Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Monitoring”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,369 records · Page 76Linked to original sources
PubMed2007

Diagnostic and prognostic value of ambulatory ECG (Holter) monitoring in patients with coronary heart disease: a review.

Silent ischemia, the most common expression of atherosclerotic heart disease, affects approximately 30-50% of patients during their activities of daily living. The present review provides a comprehensive and practical summary of current knowledge on perioperative myocardial ischemia through MEDLINE searches up to June 2005, using keywords including "silent ischemia," "transient ischemia," and "Holter monitoring." Holter monitoring (i.e., continuous ambulatory ST-segment monitoring) is an effective tool for assessing the frequency and duration of silent transient myocardial ischemia, particularly in patients who are post-acute myocardial infarction (MI), those with acute coronary syndromes (ACS), and in patients in the acute post-operative period. Holter monitoring allows for further risk stratification of patients who have a positive exercise ECG by collecting long-term ECG data on ischemic and arrhythmic events while patients perform routine activities. Both the presence and increased duration of transient ischemia as detected by continuous ST-segment Holter monitoring are associated with increased rates of coronary events and mortality. Holter monitoring may aid in the identification of patients and subgroups of patients with ACS who may derive the greatest benefit from antiplatelet and antithrombotic therapy. Indeed, many ongoing and upcoming trials of pharmacotherapy include ischemia on Holter monitoring as an endpoint.

Electrocardiography, Ambulatory↗
PubMed1988

Role of plasma concentration monitoring in the evaluation of response to antiarrhythmic drugs.

Plasma concentration monitoring of antiarrhythmic agents is valuable, but it is often misused or overemphasized in therapeutic decision-making. There are strict requirements for its appropriate use that are often not met--for both the newer and even the conventional antiarrhythmic drugs. For maximum value, there must be a reliable, accurate relation between the plasma drug concentration and drug action, a relation closer than that between dosage and drug action. The time of sample collection is important--most guidelines are based on "trough" plasma concentrations measured after steady-state equilibrium has been achieved. The use of an accurate, sensitive and specific assay is crucial to the value of plasma concentration monitoring guidelines. However, for agents having active metabolites, monitoring the concentration of only the parent drug can be misleading and limits (but does not necessarily eliminate) the value of plasma concentration monitoring guidelines for these agents. Plasma concentration monitoring of most antiarrhythmic agents is of value for certain specific purposes: to determine compliance to antiarrhythmic therapy, to detect and analyze possible drug interactions, to assess the benefit to risk ratio for increasing the dose of a particular antiarrhythmic agent, to maintain a stable drug effect in the presence of a patient's changing clinical condition and, to a limited extent, to assess the role of an agent in causing an adverse drug reaction. The importance of understanding the assay methods currently in use, as well as how plasma concentration monitoring of individual antiarrhythmic agents is affected by the presence of active metabolites, optical isomers differing in their activity and variations in protein binding, is essential in interpreting data obtained from plasma concentration monitoring.

Anti-Arrhythmia Agents↗
PubMed1993

Prognostic significance of transient myocardial ischemia on ambulatory monitoring after acute myocardial infarction.

The prognostic value of ambulatory ST-segment monitoring after myocardial infarction was prospectively assessed in 203 patients both early (mean 6 days, n = 201) and late (38 days, n = 177). During at least 1 year of follow-up there were 21 cardiac deaths and 44 cardiac events (death, reinfarction or coronary revascularization). ST depression was seen less often during early than late monitoring (29 of 201 [14%] vs 56 of 177 [32%]). Early ST depression was significantly associated with increased mortality (7 of 29 [24%] vs 14 of 172 [8%]) (< 0.05) and increased cardiac events (13 of 29 [45%] vs 30 of 172 [17%]) (p < 0.001) and had independent value after allowing for clinical factors and coronary prognostic indexes (adjusted relative risks 3.40 and 2.70, respectively). ST depression on late monitoring was only associated with increased cardiac events when it was: (1) frequent (e.g., > or = 3 episodes/day [10 of 31 patients, 32% vs 18 of 146, 12%]) (p < 0.01); (2) prolonged (e.g., > or = 20 minutes/day [8 of 25, 32% vs 20 of 152, 13%]) (p < 0.05); or (3) severe (e.g., maximum of > or = 1.5 mm [8 of 28, 29% vs 20 of 149, 13%]) (p < 0.05). Thus, ST depression occurs less frequently during ambulatory monitoring before discharge than during late monitoring, but is a more specific prognostic indicator; however, it is more benign during late monitoring. Ambulatory ST-segment monitoring can be used to predict prognosis in the first year after myocardial infarction, although its relative value as a screening test compared with exercise testing remains to be established.

