Objective Although goal-directed fluid therapy (GDFT) has been proven to be effective in reducing the incidence of postoperative complications, the underlying mechanisms remain unknown. The aim of this study was to examine the mediating role of intraoperative hemodynamic lability in the association between GDFT and the incidence of postoperative complications. We further tested the role of this mediation effect using mean arterial pressure, a hemodynamic indicator. Methods This secondary analysis used the dataset of a completed nonrandomized controlled study to investigate the effect of GDFT on the incidence of postoperative complications in patients undergoing posterior spine arthrodesis. We used a simple mediation model to test whether there was a mediation effect of average real variability between the association of GDFT and postoperative complications. We conducted mediation analysis using the mediation package in R (version 3.1.2), based on 5,000 bootstrapped samples, adjusting for covariates. Results Among the 300 patients in the study, 40% (120/300) developed postoperative complications within 30 days. GDFT was associated with fewer 30-day postoperative complications after adjustment for confounders (odds ratio: 0.460, 95% CI: 0.278, 0.761; P = 0.003). The total effect of GDFT on postoperative complications was -0.18 (95% CI: -0.28, -0.07; P < 0.01). The average causal mediation effect was -0.08 (95% CI: -0.15, -0.04; P < 0.01). The average direct effect was -0.09 (95% CI: -0.20, 0.03; P = 0.17). The proportion mediated was 49.9% (95% CI: 18.3%, 140.0%). Conclusions The intraoperative blood pressure lability mediates the relationship between GDFT and the incidence of postoperative complications. Future research is needed to clarify whether actively reducing intraoperative blood pressure lability can prevent postoperative complications.
Humans ; Blood Pressure ; Goals ; Postoperative Complications/epidemiology* ; Hemodynamics ; Fluid Therapy/methods*

Introduction: Laparoscopic Cholecystectomy uses carbon dioxide (CO2) which affects the respiratory, cardiovascular and renal system. The residual CO2 induces phrenic nerve irritation, manifesting as shoulder and abdominal pain. Recruitment maneuvers opens the lungs and helps expelling this residual carbon dioxide. However, there are limited studies on its role to hemodynamics especially in patients undergoing abdominal laparoscopic procedures. Methods: Sixty patients (51 15.1) scheduled for laparoscopic cholecystectomy under General Endotracheal Anesthesia were randomly allocated to two groups. The control group (Group C) underwent standard laparoscopic cholecystectomy procedures. The experimental group (Group R) was placed in a Trendelenburg and was given 4-5 manual pulmonary inflations at a pressure of 40cmH20. The blood pressure, heart rate, respiratory rate and oxygen saturation, as well as the post operative site pain and shoulder pain were measured using the Numerical Pain Scale (NPS) were monitored at 0, 1 and 2 hours post operatively. Results: The demographics and preoperative vital signs were comparable. The mean systolic blood pressure [119.5 vs 131.5; p=0.002], mean arterial pressure [91.8 vs 95.3; p=0.049], heart rate [74.9 vs 87.5; p <0.001] and respiratory rate [15.7 vs 16.2; p=0.02] were all differrent only during the immediate post operative period. The mean shoulder pain was lower in Group R immediately [1.9 ± 1.2; p=0.01] and 1 hour after surgery [0.7 ± 0.8; p=0.01]. Conclusion Recruitment maneuver significantly reduces the shoulder pain scores after laparoscopic cholecystectomy. It causes a decrease in blood pressure, heart rate and mean arterial pressure in the immediate post operative period.
Cholecystectomy, Laparoscopic ; Shoulder Pain ; Hemodynamics ; Carbon Dioxide

The patient-specific aortic silicone model was established based on CTA data. The digital particle image velocimetry (DPIV) test method in the modified ViVitro pulsatile flow system was used to investigate the aortic hemodynamic performance and flow field characteristics before and after transcatheter aortic valve replacement (TAVR). The results showed that the hemodynamic parameters were consistent with the clinical data, which verified the accuracy of the model. From the comparative study of preoperative and postoperative effective orifice area (0.33 cm² and 1.78 cm²), mean pressure difference (58 mmHg and 9 mmHg), percentage of regurgitation (52% and 8%), peak flow velocity (4.60 m/s and 1.81 m/s) and flow field distribution (eccentric jet and uniform jet), the immediate efficacy after TAVR is good. From the perspective of viscous shear stress and Reynolds shear stress, the risk of hemolysis and thrombotic problems was low in preoperative and postoperative patient-specific models. This study provides a set of reliable DPIV testing methods for aortic flow field, and provides biomechanical basis for the immediate and long-term effectiveness of TAVR from the perspective of hemodynamics and flow field characteristics. It has important application value in clinical diagnosis, surgical treatment and long-term evaluation.
Humans ; Transcatheter Aortic Valve Replacement/methods* ; Aortic Valve/surgery* ; Heart Valve Prosthesis ; Hemodynamics ; Aortic Valve Stenosis/diagnosis* ; Treatment Outcome

