Study on the consistency between thoracic electrical bioimpedance and pulse index continuous cardiac output in hemodynamic monitoring of elderly patients with septic shock / 中华老年医学杂志

Objective:The hemodynamic parameters of elderly patients with septic shock were measured simultaneously with pulse index continuous cardiac output(PiCCO)and thoracic electrical bioimpedance(TEB)to evaluate the accuracy of TEB and to provide empirical evidence for its clinical use.Methods:A total of 24 elderly patients with septic shock admitted to the intensive care unit of our hospital between July 2021 and December 2021 were retrospectively recruited.TEB and PiCCO hemodynamic monitoring were performed continuously in all patients, and hemodynamic data were collected for statistical analysis.Results:Cardiac output, cardiac index, stroke volume, stroke index and systemic vascular resistance measured by the two methods had no significant difference( P>0.05). The 95% confidence intervals in the Bland-Altman plots for cardiac output, CI, stroke volume, stroke index, and systemic vascular resistance were(-1.18, 1.25), (-0.65, 0.71), (-24.23, 37.00), (-12.93, 19.26)and(397.11, 425.83). In the Bland-Altman plots for cardiac output, cardiac index, stroke volume and systemic vascular resistance, 4.17% of the points(1/24)fell outside of the 95% confidence interval, and in the Bland-Altman plots for stroke index, 8.33% of the points(2/24)fell outside of the 95% confidence interval. Conclusions:TEB and PiCCO have good consistency in evaluating the hemodynamics of elderly patients with septic shock.Therefore, TEB can be recommended for community hospitals and used in elderly patients.

Role of thoracic electrical bioimpedance monitoring in the evaluation of cardiac function in peritoneal dialysis patients / 中华肾脏病杂志

Objective To evaluate the effectiveness of thoracic electrical bioimpedance(TEB)in monitoring the cardiac function of peritoneal dialysis patients.Methods One hundred and one patients with continuous ambulatory peritoneal dialysis (CAPD) and 30 healthy persons (control group)were included in the study.Thoracic electrical bioimpedance (TEB) noninvasive hcmodynamic monitoring and echocardiography were taken to analyze the correlation between indexes.Results Echocardiography showed that left atrial diameter (LAD),left ventricular end diastolic diameter (LVDd),left ventricular end systolic diameter (LVDs),interventricular septal thickness （IVST),interventricular septal thickness (PAP),left ventricle weight index (LVMI) of CAPD group were higher than that of the control group (all P ＜ 0.05),early and late wave of mitral valve flow (E/A) of CAPD group was lower than that of control group (P ＜ 0.05).TEB monitoring showed that cardiac output (CO),stroke volume (SV),acceleration index (ACI),ejection fraction (EF),velocity index (Ⅵ) of CAPD group were significantly lower than that of control group (all P ＜ 0.01),systolic time ratio (STR),SVR,TFC of CAPD group were significantly higher than that of control group (P ＜ 0.01).Correlation analysis show that left ventricular ejection fraction (LVEF) was negatively correlated with BNP (r =-0.467,P ＜ 0.01),LVMI was positively correlated with BNP (r=0.416,P ＜ 0.01),PEP,STR and TFC were positively correlated with BNP (r =0.404,P ＜ 0.01; r =0.572,P ＜ 0.01; r=0.471,P ＜ 0.01),EF was negatively correlated with BNP (r =-0.664,P ＜ 0.01).Correlation analysis between echocardiogaphy and TEB monitoring index showed there was significant correlation between EF and LVEF (r =0.451,P ＜ 0.01),SVR and TFC were positively correlated with LVMI (r =0.232,P ＜ 0.05; r =0.284,P ＜ 0.05),SV was positively correlated with E/A (r =0.285,P ＜ 0.05),pre-ejection period (PEP) and STR were negatively correlated with LVEF (r =-0.389,P ＜ 0.01; r =-0.446,P ＜ 0.01),TFC was positively correlated with LAD (r=0.279,P ＜ 0.05).Conclusion TEB monitoring can accurately evaluate the cardiac function with the advantage of dynamic monitoring and simple operation.It can partly replace the echocardiography test.

A novel non invasive measurement of hemodynamic parameters: Comparison of single-chamber ventricular and dual-chamber pacemaker.

We carried out a cross sectional study to analyze hemodynamic parameters of single-chamber ventricular pacemaker compared with dual-chamber pacemaker by using thoracic electrical bioimpedance monitoring method (Physio Flow™) - a novel simple non-invasive measurement. A total of 48 consecutive outpatients comprised of 27 single chamber pacemaker and 21 dual chamber were analyzed. We measured cardiac parameters: heart rate, stroke volume index, cardiac output index, estimated ejection fraction, end diastolic volume, early diastolic function ratio, thoracic fluid index, and systemic parameters: left cardiac work index and systemic vascular resistance index. Baseline characteristic and pacemaker indication were similar in both groups. Cardiac parameters assessment revealed no significant difference between single-chamber pacemaker and dual-chamber pacemaker in heart rate, stroke volume index, cardiac index, estimated ejection fraction, end-diastolic volume, thoracic fluid index. There was significantly higher early diastolic function ratio in single-chamber pacemaker compared to dual-chamber pacemaker: 92% (10.2-187.7%) vs. 100.6% (48.7-403.2%); p=0.006. Systemic parameters assessment revealed significantly higher left cardiac work index in single-chamber group than dual-chamber group 4.9 kg.m/m² (2.8-7.6 kg.m/m²) vs. 4.3 kg.m/m² (2.9-7.2 kg.m/m²); p=0.004. There was no significant difference on systemic vascular resistance in single-chamber compared to dual-chamber pacemaker. Single-chamber ventricular pacemaker provides similar stroke volume, cardiac output and left cardiac work, compared to dual-chamber pacemaker. A non-invasive hemodynamic measurement using thoracic electrical bioimpedance is feasible for permanent pacemaker outpatients.