Electrocardiography, Ambulatory↗
PubMed1982

Implications of self-monitoring for smoking treatment: effects on adherence and session attendance.

The reactive effects of three self-monitoring procedures were evaluated with respect to compliance with the self-monitoring requirements and session attendance. A total of 50 smokers who agreed to participate in a smoking cessation program were randomly assigned to one of five conditions: three self-monitoring conditions and two no self-monitoring control conditions. Results indicate that groups were initially equal on the variables of age, sex, pack year history, estimated rate of consumption, and alveolar carbon monoxide level. Drop-out rates for the no self-monitoring control groups were equal at the second session (10% each) and significantly lower than those of the self-monitoring groups (40%, 40%, and 60%). This significant difference was still present at the sixth treatment session. The implications of increased drop-out rates in smoking cessation programs resulting from self-monitoring are discussed.

Adult↗
PubMed2006

The emotional consequences of social pragmatism: the psychophysiological correlates of self-monitoring.

Self-monitoring refers to the extent to which people regulate their self-presentation by tailoring their behaviors to social situations. To examine the psychophysiological correlates of self-monitoring, we measured heart rate, skin conductance level, and EEG alpha of the frontal and parietal scalp regions during baseline and while anticipating an impromptu speech task. High self-monitors showed lower cortical activity in the frontal and parietal scalp regions than low self-monitors. Furthermore, self-monitoring scores were negatively correlated with skin conductance level when anticipating social threat. Social anxiety and depression did not account for these results. The findings suggest that high self-monitors show lower autonomic and cortical arousal than low self-monitors when anticipating social stress.

Adolescent↗
PubMed2006

Perceptual uniqueness point effects in monitoring internal speech.

Disagreement exists about how speakers monitor their internal speech. Production-based accounts assume that self-monitoring mechanisms exist within the production system, whereas comprehension-based accounts assume that monitoring is achieved through the speech comprehension system. Comprehension-based accounts predict perception-specific effects, like the perceptual uniqueness-point effect, in the monitoring of internal speech. We ran an extensive experiment testing this prediction using internal phoneme monitoring and picture naming tasks. Our results show an effect of the perceptual uniqueness point of a word in internal phoneme monitoring in the absence of such an effect in picture naming. These results support comprehension-based accounts of the monitoring of internal speech.

Adult↗
PubMed2006

Anthracycline-induced cardiotoxicity: comparison of recommendations for monitoring cardiac function during therapy in paediatric oncology trials.

The use of anthracyclines is limited by a dose-dependent cardiotoxicity (A-CT). The aim of this study was to gain insight in the currently available guidelines for monitoring cardiotoxicity during anthracycline therapy in children and in the monitoring recommendations currently used in European paediatric oncology trials. An extensive literature search to identify guidelines was performed and one guideline was identified. Twelve protocols including anthracycline therapy were evaluated. With regard to the minimally required diagnostic tests, parameters and definitions of A-CT most protocols roughly followed the guideline. However, both monitoring schedules and recommendations to prevent further cardiac damage in case A-CT was diagnosed varied widely between protocols and only a minority of the protocols followed the recommendations of the guideline. In conclusion, despite an existing guideline, there is a wide variation in the recommendations for monitoring cardiac function during anthracycline therapy in the currently used European paediatric oncology protocols. A possible explanation could be the lack of rigorous evidence on the most optimal way to monitor cardiac function in children treated with anthracyclines. There is a strong need for evidence from clinical research which can support recommendations for monitoring cardiac function during anthracycline therapy for childhood cancer. In the meantime, it is important to standardize the used cardiac monitoring schedules.