INTRODUCTION: Umbilical cord milking (UCM) is a method that allows for postnatal placental transfusion. The benefits of UCM have been demonstrated in some studies, but knowledge about its haemodynamic effects in term infants is limited. The aim of this study was to evaluate the haemodynamic effects of UCM in term infants. METHODS: In this prospective, randomised controlled study, 149 healthy term infants with a birth week of ≥37 weeks were randomly assigned to either the UCM or immediate cord clamping (ICC) group. Blinded echocardiographic evaluations were performed in all the neonates in the first 2-6 h. RESULTS: Superior vena cava (SVC) flow measurements were higher in the UCM group compared to the ICC group (132.47 ± 37.0 vs. 126.62 ± 34.3 mL/kg/min), but this difference was not statistically significant. Left atrial diameter (12.23 ± 1.99 vs. 11.43 ± 1.78 mm) and left atrium-to-aorta diastolic diameter ratio (1.62 ± 0.24 vs. 1.51 ± 0.22) were significantly higher in the UCM group. There were no significant differences in other echocardiographic parameters between the two groups. CONCLUSION We found no significant difference in the SVC flow measurements in term infants who underwent UCM versus those who underwent ICC. This lack of significant difference in SVC flow may be explained by the mature cerebral autoregulation mechanism in term neonates.
Infant, Newborn ; Infant ; Humans ; Pregnancy ; Female ; Infant, Premature/physiology* ; Umbilical Cord Clamping ; Prospective Studies ; Vena Cava, Superior/diagnostic imaging* ; Placenta ; Umbilical Cord/physiology* ; Constriction ; Hemodynamics/physiology*

Endovascular treatment of Stanford type B aortic dissection (type B dissection) has been widely used. There will be complications such as aortic dilatation, which will lead to poor prognosis of some patients. With more in-depth researches, it was found that there was a possible correlation between the prognosis of type B dissection and tears, such as the increasing of aortic diameter would be faster with longer tears, and the location of the tear will affect the thrombosis of the false lumen. Studies on hemodynamics have also found that different characteristics of tears of aortic dissection can cause changes in the pressure, blood flow rate and blood capacity in the true and false lumens recently. The hemodynamic changes can be used to predict the prognosis of type B dissection. The main characteristics of tears included the size, position, number of tears, residual tears and stent graft induced new entry. Describing the effect of tear characteristics on the development of type B dissection, can provide the basis for the clinical treatment and further research of type B dissection.
Humans ; Aortic Dissection/surgery* ; Hemodynamics ; Prognosis ; Blood Vessel Prosthesis Implantation/adverse effects* ; Thrombosis/etiology* ; Endovascular Procedures/adverse effects* ; Aortic Aneurysm, Thoracic/surgery* ; Stents/adverse effects* ; Treatment Outcome

Objective To analyze the risk factors and build a clinical prediction model for hemodynamic depression (HD) after carotid artery stenting (CAS). Methods A total of 116 patients who received CAS in the Department of Vascular Surgery,Drum Tower Clinical College of Nanjing Medical University and the Department of Vascular Surgery,the Affiliated Suqian First People's Hospital of Nanjing Medical University from January 1,2016 to January 1,2022 were included in this study.The patients were assigned into a HD group and a non-HD group.The clinical baseline data and vascular disease characteristics of each group were collected,and multivariate Logistic regression was employed to identify the independent predictors of HD after CAS and build a clinical prediction model.The receiver operating characteristic (ROC) curve was drawn,and the area under the ROC curve (AUC) was calculated to evaluate the predictive performance of the model. Results The HD group had lower proportions of diabetes (P=0.014) and smoking (P=0.037) and higher proportions of hypertension (P=0.031),bilateral CAS (P=0.018),calcified plaque (P=0.001),eccentric plaque (P=0.003),and the distance<1 cm from the minimum lumen level to the carotid bifurcation (P=0.009) than the non-HD group.The age,sex,coronary heart disease,symptomatic carotid artery stenosis,degree of stenosis,and length of lesions had no statistically significant differences between the HD group and the non-HD group (all P>0.05).Based on the above predictive factors,a clinical prediction model was established,which showed the AUC of 0.807 and the 95% CI of 0.730-0.885 (P<0.001).The model demonstrated the sensitivity of 62.7% and the specificity of 87.7% when the best cut-off value of the model score reached 12.5 points. Conclusions Diabetes,smoking,calcified plaque,eccentric plaque,and the distance<1 cm from the minimum lumen level to the carotid bifurcation are independent predictors of HD after CAS.The clinical prediction model built based on the above factors has good performance in predicting the occurrence of HD after CAS.
Humans ; Carotid Stenosis ; Depression ; Models, Statistical ; Prognosis ; Stents ; Hemodynamics ; Plaque, Amyloid

