Maternal vascular indices and hemodynamic parameters at 36 weeks' gestation in gestational and pre-existing diabetes mellitus.

OBJECTIVE: To compare maternal vascular indices and hemodynamic parameters at 35-37 weeks' gestation in pregnancies complicated by gestational diabetes mellitus (GDM), those with pre-existing diabetes mellitus (DM) and those without GDM or pre-existing DM. METHODS: This was a prospective observational study in women with a singleton pregnancy attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. The visit included recording of maternal demographic characteristics and medical history, and measurement of vascular indices and hemodynamic parameters using a non-invasive operator-independent device. These included carotid-to-femoral pulse-wave velocity, augmentation index, cardiac output, stroke volume, central systolic and diastolic blood pressure, total peripheral resistance and heart rate. The values in the GDM and pre-existing DM groups were compared to those in the unaffected group. RESULTS: We examined 6746 women, of whom 396 were excluded because they had chronic hypertension or developed pre-eclampsia or gestational hypertension. The study population of 6350 pregnancies contained 99 (1.6%) with pre-existing Type-I or Type-II DM and 617 (9.7%) that developed GDM, including 261 (42.3%) that were treated with diet alone, 239 (38.7%) treated with metformin alone and 117 (19.0%) treated with insulin with or without metformin. Among women with GDM and those with pre-existing DM, compared to those without GDM or pre-existing DM, there was a higher median cardiac output and heart rate, central systolic and diastolic blood pressure and pulse-wave velocity, but there was no significant difference in stroke volume and total peripheral resistance. There were no significant differences within the GDM group according to treatment type, except for higher heart rate in women treated with metformin alone compared to the group treated with diet alone. CONCLUSION: Women with GDM and those with pre-existing DM have evidence of early vascular disease in the third trimester, and this may contribute to their increased long-term cardiovascular risk. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Small changes in the transducer position cause a systematic change in cardiac output readings: implications for clinical practice.

To systematically evaluate the effect of small changes in transducer position on key hemodynamic variables including CO generated by 4th generation FloTrac software. After cardiac surgery, cardiac output, mean arterial pressure, systemic vascular resistance, and stroke volume variation were measured with 4 generation Flotrac software. The transducer position was randomly placed at the midaxillary plane, 4 cm higher than the midaxillary plane or 4 cm lower than the midaxillary plane. Averages of three measurements were used. Data was available from 20 patients. Cardiac output increased from 4.59 L/min (± 0.92) to 4.78 L/min (± 0.99) with the transducer position at the midaxillary plane to 4 cm higher than the midaxillary plane, and cardiac output decreased to 4.43 L/min (± 0.90) with the transducer 4 cm lower than midaxillary plane (P < 0.001). On the relative scale, CO increased 4.1% (95% CI 3.1-5.0) when comparing the higher transducer level with the midaxillary plane position, and CO decreased 3.4% (95% CI 2.4-4.4) when comparing the midaxillary plane position with the lower transducer level, correspondiong to changes in CO of ≈ 1% per 1 cm change in transducer position. Mean arterial pressure and systemic vascular resistance both changed significantly with transducer position (both P < 0.001), whereas no statistically or clinically significant effect was seen on stroke volume variation (P = 0.98). A four-centimeter change in vertical transducer position induced clinically significant changes in cardiac output measurements by 4th generation FloTrac software. Definitions of optimal cardiac output in goal-directed therapy algorithms require meticulous transducer adjustment and can only be used in the reference patient position.

Third-Trimester Cardiovascular Function and Risk of Hypertensive Disorders of Pregnancy.