Anthracyclines↗
PubMed2006

Phoneme monitoring in silent naming and perception in adults who stutter.

UNLABELLED: The present study investigated phonological encoding skills in persons who stutter (PWS). Participants were 10 PWS (M=31.8 years, S.D.=5.9) matched for age, gender, and handedness with 12 persons who do not stutter (PNS) (M=24.3 years, S.D.=4.3). The groups were compared in a phoneme monitoring task performed during silent picture naming. The phonological complexity of the target items in the task was varied such that participants monitored either compound words or noun phrases. Performance in this task was compared to phoneme monitoring performed on aurally presented target words to investigate whether any differences observed in silent naming were also evident in perception. Analysis of the response time data, in milliseconds, indicated that PWS were significantly slower as compared to PNS in phoneme monitoring during silent naming; group differences were not obtained in the perception task. The groups were also comparable in the response time to phoneme monitoring within compound words and noun phrases in both silent naming and perception. The findings suggested that PWS were slower in the encoding of segmental, phonological units during silent naming. Furthermore, absence of such differences in perception ruled out a general monitoring deficit in PWS. Findings are interpreted within the context of the psycholinguistic theories of stuttering that postulate phonological encoding and/or monitoring as a causal variable in stuttering. EDUCATIONAL OBJECTIVES: As a result of this activity, the participant should: (1) describe relevant literature on phonological encoding skills in children and adults who stutter, (2) identify paradigms that can be used to investigate phonological processing in PWS, and (3) discuss the role of phonological encoding in speech production.

Adolescent↗
PubMed2006

A practical system for monitoring the outcomes of substance use disorder patients.

Outcomes monitoring and management are receiving mounting attention because of increased emphasis on health care accountability and cost containment. Efficient, practical outcomes monitoring systems (OMSs) are crucial if health care system performance is to be determined and effective/cost-effective treatments are to be identified, but such practical monitoring systems generally are lacking. This article describes the features of such a system for monitoring the care received by, and the substance use and psychosocial outcomes of, patients treated for substance use disorders (SUDs) in the Department of Veterans Affairs (VA). In contrast to a 15-21% follow-up rate achieved by VA SUD program staff under a previously mandated system-wide monitoring system, the monitoring system used in this project achieved a 67% follow-up rate without paying patients for their participation. We provide data on patient characteristics and treatment outcomes, estimate the cost of implementing this type of monitoring system on a broad scale, and provide recommendations for OMSs in other large health care organizations.

Adolescent↗
PubMed2006

Impaired error monitoring contributes to face recognition deficit in schizophrenia patients.

BACKGROUND: It has been proposed that social and cognitive deficits in schizophrenia may result from impaired error monitoring. OBJECTIVE: We tested the hypothesis that among schizophrenia patients, impaired error monitoring contributes to poor face recognition, an important social skill. METHODS: 79 schizophrenia patients and 57 healthy individuals were administered a computerized face recognition test which allowed collection of accuracy and latency performance parameters. Error monitoring was assessed by analyzing reaction times for correct (RTC) and incorrect (RTI) responses. Tests of working memory (WM) and processing speed were also administered. RESULTS: RTI was longer than RTC in patients and controls and did not differ between the groups. RTC was significantly longer in patients than controls. Error monitoring effort, calculated by dividing the difference between RTI and RTC by the sum of RTC and RTI, was significantly smaller in patients than controls. A regression model with face recognition performance as dependent variable showed independent contributions of error monitoring effort, spatial working memory and group (patient/healthy) to test performance and explained 26.1% of the variance. CONCLUSION: Error monitoring function influences face recognition accuracy and is impaired in schizophrenia. Impairments in error monitoring, and spatial WM contribute to face recognition deficits in schizophrenia.

Adult↗
PubMed2001

Measurement characteristics of 2 different self-monitoring tools used in a dietary intervention study.

