The purpose of this study is to compare prospectively the role of transthoracic fine needle aspiration lung biopsy (TFNAB), bronchoscope, sputum cytology in the diagnosis of lung tumors and evaluate the method of small lesion in basing only on chest radiography. We performed 120 TFNAB on 102 in patients with mass lesion visible on chest radiography. The needle of 21 gauge was used. 86 patients with lung cancer, 58 had rigid bronchoscope, 66 had 1 sputum cytological exam, 60 had 2 sputum cytological exams. TFNAB had a highest sensitivity (84.4% for the first time) with a rate of correct cytological typing in 76.7% of cases suffering from lung cancer. It was complicated with pneumothorax in 4 cases (3.3%), hemoptysis in 4 cases with small lesions, two rules in aluminum sawed at interval of 5mm were fixed on the chest wall then the chest radiography was taken to determine the site and the distance of puncture for the TFNAB with good success
Lung Neoplasms ; Cardiography, Impedance ; diagnosis

Calculation of cardiac hemodynamic parameters is based on accurate detection of feature points in impedance cardiogram. According to these parameters, doctors can determine heart conditions, so it is very important to accurately detect the feature point of impedance differential signals. This article presents a process in which we used wavelet threshold method to de-noise signals, and then detected the feature points after six layers wavelet decomposition by using bior3. 7. The experimental data were collected from healthy persons in our laboratory and twenty two clinical patients in Chongqing Daping Hospital by using KF_ICG instrument. The results indicated that this method could precisely detect feature points whether it was from healthy people or clinical patients. This helps to achieve the application of noninvasive detection cardiac hemodynamic parameters in clinical treatments by using impedance method.
Cardiography, Impedance ; Electric Impedance ; Heart ; physiology ; Hemodynamics ; Humans ; Wavelet Analysis

The purpose of this study is to investigate changes of the cardiac output and the cardiac muscle contractility during postural gradient changes in man. Subjects consisted of 15 healthy males that they were aged 23-24 years. The Cardiac output and the contractility were calculated using the impedance cardiogram that were recorded by new apparatus developed in Yonsei Medical Center. The impedance cardiogram was recorded in different 7 gradients which were 0degrees, +/-2degrees, +/- 45degrees and +/-90degrees according to the head position, but it was continuously recorded at each gradient. The each postural gradient was changed after supine resting, 15-20 min, and continued in 5 min. Results of this study were following, 1. The cardiac output was decreased at head up posture (+2degrees, +45degrees and +90degrees) because of decreasing stroke volume. But the cardiac output was increased at head down posture (-2degrees, -45degrees and -90degrees) by increasing stroke volume. 2. The cardiac output was significantly changed at +/-45degrees and +/-90degrees after immediately gradient changes, but it was no significant difference at 0 and +/-2degrees postures from that of supine resting state. 3. At +/-45degrees and +/-90degrees, the cardiac muscle contractility was increased, and in head up posture, amounts of change were more larger than in head down posture.
Cardiac Output* ; Cardiography, Impedance ; Electric Impedance ; Head ; Humans ; Male ; Myocardium* ; Posture ; Stroke Volume

Principle of ambulatory cardiac output (CO) measuring technique is introduced in this paper. A lot of experimental studies of the current distribution on the thorax under the condition that the current injection electrodes were adhered to different positions were carried out by using a developed multi-channel impedance mapping system. The static impedance contour maps (Zo-map) and its pulsatile component contour maps (deltaZ-map) under different measuring conditions were analyzed, and the applicability of a two-compartment coaxial cylindrical model using a spot-electrode array instead of the conventional band-electrode array for ambulatory CO measurement, as well as the optimal spot-electrode array, were discussed. Based on the experimental results and the daily use of the ambulatory CO measuring technique, the optimal spot-electrode array meeting the condition of the two-compartment coaxial cylindrical model was determined as that a pair of spot-electrodes for current injection was located on the positions behind the ears and on the right lower abdomen, and a pair of spot-electrodes for voltage pick-up places on the medial portion at the level of clavicle and on the portion above the xiphisternum.
Cardiac Output ; physiology ; Cardiography, Impedance ; methods ; Electric Impedance ; Electrodes ; Equipment Design ; Humans

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

The current emphasis on the acquisition of physiological data by noninvasive means for mass medical screening and patient monitoring has increased interest in the use of electrical impedance for the measurement of physiological events. The technique has gained some degree of acceptance for monitoring respiration (Baker and Geddes, 1970), and much interest has been displayed recently in use of the technique to measure cardiac output including studies by Kubicek et al. (1966) Judy et al. (1969), and Mohapatra (1981). Other applications using the impedance technique include thoracic fluid accumulation, peripheral blood flow, cerebral blood flow, muscle contraction, eye movement, and uterine contraction, etc. The purpose of this article is to introduce the various impedance techniques for the measurement of physiological variables.
Cardiography, Impedance ; Cerebrovascular Circulation ; Extremities/blood supply ; Female ; Human ; *Plethysmography, Impedance ; Regional Blood Flow ; Respiration ; Uterine Contraction

