Diagnostic value of non-invasive cardiac output parameters in premature infants with patent ductus ;arteriosus / 中华围产医学杂志

Objective To investigate the diagnostic value of non-invasive cardiac output parameters:cardiac index (CI) and minute distance (MD), in premature infants with patent ductus arteriosus (PDA) and determine the cut-off value. Methods Clinical data of 98 premature infants admitted to the neonatal intensive care unit from January 2015 to June 2015 were collected. These premature infants were divided into the treated PDA group (n=30),the untreated PDA group (n=28) and the normal premature group (n=40) based on the results of echocardiogram in the first three days after birth and the use of drugs. Non-invasive cardiac output parameters were measured in the first three days after birth. The data were analyzed by t test, analysis of variance and SNK-q test. The diagnostic value of CI and MD for PDA was analyzed by the receiver operating characteristic curve. Results By preliminary analysis of the ROC curve,CI and MD were the most representative parameters for the diagnosis of PDA which need to be treated clinically, we thus chose CI and MD in this study. The aortic and pulmonary arterial CI and MD in the treated PDA group were significantly higher than in the untreated PDA group and the normal premature group (all P0.05). The cut-off value of the aortic CI and MD was 2.95 L/(min·m2) and 21.50 m/min, respectively, while that of the pulmonary arterial CI and MD was 4.55 L/(min·m2) and 26.50 m/min, respectively. The sensitivity and specificity of the combined aortic CI and MD for the treated PDA group were 0.90 and 0.82, and those of combined pulmonary arterial CI and MD were 0.87 and 0.82;and those of combined aortic and pulmonary arterial CI and MD were 0.80 and 0.88, respectively. Conclusions The non-invasive cardiac output parameters CI and MD have good diagnostic value for the PDA needing clinical treatment, and the combined use of the two parameters can improve specificity, and help formulate the early treatment strategy for premature infants with PDA. When aortic CI was ≥ 2.95 L/(min·m2) and MD was ≥ 21.50 m/min, a preliminary diagnosis of the PDA needing clinical treatment, can be made, and simultaneously when the pulmonary arterial CI was ≥4.55 L/(min·m2) and MD was≥26.50 m/min, the arterial duct should be closed timely.

Efficacy of Goal-Directed Therapy Using Bioreactance Cardiac Output Monitoring after Valvular Heart Surgery

PURPOSE: We compared the efficacy of postoperative hemodynamic goal-directed therapy (GDT) using a pulmonary artery catheter (PAC) and bioreactance-based noninvasive cardiac output monitoring (NICOM) in patients with atrial fibrillation undergoing valvular heart surgery. MATERIALS AND METHODS: Fifty eight patients were randomized into two groups of GDT with common goals to maintain a mean arterial pressure of 60-80 mm Hg and cardiac index > or =2 L/min/m2: the PAC group (n=29), based on pulmonary capillary wedge pressure, and the NICOM group (n=29), based on changes in stroke volume index after passive leg raising. The primary efficacy variable was length of hospital stay. Secondary efficacy variables included resource utilization including vasopressor and inotropic requirement, fluid balance, and major morbidity endpoints. RESULTS: Patient characteristics and operative data were similar between the groups, except that significantly more patients underwent double valve replacement in the NICOM group. The lengths of hospital stay were not different between the two groups (12.2+/-4.8 days vs. 10.8+/-4.0 days, p=0.239). Numbers of patients requiring epinephrine (5 vs. 0, p=0.019) and ventilator care >24 h (6 vs. 1, p=0.044) were significantly higher in the PAC group. The PAC group also required significantly larger amounts of colloid (1652+/-519 mL vs. 11430+/-463 mL, p=0.004). CONCLUSION: NICOM-based postoperative hemodynamic GDT showed promising results in patients with atrial fibrillation undergoing valvular heart surgery in terms of resource utilization.

Comparison between continuous non-invasive estimated cardiac output by pulse wave transit time and thermodilution method.

