Telemetry outside critical care units: patterns of utilization and influence on management decisions

BACKGROUND: Guidelines for the use of telemetry in hospitalized patients have been proposed by the American College of Cardiology (ACC). However, there have been only a few studies which have investigated the usefulness of these guidelines in clinical practice. HYPOTHESIS: This study assessed the role of telemetry in the decision making process outside the critical care units. METHODS: The observational study, lasting 4 weeks, was conducted in the telemetry unit of a tertiary care teaching hospital and included 61 male patients (age range 40-61 years). They had been directly admitted to the telemetry unit or transferred from a critical care unit and were followed for as long as telemetry was active. Indication for telemetry and the contribution of telemetry to management decisions were assessed by a physician not involved in the care of the patient. RESULTS: Cumulative number of telemetry days was 379 with a mean of 6.2 days per patient. Total number of telemetry events was 297. According to the ACC classification, 14 patients (22.9%) had class I indication, 21 patients (34.4%) had class II indication, and 26 patients (42.6%) had class III indication. Telemetry events were seen in 18.2% of class I patients, in 39.7% of class II patients, and in 42.1% of class III patients. Only 12 telemetry events (4%) resulted in patient management, with none belonging to class III. CONCLUSION: Telemetry findings in patients outside the critical care units are not usually responsible for major therapeutic changes. The value of telemetry in such patients may be overrated.     

Telemetry in health care

This article reviews the use of telemetry in health care. Monitoring of biological signals of medical importance such as the EKG, EEG, and EOG are described. Employment of telemetry in critical medical and surgical environs such as the delivery and operating suites is covered. The enormous importance of telemetry compatible with public communication systems such as voice grade telephone lines for remote medical care is discussed. The article does not enter into strictly engineering systems aspects in any detail; this was not the intent of the author. Nor is there any pretence to a completeness obviously not possible within its confines. It does concentrate on radio (wireless) telemetry transmissions over relatively great distances with freedom of patient movement.     

Use of the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI) to assist with triage of patients with chest pain or other symptoms suggestive of acute cardiac ischemia. A multicenter, controlled clinical trial

BACKGROUND: Approximately 6 million U.S. patients present to emergency departments annually with symptoms suggesting acute cardiac ischemia. Triage decisions for these patients are important but remain difficult. OBJECTIVE: To test whether computerized prediction of the probability of acute ischemia, used with electrocardiography, improves the accuracy of triage decisions. DESIGN: Controlled clinical trial. SETTING: 10 hospital emergency departments in the midwestern, southeastern, and northeastern United States. PATIENTS: 10689 patients with chest pain or other symptoms suggestive of acute cardiac ischemia. INTERVENTION: The probability of acute ischemia predicted by the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI), either automatically printed or not printed on patients' electrocardiograms. MEASUREMENTS: Emergency department triage to a coronary care unit (CCU), telemetry unit, ward, or home. Other measurements were the bed capacity of the CCU relative to that of the telemetry unit; training or supervision status of the triaging physician; and patient diagnoses and outcomes based on clinical, electrocardiographic, and creatine kinase data. RESULTS: For patients without cardiac ischemia, in hospitals with high-capacity CCUs and relatively low-capacity cardiac telemetry units, use of ACI-TIPI was associated with a reduction in CCU admissions from 15% to 12%, a change of -16% (95% CI, -30% to 0%), and an increase in emergency department discharges to home from 49% to 52%, a change of 6% (CI, 0% to 14%; overall P=0.09). Across all hospitals, for patients evaluated by unsupervised residents, use of ACI-TIPI was associated with a reduction in CCU admissions from 14% to 10%, a change of -32% (CI, -55% to 3%); a reduction in telemetry unit admissions from 39% to 31%, a change of -20% (CI, -34% to -2%); and an increase in discharges to home from 45% to 56%, a change of 25% (CI, 8% to 45%; overall P=0.008). Among patients with stable angina, in hospitals with high-capacity CCUs, use of ACI-TIPI was associated with a reduction in CCU admissions from 26% to 13%, a change of -50% (CI, -70% to -17%), and an increase in discharges to home from 20% to 22%, a change of 10% (CI, -29% to 71%; overall P=0.02). At hospitals with high-capacity telemetry units, use of ACI-TIPI was associated with a reduction in telemetry unit admissions from 68% to 59%, a change of -14% (CI, -27% to 1%), and an increase in emergency department discharges to home from 10% to 21%, a change of 100% (CI, 22% to 230%; overall P=0.02). Among patients with acute myocardial infarction or unstable angina, use of ACI-TIPI did not change appropriate admission (96%) to the CCU or telemetry unit at hospitals with high-capacity CCUs or telemetry units. CONCLUSIONS: Use of ACI-TIPI was associated with reduced hospitalization among emergency department patients without acute cardiac ischemia. This result varied as expected according to the CCU and cardiac telemetry unit capacities and physician supervision at individual hospitals. Appropriate admission for unstable angina or acute infarction was not affected. If ACI-TIPI is used widely in the United States, its potential incremental impact may be more than 200000 fewer unnecessary hospitalizations and more than 100000 fewer unnecessary CCU admissions.     

