BACKGROUND: It is still unclear what the minimal infusion volume is to effectively predict fluid responsiveness. This study was designed to explore the minimal infusion volume to effectively predict fluid responsiveness in septic shock patients. Hemodynamic effects of fluid administration on arterial load were observed and added values of effective arterial elastance (Ea) in fluid resuscitation were assessed. METHODS: Intensive care unit septic shock patients with indwelling pulmonary artery catheter (PAC) received five sequential intravenous boluses of 100 mL 4% gelatin. Cardiac output (CO) was measured with PAC before and after each bolus. Fluid responsiveness was defined as an increase in CO >10% after 500 mL fluid infusion. RESULTS: Forty-seven patients were included and 35 (74.5%) patients were fluid responders. CO increasing >5.2% after a 200 mL fluid challenge (FC) provided an improved detection of fluid responsiveness, with a specificity of 80.0% and a sensitivity of 91.7%. The area under the ROC curve (AUC) was 0.93 (95% CI: 0.84-1.00, P  < 0.001). Fluid administration induced a decrease in Ea from 2.23 (1.46-2.78) mmHg/mL to 1.83 (1.34-2.44) mmHg/mL (P = 0.002), especially for fluid responders in whom arterial pressure did not increase. Notably, the baseline Ea was able to detect the fluid responsiveness with an AUC of 0.74 (95% CI: 0.59-0.86, P < 0.001), whereas Ea failed to predict the pressure response to FC with an AUC of 0.50 (95% CI: 0.33-0.67, P = 0.086). CONCLUSION: In septic shock patients, a minimal volume of 200 mL 4% gelatin could reliably detect fluid responders. Fluid administration reduced Ea even when CO increased. The loss of arterial load might be the reason for patients who increased their CO without pressure responsiveness. Moreover, a high level of Ea before FC was able to predict fluid responsiveness rather than to detect the pressure responsiveness. TRIAL REGISTRATION ClinicalTrials.gov, NCT04515511.
Cardiac Output/physiology* ; Fluid Therapy ; Gelatin/therapeutic use* ; Hemodynamics ; Humans ; Shock, Septic/therapy*

OBJECTIVE: To study the changes in hemodynamics during the induction stage of systemic mild hypothermia therapy in neonates with moderate to severe hypoxic-ischemic encephalopathy (HIE). METHODS: A total of 21 neonates with HIE who underwent systemic mild hypothermia therapy in the Department of Neonatology, Dongguan Children's Hospital Affiliated to Guangdong Medical University, from July 2017 to April 2020 were enrolled. The rectal temperature of the neonates was lowered to 34℃ after 1-2 hours of induction and maintained at this level for 72 hours using a hypothermia blanket. The impedance method was used for noninvasive hemodynamic monitoring, and the changes in heart rate (HR), mean arterial pressure (MAP), stroke volume (SV), cardiac output (CO), cardiac index (CI), and total peripheral resistance (TPR) from the start of hypothermia induction to the achievement of target rectal temperature (34℃). Blood lactic acid (LAC) and resistance index (RI) of the middle cerebral artery were recorded simultaneously. RESULTS: The 21 neonates with HIE had a mean gestational age of (39.6±1.1) weeks, a mean birth weight of (3 439±517) g, and a mean 5-minute Apgar score of 6.8±2.0. From the start of hypothermia induction to the achievement of target rectal temperature (34℃), there were significant reductions in HR, CO, and CI ( CONCLUSIONS The systemic mild hypothermia therapy may have a significant impact on hemodynamics in neonates with moderate to severe HIE, and continuous hemodynamic monitoring is required during the treatment.
Cardiac Output ; Child ; Hemodynamics ; Humans ; Hypothermia ; Hypoxia-Ischemia, Brain/therapy* ; Infant ; Infant, Newborn ; Vascular Resistance

