Ultrasound Cardiac Output Monitor Research Articles

The “Preeclampsia and Hypertension Target Treatment” study: a multicenter prospective study to evaluate the effectiveness of the antihypertensive therapy based on maternal hemodynamic findings

Despite major advances in the pharmacological treatment of hypertension in the non-pregnant population, treatments for hypertension in pregnancy have remained largely unchanged over the years. There is recent evidence that a more adequate control of maternal blood pressure is achieved when the first given antihypertensive drug is able to correct the underlying hemodynamic disorder of the mother beside normalizing the blood pressure values. to compare the blood pressure control in women receiving an appropriate or inappropriate antihypertensive therapy in accordance with the baseline hemodynamic findings STUDY DESIGN: prospective multicenter study including a population of women with de novo diagnosis of HDP. A noninvasive assessment of the following maternal parameters was done upon the hospital admission by means of USCOM (Ultrasound Cardiac Output Monitor) before any antihypertensive therapy was given: Cardiac Output (CO), Heart Rate (HR), Systemic Vascular Resistance (SVR), Stroke Volume (SV). The clinician who prescribed the antihypertensive therapy was blinded to the hemodynamic evaluation and based on his preferences or on the local protocols used as 1st line a vasodilator (nifedipine or alpha methyldopa) or a beta-blocker (labetalol). The 1st line pharmacological treatment was retrospectively considered hemodynamically appropriate in either of the following circumstances: 1) Women with a hypodynamic profile (defined as low cardiac output [CO≤5L/min] and/or high systemic vascular resistance [SVR≥1300 dynes*s*cm]) who were administered oral nifedipine or alpha methyldopa. 2) Women with a hyperdynamic profile (defined as normal or high cardiac output [CO >5 L/min] and/or low systemic vascular resistances [SVR<1300 dynes*s*cm-]) who were administered oral labetalol. The primary outcome of the study was to compare the occurrence of severe hypertension between the women who were found to be treated with a hemodynamically appropriate or inappropriate therapy. A total of 152 women with HDP were included in the final analysis. Of these the majority displayed a hypodynamic profile (114 or 75.0%) and received a hemodynamically appropriate treatment (116 or 76.3%). The occurrence of severe hypertension prior to delivery was significantly lower in the group receiving an appropriate therapy compared with those inappropriately treated (6.0% vs. 19.4%; p= 0.02). Moreover, the number of women who achieved target values of BP within 48-72h from the treatment start was higher in the group who received an appropriate treatment (70.7% vs. 50.0%; p=0.02). In pregnant individuals with de novo HDP, a lower occurrence of severe hypertension is observed when the first line antihypertensive agent is tailored to the correct maternal hemodynamic profile.

Factors influencing ultrasound cardiac output monitor waveform quality in patients admitted to the emergency intensive care unit

ObjectiveThe ultrasonic cardiac output monitor (USCOM), an instrument that monitors the evolution of a patient's hemodynamic status and determines the type of shock, has become an important tool for assessing cardiac pathology and predicting changes in disease, but there are some variations in the instrumental findings for different physical conditions of patients. This article examines whether there are differences in the quality of USCOM waveforms measured in different types of critically ill patients based on clinical characteristics and test parameters. MethodsBaseline data, diagnoses, echocardiograms, ventilation patterns, and USCOM results were retrospectively collected from patients in the emergency intensive care unit. Waveform quality was quantified using the Fremantle score to determine the extent to which age, body mass index (BMI), chronic obstructive pulmonary disease (COPD), respiratory failure, cardiac enlargement, valvular heart disease, and ventilation pattern influenced USCOM waveform quality. ResultsAge, body mass index, chronic obstructive pulmonary disease, respiratory failure, right and left heart enlargement, aortic valve disease (excluding aortic stenosis), and ventilation mode did not have a significant effect on USCOM waveform quality in critically ill patients (P > 0.05). ConclusionsVarious physical conditions of critically ill patients may have limited effect on the quality of the USCOM waveform, potentially rendering USCOM suitable for early assessment of hemodynamic status during ICU admission.