Telemetry system to record force and EMG from cat ankle extensor and tibialis anterior muscles

The purpose of this technical note is to present the design of an eight-channel telemetry system of dimensions and weight small enough to record muscular forces and EMGs simultaneously from gastrocnemius, soleus, plantaris and tibialis anterior muscles of a freely moving cat. All schematics for constructing the telemetry device are shown in detail. Using this system, we were successful in measuring force and EMG data of all four instrumented muscles in freely moving animals. The telemetry system presented here has the advantage over a conventional cable system that recordings may be obtained at any time in the freely moving animal without interference by an experimenter.     

Instrumentation for psychophysiology.

Attempts to reveal why "certain approaches and methods are necessary to obtain valid data that can be described in scientific terms." The approaches are discussed in relation to (a) sensors, (b) telemetry, (c) calibration, and (d) data processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Noise detection during bradycardia pacing with a hybrid nonthoracotomy implantable cardioverter defibrillator system: incidence and clinical significance

The purpose of this study was to prospectively evaluate the incidence of noise detection during bradycardia pacing by an FDA approved hybrid nonthoracotomy ICD system. An illustrative case report which prompted this investigation is provided. Backup bradycardia pacing by tiered therapy cardioverter defibrillators has been useful in preventing postshock bradycardia and occasionally for chronic rate support in bradycardic patients. Unexplained "noise" detected by real-time telemetry has been previously described during bradycardia pacing by a device utilizing automatic gain control for sensing. Eighteen patients were prospectively evaluated for noise detection during ventricular pacing by the ICD. Real-time telemetry was analyzed with each patient: (1) supine, (2) supine with deep inspiration/expiration, (3) supine during Valsalva, and (4) during a change in position from supine to sitting. Analysis of pacing threshold and lead impedance was made in each patient. Eleven of 18 patients had noise detected on real-time telemetry during bradycardia pacing. In 10 patients this was noted during deep inspiration/expiration, in 2 during Valsalva maneuver, and in 5 with position change. There was no evidence in any patient of lead malfunction nor any difference in pacing threshold or lead impedance between patients with noise detected versus those without it. Noise detection by an approved hybrid ICD system is common and may be due to the automatic gain control which maximizes sensitivity during bradycardia pacing. This may lead to clinically significant events, with both suppression of bradycardia pacing and triggering of tachycardia therapy in the absence of ventricular tachyarrhythmias in pacemaker-dependent patients.     

Antihypertensive effects, determined by a telemetry method, of trichloromethiazide and 7-O-ethylfangchinoline, a derivative of tetrandrine, in spontaneously hypertensive rats

1. The antihypertensive effects of 10 mg/kg trichloromethiazide (TCM), 10 mg/kg 7-O-ethylfangchinoline (7-O-EFC) and the combination of these drugs given orally once daily for 2 weeks were investigated by measuring the blood pressure (BP), heart rate (HR) and activity in conscious, freely moving spontaneously hypertensive rats (SHR) fitted with a telemetry device. 2. Clear diurnal rhythms of the HR and activity in synchrony with the light/dark cycle were observed during therapy, whereas the BP rhythm was obscure. 3. Alone, TCM and 7-O-EFC produced slight and insignificant reductions of 24h mean BP, whereas in combination they produced an additive and significant BP reduction, compared with the vehicle-treated controls, from the third day of therapy. The BP reduction induced by the combination of these drugs during the dark phase was more marked than that during the light phase. 4. None of the drug therapies affected the HR and activity diurnal rhythms. 5. The results of the present study demonstrate that the telemetry method is useful for monitoring the antihypertensive effects of drugs in SHR under physiological conditions with minimal stress.     

Technique and instrumentation in physiological psychology.