Aims and Objectives: Cardiac output (CO) measurement is essential for many therapeutic decisions in anesthesia and critical care. Most available non‑invasive CO measuring methods have an invasive component. We investigate “pulse wave transit time” (estimated continuous cardiac output [esCCO]) a method of CO measurement that has no invasive component to its use. Materials and Methods: After institutional ethical committee approval, 14 adult (21–85 years) patients undergoing surgery and requiring pulmonary artery catheter (PAC) for measuring CO, were included. Postoperatively CO readings were taken simultaneously with thermodilution (TD) via PAC and esCCO, whenever a change in CO was expected due to therapeutic interventions. Both monitoring methods were continued until patients’ discharge from the Intensive Care Unit and observer recording values using TD method was blinded to values measured by esCCO system. Results: Three hundred and one readings were obtained simultaneously from both methods. Correlation and concordance between the two methods was derived using Bland‑Altman analysis. Measured values showed significant correlation between esCCO and TD (r = 0.6, P < 0.001, 95% confidence limits of 0.51-0.68). Mean and (standard deviation) for bias and precision were 0.13 (2.27) L/min and 6.56 (2.19) L/min, respectively. The 95% confidence interval for bias was ‑ 4.32 to 4.58 L/min and for precision 2.27 to10.85 L/min. Conclusions: Although, esCCO is the only true non‑invasive continuous CO monitor available and even though its values change proportionately to TD method (gold standard) with the present degree of error its utility for clinical/therapeutic decision‑making is questionable.

The significance of non invasive cardiac output monitoring system on evaluating circulatory and respiratory function in pig with acute respiratory distress syndrome / 中华危重病急救医学

Objective To investigate the effect of non invasive cardiac output monitoring(NICO)system in pig model with acute respiratory distress syndrome(ARDS),and to provide experimental basis for clinical application. Methods Eleven anaesthetized and ventilated ARDS male pig models were induced by intravenously infusing 0.2 mL/kg oleic acid. Lung recruitment was condocted by pressure control ventilation on pigs with ARDS. The optimal positive end-expiratory pressure(PEEP)was determined by optimal dead space fraction〔the ratio of dead space to tidal volume(VD/VT)〕. Cardiac output(CO)was determined by NICO,the respiratory function was monitored, and the VD/VT,dynamic compliance(Cdyn),oxygenation index(PaO2/FiO2),the volume of alveolar ventilation(Valv) and arterial blood oxygen saturation(SaO2)were recorded before infusing oleic acid,after stabilization of ARDS model and at optimal PEEP level,and the intrapulmonary shunt fraction(Qs/Qt)was calculated. CO was also determined by application of pulse indicated continuous cardiac output(PiCCO),and the linear regression analysis between CO determined by NICO and CO determined by PiCCO was conducted. Results Seven experimental ARDS pigs model were successfully established. The optimal PEEP identified by the lowest VD/VT method was(15.71±1.80)cmH2O (1 cmH2O=0.098 kPa). Compared with before infusing oleic acid,VD/VT and Qs/Qt after stabilization of ARDS model were significantly increased〔VD/VT:(72.29±8.58)% vs.(56.00±11.06)%,Qs/Qt:(21.04±15.05)%vs.(2.00±1.32)%,both P0.05). There was linear correlation between CO determined by NICO and CO determined by PiCCO(r2=0.925,P<0.001). Conclusions NICO technique provides a useful and accurate non invasive estimation of CO and respiratory function.VD/VT provided by NICO can titrate the optimal PEEP in patients with ARDS.

The Hemodynamic Effects of a Tourniquet Application during Knee Surgery in Elderly Patients with Hypertension / 대한마취과학회지