Objective: To explore the risk factors of low cardiac output syndrome (LCOS) after cardiac valvular surgery in elderly patients with valvular disease complicated with giant left ventricle. Methods: This was a retrospective study. The clinical data of patients over 60 years old with giant left ventricle who underwent cardiac valvular surgery in Henan Provincial People's Hospital (Fuwai Central China Cardiovascular Hospital) from January 2016 to January 2020 were collected in this study. Patients were divided into LCOS group and non-LCOS group. The clinical data, preoperative echocardiographic results and surgical data of all patients were collected. Taking LCOS as dependent variable and statistically significant variables in univariate analysis as independent variable, multivariate logistic regression equation was constructed to identify the risk factors of LCOS after cardiac valvular surgery in elderly patients with valvular disease complicated with giant left ventricle. On the basis of logistic regression, the risk factors of continuous variables were put into the regression model for trend test. Results: A total of 112 patients were included, among whom 76 patients were male, the mean age was (65.3±3.8) years. There were 21 cases in LCOS group and 91 cases in non LCOS group. Univariate analysis showed that age≥70 years, preoperative NYHA cardiac function class Ⅳ, preoperative renal dysfunction, preoperative cerebrovascular disease, preoperative LVEF<40%, blood loss/total blood volume>20%, cardiopulmonary bypass (CPB) time>130 minutes and aortic cross-clamp time>90 minutes all had statistically significant differences between the two groups (all P<0.05). Multivariate logistic regression analysis showed that age≥70 years (OR=5.067, 95%CI 1.320-19.456, P=0.018), preoperative NYHA cardiac function class Ⅳ (OR=3.100, 95%CI 1.026-9.368, P=0.045), renal dysfunction (OR=3.627, 95%CI 1.018-12.926, P=0.047), CPB time>130 minutes (OR=4.539, 95%CI 1.483-13.887, P=0.008) were the independent risk factors of LCOS after cardiac valvular surgery in elderly patients with giant left ventricle. Risk of LCOS was significantly higher in patients aged from 65 to 70 years (OR=1.784, 95%CI 0.581-5.476) and aged 70 years and above (OR=4.400, 95%CI 1.171-16.531) than in patients aged from 60 to 65 years. The trend test results showed that the risk of LCOS increased significantly in proportion with the increase of age (P for trend=0.024). Risk of LCOS was significantly higher in patients with CPB time between 90 and 110 minutes (OR=1.917, 95%CI 0.356-10.322), 110 and 130 minutes (OR=1.437, 95%CI 0.114-18.076) and 130 minutes and above (OR=5.750, 95%CI 1.158-28.551) than in patients with CPB time ≤ 90 minutes (P for trend=0.009). Conclusions: The risk factors of LCOS after cardiac valvular surgery are age≥70 years, preoperative NYHA cardiac function class Ⅳ, renal dysfunction, CPB time>130 minutes in elderly patients with giant left ventricle.
Aged ; Cardiac Output, Low/etiology* ; China ; Female ; Heart Valve Diseases ; Heart Ventricles/diagnostic imaging* ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Risk Factors

BACKGROUND: The assessment of intravascular volume status is very important especially in children during anesthesia. Pulse pressure variation (PPV) and pleth variability index (PVI) are well known parameters for assessing intravascular volume status and fluid responsiveness. We compared PPV and PVI for children aged less than two years who underwent surgery in the prone position. METHODS: A total of 27 children were enrolled. We measured PPV and PVI at the same limb during surgery before and after changing the patients’ position from supine to prone. We then compared PPV and PVI at each period using Bland-Altman plot for bias between the two parameters and for any correlation. We also examined the difference between before and after the position change for each parameter, along with peak inspiratory pressure, heart rate and mean blood pressure. RESULTS: The bias between PPV and PVI was −2.2% with a 95% limits of agreement of −18.8% to 14.5%, not showing significant correlation at any period. Both PPV and PVI showed no significant difference before and after the position change. CONCLUSIONS: No significant correlation between PVI and PPV was observed in children undergoing surgery in the prone position. Further studies relating PVI, PPV, and fluid responsiveness via adequate cardiac output estimation in children aged less than 2 years are required.
Anesthesia ; Arterial Pressure ; Bias (Epidemiology) ; Blood Pressure ; Cardiac Output ; Child ; Extremities ; Fluid Therapy ; Heart Rate ; Humans ; Plethysmography ; Prone Position