Longitudinal maternal hemodynamic evaluation in uncomplicated twin pregnancies according to chorionicity: physiological cardiovascular dysfunction in monochorionic twin pregnancy.

Maternal cardiac function plays a crucial role in placental function and development. The maternal hemodynamic changes in twin pregnancy are more pronounced than those in singleton pregnancy, presumably due to a greater plasma volume expansion. In view of the correlation between maternal cardiac and placental function, it is plausible that chorionicity could influence maternal cardiac function. The aim of this study was to compare the longitudinal maternal hemodynamic changes between uncomplicated dichorionic (DC) and monochorionic (MC) twin pregnancies and in comparison to singleton pregnancies. Included in the study were 40 MC diamniotic and 35 DC diamniotic uncomplicated twin pregnancies. These were compared with a group of 294 healthy singleton pregnancies from a previous cross-sectional study. All participants underwent a hemodynamic evaluation using an Ultrasound Cardiac Output Monitor (USCOM®), at three different stages in pregnancy (11-15 weeks, 20-24 weeks and 29-33 weeks). The following parameters were recorded: mean arterial pressure (MAP), stroke volume (SV), stroke volume index (SVI), heart rate, cardiac output (CO), cardiac index (CI), systemic vascular resistance (SVR), systemic vascular resistance index (SVRI), stroke volume variation, Smith-Madigan inotropy index (INO) and potential-to-kinetic-energy ratio (PKR). In the first trimester, DC and MC twin pregnancies showed lower MAP, SVR and PKR and higher CO and SV in comparison to singleton pregnancy. In the second trimester, maternal CO (8.33 vs 7.30 L/min, P = 0.03) and CI (4.52 vs 4.00 L/min/m2 , P = 0.02) were significantly higher in MC compared with DC twin pregnancy. In the third trimester, compared with in singleton pregnancy, women with MC twin pregnancy showed significantly higher PKR (24.06 vs 20.13, P = 0.03) and SVRI (1837.20 vs 1698.48 dynes × s/cm5 /m2 , P = 0.03), and significantly lower SV (78.80 vs 88.80 mL, P = 0.01), SVI (42.79 vs50.31 mL/m2 , P < 0.01) and INO (1.70 vs 1.87 W/m2 , P = 0.03); these differences were not observed between DC twin and singleton pregnancies. Maternal cardiovascular function undergoes significant change during uncomplicated twin pregnancy and chorionicity influences maternal hemodynamics. In both MC and DC twin pregnancy, hemodynamic changes are detectable as early as the first trimester, showing higher maternal CO and lower SVR compared with singleton pregnancy. In DC twin pregnancy, the maternal hemodynamics remain stable during the rest of pregnancy. In contrast, in MC twin pregnancy, the rise in maternal CO continues in the second trimester in order to sustain the greater placental growth. There is a subsequent crossover, with a reduction in cardiovascular performance during the third trimester. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Reference ranges for third-trimester maternal cardiovascular function parameters measured in normotensive pregnant women using a non-invasive cardiac output monitor: A study based on data from the prospective PEACH cohort study.

We defined reference ranges for maternal cardiac output, systemic vascular resistance, and stroke volume measured in the third trimester of pregnancy using the Ultrasound Cardiac Output Monitor 1A. Based on data from the prospective PEACH (PreEclampsia, Angiogenesis, Cardiac dysfunction and Hypertension) cohort study. Rigshospitalet and Hvidovre Hospital, Denmark. Normotensive pregnant women aged 18-45 years with singleton pregnancies, enrolled in the PEACH study in 2016-2018. We modelled cardiac output, systemic vascular resistance and stroke volume as a function of gestational age using multilevel linear models with fractional polynomials. Unconditional and conditional reference ranges for cardiovascular parameters measured in gestational weeks 28-40. Our study cohort included 405 healthy pregnant women who contributed 1210 cardiovascular function measurements for analysis. Maximum cardiac output and stroke volume values were measured in gestational weeks 30-32 and decreased over the third trimester, whereas systemic vascular resistance increased during the same period. We created reference ranges for eight combinations of maternal height, age and parity. We also created a simple calculator to allow for implementation of the reference ranges in clinical practice. Our reference ranges allow the use of a bedside ultrasound device to non-invasively assess cardiac function in pregnancy and identify women at risk of complications. The unconditional ranges allow clinicians to evaluate isolated measurements and identify women needing follow-up. The conditional ranges incorporate information from previous measurements and improve monitoring over time.