BACKGROUND: Whether cardiovascular dysfunction is associated with preeclampsia in women without fetal growth restriction (FGR) is unclear. Our objective was to investigate associations between third-trimester cardiac output (CO) and systemic vascular resistance and risk of hypertensive disorders of pregnancy in women with and without FGR. METHODS AND RESULTS: A case-cohort study in 906 pregnant women in Denmark with repeated third-trimester cardiac function assessments was performed using the Ultrasound Cardiac Output Monitor 1A. Using Cox regression, we compared rates of hypertensive disorders of pregnancy in women with low, normal, and high CO and normal and high systemic vascular resistance, by FGR status and gestational age, and evaluated associations between a third-trimester drop in CO or increase in systemic vascular resistance and preeclampsia risk in women without FGR. The analysis included 249 women with preeclampsia (42 with FGR) and 119 women with gestational hypertension. Low CO was strongly associated with preeclampsia at <37 weeks (women with FGR: hazard ratio [HR], 5.25 [95% CI, 1.26-21.9]; women without FGR: HR, 2.19 [95% CI, 1.07-4.48]). Our results also suggested an association between low CO and preeclampsia at ≥37 weeks among women without FGR (HR, 1.31 [95% CI, 0.84-2.03]), and between a third-trimester drop in CO >75th percentile and preeclampsia in women without FGR (odds ratio, 1.91 [95% CI, 0.84-4.36]). High systemic vascular resistance was strongly associated with increased rates of all forms of hypertensive disorders of pregnancy. CONCLUSIONS: Low CO is associated with preeclampsia risk in women with and without FGR, particularly before 37 weeks. Repeated measurements of third-trimester cardiovascular function might identify women without FGR for monitoring for preeclampsia, but this result needs to be confirmed in other studies.

Predictors of low cardiac output syndrome after combined mitral and tricuspid valve surgery.

Introduction: Low cardiac output syndrome (LCOS) is a common complication in cardiac surgery, and we evaluated the incidence of its early occurrence after mitral and tricuspid combined cardiac surgery and its associated risk factors. Material and method: Retrospective, single institution study. We included 88 consecutive adult patients with severe mitral insufficiency scheduled for elective mitral and tricuspid valve replacement surgery between January 2015 and November 2018. The primary endpoint was the occurrence of LCOS, defined as the need for inotropic support or circulatory assistance after surgery. The secondary endpoint was mortality at 30 days. Results: LCOS occurred in 26 patients (29.5%) of the studied patients and its associated risk factors that appeared in the multivariate analysis were chronic kidney failure [adjusted odds ratio (OR) 3.1; 95% confidence interval (CI) 1.0-9.9, p = 0.05], pre-operative left ventricular heart failure (OR 5.3; 95% CI 1.3-10.9, p = 0.002), pre-operative right ventricular heart failure (OR 3.6; 95% CI 1.1-11.5, p = 0.02), and mitral valve replacement (OR 3.9; 95% CI 1.2-12.6, p = 0.03). LCOS affected the survival of patients (HR = 5.5; 95% CI 1.1-27.7 p = 0.04). Conclusion: LCOS is a frequent complication after mitral and tricuspid combined surgery and is associated with poor prognosis.

Transpulmonary cardiac output with room temperature saline is accurate and tracks directional changes in anesthetized dogs.

OBJECTIVE: To assess the performance of transpulmonary thermodilution (TPTD) using room-temperature saline (CORT) and waveform-derived continuous CO (CCO) compared with TPTD using iced saline (COICED) as the indicator for measurements of CO in isoflurane-anesthetized dogs. METHODS: 8 Beagles aged 1 to 2 years (7.4 to 11.2 kg) were enrolled in this experimental study from March 21 to 31, 2023. Dogs were anesthetized with 0.01 mg/kg acepromazine, 5 to 6 mg/kg propofol, and isoflurane and were mechanically ventilated. Dogs were instrumented with a central venous catheter and a femoral arterial catheter equipped with a thermistor. The COICED, CORT, and pulse wave-derived CCO values were obtained at baseline, during infusions of phenylephrine and norepinephrine, and during blood withdrawal and replacement. Data were analyzed with a mixed effect model, Bland-Altman plots, and concordance. Percent error was calculated. P < .05 was used for significance. RESULTS: Data were collected from 8 dogs. Significant effects of time and the interaction of time and method were found. Bland-Altman plots showed negligible bias with limits of agreement between -0.35 and 0.25 L/min for CORT versus COICED and -1.23 and 1.15 L/min for CCO versus COICED. Percent errors were 17.7% and 66.6%, respectively. In the 4-quadrant plots, the concordance rate was 95% and 68% for measurements obtained with CORT and for CCO, respectively. CONCLUSIONS: Transpulmonary thermodilution using room temperature saline was accurate and able to track changes in CO. Continuous CO had a large percent error and low tracking ability. CLINICAL RELEVANCE: Transpulmonary thermodilution using room temperature saline is reliable for monitoring CO and obviates the need for iced preparations in clinical scenarios.