OBJECTIVE: To examine the measurement characteristics of 2 self-monitoring tools, a food diary and fat scan, used in the dietary intervention of the Women's Health Trial: Feasibility in Minority Populations study. DESIGN: Comparison of fat intake reported on the self-monitoring tools to a criterion measure of fat intake, specifically the mean of a food frequency questionnaire and a 4-day food record. The main outcome measures were differences in fat grams and correlations between each of the self-monitoring tools and the criterion measure. SUBJECTS/SETTING: Six-month postrandomization data from 313 women aged 50 to 79 years who participated in the intervention group of the Women's Health Trial: Feasibility in Minority Populations study. RESULTS: Both self-monitoring tools underestimated fat intake compared to the criterion measure, the food diary by 9 g and the fat scan by 6 g. The self-monitoring instruments were better than chance at detecting a low-fat dietary pattern, however, and did not differ from each other in their ability to do so. APPLICATIONS/CONCLUSIONS: The self-monitoring tools were modestly precise as measures of fat intake, but neither was sufficiently accurate to be reliable as a sole assessment of dietary adherence. Dietetics professionals are encouraged to assess the measurement properties of self-monitoring tools to use them appropriately in supporting dietary changes.

Aged↗
PubMed1997

Usefulness of the addition of heart rate variability to Holter monitoring in predicting in-hospital cardiac events in patients with unstable angina pectoris.

Transient ischemia on Holter monitoring is a major determinant of outcome in unstable angina. In this study we investigated whether analysis of heart rate variability (HRV) may further improve the prognostic yield of Holter monitoring in this clinical setting. We performed 24-hour Holter monitoring in 75 patients with unstable angina (59 men, aged 62 +/- 9 years) within 12 hours of hospital admission. Number and duration of myocardial ischemic episodes, and both time domain and frequency domain HRV measures were obtained from Holter recordings. In-hospital major cardiac events (death or myocardial infarction) occurred in 7 patients (9%). Episodes of ST-segment depression on Holter monitoring were found in 6 of 7 patients (86%) with and in 26 of 68 patients (38%) without events (p <0.05). There were no differences between patients with or without events in both time domain (standard deviation [SD] of all normal RR intervals in the entire 24-hour electrocardiographic recording (SDNN), SD of the mean RR intervals for all 5-minute segments (SDANN-i), mean of SD of all RR intervals for all 5-minute segments (SDNN-i), percentage of differences between adjacent RR intervals >50 ms (pNN50), and square root of the mean squared differences of successive RR intervals) (RMSSD), and frequency domain (ultra low, very low, low, and high frequency) HRV indexes. However, the low-frequency/high-frequency (LF/HF) ratio was significantly higher in patients with cardiac events (2.12 +/- 1.4 vs 1.48 +/- 0.5, p = 0.01). Moreover, when considering only the 32 patients with myocardial ischemic episodes on Holter monitoring, the LF/HF ratio was again higher in the 6 patients with than the 26 patients without major cardiac events (2.45 +/- 1.5 vs 1.31 +/- 0.3, p <0.01). Multivariate logistic regression, including clinical and angiographic variables, showed that transient ischemia on Holter monitoring was the only independent determinant of outcome (odds ratio = 12.2, p = 0.03), with the LF/HF ratio being only slightly over statistical significance (odds ratio for 0.1 increments = 2.8, p = 0.08). Our data confirm that transient ischemia on Holter monitoring is a powerful predictor of cardiac events in unstable angina and indicates that an imbalance in cardiac autonomic tone toward a prevalence of sympathetic activity increases the risk of events in this group of patients.

Aged↗
PubMed1995

Relative importance of electrode placement over number of channels in transient myocardial ischemia detection by Holter monitoring.