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&amp;nbsp;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.

Comparison of the effectiveness of USCOM and echocardiography in assessing cardiac output on pediatric patients with shock

BackgroundShock is a circulatory failure, and its clinical manifestations result in decreased cardiac output. Hemodynamic monitoring is important in shock patients to determine further management. Demand for noninvasive examination methods, such as ultrasound cardiac output monitoring (USCOM) and echocardiography, is increasing because of their practicality and lower risks. ObjectivesThe aim of this study is to compare cardiac output determined using USCOM and echocardiography in pediatric patients with shock. MethodsThis prospective observational study used a cross-sectional data collection approach. It collected data on 48 pediatric shock patients in the Pediatric Intensive Care Unit at Kandou General Hospital (Manado, Indonesia) between March and June 2022. The instruments used were USCOM and echocardiography. The regression analysis results are presented as odds ratios (ORs) with 95 % confidence intervals and p < 0.05. ResultsThe mean cardiac output of pediatric patients with shock was 2.50 (standard deviation [SD] = 2.28) with USCOM and 2.45 (SD = 0.77) with echocardiography. Echocardiographic and USCOM cardiac output values were significantly correlated, with a coefficient of determination (R2) of 0.832 (83.2 %), indicating a near-perfect linear correlation. ConclusionThis study's results show that USCOM is as effective as echocardiography in assessing cardiac output in children with shock.

UltraSound cardiac output monitoring in volemic status evaluation in emergency department

UltraSound cardiac output monitoring in volemic status evaluation in emergency department

The impact of pre-pregnant obesity on the maternal hemodynamics in early pregnancy

Maternal obesity is associated with a substantial risk of complications during pregnancy. Furthermore, it also impacts maternal cardiovascular adaptation, leading to cardiovascular disease later in life. This study aims to investigate the hemodynamic impact of obesity in the first trimester using USCOM® (Ultrasound Cardiac Output Monitor), a non-invasive and quantitative method. A prospective observational study of women with singleton pregnancy enrolled in prenatal care at a University of Miami clinic between January 2022 and July 2022. Pregnant women with a history of preexisting severe cardiorespiratory disease or congenital heart defect affecting cardiac function and taking Aspirin were excluded. Comprehensive cardiovascular parameters via USCOM® were obtained. Patients were divided into three subgroups: normal weight, overweight, and obesity according to pre-pregnancy BMI. Data were analyzed by one-way ANOVA with post hoc Bonferroni test for continuous parametric data, Kruskal-Wallis test for non-parametric data, and Pearson chi-square test for categorical data. P < .05 was considered statistically significant. Doppler waveforms for analysis were achieved for 48 women among 57 participants. Gestational age at inclusion, maternal age, ethnicity, race, blood pressure, history of preeclampsia, and preexisting chronic hypertension was not significantly different between groups. Maternal cardiovascular changes were identified in group 3. Compared to women with normal weight, obese women had significantly elevated Ejection Time Percentage (ET%) and Flow Time Corrected (FTc), and significantly reduced Stroke Volume Index(SVI), Cardiac Index(CI), and Inotropy Index(II). However, Stroke Volume (SV), Cardiac Output (CO), systemic vascular resistance (SVR), and Peak Velocity (PV) are not significantly different between groups. Our study shows that maternal hemodynamics is significantly altered in obese pregnant women from the first trimester and is characterized by high preload, low afterload, and reduced cardiac function.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Vascular Reactivity Index and PELOD-2 as a mortality predictor in paediatric septic shock: a single-centre retrospective study

BackgroundThe mortality rate for children with septic shock is stil quite high in low-income and middle-income countries (31.7%). One of the most widely used scoring systems to assess mortality in...