Correlation between corrected carotid flow time and left ventricular outflow tract velocity-time integral using a novel technique.

BACKGROUND: Transthoracic echocardiography (TTE) is widely used for assessing patients in the intensive care unit, with cardiac output measurement being crucial for hemodynamic monitoring. This is achieved by measuring the velocity-time integral (VTI) of the left ventricular outflow tract (LVOT), which serves as a surrogate of stroke volume. However, conducting TTE in the critical care setting presents several challenges. Our primary objective was to investigate the relationship between carotid corrected flow time (cCFT) and LVOT VTI. Additionally, we aimed to determine the threshold cCFT value that reliably predicts a normal LVOT VTI. MATERIALS AND METHODS: This proof-of-concept study involves a post-hoc analysis from a diagnostic accuracy investigation conducted in a medical-surgical intensive care unit. We included patients admitted to the ICU from December 2021 to January 2022. We used a phased array transducer to measure the cCFT at the left supraclavicular fossa and the LVOT VTI in an apical 5-chamber view. RESULTS: We included 22 patients. The Spearman coefficient between LVOT VTI and cCFT was 0.82 (p < 0.0001). The area under the ROC curve for cCFT to predict LVOT VTI equal to or greater than 17 cm was 0.871 (95% CI 0.660-0.974). A cCFT exceeding 283 ms predicted LVOT VTI equal to or greater than 17 cm with a sensitivity of 93.3% (95% CI 68.1% to 99.8%) and specificity of 85.7% (95% CI 42.1% to 99.6%). CONCLUSION: The cCFT, measured using a novel technique with a phased array transducer, shows a strong correlation with LVOT VTI. Additionally, cCFT predicts a normal LVOT VTI with good sensitivity and specificity in critically ill patients. Larger studies are warranted to validate these findings.

A Case Report of Wet Beriberi Due to Excessive White Rice Consumption in an Elderly Male Patient: A Potentially Forgotten and Underrecognized Disease.

Thiamine deficiency can cause various clinical manifestations. Wet beriberi, a phenotype of thiamine deficiency, is often underdiagnosed in clinical practice due to the nonspecificity of symptoms. An 83-year-old man presented to a primary care clinic with a two-month history of progressing edema in the scrotum and lower extremities. The patient reported a weight gain of 10 kg and was treated with diuretics. However, his condition did not improve even after four weeks. The patient was referred to our hospital for further cardiac evaluation. Transthoracic echocardiographic findings were suggestive of a high cardiac output (CO) state, and the thiamine level was decreased. Further medical interview revealed that the patient had a habit of eating two or three large bowls of white rice with a few side dishes for breakfast and dinner. The hemodynamic evaluation revealed high CO and low systemic vascular resistance. The patient's weight decreased from 56.6 to 52.4 kg in the first 2 days after thiamine administration. Six days later, his weight further decreased to 50.8 kg and edema disappeared completely. Clinicians should be aware that excessive consumption of white rice with few side dishes may lead to thiamine deficiency. This case highlights the importance of considering wet beriberi as a cause of excessive edema with high CO state.

Neutrophil-to-lymphocyte ratio as a predictor of low cardiac output syndrome after open heart surgery in children with congenital heart disease.

Neutrophil-to-lymphocyte ratio (NLR) as a predictor in determining low cardiac output syndrome (LCOS) has not been widely reported. The aim of this study was to explore the role of pre-surgery, 0-, 4-, and 8-hour post-surgery NLR as predictors of LCOS incidence after open heart surgery in children with congenital heart disease (CHD). This study used a prognostic test with a prospective cohort design and was conducted from December 2020 until June 2021 at the cardiac intensive care unit (CICU) of Dr. Cipto Mangunkusumo Hospital, Jakarta, Indonesia. The subject consisted of children aged one month to 18 years who underwent open heart surgery using a cardiopulmonary bypass (CPB) machine. A receiver operating characteristic curve was applied to identify the predictive performance of NLR for poor outcomes (LCOS incidence). Out of 90 patients included in the study, 25 (27.8%) of them developed LCOS between 3 to 53 hours post-surgery. All NLR values (pre-surgery and 0-, 4-, and 8-hours post-surgery) were associated with the incidence of LCOS. Pre-surgery NLR (cut-off value ≥0.88) had a fair predictive value (area under curve (AUC) 70; 95%CI: 57-83) for predicting LCOS incidence with sensitivity and specificity of 64% and 64.62%, respectively. NLR 0-hour post-surgery (cut-off value ≥4.73) had a good predictive value (AUC 81; 95%CI: 69-94) for predicting LCOS incidence, with 80% sensitivity and 80% specificity. NLR 4- and 8-hours post-surgery had very good predictive values (AUC 97%; 95%CI: 92-100 and 98; 95%CI: 94-100, respectively), with cut-off values ≥6.19 and ≥6.78, had the same 92% sensitivity and the same 96% sensitivity. The presence of LCOS was associated with mortality (odds ratio of 5.11 with 95%CI: 3.09-8.46). This study highlights that pre-surgery, 0-, 4-, and 8-hours post-surgery NLR can be predictors of LCOS after open heart surgery in children with CHD.