Attempts to determine (a) the "extent to which various techniques and instrumentation are currently being utilized in physiological psychology" via empirical means, and (b) the "relative significance and potential contributions of various present and future technical developments for an understanding of the physiological bases of behavior" through value judgments. It is suggested that (a) biochemical techniques, (b) microelectrode methods, (c) telemetry, and (d) on-line control use of computers be increasingly employed for more profitable use in future physiological psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于TDLAS的甲烷遥测技术

主要研究了基于TDLAS（可调谐二极管激光吸收光谱）的甲烷气体浓度遥测技术。对其工作原理、系统构成进行分析,重点研究系统光学部分设计,以提高系统的接收效率。实验证明能够达到利用漫反射光线高速高精度检测甲烷气体浓度的目的。     

Patient adaptation to technology: an application of the Roy model to nursing research

Structured interviews were used to explore 75 medical-surgical patients' reactions to intravenous (invasive) and telemetry (noninvasive) attachment. Dependent variables operationalizing constructs of comfort, self-esteem, patient role, and social relationships derived from Roy's four effector modes were organized into 19 adaptation items. It was hypothesized that patients attached to invasive technology would report more stimuli and need for behavioral responses than those attached to noninvasive technology. In keeping with the exploratory nature of the study and use of a new adaptation interview tool, item-by-item analysis was used to test the hypotheses. Most support for the hypotheses occurred when patients were attached to only one invasive device and for less than 3 days. Findings also provide new insights on how technology connections might put patients at risk for coping difficulties.     

Clinical and Applied Research Techniques.

The use of instruments by applied psychologists is universal though seldom recognized. In this section, an attempt has been made to cover several recent advances in the clinical and applied areas of psychology. Topics range from evaluations of biofeedback alpha devices, the use of computers in profile analysis, interviewing, personality assessment, and medical/clinical data processing and simulation to radio telemetry techniques of use to clinical and applied psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-lasting consequences of a social conflict in rats: Behavior during the interaction predicts subsequent changes in daily rhythms of heart rate, temperature, and activity.

This study shows that the long-term consequences of a social conflict in rats do not depend on the physical intensity of the fight in terms of aggression received but, especially, on how the subjects deal with it. Experimental rats were introduced into the cage of an aggressive conspecific for 1 hr, and the effects on daily rhythms of heart rate, body temperature, and activity thereafter were measured by means of telemetry. In some rats, the confrontation caused a strong decrease in the daily rhythm amplitude that lasted up to 3 weeks, whereas other subjects showed only minor changes. The changes in rhythm amplitude did not correlate with the number of attacks received from the territory owner. Contrary to this, the changes showed a clear negative correlation with the aggression of the experimental rats themselves. Subjects fighting back and counterattacking the cage owner subsequently had a smaller reduction in rhythm amplitude. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of telemetric techniques for use in studies of the electrical activity of the brain

A telemetry system has been designed to transmit two channels of wideband activity (0.2 Hz-2.5 KHz) recorded from high-impedance microelectrodes in the brains of free-moving cats. Thus, both unit activity and slow-wave field activity are accessible without disruption of the animals' behavior. In addition, circuitry is described that conditions the receiver signals, that dicriminates valid subcarrier signals from receiver noise and that automatically aborts data output in the absence of discriminable subcarrier. This receiver signal processing circuitry thus assures the fidelity of the decoded subcarrier, greatly facilitates further machine processing of the data and frees the experimenter from having to continuously monitor the receiver signals to subjectively edit out noisy data.     

Telemetric estimation of the descending colon pressure changes on dogs before and after total and selective vagotomy

This experimental study describes the pressure changes of the descending colon before and after total and selective vagotomy combined with Finney's pyloroplasty as estimated by telemetry. The results obtained from the study of 20 dogs show that the motility of the descending colon is extremely reduced after total vagotomy with no change after selective vagotomy.     

Aliphatic and alicyclic diols induce melanogenesis in cultured cells and guinea pig skin

The forces and moments in the shaft of a distal femoral replacement were measured by telemetry for a subject during different activities, and calculations were then made of the forces at the knee. The axial force showed a small peak at heel-strike followed by two main peaks during stance. In level walking, the peak axial force was between 1,487 and 1,718 N (2.2-2.5 BW), the peak shear force was 269-368 N (0.4-0.54 BW) directed anteriorly on the tibia, the peak axial torque was 7 Nm internal, while the patellofemoral force was 466-571 N. The highest axial force was recorded for descending stairs (2.8 BW). Standing on one leg produced 2.4 BW, while lying supine and raising the leg produced 1.7 BW. The data produced may resemble that of a normal subject, and has application to basic joint mechanics, to joint reconstruction, and to total knee replacement design and evaluation.     