Maternal hemodynamics in first trimester: feasibility study in our cohort of patient

Introduction and aims of the study: Hemodynamic measurement seems to play an important role in the understanding, prediction and management of a growing range of pregnancy complications. Nowadays a number of non-invasive cardiac output monitors are available on the market. In this study we use ultrasound cardiac output monitor 1A (USCOM-1A). The main aim of this study was to determine intraobserver and interobserver variability of hemodynamic measurement in our cohort of patient in the first trimester of pregnancy using USCOM-1A.

Ultrasound cardiac output monitoring in mechanically ventilated children.

To non-invasively identify the hemodynamic changes in critically ill children during the first 48 h following initiation of mechanical ventilation by the ultrasound cardiac output monitor (USCOM) method and compare the data in children with pulmonary and non-pulmonary pathology. This was a prospective observational study to evaluate the influence of mechanical ventilation on hemodynamic changes and to describe hemodynamic profiles of mechanically ventilated children. A total of 56 children with respiratory failure were included in the present study. Ventilated patients are divided into two groups. Group A (n=36) includes patients with pulmonary pathology. Group B (n=20) consists of patients with extra pulmonary etiology of respiratory failure. Hemodynamic parameters (cardiac index and systemic vascular resistance index) were evaluated using ultrasound cardiac output monitoring (USCOM 1A) immediately following initiation of mechanical ventilation and again at 6, 12, and 48 h. Pharmacological circulatory support (inotropes, vasopressors, levosimendan and phosphodiesterase III inhibitors) was individually and continuously modified based on real-time hemodynamic parameters and optimal fluid balance. No significant differences in hemodynamic profiles were found between Group A and Group B. The protective strategy of mechanical ventilation was not associated with significant differences in hemodynamic profiles between children ventilated for pulmonary and non-pulmonary pathologies. Hemodynamically unstable children ventilated for pulmonary pathology with the protective strategy of mechanical ventilation had a greater requirement for inotropic and combined inotropic and vasoactive circulatory support than children ventilated for non-pulmonary causes of respiratory failure.

Inferior Vena Cava/Abdominal Aorta Ratio as a Guide for Fluid Resuscitation.

Introduction:The fluid therapy is crucial in the treatment of critically ill children. Inadequate or excessive fluid resuscitation leads to increased mortality and morbidity, thus necessitating an accurate parameter for predicting fluid responsiveness when conducting fluid resuscitation. The inferior vena cava/abdominal aorta (IVC/Ao) ratio is suggested as a good guide for fluid resuscitation. However, the cutoff value for predicting fluid responsiveness in children has not been established. Is IVC/Ao ratio can be used to predict fluid responsiveness?Methods:The objective was to determine the accuracy and a cutoff value of IVC/Ao in predicting fluid responsiveness. A prospective cross-sectional study was conducted in the emergency room and the pediatric intensive care unit of the tertiary hospital from March to August 2017. We consecutively enrolled all critically ill children aged 1 month to 18 years' old who were hemodynamically unstable (shock). Measurements of IVC/Ao with ultrasound and stroke volume with ultrasound cardiac output monitor were obtained before and after fluid challenge.Results:Of 167 subjects enrolled in this study, only 58 subjects were included, most of whom were male (58.6%) and ranging in age from 1 to 11 months (32.8%). The mean IVC/Ao ratio before the fluid challenge in the fluid responsive group was 0.70 ± 0.053. The best cutoff of the IVC/Ao ratio is 0.675 with area under the curve 70.8% (95% confidence interval of 54.6%–87%), 75.7% sensitivity, and 61.9% specificity for predicting significant fluid responsiveness.Conclusion:The measurement of IVC/Ao is an accurate, sensitive, and specific parameter to predict fluid responsiveness. The best cut-off for the IVC/Ao ratio is 0.675.