Correlation, agreement and concordance of cardiac output estimated by transthoracic ultrasound and transesophageal Doppler with pulmonary artery thermodilution in anesthetized cats.

OBJECTIVE: To characterize the correlation, agreement and concordance of cardiac output (CO) measured with transthoracic ultrasound and the correlation and concordance of aortic blood flow (ABF) minute distance (MD) measured by transesophageal Doppler with CO measured by pulmonary artery thermodilution (PATD) in cats. STUDY DESIGN: Experimental study. ANIMALS: A group of six healthy male neutered cats, aged 2-8 years and weighing 5.3 ± 0.3 kg. METHODS: Cats were anesthetized with isoflurane in oxygen. CO was measured by PATD (COPATD) and transthoracic echocardiography (COECHO). ABF MD was measured using an esophageal Doppler flow probe aligned with descending ABF. All measurements were made under three conditions: dexmedetomidine (20 µg kg-1) intravenously; atipamezole (200 µg kg-1) intramuscularly and atropine (20 µg kg-1) intravenously as needed to achieve a minimum heart rate of 140 beats minute-1; and dopamine (20 µg kg-1 minute-1) intravenously in that order. Correlation between COPATD and COECHO, and COPATD and Doppler MD was evaluated using repeated measures correlation. Agreement between COPATD and COECHO was evaluated using Bland-Altman method. Differences between consecutive pairs of CO measurements were calculated for concordance analysis. RESULTS: Correlation between COPATD and COECHO and between COPATD and MD was significant (p < 0.001), with correlation coefficients greater than 0.92. A bias of > 27% and upper limits of agreement of 66% were found between COPATD and COECHO. Concordance rate with COPATD was 76-80% for COECHO and 72% for MD. CONCLUSIONS AND CLINICAL RELEVANCE: Echocardiographic methods for the measurement of CO showed poor agreement and concordance with PATD. MD showed poor concordance with PATD. As such, these methods cannot be used as an alternative to PATD nor can they appropriately track changes in CO in anesthetized cats.

Passive leg raising test versus rapid fluid challenge in critically ill medical patients.

BACKGROUND: The passive leg raising (PLR) test is a simple test to detect preload responsiveness. However, variable fluid doses and infusion times were used in studies evaluating the effect of PLR. Studies showed that the effect of fluid challenge on hemodynamics dissipates in 10 min. This prospective study aimed to compare PLR and a rapid fluid challenge (RFC) with a 300-ml bolus infused within 5 min in adult patients with a hemodynamic compromise. MATERIALS AND METHODS: Critically ill medical patients with signs of systemic hypoperfusion were included if volume expansion was considered. Hemodynamic status was assessed with continuous measurements of cardiac output (CO), when possible, and mean arterial pressure (MAP) at baseline, during PLR, and after RFC. RESULTS: A total of 124 patients with a median age of 65.0 years were included. Their acute physiology and chronic health evaluation (APACHE) II score was 19.7 ± 6.0, with a sequential organ failure assessment (SOFA) score of 9.0 ± 4.4. Sepsis was diagnosed in 73.3%, and 79.8% of the patients were already receiving a norepinephrine infusion. Invasive MAP monitoring was established in all patients, while continuous CO recording was possible in 42 patients (33.9%). Based on CO changes, compared with those with RFC, the false positive and false negative rates with PLR were 21.7 and 36.8%, respectively, with positive and negative predictive values of 70.6 and 72.0%, respectively. Based on MAP changes, compared with those with RFC, the false positive and false negative rates with PLR compared to RFC were 38.2% and 43.3%, respectively, with positive and negative predictive values of 64.4 and 54.0%, respectively. CONCLUSION: This study demonstrated a moderate agreement between PLR and RFC in hemodynamically compromised medical patients, which should be considered when testing preload responsiveness.

