed to ambulatory blood pressure, arterial stiffness, heart rate variability, or cardiac output with the addition of empagliflozin.Conclusions:Adding sodium-glucose cotransporter 2 inhibitor treatment to angiotensin-converting enzyme inhibitor resulted in an expected GFR dip, suppression of oxidative stress markers, additive declines in blood pressure and total peripheral resistance. These changes are consistent with a protective physiologic profile characterized by the lowering of intraglomerular pressure and related cardiorenal risk when adding a sodium-glucose cotransporter 2 inhibitor to conservative therapy.Registration:URL: https://www.clinicaltrials.gov; Unique identifier: NCT02632747.

Effect of Preanesthetic Fluid Loading on Postinduction Hypotension and Advanced Cardiac Parameters in Patients with Chronic Compressive Cervical Myelopathy: A Randomized Controlled Trial.

Purpose Hypotension during the early intraoperative phase is common and can lead to adverse perioperative outcomes. Fluid preloading is one of the methods to limit its occurrence. Patients with chronic compressive cervical myelopathy may have autonomic dysfunction, which can aggravate hemodynamic alterations during anesthesia. This study compared the occurrence of postinduction hypotension and changes in cardiac dynamic indices in patients with and without crystalloid preloading undergoing decompressive cervical spine surgery. Methods This randomized controlled trial was conducted over 15 months after obtaining patient consent, approval of the institute ethics committee, and trial registration. We compared preanesthetic fluid loading with Ringer's lactate (20 mL/kg over 30 minutes) with no preloading (2 mL/kg/h maintenance) in 60 consecutive patients undergoing cervical spine surgery. The ANSiscope was used to determine baseline cardiac autonomic function. Noninvasive cardiac output monitor was used to assess changes in heart rate, mean arterial pressure, cardiac index (CI), stroke volume variation (SVV), and total peripheral resistance index during study intervention, anesthetic induction, tracheal intubation, and change in position from supine to prone. Results The incidences of postinduction hypotension were 26.7% (8/30) and 86.7% (26/30) and the median doses of mephentermine used were 0 and 6 mg, respectively, in patients with and without fluid preloading (both p < 0.001). Preloading resulted in improvement in CI, reduction in SVV, and lesser vasopressor use. Conclusion Preloading reduced the occurrence of postinduction hypotension and vasopressor use, improved CI, and reduced SVV during the early intraoperative period. Registration number of Clinical Trial The trial was registered with Clinical Trial Registry of India (CTRI/2018/07/014970 on 19/07/2018).

Non-invasive cardiac output monitoring before and after baby extubation – A feasibility study (NICOMBabe study)

BackgroundMechanical ventilation induces changes in intrapleural, intrathoracic and intra-abdominal pressure. These changes have various implications on cardiac output (CO). AimsThe aim of this study was to determine the feasibility of measuring changes in CO after elective extubation in neonates using the principle of transthoracic bioreactance (TBR). Study designThis was a prospective observational cohort study in a level III neonatal centre. CO, stroke volume (SV) and heart rate were measured continuously for 2 h before and 2 h after elective extubation by TBR. SubjectsNeonates undergoing elective extubation were eligible for enrolment. Outcome measuresThe primary outcome of the study was change in CO post elective extubation. ResultsTen neonates were enrolled, seven (70 %) had a statistically significant decrease in CO after extubation, three (30 %) infants had a statistically significant increase in CO after extubation. Changes in CO were primarily driven by changes in SV and the pattern of change was related to patent ductus arteriosus (PDA) status prior to extubation. ConclusionExtubation significantly influences CO in neonatal patients and the pattern of change appears to be related to PDA status.

20-OR: The Renal and Vascular Effects of Combined SGLT2 and Angiotensin Converting Enzyme Inhibition