To compare the efficacy of 3-channel ambulatory electrocardiographic monitoring (Holter monitoring) with 2-channel Holter monitoring in the detection of transient myocardial ischemia (TMI), channels CM2, CM5, and modified II were studied. Sixty patients with documented coronary artery disease underwent 48-hour Holter monitoring during their normal daily life, followed by exercise stress testing in the laboratory monitored by means of radionuclide ventriculography and standard 12-lead electrocardiography. Analysis revealed that 3-channel Holter monitoring identified 24 patients with a total of 205 TMI episodes and a total ischemic burden of 371.00 mV-min. By itself, CM2 would have detected only 3 patients (13% of the TMI population), 6 TMI episodes (3% of the total TMI episodes), and a 2.4 mV-min ischemic burden (0.7% of the total ischemic burden). Modified II alone would have identified 17 patients (71% of the TMI population), 160 TMI episodes (78% of the total TMI episodes), and 307.24 mV-min of the ischemic burden (82% of the total ischemic burden). The combination of CM5/modified II identified 23 patients (96% of the TMI population), 201 TMI episodes (98% of the total TMI episodes), and 370.44 mV-min of the ischemic burden (98% of the total ischemic burden). These findings suggest that the electrode placement is more important than the absolute number of channels in the detection of TMI by Holter monitoring.

Electrocardiography↗
PubMed1998

Comparison of low-technology and high-technology monitoring of clomiphene citrate ovulation induction.

OBJECTIVE: To determine whether newer monitoring techniques, including urinary detection of the LH surge and vaginal ultrasound, offer an advantage over basal body temperature (BBT) charts alone in achieving pregnancy using clomiphene citrate (CC). DESIGN: Randomized clinical trial. SETTING: Infertility patients in an academic research environment. PATIENT(S): Forty-five women undergoing ovulation induction with CC. INTERVENTION(S): The women were assigned randomly to receive either low- or high-technology ovulation monitoring for a total of 3 ovulatory cycles. Both groups were followed with BBT charts. The high-technology group also was monitored with urinary LH kits and vaginal ultrasound. MAIN OUTCOME MEASURE(S): Cycle fecundity rates for each technique were compared statistically with use of life-table analysis. RESULT(S): Forty-five patients were studied during a total of 134 cycles. The overall cycle fecundity rate was 8%, 10% (8 of 81 cycles) for the low-technology monitoring group and 6% (3 of 53 cycles) for the high-technology monitoring group. These rates were not statistically significant when evaluated by Fisher's exact test (P = .53) or when using life-table analysis and a log-rank test (P = .48). CONCLUSION(S): These data suggest that, for initial attempts at ovulation induction with CC in unselected patients, high-technology monitoring of ovulation offers no increase in fecundity over low-technology monitoring.

Adult↗
PubMed2001

Multivariate and multiscale monitoring of wastewater treatment operation.

In this work extensions to principal component analysis (PCA) for wastewater treatment (WWT) process monitoring are discussed. Conventional PCA has some limitations when used for WWT monitoring. Firstly, PCA assumes that data are stationary, which is normally not the case in WWT monitoring. Secondly, PCA is most suitable for monitoring data that display events in one time-scale. However, in WWT operation. disturbances and events occur in different time-scales. These two limitations make conventional PCA unsuitable for WWT monitoring. The first limitation can be overcome by use of adaptive PCA. In adaptive PCA. the PCA model is continuously updated using an exponential memory function. Variable mean, variance and co-variance are thus adapted to the changing conditions. The second problem can be solved by time-scale decomposition of data prior to analysis. The time-scale decomposition methodology involves wavelets and multiresolution analysis (MRA) in combination with PCA. MRA provides a tool for investigation and monitoring of process measurement at different time-scales by decomposing measurement data into separate frequency bands. Time-scale decomposition increases the sensitivity of the monitoring, which makes it possible to detect small but significant events in data displaying large variations. Moreover, time-scale information is sometimes important in the interpretation of a disturbance to determine its physical cause. Also, by decomposing data, the problem of changing process conditions is partly solved. All the presented methods are illustrated with examples using real WWT process data.

Principal Component Analysis↗
PubMed1998

Accuracy of a portable International Normalization Ratio monitor in outpatients receiving long-term oral anticoagulant therapy: comparison with a laboratory reference standard using clinically relevant criteria for agreement.