It is challenging to predict fluid responsiveness, that is, whether the cardiac index or stroke volume index would be increased by fluid administration, in the pediatric population. Previous studies on fluid responsiveness have assessed several variables derived from pressure wave measurements, plethysmography (pulse oximeter plethysmograph amplitude variation), ultrasonography, bioreactance data, and various combined methods. However, only the respiratory variation of aortic blood flow peak velocity has consistently shown a predictive ability in pediatric patients. For the prediction of fluid responsiveness in children, flow- or volume-dependent, noninvasive variables are more promising than pressure-dependent, invasive variables. This article reviews various potential variables for the prediction of fluid responsiveness in the pediatric population. Differences in anatomic and physiologic characteristics between the pediatric and adult populations are covered. In addition, some important considerations are discussed for future studies on fluid responsiveness in the pediatric population.
Adult ; Blood Pressure ; Cardiac Output ; Child ; Fluid Therapy ; Humans ; Oximetry ; Plethysmography ; Pulse Wave Analysis ; Stroke Volume ; Ultrasonography ; Ultrasonography, Doppler

BACKGROUND: Vasoplegic syndrome is an increasingly recognized disease in perioperative medicine and is characterized by severe hypotension, normal or elevated cardiac output, and decreased systemic vascular resistance. It occurs commonly after cardiopulmonary bypass but may also occur after other types of surgery.CASE: Vasoplegic syndrome developed in our patient during posterior lumbar interbody fusion because of administering nicardipine after phenylephrine. However, the blood pressure did not increase as expected despite simultaneous use of norepinephrine and vasopressin to increase the reduced systemic vascular resistance.CONCLUSIONS: We present a case of vasoplegic syndrome that developed during posterior lumbar interbody fusion and was treated successfully with methylene blue.
Blood Pressure ; Cardiac Output ; Cardiopulmonary Bypass ; Humans ; Hypotension ; Methylene Blue ; Nicardipine ; Norepinephrine ; Phenylephrine ; Vascular Resistance ; Vasoplegia ; Vasopressins

BACKGROUND: Controlled hypotension (CH) provides a better surgical environment and reduces operative time. However, there are some risks related to organ hypoperfusion. The EV1000/FloTrac system can provide continuous cardiac output monitoring without the insertion of pulmonary arterial catheter. The present study investigated the efficacy of this device in double jaw surgery under CH.METHODS: We retrospectively reviewed the medical records of patients who underwent double jaw surgery between 2010 and 2015. Patients were administered conventional general anesthesia with desflurane; CH was performed with remifentanil infusion and monitored with an invasive radial arterial pressure monitor or the EV1000/FloTrac system. We allocated the patients into two groups, namely an A-line group and an EV1000 group, according to the monitoring methods used, and the study variables were compared.RESULTS: Eighty-five patients were reviewed. The A-line group reported a higher number of failed CH (P = 0.005). A significant correlation was found between preoperative hemoglobin and intraoperative packed red blood cell transfusion (r = 0.525; P < 0.001). In the EV1000 group, the mean arterial pressure (MAP) was significantly lower 2 h after CH (P = 0.014), and the cardiac index significantly decreased 1 h after CH (P = 0.001) and 2 h after CH (P = 0.007). Moreover, venous oxygen saturation (ScVO2) decreased significantly at both 1 h (P = 0.002) and 2 h after CH (P = 0.029); however, these values were within normal limits.CONCLUSION: The EV1000 group reported a lower failure rate of CH than the A-line group. However, EV1000/FloTrac monitoring did not present with any specific advantage over the conventional arterial line monitoring when CH was performed with the same protocol and same mean blood pressure. Preoperative anemia treatment will be helpful to decrease intraoperative transfusion. Furthermore, ScVO2 monitoring did not present with sufficient benefits over the risk and cost.
Anemia ; Anesthesia, General ; Arterial Pressure ; Blood Pressure ; Cardiac Output ; Catheters ; Erythrocyte Transfusion ; Humans ; Hypotension, Controlled ; Medical Records ; Operative Time ; Orthognathic Surgery ; Osteotomy, Le Fort ; Oxygen ; Retrospective Studies ; Vascular Access Devices