Effect of Small-dose Ketamine on Hemodynamic Changes during Lower Extremity Surgery Using a Tourniquet under General Anesthesia / 대한마취과학회지

BACKGORUND: A tourniquet is commonly used to achieve bloodless field in surgery of the extremities. However, use of tourniquet occasionally has been associated with intraoperative hypertension, but the mechanism of this tourniquet-induced hypertension is unknown. We investigated the effect of preoperative ketamine on tourniquet-induced changes of arterial blood pressure (BP), heart rate (HR), cardiac index (Ci), and systemic vascular resistance index (SVRi). METHODS: Twenty-two patients of ASA physical status class 1 and 2, scheduled for lower extremity surgery using a tourniquet, were randomly assigned into two groups. Anesthesia was maintained with 1.5-2.0 vol% enflurane and 50% N2O in O2 with endotracheal intubation. The changes of BP, HR, Ci, and SVRi were measured (1) at 10 minutes after induction, (2) at 10 minutes after injection of normal saline (control group) or ketamine 0.25 mg/kg, i.v. (ketamine group) before skin incision and tourniquet inflation, (3) at immediately and 5, 10, 15, 20, 30, and 40 minutes after inflation of tourniquet, and (4) immediately after deflation of tourniquet. RESULTS: During tourniquet inflation, BP and HR were not significantly changed in each group and there was no significant differences between the two groups. However, Ci decreased during inflation of the tourniquet in both groups, and it significantly decreased in the control group at the time of 5 and 40 minutes after inflation of tourniquet. SVRi significantly increased during inflation of the tourniquet, and decreased immediately after deflation of the tourniquet in the control group. CONCLUSiONS: We concluded that preoperative iV ketamine, 0.25 mg/kg can prevent tourniquet-induced hemodynamic changes in patients under general anesthesia.

Hemodynamic Effect of Thiopental and Propofol on Endotracheal Intubation: Measurement Using Thoracic Electrical Bioimpedance / 대한마취과학회지

BACKGROUND: The purpose of this study is to delineate hemodynamic changes resulting from endotracheal intubation under the effects of thiopental sodium and propofol using the thoracic electrical bioimpedance device. METHODS: Thirty healthy adult patients, scheduled for elective surgery under general anesthesia were randomly assigned to receive thiopental sodium 5 mg/kg (Group I, N=15), or propofol 2 mg/kg (Group II, N=15) for induction. Endotracheal intubation was performed following injection of succinylcholine 1 mg/kg. Anesthesia was maintained with enflurane 1.5-2.0% and 50% nitrous oxide in oxygen. Cardiovascular parameters were measured before induction of anesthesia, at the time of pre-intubation and immediate, 1, 2, 3 and 5 minutes after intubation. RESULTS: The mean arterial pressure was significantly decreased in the propofol group compared to that of the thiopental sodium group just after the post-intubation period (p<0.05). The heart rate were decreased in both groups but there were no significant changes in heart rate and cardiac output between group I and II. In group I, systemic vascular resistance was decreased but there was no significant changes between two groups. CONCLUSION: The data suggest that the usual doses of propofol could prevent the increase in mean arterial pressure following intubation due to systemic vascular maintenance. But the intubation of anesthesia using thiopental sodium could not prevent the increase in mean arterial pressure following intubation.

Comparison of Hemodynamic Changes by the Thoracic Electrical Bioimpedance Device during Endotracheal Intubation or Insertion of Laryngeal Mask Airway in General Anesthesia / 대한구급학회지

Introduction: we measured the hemodynamic changes by the thoracic electrical bioimpedance (TEB) device during induction of anesthesia, endotracheal intubation or insertion of layngeal mask airway (LMA). This TEB device is safe, reliable and estimate continuously and invasively hemodynamic variables. METHODS: We measured the cardiovascular response of endotracheal intubation or that of LMA insertion in thirty ASA class I patients. General anesthesia was induced with injection of fentany 1 microgram/kg, thiopetal sodium 5 mg/kg and vecuronium 1 mg/kg intravenously. Controlled ventilation was for 3 minutes with inhalation of 50% nitrous oxide and 1.5 vol% of enflurane before tracheal intubation or LMA insertion in all patients. The patient was randomly assinged to either tracheal intubation group (ET group) or laryngeal mask airway group (LMA group). Heart rate (HR), mean arterial pressure (MAP), systemic vascular resistance (SVR), stroke index (SI) and cardic index (CI) were measured to pre-induction, pre-intubation, 1 minute after intubation, 2 minute, 3 minute, 5 minute, 7 minute. RESULTS: MAP and SVR were decreased effectively LMA group than ET group during 1 minute after intubation, 2 minute, 3 minute, 5 minute, 7 minute (p<0.05). HR was decreased effectively LMA group than ET group between pre-induction and 1 minute after intubation, between 1 minute after intubation and 2 minute after intubation (p<0.05). But, SI and CI were no difference between ET group and LMA group during induction of anesthesia and intubation (p<0.05). CONCLUSION: The insertion of LMA is beneficial for certain patients than endotracheal tube to avoid harmful cardiovascular response in the management of airway during anesthesia.