The accuracy of a new, portable INR monitor (CoaguChek, Boehringer-Mannheim, Indianapolis, IN) was evaluated by comparing INR results from the portable monitor with results obtained by a laboratory-based method. Dual INR measurements (portable monitor, laboratory) were performed in 163 consecutive outpatients receiving warfarin. Agreement in dual INR measurements was defined based on clinically-relevant expanded and narrow criteria and statistical criteria. Agreement in dual INR measurements also was evaluated as a function of increasing INR. The proportion of dual INR measurements that satisfied the clinically-relevant expanded, and narrow agreement criteria was 90%, and 86%, respectively. Seventy-nine percent of all dual measurements were within 0.5 INR units. The accuracy of the portable monitor was greatest for INR values less than 3.0; above this INR level, the portable monitor underestimated laboratory INR values. The proportion of dual INR measurements within 0.5 INR units for laboratory INR ranges of <2.0, 2.0-3.0, 3.1-4.0, and >4.0 was 98%, 87%, 57%, and 21%, respectively. We conclude that the portable INR monitor achieved a clinically acceptable level of accuracy when compared to the traditional laboratory method and provides a suitable alternative method of monitoring the INR in patients receiving warfarin.

Administration, Oral↗
PubMed2001

Fiber-optic monitoring coupled with confocal microscopy for imaging gene expression in vitro and in vivo.

Detection of fluorescent signals in living cells is a common and powerful technique used to monitor gene expression for multiple biomedical applications. A disadvantage of this approach in vivo, is the limited accessibility for long-term monitoring of the fluorescent signals within organs in living animals. Because of the multiple applications of gene expression monitoring through fluorescent signals, innovative methods for readout are required. We developed a strategy combining gene transfer, fiber-optic or endoscope monitoring, and confocal microscopy for the brain interstitial or cavitary endoscopic visualization of the efficacy of gene delivery and expression in vivo. The approach is also effective in vitro and can be applied to multiple organs in vivo. We show an example of the detection of green fluorescent protein (GFP)-emitted fluorescence following the administration of recombinant GFP-expressing adenovirus or implantation of rat C6 glioblastoma cells infected with the recombinant GFP adenovirus into the rat hippocampus of chronically cannulated rats. The results show that fiber-optic monitoring coupled with confocal microscopy in gene transfer studies is a practical approach that results in a direct, efficient, rapid, and sensitive visualization of fluorescent signals in the brain. This allows for the continuous real-time in vitro or in vivo brain monitoring of gene expression, accurate anatomical localization, multiple experimental manipulations in the same subject or preparation, while no sacrifice of the animal is required to monitor the efficacy of gene transfer and/or expression.

Animals↗
PubMed1999

Evaluation of a real-time blood glucose monitor in children with diabetic ketoacidosis.

Use of a real-time bedside glucose monitor was analyzed during the course of management of diabetic ketoacidosis (DKA) in children. Simultaneous determinations of blood glucose were obtained, using three methods: bedside glucose meter (One Touch II), laboratory glucose analyzer (YSI 2300 STAT), and a real-time bedside glucose monitor (VIA 1-01G Blood Chemistry monitor). Study patients included seventeen patients < 18 years of age admitted to a Pediatric Intensive Care Unit, with blood samples obtained during treatment of DKA by continuous insulin infusion. Four patients did not complete the study. Three experienced temporary technical problems with the monitor, and four required repeat IV placement. Duration of monitor use ranged between 6 and 47 h (mean 24 +/- 4 h). Blood glucose values ranged between 2.6 and 22.5 mmol/l. Overall correlation of blood glucose values were as follows: 0.965, 0.965, 0.973, VIA 1-01G vs. One Touch II, VIA 1-01G vs. YSI 2300 STAT, and One Touch II vs. YSI 2300 STAT, respectively (all P-values < 0.0001). This real-time bedside glucose monitor is accurate at glucose values < 13.8 mmol/l, and reliable for rapid, repetitive analyses. Results indicate that blood glucose values obtained using this real-time monitor are comparable to those using standard methods of measurement, and that this device is clinically applicable for use in management of children with DKA.

Adolescent↗