BACKGROUND: The hemodynamic and metabolic effects of tourniquet application undergoing knee surgery with general anesthesia in elderly patients with hypertension have been rarely reported. We evaluated the hemodynamic and metabolic effects in elderly patients compared with young adults. METHODS: Thirty elderly patients (elderly hypertension group, 71.8 +/- 3.9 years) with chronic hypertension undergoing total knee replacement and 30 young adults (normal group, 33.1 +/- 5.1 years) undergoing knee surgery were studied. Mean arterial pressure (MAP), heart rate, cardiac index (CI) by esophageal doppler method, and systemic vascular resistance index (SVRI) were measured before, during, and after tourniquet application. pH, PaO2, PaCO2, Hb and lactate blood concentrations were also measured. RESULTS: MAP increased 25% and 16% in elderly hypertension and normal groups during inflation, respectively (P < 0.05) and returned to basal values after deflation. CI increased to 30% higher than basal values in both groups after deflation (P < 0.05). SVRI decreased 31% and 19% in elderly hypertension and normal groups after deflation, respectively (P < 0.05). After deflation, PaCO2 and lactate increased (P < 0.05). CONCLUSIONS: Elderly patients with hypertension have the significant hemodynamic changes during and after tourniquet application than before, however, there are no differences compared to normal group. These elderly patients should be needed the active hemodynamic monitoring due to the lower compensatory ability.

Hemodynamic and Metabolic Changes Induced by Tourniquet Release during Both Total Knee Replacement Arthroplasty / 대한마취과학회지

BACKGROUND: A tourniquet is usually used for total knee replacement arthroplasty (TKR) to provide a bloodless surgical field. However, hemodynamic and metabolic changes result from the ischemia after application of a tourniquet. Moreover, the hemodynamic and metabolic effects of tourniquet application during both TKR under general anesthesia have been rarely reported. METHODS: Fifteen patients undergoing both TKR were studied during general anesthesia. Hemodynamic and metabolic parameters were measured before inflating the tourniquet, just before release of the tourniquet and 3, 6, 15 min after tourniquet release. Stroke volume (SV), cardiac index (CI), systemic vascular resistance (SVR) and end-tidal CO2 (ETCO2) were measured using a non-invasive cardiac output monitor. RESULTS: Mean arterial pressure (MAP) decreased after tourniquet release, but was not different from MAP before tourniquet inflation. After tourniquet release, central venous pressure, SVR, arterial pH, bicarbonate and calcium decreased significantly (P <0.05), and heart rate, CI, ETCO2, PaCO2 and potassium increased significantly (P <0.05). But, the hemodynamic and metabolic changes after tourniquet release in the subsequent TKR were not affected by those after tourniquet release in the antecedent TKR. CONCLUSIONS: During both TKR, although there was no difference in the hemodynamic and metabolic changes after tourniquet release between the antecedent and the subsequent TKR, there were significant hemodynamic and metabolic changes after tourniquet release. These findings indicate the need for more active hemodynamic and metabolic monitoring in patients with a compromised cardiopulmonary function.

The Effect of the Lithotomy-Trendelenburg Position on Respiratory and Hemodynamic Changes during General Anesthesia / 대한마취과학회지

BACKGROUND: The effects of Trendelenburg positions used to expose the surgical field may induce intraoperative hemodynamic and respiratory changes that complicate anesthetic management. This study was performed to evaluate the effects of the lithotomy-Trendelenburg position on respiratory and hemodynamic changes with time passage during general anesthesia. METHODS: Twenty patients undergoing anorectal surgery with general anesthesia were studied. Hemodynamic and respiratory parameters were measured before the lithotomy-Trendelenburg position (L) and 3 min (LT3), 6 min (LT6), 12 min (LT12), 30 min (LT30) and 60 min (LT60) after the 30 degree Trendelenburg position. The cardiac index (CI), stroke volume (SV), systemic vascular resistance (SVR), airway resistance (Raw) and dynamic compliance (Cdyn) were measured by a non-invasive cardiac output monitor. RESULTS: Central venous pressure and peak inspiratory pressure were markedly increased from the lithotomy to the lithotomy-Trendelenburg position. Heart rate was slightly increased while SV, CI, SVR and MAP were decreased. No significant changes of the SV or CI were observed during surgery. The Cdyn was significantly decreased. CONCLUSIONS: The steep lithotomy-Trendelenburg position induces moderate adverse hemodynamic and respiratory effects in healthy patients. These findings indicate the need for more active hemodynamic and respiratory monitoring in patients with a compromised cardiopulmonary function.