Novel techniques for quantifying oxygen pulse curve characteristics during cardiopulmonary exercise testing in tetralogy of fallot.

Background: Cardiopulmonary exercise testing (CPET) is used in evaluation of repaired tetralogy of Fallot (rTOF), particularly for pulmonary valve replacement need. Oxygen pulse (O2P) is the CPET surrogate for stroke volume and peripheral oxygen extraction. Objectives: This study assessed O2P curve properties against non-invasive cardiac output monitoring (NICOM) and clinical testing. Methods: This cross-sectional study included 44 rTOF patients and 10 controls. Three new evaluations for O2P curve analysis during CPET were developed. Best fit early and late regression slopes of the O2P curve were used to calculate: 1) the early to late ratio, or "O2 pulse response ratio" (O2PRR); 2) the portion of exercise until slope inflection, or "flattening fraction" (FF); 3) the area under the O2P response curve, or "O2P curve area". Results: rTOF patients (median age 35.2 (27.6-39.4); 61% female) had a lower VO2 max (23.4 vs 45.6 ml/kg/min; p < 0.001) and O2P max (11.5 vs 19.1 ml/beat; p < 0.001) compared to controls. Those with a FF occurring <50% through exercise had a lower peak cardiac index and stroke volume, but not VO2 max, compared to those >50%. FF and O2P curve area significantly correlated with peak cardiac index, stroke volume, left and right ventricular ejection fraction, and right ventricular systolic pressure. Conclusion: CPET remains an integral part in the evaluation of rTOF. We introduce three non-invasive methods to assess exercise hemodynamics using the O2P curve data. These evaluations demonstrated significant correlations with stroke volume, cardiac output, and right ventricular pressure.

Estimation of Systolic and Diastolic Left Ventricular Blood Flow From Derivatives of Transesophageal Echocardiographic 3D Volume Curves in Cardiac Surgery Patients: A Proof-of-Concept Study.

OBJECTIVES: To examine whether estimates of peak global systolic (S') and diastolic (E') left ventricular (LV) flow rates based on 3D echocardiographic volumes are feasible and match physiology. METHODS: In this retrospective feasibility study, we included patients undergoing major cardiac surgery. S' and E' were derived from 190 patients by taking the first derivative of the volume-time relationship of 3D ecg-gated transesophageal echocardiography (TEE) images. To examine the quality of images upon which the estimates of flow were based we correlated intraoperative 3D TEE and preoperative 2D transthoracic echocardiography (TTE) volumes. As a proof-of-concept, we then correlated S' flow with stroke volume and S' and E' were compared by valve pathology. RESULTS: In each of the 190 images, S' and E' were derived. There was good correlation between 1) the ejection fraction (EF) of 3D LV images obtained intraoperatively by TEE and preoperatively by TTE (Pearson's r = 0.65) and also 2) S' and stroke volume (Pearson's r = 0.73). Patients with aortic or mitral regurgitation showed higher S' than patients without valve pathologies (-315 mL/s [95% CI -388 mL/s to -264 mL/s]P = 0.001, -319 mL/s [95% CI -397 mL/s to -246 mL/s]P = 0.001 vs -242 mL/s [95% CI -300 mL/s to -196 mL/s]). These patients also showed higher E' than patients without valve pathologies (302 mL/s [95% CI 237 mL/s to 384 mL/s]P = 0.006, 341 mL/s [95%CI 227 mL/s to 442 mL/s]P = 0.001 vs 240 mL/s [95%CI 185 mL/s to 315 mL/s]). Patients with aortic stenosis showed no difference in S' or E' (-263 mL/s [95%CI -300 mL/s to -212 mL/s]P = 0.793, 255 mL/s [95%CI 188 mL/s to 344 mL/s]P = 0.400). CONCLUSIONS: Estimates of global peak systolic and diastolic LV flow based on 3D TEE are feasible, promising, and match valve pathologies.

A larval zebrafish model of cardiac physiological recovery following cardiac arrest and myocardial hypoxic damage.