Objective Dexmedetomidine is a highly selective alpha-2 adrenergic receptor agonist with sedative and analgesic properties but without respiratory depression effect and has been widely used in perioperative anesthesia. Here we performed a systematic review and meta-analysis to evaluate the effect of dexmedetomidine on maintaining perioperative hemodynamic stability in elderly patients.Methods PubMed, Web of Science, the Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang Data were searched for randomized-controlled trials (RCTs) on the application of dexmedetomidine in maintaining perioperative hemodynamic stability in elderly patients from their inception to September, 2021. The standardized mean differences (SMD) with 95% confidence interval (CI) were employed to analyze the data. The random-effect model was used for the potential clinical inconsistency.Results A total of 12 RCTs with 833 elderly patients (dexmedetomidine group, 546 patients; control group, 287 patients) were included. There was no significant increase in perioperative heart rate (HR), mean arterial pressure (MAP), and diastolic blood pressure (DBP) in the dexmedetomidine group before and during the operation. In addition, the variations of hemodynamic indexes including HR, MAP, SBP (systolic blood pressure), and DBP were significantly lower in the dexmedetomidine group compared with the control group (HR: SMD = -0.87, 95% CI: -1.13 to -0.62; MAP: SMD = -1.12, 95% CI: -1.60 to -0.63; SBP: SMD = -1.27, 95% CI: -2.26 to -0.27; DBP: SMD = -0.96, 95% CI: -1.33 to -0.59). Subgroup analysis found that with the prolongation of 1.0 μg/kg dexmedetomidine infusion, the patient's heart rate declined in a time-dependent way.Conclusion Dexmedetomidine provides more stable hemodynamics during perioperative period in elderly patients. However, further well-conducted trials are required to assess the effective and safer doses of dexmedetomidine in elderly patients.
Humans ; Aged ; Dexmedetomidine/adverse effects* ; Hemodynamics ; Hypnotics and Sedatives/pharmacology* ; Blood Pressure ; Heart Rate

By using Doppler sensor and pressure sensor, the cerebrovascular stroke detector can be used to measure the blood flow velocity and blood pressure of the carotid artery. In this study, a variety of signal conversion and isolation processing techniques are proposed for processing and feature extraction of the output signals from the sensors. Finally, effective signal output waveforms that can be used to evaluate the cerebrovascular hemodynamics index (CVHI) are obtained, and the sound signal outputs that can reflect the change characteristics of blood flow velocity and blood pressure signals are generated, which realizes the application functional requirements of the detector.
Blood Flow Velocity/physiology* ; Cerebrovascular Circulation/physiology* ; Hemodynamics/physiology* ; Humans ; Stroke ; Technology

Echocardiogram is vital for the diagnosis of cardiac disease. The heart has complex hemodynamics requiring an advanced ultrasound imaging mode. Cardiac ultrasound vector flow imaging is capable of measuring the actual magnitude and direction of the blood flow velocity, obtaining the quantitative parameters of hemodynamics, and then providing more information for clinical research and diagnosis. This study mainly reviewed several different vector flow imaging techniques for cardiac flow and presented the implementation difficulties, and proposed a diverging wave based high frame rate cardiac ultrasound vector flow imaging. The study discussed the limitation of current ultrasound technology used in the cardiac flow measurement, analyzed and demonstrated the specific reasons for these implementation difficulties and the potential future development.
Blood Flow Velocity ; Heart/physiology* ; Hemodynamics ; Ultrasonography

OBJECTIVE: To compare the effect of micro-needle knife therapy and betahistine mesilate tablets in the treatment of cervical vertigo (CV) and the influence on the mean blood flow velocity (Vm) of vertebral artery. METHODS: A total of 200 patients with CV were randomly divided into a micro-needle knife group (100 cases, 5 cases dropped off) and a medication group (100 cases, 3 cases dropped off). In the micro-needle knife group, micro-needle knife was performed on the suboccipital triangle of the atlantoaxial segment of the posterior neck, once every other day, for a total of 7-time treatment. The medication group received oral betahistine mesilate tablets, 6 mg each time, three times a day, for 14 consecutive days. The dizziness handicap inventory (DHI) scores of the two groups were observed before treatment, after treatment and during follow-up 3 months after treatment; the Vm of vertebral artery was compared between the two groups before and after treatment, and the clinical effect was evaluated during follow-up. RESULTS: After treatment and during follow-up, the DHI scores of the two groups were lower than those before treatment (P<0.001), and those in the micro-needle knife group were lower than the medication group (P<0.001). After treatment, the Vm of bilateral vertebral arteries in both groups was higher than that before treatment (P<0.05), and that in the micro-needle knife group was higher than the medication group (P<0.05). The total effective rate of the micro-needle knife group was 96.8% (92/95), which was higher than 67.0% (65/97) of the medication group (P<0.001). CONCLUSION Micro-needle knife therapy can improve vertigo symptoms and balance dysfunction, increase the mean blood flow velocity of vertebral artery in CV patients, and its clinical efficacy is better than oral betahistine mesilate tablets.
Betahistine ; Hemodynamics ; Humans ; Mesylates ; Treatment Outcome ; Vertebral Artery ; Vertigo/therapy*