Telemetered heart rates of immunosympathectomized and/or adrenal-medullectomized mice during behavioral tasks.

Studied the effects of immunosympathectomy and/or adrenal medullectomy in Swiss-Webster mice in the open field and in each S's home environment. Heart rates (HRs) were monitored via telemetry. Mobility and defecation in the open field were not significantly affected by either immunosympathectomy or adrenal medullectomy. Adrenal medullectomy did affect the relationships between HR and mobility or defecation. The negative correlation between HR and activity of 23 adrenal-intact (AI) Ss became insignificantly positive for 17 adrenal-medullectomized (AM) Ss. Defecating control AI Ss had high HRs, and defecating immunosympathectomized (IS) AM Ss had low HRs. The IS Ss were able to achieve HRs as high as those of controls (>800 bpm) when stressed, but these HRs became significantly lower than those of controls in a short time. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Methods and technique of investigations in the course of sport activities of children (author's transl)

In order to carry out investigations in the course of sport activities of children an efficient telemetering device is essential, which can also be used on children. The Kinderspital Salzburg has developed a telemetry system in cooperation with the Technische Versuchs- und Forschungsanstalt der Technischen Hochschule Wien and the Messerschmitt-B?lkow-Blohm-Werke München. For the first time in this field a Pulse Code Modulation (P.C.M.) System was utilized, implying high accuracy on data transmission and recovery as required for scientific examinations. The children's physical capacity is determined on a bicycle ergometer, and the performance measured in this fashion is then compared with the performance achieved in sport.     

Pacing impedance variability in tined steroid eluting leads

The aim of the study was to investigate pacing impedance (PI) behavior in ambulatory patients. Eighteen atrial and 18 ventricular tined steroid eluting leads with 1.2-mm2 and 5.6-mm2 electrodes were implanted in 20 patients. At 9-27 months after implantation PI was measured automatically by means of additional algorithms downloaded via telemetry links into implanted Thera pulse generators. PI was determined based on the voltage drop on the output capacitor during the 5 V-1 ms pacing impulse, at the programmable sampling rates from 1 second to 30 minutes. The study examined in particular: (1) PI trends and variations associated with different breathing patterns, body postures, provocative maneuvers, bike exercise, and during 24 hours; (2) impact of pacing rate and AV-delay on PI; (3) correlation between PI variability and pacing threshold, lead configuration, absolute PI value, age, gender, disease, and cardiac chamber. The most important findings were: (1) large PI variations of up to 450 omega were observed in properly functioning leads, (2) PI variability exhibited a weak negative correlation with pacing thresholds as if electrode positional stability was not a major factor underlying PI variations, (3) unipolar and bipolar PI variations were equivalent to each other (correlation factor = 0.93) implying that PI was mostly dependent on the circumstances around the lead tip.     

CSP轧机垂振对水平振动影响仿真研究

CSP轧机振动问题是世界范围内轧制领域的重大难题之一。使用快速反应遥测系统对轧机进行了振动综合测试,捕捉到了振动的特征及规律。利用ANSYS的谐响应分析模块及瞬态分析模块对轧机进行了仿真研究,确定了垂振对水平振动的影响,得出了有益的结论。     

Temperature and activity responses to sucrose concentration reductions occur on the 1st but not the 2nd day of concentration shifts, and are blocked by low, constant glucocorticoids.

Previous findings (N. Pecoraro, J. Chou-Green, & M. F. Dallman, 2003; N. Pecoraro & M. F. Dallman, 2005) indicated that unexpected reductions in sucrose concentration in once daily meals result in a febrile response on the 1st, but not the 2nd day of a concentration shift. This study shows that this day-specific fever is blocked by adrenalectomy accompanied by constant low corticosterone replacement. Rats implanted with telemetry probes were adrenalectomized and given low-corticosterone pellets or were sham operated. Food-restricted rats were given 2 rounds of sucrose concentration downshifts, as follows: 32% sucrose (14 days), 4% sucrose (6 days), 32% sucrose (4 days), and 4% sucrose (4 days). Intact rats showed more pronounced anticipation of the sucrose than did rats having low, clamped corticosterone. Only intact rats showed a 4-hr, postshift temperature burst on the 1st, but not the 2nd day of the shift to 4% sucrose, during both rounds of shifting. Increased activity accompanied the fever. These data confirm previous findings, show them to be dependent on high corticosterone, and appear to be related to a host of day-specific alterations in other motor outflows following unexpected downward shifts in palatable sucrose concentrations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)