Maternal haemodynamic function differs in pre‐eclampsia when it is associated with a small‐for‐gestational‐age newborn: a prospective cohort study

To describe maternal haemodynamic differences in gestational hypertension with small-for-gestational-age babies (HDP+SGA), gestational hypertension with appropriate-for-gestational-age babies (HDP-only) and control pregnancies. Prospective cohort study. Tertiary Hospital, UK. Women with gestational hypertension and healthy pregnant women. Maternal haemodynamic indices were measured using a non-invasive Ultrasound Cardiac Output Monitor (USCOM-1A® ) and corrected for gestational age and maternal characteristics using device-specific reference ranges. Maternal cardiac output, stroke volume, systemic vascular resistance. We included 114 HDP+SGA, 202 HDP-only and 401 control pregnancies at 26-41weeks of gestation. There was no significant difference in the mean arterial blood pressure (110 versus 107mmHg, P=0.445) between the two HDP groups at presentation. Pregnancies complicated by HDP+SGA had significantly lower median heart rate (76 versus 85bpm versus 83bpm), lower cardiac output (0.85 versus 0.98 versus 0.97MoM) and higher systemic vascular resistance (1.4 versus 1.0 versus 1.2MoM) compared with control and HDP-only pregnancies, respectively (all P<0.05). Women with HDP+SGA present with more severe haemodynamic dysfunction than HDP-only. Even HDP-only pregnancies exhibit impaired haemodynamic indices compared with normal pregnancies, supporting a role of the maternal cardiovascular system in gestational hypertension irrespective of fetal size. Central haemodynamic changes may play a role in the pathogenesis of pre-eclampsia and should be considered alongside placental aetiology. Hypertensive disorders of pregnancy are associated with worse maternal haemodynamic function when associated with small-for-gestational-age birth.

[Ultrasound cardiac output monitor and thermodilution for cardiac function monitoring in critical patients: a Meta-analysis].

To assess the differences between ultrasound cardiac output monitor (USCOM) and thermodilution (TD) systematically in cardiac function monitoring of critically ill patients. The Chinese and English literatures about the clinical trials which using USCOM and TD to monitor cardiac function published in CNKI, Wanfang database, China biomedical literature database, VIP database, China Clinical Trial Registration Center, PubMed, Embase and Cochrane Library were searched by computer from the establishment to December 2018. Some indicators, like cardiac output (CO), cardiac index (CI), stroke volume (SV) and other parameters were used to evaluate cardiac function. Literature search, quality evaluation and data extraction were conducted independently by two authors. The tailored Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) was used for literature quality evaluation. EndNote X6 was used for literature screening and management. RevMan 5.3 was used for Meta-analysis. Funnel chart analysis was used for publication bias. A total of 26 studies involving 772 patients were included. Among them, there were 5 literatures found that the agreements of cardiac function between the USCOM and TD methods were poor. Meta-analysis showed that there was no significant difference between the two methods in CO and CI monitoring [CO: mean difference (MD) = -0.06, 95% confidence interval (95%CI) was -0.17 to 0.05, P = 0.31; CI: MD = -0.04, 95%CI was -0.13 to 0.05, P = 0.38]. Subgroup analysis of different TD methods [pulmonary artery catheter (PAC), pulse indicator continuous cardiac output (PiCCO)] and different windows of USCOM ultrasonic probe [aorta (AA), pulmonary artery (PA)] in CO monitoring was not shown significant difference yet (PAC: MD = -0.07, 95%CI was -0.18 to 0.04, P = 0.23; PiCCO: MD = 0.09, 95%CI was -0.31 to 0.50, P = 0.65; AA windows: MD = -0.14, 95%CI was -0.31 to 0.02, P = 0.09; PA windows: MD = -0.00, 95%CI was -0.15 to 0.14, P = 0.95; AA/PA windows: MD = 0.23, 95%CI was -0.40 to 0.86, P = 0.47). However, the difference in SV was statistically significant between the USCOM and TD method (MD = 1.48, 95%CI was 0.04 to 2.92, P = 0.04). Funnel chart showed that the literature distribution of CO and CI monitoring were basically symmetrical, indicating that the bias of literature publication is small. USCOM has good consistency with TD method in monitoring the cardiac function parameters of CO and CI, and different windows of ultrasonic probe of USCOM have no significant influence on the monitoring results, but there is significant difference in the consistency of the two methods in SV monitoring.