Contemporary cardiac injury models in zebrafish larvae include cryoinjury, laser ablation, pharmacological treatment and cardiac dysfunction mutations. Although effective in damaging cardiomyocytes, these models lack the important element of myocardial hypoxia, which induces critical molecular cascades within cardiac muscle. We have developed a novel, tractable, high throughput in vivo model of hypoxia-induced cardiac damage that can subsequently be used in screening cardioactive drugs and testing recovery therapies. Our potentially more realistic model for studying cardiac arrest and recovery involves larval zebrafish (Danio rerio) acutely exposed to severe hypoxia (PO2=5-7 mmHg). Such exposure induces loss of mobility quickly followed by cardiac arrest occurring within 120 min in 5 days post fertilization (dpf) and within 40 min at 10 dpf. Approximately 90% of 5 dpf larvae survive acute hypoxic exposure, but survival fell to 30% by 10 dpf. Upon return to air-saturated water, only a subset of larvae resumed heartbeat, occurring within 4 min (5 dpf) and 6-8 min (8-10 dpf). Heart rate, stroke volume and cardiac output in control larvae before hypoxic exposure were 188±5 bpm, 0.20±0.001 nL and 35.5±2.2 nL/min (n=35), respectively. After briefly falling to zero upon severe hypoxic exposure, heart rate returned to control values by 24 h of recovery. However, reflecting the severe cardiac damage induced by the hypoxic episode, stroke volume and cardiac output remained depressed by ∼50% from control values at 24 h of recovery, and full restoration of cardiac function ultimately required 72 h post-cardiac arrest. Immunohistological staining showed co-localization of Troponin C (identifying cardiomyocytes) and Capase-3 (identifying cellular apoptosis). As an alternative to models employing mechanical or pharmacological damage to the developing myocardium, the highly reproducible cardiac effects of acute hypoxia-induced cardiac arrest in the larval zebrafish represent an alternative, potentially more realistic model that mimics the cellular and molecular consequences of an infarction for studying cardiac tissue hypoxia injury and recovery of function.

Critical Care Ultrasound in Shock: A Comprehensive Review of Ultrasound Protocol for Hemodynamic Assessment in the Intensive Care Unit.

Shock is a life-threatening condition that requires prompt recognition and treatment to prevent organ failure. In the intensive care unit, shock is a common presentation, and its management is challenging. Critical care ultrasound has emerged as a reliable and reproducible tool in diagnosing and classifying shock. This comprehensive review proposes an ultrasound-based protocol for the hemodynamic assessment of shock to guide its management in the ICU. The protocol classifies shock as either low or high cardiac index and differentiates obstructive, hypovolemic, cardiogenic, and distributive etiologies. In distributive shock, the protocol proposes a hemodynamic-based approach that considers the presence of dynamic obstruction, fluid responsiveness, fluid tolerance, and ventriculo-arterial coupling. The protocol gives value to quantitative measures based on critical care ultrasound to guide hemodynamic management. Using critical care ultrasound for a comprehensive hemodynamic assessment can help clinicians diagnose the etiology of shock and define the appropriate treatment while monitoring the response. The protocol's use in the ICU can facilitate prompt recognition, diagnosis, and management of shock, ultimately improving patient outcomes.

Bioreactance noninvasive cardiac output monitoring in euvolemic adult horses subjected with 7.2% saline and 6% hydroxyethyl starch (130/0.4) solution infusions.