The goal of this mechanistic trial was to determine the kidney and cardiovascular effects of combined treatment with an SGLT2i (empagliflozin 25mg QD) and an ACEi (ramipril 10mg QD) for 4 weeks in patients at risk of renal hyperfiltration. In this randomized, double-blind, placebo-controlled, cross-over trial, measurements were obtained following each of the 4 treatment phases: 1) no treatment, 2) 4-week ramipril treatment alone, 3) 4-week empagliflozin-ramipril combination treatment, and 4) 4-week placebo-ramipril combination treatment. The primary endpoint was GFR after empagliflozin-ramipril treatment compared to placebo-ramipril. At the end of each study phase the following measurements were performed under clamped euglycemia (4-6 mmol/L) : inulin (GFR) and paraaminohippurate (effective renal plasma flow, ERPF) clearances, tubular sodium handling, ambulatory blood pressure, arterial stiffness, heart rate variability, non-invasive cardiac output monitoring, plasma and urine biochemistry. Empagliflozin-ramipril treatment resulted in an 8ml/min/1.73m2 lower GFR (p=0.0061) , lower absolute proximal fluid reabsorption rate (p=0.0092) , lower absolute proximal sodium reabsorption rate (p=0.0056) , and lower urinary 8-isoprostane (p=0.0084) relative to placebo-ramipril treatment. Empagliflozin-ramipril treatment resulted in additive blood pressure lowering effects (SBP p=0.0112; DBP p=0.0032) and a lower total peripheral resistance (p=0.0368) . There were no other significant changes observed with the addition of empagliflozin. SGLT2i-ACEi combination treatment resulted in an expected GFR “dip”, suppression of oxidative stress markers, and additive declines in blood pressure and total peripheral resistance in this mechanistic study. These changes are consistent with a protective physiological profile characterized by the lowering of intraglomerular pressure and related cardiorenal risk when adding an SGLT2i to conservative therapy. Disclosure Y. Lytvyn: None. K. Kimura: Employee; 3Boehringer Ingelheim Canada Ltd./Ltée. N. Peter: Employee; Boehringer Ingelheim Pharma GmbH &amp; Co.KG. V.S. Lai: Advisory Panel; Baxter. J. Tse: None. L. Cham: None. B.A. Perkins: Advisory Panel; Abbott Diabetes, Insulet Corporation, Sanofi. Board Member; Novo Nordisk. Research Support; BMO Bank of Montreal, Novo Nordisk. Other Relationship; Abbott Diabetes, Insulet Corporation, Medtronic, Novo Nordisk. N. Soleymanlou: Employee; Boehringer Ingelheim Pharmaceuticals Inc., Boehringer Ingelheim Pharmaceuticals Inc. D. Cherney: Research Support; Boehringer Ingelheim-Lilly, Merck, Janssen, Sanofi, AstraZeneca and Novo-Nordisk. Other Relationship; AbbVie Inc., AstraZeneca, Bayer AG, Boehringer Ingelheim International GmbH, Janssen Research &amp; Development, LLC, Lilly, Maze, BMS, CSL-Behring, Merck, Otsuka, Novartis and Novo-Nordisk, Mitsubishi Tanabe Pharma Corporation, Sanofi. Funding Boehringer Ingelheim and CIHR, Diabetes Canada and the Heart and Stroke Richard Lewar Centre of Excellence and the Heart and Stroke Foundation of Canada

Non-invasive Cardiac Output Monitoring and Assessment of Fluid Responsiveness in Children With Shock in the Emergency Department.

IntroductionThe assessment of fluid responsiveness is important in the management of shock but conventional methods of assessing fluid responsiveness are often inaccurate. Our study aims to evaluate changes in objective hemodynamic parameters as measured using electrical cardiometry (ICON® monitor) following the fluid bolus in children presenting with shock and to evaluate whether any specific hemodynamic parameter can best predict fluid responsiveness among children with shock.Materials and MethodsWe conducted a prospective observational study in children presenting with shock to our emergency department between June 2020 and March 2021. We collected the parameters such as heart rate (HR), respiratory rate (RR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and hemodynamic data such as cardiac output CO), cardiac index (CI), index of contractility (ICON), stroke volume (SV), stroke index (SI), corrected flow time (FTC), systolic time ratio (STR), variation of index of contractility (VIC), stroke volume variation (SVV), systemic vascular resistance (SVR), and thoracic fluid content (TFC) using the ICON monitor before and after fluid bolus (FB). We assessed percent change (Δ) and used paired-sample Student’s t-test to compare pre- and post-hemodynamic data and Mann–Whitney U-test to compare fluid responders and non-responders. P-Values < 0.05 were considered statistically significant.ResultsWe recorded 42 fluid interventions in 40 patients during our study period. The median IQR age was 10.56 (4.8, 14.8) years with male/female ratio (1.2:1). There was a significant decrease in ΔRR [−1.61 (−14.8, 0); p = 0.012], ΔDBP [−5.5 (−14.4, 8); p = 0.027], ΔMAP [−2.2 (−11, 2); p = 0.018], ΔSVR [−5.8 (−20, 5.2); p = 0.025], and ΔSTR [−8.39 (−21, 3); p = 0.001] and significant increase in ΔTFC [6.2 (3.5, 11.4); p = 0.01] following FB. We defined fluid responders by an increase in SV by ≥10% after a single FB of 20 ml/kg crystalloid. Receiver operating curve analysis revealed that among all the parameters, 15% change in ICON had an excellent AUC (0.85) for the fluid responsiveness.ConclusionOur study showed significant changes in objective hemodynamic parameters, such as SVR, STR, and TFC following FB in children presenting with shock. A 15% change in ICON had an excellent predictive performance for the fluid responsiveness among our cohort of pediatric shock.