To investigate the effect of controlled hypotension by urapidil on the predictive accuracy and diagnostic threshold of stroke volume variation (SVV) in hypertensive and non-hypertensive patients undergoing robotic hepatobiliary surgery.
 Methods: Eighty patients undergoing robotic hepatobiliary surgery under general anesthesia were divided into a hypertension group (n=25) and a non-hypertension group (n=38) according to whether or not essential hypertension was present (excluding some cases that didn't meet requirements). The pump speed was at 6.0-7.0 µg/(kg﹒min), and the range of hypotension was between 10%≤Δ systolic blood pressure (SAP)≤20%. Volume loading test was performed after artificial pneumoperitoneum was established in reverse-Trendelenburg position. Hemodynamic indexes including heart rate (HR), SAP, cardiac output (CO), cardiac index (CI), stroke volume (SV), stroke volume index (SVI) and SVV were recorded before and after infusion. Then the receiver operating characteristic (ROC) curves of SVV was drawn to determine the accuracy and diagnosis of SVV in predicting volume status in hypertensive and non-hypertensive patients after anti-Trendelenburg posture and pneumoperitoneum.
 Results: In the patients with controlled hypotension by urapidil, the area under the ROC curve of SVV in the hypertension group was 0.974, the diagnostic threshold was 13.5%, the ROC curve of SVV in the non-hypertension group was 0.832, and the diagnostic threshold was 15.5%.
 Conclusion: SVV can accurately predict the volume status in the hypertension group and the non-hypertension group after controlled hypotension in the anti-Trendelenburg position and fixed pneumoperitoneal pressure, and the SVV diagnostic threshold in the non-hypertensive group is higher than that in the hypertensive group.
Biliary Tract Diseases ; surgery ; Blood Pressure ; Cardiac Output ; Fluid Therapy ; Hemodynamics ; Humans ; Hypotension, Controlled ; Liver Diseases ; surgery ; ROC Curve ; Robotic Surgical Procedures ; Stroke ; Stroke Volume

OBJECTIVE: Stroke volume (SV) measurements have been used to guide fluid management. Noninvasive, indirect, and convenient measurements of the SV for fluid therapy are required for most patients during spontaneous breathing (SB). On the other hand, the preferred method for an indirect prediction of the SV is unclear. This study examined the best of the indirect and predictable parameters responding to a SV variation during SB. METHODS: Hemodynamic parameters, such as collapsibility of the inferior vena cava (cIVC), peak velocity variation in the common carotid artery (pvvCCA), collapsibility of the internal jugular vein (cIJV), and end-tidal carbon dioxide (ETCO₂) were measured 180 times (6 different positions each in 30 normal subjects). The variables changed with the SV at the upper body elevation of 60°and 30°, in the supine position, at the lower body elevation of 60°and 30°, and lumbar elevation. RESULTS: The SV showed the highest value at 30°of lower body elevation. Following fixed position changes, the ETCO₂ during SB was the factor most correlated with the SV when compared to cIVC, cIJV, and pvvCCA (β coefficient, 2.432 vs. −0.41, −0.033, and −0.654; P=0.004). The adjusted ETCO₂ showed a significant change with the SV, even though the change in ETCO₂ was not large. CONCLUSION: ETCO₂ was less influenced by the SB than cIVC, pvvCCA, and cIJV because the ETCO₂ change was in accordance but the variations of the other blood vessels did not coincide with a SV change. Therefore, ETCO₂ monitoring for predicting the SV would be more important than the variations in the vessels during SB.
Blood Vessels ; Carbon Dioxide ; Carbon ; Cardiac Output ; Carotid Artery, Common ; Fluid Therapy ; Hand ; Hemodynamics ; Humans ; Jugular Veins ; Methods ; Respiration ; Stroke Volume ; Stroke ; Supine Position ; Ultrasonography ; Vena Cava, Inferior

Chronic mitral valve disease (CMVD) is the most common cardiovascular disease in dogs, causing decreased cardiac output that results in poor tissue perfusion and tissue damage to kidneys, pancreas, and other organs. The purpose of this study was to evaluate the relationships between heart disease severity and N-terminal pro B-type natriuretic peptide (NT-proBNP) and lipase in dogs with CMVD, as well as to evaluate longitudinal changes in these values. A total of 84 dogs participated in this 2015 to 2017 study. Serum values of NT-proBNP and lipase were analyzed; radiography was used to measure the vertebral heart score and assess various echocardiographic values. NT-proBNP showed a strong positive correlation with increasing stage of heart disease; lipase showed a mild positive correlation with heart disease stage. When the three values (NT-proBNP, lipase and month) were continuously measured at 6-month intervals, all showed a correlation with the increasing length of the disease.
Animals ; Cardiac Output ; Cardiovascular Diseases ; Dogs ; Echocardiography ; Heart ; Heart Diseases ; Kidney ; Lipase ; Mitral Valve ; Natriuretic Peptide, Brain ; Pancreas ; Perfusion ; Radiography