BACKGROUND: Impedance Cardiography is a noninvasive and simple method of cardiac output determination. The purpose of this study was to compare an impedance device with the thermodilution method during the intraoperative period in patients undergoing open heart surgery. METHODS: The study was undertaken in 12 patients undergoing elective open heart surgery without a shunt. When abnormal impedance signals were obtained, the patients were not included in the analysis. Stroke volume was calculated according to the formula of Bernstein. Cardiac output was measured simultaneously by the impedance cardiograph and thermodilution method. We obtained 41-paired measurements during the surgical procedure. The method described by Bland and Altman and linear regression analysis were used for comparison. RESULTS: The correlation coefficient between the two methods was r = 0.36 (P<0.05). Bias and precision analysis between the two techniques showed a mean difference between techniques of 0.80 L/min and a SD of the differences of 1.71 L/min (95% level of agreement 4.21 L/min to -2.62 L/min). Trending analysis showed the impedance cardiogram to inaccurately track the direction of thermodilution CO changes and to underestimate their magnitude (r = 0.57, intercept -3.29, slope 1.27). CONCLUSIONS: This study reveals clinically significant errors in impedance CO measurements. These inaccuracies may be related to the intraoperative environment and abnormal cardiovascular function. Further investigation of such techniques to improve the performance of the impedance cardiogram in the intraoperative setting is warranted.
Bias (Epidemiology) ; Cardiac Output* ; Cardiography, Impedance* ; Electric Impedance* ; Heart* ; Humans ; Intraoperative Period ; Linear Models ; Stroke Volume ; Thermodilution* ; Thoracic Surgery*

PURPOSE: While the use of coupling material (CM) during defibrillation is known to decrease transthoracic impedance more so than other materials elsewhere, the situation in Korea is unclear. The study assessed the use of paddleskin CM during defibrillation in South Korean emergency institutes (EIs) and measured the impedances. METHODS: From October 15 to October 19, 2009, 112 EIs (all of regional emergency medical centers (EMCs), specialized care centers, and local EMCs) were surveyed. Institute members were queried about their current use of paddleskin CMs during defibrillation. Indications for use were studied by means of a World Wide Web search, descriptions on the CM packaging, and telephone conversations with CM manufacturers and related people. Impedance measurements were recorded from April 13 to August 3, 2009. RESULTS: During defibrillation, 27 different CMs were used in the 108 EIs. Only nine institutes used CMs directly for defibrillation. Impedence of nine CMs could not be measured. The impedance values were 1.69, 1.71, 2.00, and 6.12 ohm for four CMs used for defibrillation; 6.66 and 11.94 ohm for two CMs used for electrodes; 9.71, 9.82, 11.57, 13.68, 13.89, 14.36, 18.31, and 19.66 ohm for eight CMs used for ultrasonography; and 14.05, 17.71, 35.44, and 41.15 ohm for four other CMs. CONCLUSION: More education and public information about the use of CMs for defibrillation are needed.
Academies and Institutes ; Cardiography, Impedance ; Electric Countershock ; Electric Impedance ; Emergencies ; Emergency Service, Hospital ; Internet ; Korea ; Product Packaging ; Republic of Korea ; Telephone

BACKGROUND: The device-guided breathing (DGB) exercise is a non-pharmacological treatment of high blood pressure (BP). Changes in hemodynamic variables after DGB remain to be defined. This study evaluated the hemodynamic effects of DGB in hypertensive patients. METHODS: Fifty-nine hypertensive individuals (male, 56%; age, 44 +/- 10 years) with systolic BP (SBP) in the range of 140 to169 mm Hg and diastolic BP (DBP) < 105 mm Hg were divided into two group: control group (n = 17) vs. DGB group (n = 42) who slowed respiratory rate by using 15 minutes daily DBG (RESPeRATE) over 8 weeks. Heart rate, BP and hemodynamic parameters including cardiac index (CI), thoracic fluid content (TFC), systemic vascular resistance index (SVRI) and total arterial compliance index (TACI) were measured using the ICG Monitor (CardioDynamics) at baseline and study end. RESULTS: Baseline characteristics were not different between the two groups. Office BP (SBP/DBP) was reduced from baseline to end value by 13.2 +/- 11.1/6.9 +/- 7.5 mm Hg in DGB group and 2.2 +/- 6.9/0.5 +/- 6.6 mm Hg in control group (p = 0.001, p = 0.004, respectively). Heart rate, CI, stroke index, and TFC were not changed in both groups. However, the SVRI was lower and the TACI was higher in DGB group than control group (SVRI: 2,728 +/- 599 vs. 3,141 +/- 714 dyne sec m2/cm5, p = 0.002; TACI: 0.845 +/- 0.194 vs. 0.761 +/- 0.184 mm Hg/mL/m2, p = 0.041). CONCLUSIONS: Daily device-guided breathing exercise for 8 weeks lowers the BP mediated by reducing the systemic vascular resistance and increasing the total arterial compliance without changes in heart rate and CI.
Breathing Exercises ; Cardiography, Impedance ; Heart Rate ; Hemodynamics* ; Humans ; Hypertension ; Respiratory Rate ; Vascular Resistance

This paper deals with the clinical application value of Kubicek formula for cardiac stroke volume calculation from the angle of Kubicek model simulation by 3-dimensional finite element method. In the process of computer simulation, we have made a comparison between the result of model simulation, the specific value of Kubicek formula for cardiac stroke volume calculation, and the theoretical value of the prescribed model. The simulation results showed that an approximately linear relationship exists between the impedance change and the blood volume change of the aorta in the model, which has proved that Kubicek formula for cardiac stroke volume calculation has great clinical application value. On the other hand, the new method has opened up a path for studying the basic theory of impedance cardiography.
Algorithms ; Cardiography, Impedance ; methods ; Computer Simulation ; Finite Element Analysis ; Humans ; Models, Cardiovascular ; Stroke Volume