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

OBJECTIVE: To investigate the regional flow distribution in patients with Fontan circulation by using magnetic resonance imaging (MRI). MATERIALS AND METHODS: We identified 39 children (18 females and 21 males; mean age, 9.3 years; age range, 3.3–17.0 years) with Fontan circulation in whom flow volumes across the thoracic and abdominal arteries and veins were measured by using MRI. The patients were divided into three groups: fenestrated Fontan circulation group with MRI performed under general anesthesia (GA) (Group 1, 15 patients; average age, 5.9 years), completed Fontan circulation group with MRI performed under GA (Group 2, 6 patients; average age, 8.7 years), and completed Fontan circulation group with MRI performed without GA (Group 3, 18 patients; average age, 12.5 years). The patient data were compared with the reference ranges in healthy controls. RESULTS: In comparison with the controls, Group 1 showed normal cardiac output (3.92 ± 0.40 vs. 3.72 ± 0.69 L/min/m2, p = 0.30), while Group 3 showed decreased cardiac output (3.24 ± 0.71 vs. 3.96 ± 0.64 L/min/m2, p = 0.003). Groups 1 and 3 showed reduced abdominal flow (1.21 ± 0.28 vs. 2.37 ± 0.45 L/min/m2, p < 0.001 and 1.89 ± 0.39 vs. 2.64 ± 0.38 L/min/m2, p < 0.001, respectively), which was mainly due to the diversion of the cardiac output to the aortopulmonary collaterals in Group 1 and the reduced cardiac output in Group 3. Superior mesenteric and portal venous flows were more severely reduced in Group 3 than in Group 1 (ratios between the flow volumes of the patients and healthy controls was 0.26 and 0.37 in Group 3 and 0.63 and 0.53 in Group 1, respectively). Hepatic arterial flow was decreased in Group 1 (0.11 ± 0.22 vs. 0.34 ± 0.38 L/min/m2, p = 0.04) and markedly increased in Group 3 (0.38 ± 0.22 vs. −0.08 ± 0.29 L/min/m2, p < 0.0001). Group 2 showed a mixture of the patterns seen in Groups 1 and 3. CONCLUSION: Fontan circulation is associated with reduced abdominal flow, which can be attributed to reduced cardiac output and portal venous return in completed Fontan circulation, and diversion of the cardiac output to the aortopulmonary collaterals in fenestrated Fontan circulation.
Anesthesia, General ; Arteries ; Cardiac Output ; Child ; Female ; Fontan Procedure ; Humans ; Magnetic Resonance Imaging ; Male ; Protein-Losing Enteropathies ; Reference Values ; Veins

A 2.5-kg neonate with coarctation of the aorta and a small left ventricle experienced a severe pulmonary hypertensive crisis. An emergency pulmonary artery-to-systemic artery shunt was placed to break the positive feedback loop caused by pulmonary hypertension and functional mitral stenosis. This shunt provided immediate relief of suprasystemic pulmonary hypertension and the resultant low cardiac output.
Aortic Coarctation ; Arteries ; Cardiac Output, Low ; Emergencies ; Heart Ventricles ; Humans ; Hypertension, Pulmonary ; Hypoplastic Left Heart Syndrome ; Infant, Newborn ; Mitral Valve Stenosis

PURPOSE: The most common method of monitoring cardiac output (CO) is thermodilution using pulmonary artery catheter (PAC), but this method is associated with complications. Impedance cardiography (ICG) is a non-invasive CO monitoring technique. This study compared the accuracy and efficacy of ICG as a non-invasive cardiac function monitoring technique to those of thermodilution and arterial pressure contour. MATERIALS AND METHODS: Sixteen patients undergoing liver transplantation were included. Cardiac index (CI) was measured by thermodilution using PAC, arterial waveform analysis, and ICG simultaneously in each patient. Statistical analysis was performed using intraclass correlation coefficient (ICC) and Bland-Altman analysis to assess the degree of agreement. RESULTS: The difference by thermodilution and ICG was 1.13 L/min/m², and the limits of agreement were −0.93 and 3.20 L/min/m². The difference by thermodilution and arterial pressure contour was 0.62 L/min/m², and the limits of agreement were −1.43 and 2.67 L/min/m². The difference by arterial pressure contour and ICG was 0.50 L/min/m², and the limits of agreement were −1.32 and 2.32 L/min/m². All three percentage errors exceeded the 30% limit of acceptance. Substantial agreement was observed between CI of thermodilution with PAC and ICG at preanhepatic and anhepatic phases, as well as between CI of thermodilution and arterial waveform analysis at preanhepatic phase. Others showed moderate agreement. CONCLUSION: Although neither method was clinically equivalent to thermodilution, ICG showed more substantial correlation with thermodilution method than with arterial waveform analysis. As a non-invasive cardiac function monitor, ICG would likely require further studies in other settings.
Arterial Pressure ; Cardiac Output ; Cardiography, Impedance ; Catheters ; Electric Impedance ; Humans ; Liver Transplantation ; Methods ; Pulmonary Artery ; Thermodilution

BACKGROUND: The objective of this study was to compare the frequency of hypotension and immediate hemodynamic changes induced by unilateral and bilateral spinal anesthesia in hypertensive elderly patients. METHODS: Forty hypertensive elderly patients undergoing lower leg surgery were randomly allocated into unilateral (group US) and bilateral spinal anesthesia (group BS). After intrathecal bupivacaine injection, patients in group US were kept in the lateral position for 10 min while patients in group BS were immediately placed in the supine position. Hemodynamic parameters were measured for 20 min by non-invasive cardiac output monitor based on bioreactance. RESULTS: In both groups, mean arterial pressure was significantly decreased after spinal anesthesia compared to the baseline value. However, frequency of hypotension requiring vasoactive drug was significantly lower in group US (5%) than in group BS (35%) (P = 0.044). The dermatom of sensory block on the operated limb was significantly lower in group US [T10 (10–10)] than in group BS [T8 (7.5–10)] (P = 0.013). In comparison within the group, changes of cardiac index were similar as the baseline value in both groups, although total peripheral resistance index was constant in group US but significantly decreased in group BS. CONCLUSIONS: Unilateral spinal anesthesia effectively reduced the frequency of hypotension requiring vasoactive drug and affected hemodynamic performance less than bilateral spinal anesthesia.
Aged ; Anesthesia, Spinal ; Arterial Pressure ; Bupivacaine ; Cardiac Output ; Extremities ; Hemodynamics ; Humans ; Hypertension ; Hypotension ; Leg ; Supine Position ; Vascular Resistance

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

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