Observational study in healthy volunteers to define interobserver reliability of ultrasound haemodynamic monitoring techniques performed by trainee doctors.

Bedside ultrasound is increasingly being used to guide fluid management in shocked patients. Little data exist on the inter-rater reliability of techniques used, especially when performed by nonexpert trainee doctors. The primary aim of this study is to measure the inter-rater reliability of five ultrasound techniques commonly used to guide fluid management: inferior vena cava collapsibility index (IVCCI), transthoracic echocardiography (TTE)-derived stroke volumes, ultrasound cardiac output monitor (USCOM) derived stroke volume and carotid artery blood flow and corrected flow time measurements. Two Royal College of Emergency Medicine level one ultrasound-certified emergency medicine trainees performed paired ultrasound measurements on 31 healthy nonpatient volunteers. Inter-rater reliability was assessed through three indices: interclass correlation coefficient (ICC), limits of agreements (LOAs) derived from Band-Altman plots and the proportion of paired scans with absolute differences of less that 15% (defined as agreement). TTE-derived measurements performed the best overall, with an LOA of 22%, an ICC of 0.55 and an agreement of 80%. USCOM also performed well, with an LOA of 33%, an ICC of 0.68 and an agreement of 58%. IVCCI and carotid artery-derived measurements performed poorly across all indices. TTE-derived measurements showed the highest level of inter-rater reliability and can thus be expected to provide reliable measures over time with different sonographer clinicians. USCOM interobserver reliability was also adequate for clinical use. However, on the basis of inter-reliability measures, IVCCI and carotid artery measurements were found to be inadequate for clinical use.

Progress in noninvasive assessment of fluid responsiveness

Fluid infusion is one of the most common therapeutic measures in clinical practice. With the development of medical technology, the assessment of fluid responsiveness before fluid infusion has become simpler and less invasive. The assessment of fluid responsiveness is based on three aspects: cardiopulmonary interaction, volume-loading test and endogenous volume-loading test. This article reviews the progress in the assessment of fluid responsiveness with the application of ultrasound and noninvasive continuous cardiac output monitoring, and the prospect of future improvement. Key words: Noninvasive; Ultrasound; Continuous cardiac output monitoring; Fluid responsiveness

189. Non-invasive study of haemodynamic parameters in normotensive versus hypertensive pregnancies

Background/Objectives Major physiological cardiovascular system adaptations during pregnancy include decreased systemic vascular resistance (SVR) and increased cardiac output (CO). In hypertensive disorders of pregnancy, especially preeclampsia, these usual cardiovascular adaptations maybe deficient. This study aims to evaluate differences in cardiac function and haemodynamic parameters using point-of-care, non-invasive testing, in women with normotensive and hypertensive (chronic hypertension, CH, gestational hypertension, GH preeclampsia, PE) pregnancies. Methods Normotensive (NT, n = 70) and hypertensive (HT, n = 65; 23 CH, 22 GH, 20 PE) pregnant women aged 18–45 with a singleton pregnancy studied cross-sectionally from 20 weeks’ gestation in this ongoing prospective study. Haemodynamic parameters were obtained non-invasively via the Ultrasound Cardiac Output Monitor (USCOM) and liquid crystal sphygmomanometer. Women are followed prospectively and pregnancy outcomes, including preeclampsia development, ascertained. Results There was no statistically significant difference in average stroke volume (73 mL/NT, 69 mL/CH, 70 mL/GH, 73 mL/PE; p = 0.838), cardiac output (5.9/5.7/5.5 and 5.7L respectively; p = 0.802) and cardiac output index between groups (3.2/2.8/2.7/2.9L/min/m2; p = 0.16) between groups. Pre-eclamptic pregnancies had significantly higher SVR (1851 ± 1111 versus 1215 ± 396 dyne/se/cm−5; p ⩽ 0.001) and systematic vascular resistance index (3653 ± 2189 versus 2274 ± 912dyne/s/cm−5/m−2; p ⩽ 0.001) than NT pregnancies. As expected, HT participants had significantly higher mean arterial pressure, systolic (110 ± 12,129 ± 11, 129 ± 10, 138 ± 12; p ⩽ 0.001) and diastolic blood pressure (70 ± 9, 79 ± 9, 83 ± 8, 87 ± 12 mmHg respectively; p ⩽ 0.001) than NT. Conclusions In this pilot study of non-invasive (USCOM) haemodynamic measurements, significant differences in systemic vascular resistance, but not overall cardiac output, were seen between normotensive and hypertensive pregnancies. A larger sample size is needed for further investigation, including determining whether USCOM may be useful in predicting which pregnancies will progress from gestational hypertension and/or chronic hypertension, to preeclampsia.