OBJECTIVE: To compare the ability of bioreactance noninvasive cardiac output (BR-NICO) with thermodilution cardiac output (TDCO) for the measurement of cardiac output (CO) in healthy adult horses receiving 2 different IV volume replacement solutions. DESIGN: Prospective randomized crossover study from September to November 2021. SETTING: University teaching hospital. ANIMALS: Six university-owned adult horses. INTERVENTIONS: Horses were randomly assigned to receive 7.2% hypertonic saline solution (HSS) or 6% hydroxyethyl starch (130/0.4) solution (HETA). BR-NICO and TDCO were measured simultaneously at baseline, 10, 20, 30, 40, 50, 60, 90, and 120 minutes before fluid administration and again at the same times after starting a bolus infusion of IV volume replacers. All solutions were administered within 10 minutes. MEASUREMENTS AND MAIN RESULTS: BR-NICO and TDCO were strongly correlated (Pearson r2 = 0.93; P < 0.01). Regression analysis showed the relationship between TDCO and BR-NICO was BR-NICO = 0.48 × TDCO + 0.6. For the corrected BR-NICO values, the Bland-Altman agreement mean bias and lower/upper limits of agreement were -0.62 and -5.3 to 3.9 L/min, respectively. Lin's concordance (95% confidence interval) between methods was 0.894 (0.825-1.097). Compared with baseline, HSS increased the CO at 10 and 20 minutes (TDCO and BR-NICO). Compared with baseline, HETA decreased the CO at 10 and 20 minutes (TDCO and BR-NICO) and increased the CO at 90 (TDCO only) and 120 minutes (TDCO and BR-NICO). CONCLUSIONS: BR-NICO strongly agreed with TDCO in the measurement of CO in healthy unsedated adult horses. HSS administration significantly increased CO in the first 30 minutes, while HETA initially decreased CO at 10 minutes but increased CO to above baseline values by 90 minutes.

Agreement of cardiac index measurements between ultrasonic cardiac output monitor and transthoracic echocardiography in neonates.

OBJECTIVES: To evaluate the agreement of cardiac index (CI) calculated by Ultrasonic sonic cardiac output monitor (USCOM) and transthoracic thoracic echocardiography (TTE) in order to know if we can recommend USCOM in our pediatric intensive care unit (PICU). DESIGN: Prospective observational evaluative study carried out over a period of 3 months Setting: PICU at children's hospital in Tunis Participants: All newborns without tracheostomy or a known congenital heart disease, admitted to the PICU during the study period were enrolled. INTERVENTIONS: Paired and consecutive measurements of CI were obtained in all patients with both technologies. All measurements by TTE and USCOM were performed by two distinct operators. It is the average of three successive measures of the CI, in the same patient, with each technology, which was considered. Agreement of CI between the 2 techniques was assessed by Bland-Altman analysis and percentage error. MEASUREMENTS AND MAIN RESULTS: Forty-two infants were analyzed with the mean (standard deviation) gestation 36 weeks ( 5 days), age 1 days (1.09) , and weight 2.9 kg (0.87). Respiratory failure was the main cause of admission 75%. At the time of the study, 33 (75.%) patients were ventilated artificially. Bias (mean difference) of the CI between the two methods was 1.2 l/min/m2 and precision (± 2 SD of differences) was 1.08 l/min/m2. The MPE of CI measurement for USCOM vs TTE was 54.9%. CONCLUSIONS: The USCOM showed a poor agreement to TTE measures of CI. The two methods cannot be considered interchangeable.

A Pilot and Feasibility Study of Continuous Cardiac Output and Blood Pressure Monitoring during Intermittent Hemodialysis.

INTRODUCTION: Hypotension is common during intermittent hemodialysis (IHD) and may be due to a decreased cardiac index (CI). However, no study has simultaneously and continuously measured CI and mean arterial pressure (MAP) to understand the prevalence, severity, and duration of CI decreases or relate them to MAP, blood volume (BV), and net ultrafiltration (NUF) rate. METHODS: In a prospective, pilot and feasibility investigation, we studied 10 chronic IHD patients. We used the ClearSight System™ to continuously monitor CI and MAP; the CRIT-LINE®IV monitor to detect BV changes and collected data on NUF rate. RESULTS: Device tolerance and compliance were 100%. All patients experienced at least ≥1 episode of severe CI decrease (>25% from baseline), with a median duration of 24 min (IQR 6-87) and of 68 min [14-106] for moderate decreases (>15% but ≤25% from baseline). Eight patients experienced a low CI state (<2.2 L/min/m2). The lowest CI was 0.9 L/min/m2 with a concomitant MAP of 94 mm Hg. When the fall in CI was severe, MAP increased in 58% of cases and remained stable in 28%. Overall, CI decreased by -0.55 L/min/m2 when BV decrease was moderate versus mild (p < 0.001) and by -0.8 L/min/m2 when NUF rate was high versus low (p < 0.001). CONCLUSION: Continuous CI monitoring is feasible in IHD and shows frequent moderate-severe CI decreases, sometimes to low CI state levels. Such decreases are typically associated with markers of decreased intravascular volume status but not with a decrease in MAP, implying marked vasoconstriction.