Application value of bedside noninvasive hemodynamic monitoring in the diagnosis and treatment of neonatal septic shock

Objective To evaluate the application value of bedside noninvasive hemodynamic monitoring in the diagnosis and treatment of neonatal septic shock. Methods The purchase time and use of Ultrasound Cardiac Output Monitor (USCOM) to monitor hemodynamic status were taken as the grouping condition, and the infants admitted to Department of Neonatology in Shanghai Children′s Hospital from March 2014 to December 2016 were divided into 3 groups, 16 of USCOM′s pre-purchased septic shock infants were taken as non-USCOM monitoring group, 20 patients with septic shock received USCOM monitoring as USCOM monitoring group, the other 20 non-septic shock neonates were assigned as a control group, whose primary diseases were premature, neonatal jaundice or neonatal pneumonia.Systolic volume (SV), cardiac output (CO), heart rate (HR), cardiac index (CI) and systemic vascular resistance index (SVRI) in USCOM monitoring group and control group were recorded.The doses of dopamine, dobutamine, epinephrine or norepinephrine and the time of vasoactive drug administration were compared between the USCOM monitoring group and non-USCOM monitoring group.The data of 3 groups were analyzed statistically. Results Compared with the control group, the hemodynamic parameters of the USCOM monitoring group before treatment such as CO [(0.68±0.44) L/min vs.(0.44±0.17) L/min, t=3.306, P=0.004], CI [(4.40±1.88) L/(min·m2) vs.(3.00±0.40)L/(min·m2), t=3.328, P=0.004], SV [(3.90±2.39) cm3vs.(3.08±0.31) cm3, t=2.227, P=0.038] and HR [(166.09±26.20) times/min vs.(145.35±16.16) times/min, t=2.750, P=0.013] were increased, while the SVRI showed an obvious decline [(795.88±450.19) d·s/(cm5·m2) vs.(1 160.61±49.59) d·s/(cm5·m2), t=-2.898, P=0.009], and the differences were statistically significant.While in the USCOM monitoring group after treatment, the CO [(0.56±0.28) L/min vs.(0.68±0.44) L/min, t=2.456, P=0.024] and CI [(3.65±1.10) L/(min·m2) vs.(4.40±1.88) L/(min·m2), t=2.614, P=0.017] were decreased significantly compared with those in USCOM monitoring group before treatment.Compared with non-USCOM monitoring group, the doses of dopamine [(45.72±28.80) mg/kg vs.(85.83±69.33) mg/kg, t=2.352, P=0.005], dobutamine [(12.81±26.18) mg/kg vs.(85.83±69.33) mg/kg, t=4.351, P=0.002], epinephrine [(0.11±0.33) mg/kg vs.(0.90±1.75) mg/kg, t=1.986, P=0.014], and the time of vasoactive drug use [(68.10±34.37) h vs.(167.75±117.14) h, t=3.626, P=0.001] were decreased significantly in USCOM monitoring group.The doses of norepinephrine [(1.91±3.79) mg/kg vs.(0.47±0.90)mg/kg, t=-1.481, P=0.046]were increased significantly in USCOM monitoring group. Conclusion The noninvasive hemodynamic monitoring plays an important role in the diagnosis and treatment of septic shock in neonates by clarifying the hemodynamic status of shock and guiding the rational use of vasoactive drugs so as to improve the successful rescue rate. Key words: Bedside noninvasive hemodynamics monitoring; Ultrasound cardiac output monitor; Infant, newborn; Septic shock

Evolution of Acute Kidney Injury and Its Association With Systemic Hemodynamics in Children With Fluid-Refractory Septic Shock.

There are no studies in pediatrics evaluating the progression of acute kidney injury in septic shock. We investigated the evolution of sepsis-associated acute kidney injury and its association with systemic hemodynamics in children with fluid-refractory septic shock. Prospective cohort study. PICU of a tertiary care hospital. All patients with fluid-refractory septic shock (n = 61) between September 2010 and February 2014. Hemodynamic variables using noninvasive ultrasound cardiac output monitor were measured at admission and 6 hourly thereafter till 48 hours. We used the Kidney Disease: Improving Global Outcomes criteria to define and stage acute kidney injury. Associations between various hemodynamic variables and development of acute kidney injury were evaluated. Severe acute kidney injury was defined as stage 2 or 3 acute kidney injury and was compared with no acute kidney injury or stage 1 acute kidney injury. Severe acute kidney injury developed in 29.5% (n = 18) of the 61 children with fluid-refractory septic shock, whereas 43 patients (70.49%) had either no or stage 1 acute kidney injury. Most patients who developed acute kidney injury did so within the first 48 hours of PICU admission. Severe acute kidney injury conferred a three-fold increased risk of death by day 28 (hazard ratio, 3.23; 95% CI, 1.52-6.67; p = 0.002), longer ICU stay, and increased duration of mechanical ventilation. Central venous pressure at presentation was higher in severe acute kidney injury by 5 cm H2O. Highest lactate in the first 24 hours of PICU admission, low diastolic blood pressure, low systemic vascular resistance index at admission were associated with severe acute kidney injury. This model reliably predicted stage 2/3 acute kidney injury by day 3 with area under the curve equals to 94%; 95% CI, 88.3-99.99. None of the other hemodynamic variables showed any association with severe acute kidney injury. Manifestations of sepsis-associated acute kidney injury often occur early after PICU admission and is associated with increased morbidity and mortality. There is a need to develop a predictive model in septic shock which could facilitate early detection of acute kidney injury.

Haemodynamic responses of wearing low-pressure sports compression tights during an orthostatic challenge in healthy individuals

ObjectivesWhile previous studies have demonstrated an ergogenic effect of sport compression garments in exercise performance and recovery, the possible underlying mechanisms remain unclear. Claims for improved venous return from wearing sport compression garments with a low compression pressure remain unproven. The aim of this study was to determine the pressure profile exerted by low-pressure sports compression tights, and to investigate using a non-invasive Doppler ultrasound cardiac output monitor (USCOM), whether the compression applied will influence haemodynamic responses during an orthostatic challenge. DesignA randomized-crossover design. MethodsThirty-three healthy participants (18 male and 15 female) underwent two trials, each consisting of lying supine and 70° head-up tilt wearing either a low-pressure sports compression tights (CT) or track pants (CON). Stroke volume (SV) and cardiac output (CO) were measured non-invasively using USCOM; heart rate (HR) and non-invasive blood pressure were measured, and systemic vascular resistance (SVR) was derived. ResultsThe SV and CO was lower at 70° head-up tilt than in supine but wearing CT attenuated the decline in SV (25.9±11.6cm3 CT vs. 35.9±11.4cm3 CON, p<0.001), CO (1.1±0.7 Lmin−1 CT vs. 1.4±0.6 Lmin−1 CON, p<0.05), HR (8.8±8.4 beatmin−1 CT vs. 15.9±9.7 beatmin−1 CON, p<0.001) and SVR (740±504dscm−5 CT vs. 961±560dscm−5 CON, p<0.005). The mean arterial pressure (3.3±4.1mmHg CT vs. 3.6±4.5mm Hg CON, p>0.05) was similar in both trials. ConclusionsHealthy individuals wearing low-pressure sports compression tights experienced less severe haemodynamic disturbance such as decreases in CO, SV, HR and SVR during an orthostatic challenge.