Talk before you walk. The right wireless handheld allows caregiver to spend more time with patients, less time in transit.
Explore the source record for details and available documents.
Computer Communication Networks↗
SEARCH · Search PubMed
Results for “Computers, Handheld”
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.
Image guidance during abdominal exploration for recurrent colorectal cancer.
BACKGROUND: Real-time intraoperative image guidance has been successfully applied to malignancies of the head, neck and central nervous system. Few attempts have been made to apply this technology to gastrointestinal cancers. Our purpose was to determine if a computer-assisted navigation system could be accurately used at the time of abdominal exploration. METHODS: Fourteen patients with resectable recurrent colorectal cancer underwent computer tomography (CT) imaging of the abdomen and pelvis. The CT images were uploaded to a StealthStation (Medtronic, Inc., Minneapolis, MN), a device that tracks the motion of a handheld probe in the operating field and displays its position, in real time, on the uploaded images. Various anatomic points were utilized to match, or register, the patient to the images in the navigation system. After four or more anatomic points were registered, the accuracy of the registration process was computed by the navigation system and reported as the global error. RESULTS: A total of 23 different anatomic structures were used for registration. The median number of points used for registration per patient was 6.5 (range 5-9). The anatomic sites most commonly used were the anterior superior iliac spines, aortic bifurcation, sacral promontory, symphysis pubis, and iliac artery bifurcation. The median global error was 10.0 mm (range 6.7 mm-27.0 mm). CONCLUSION: Computer-assisted navigation systems can be used to accurately deliver image guidance at the time of abdominal exploration. Future work will be directed at determining the value of this technology in the localization and resection of tumors.
Aged↗
Quantitative densitometric analysis using a commercially available handheld CCD digital camera.
We describe here a novel method that relies on a digital imaging device to perform densitometric quantitation of radiographs in the laboratory setting. Using fluorescent back-illumination and appropriate exposure settings, a commercially available handheld charge-coupled device (CCD) digital camera is used to acquire the image of the radiograph. Following acquisition, the image is downloaded by means of a serial interface to a personal computer. There, it is analyzed to ensure that the series of pixel intensities lie within the linear range and then quantitated using two-dimensional integration with local background substraction. Using a linear dot blot established with serial dilution of 32P and imaging with standard radiographic film, we found that images acquired using the handheld digital camera were comparable to those input with a desktop scanner in transmittance mode. Quantitative densitometric analysis showed similar linear results between the digital camera and the desktop scanner over the 16-fold linear response of the radiographic film, both of which were comparable to phosphor imaging over that limited range. These findings demonstrate that the ever-improving technology of handheld digital imaging should be added to the repertoire of techniques for quantitative densitometry.
Animals↗
Comparison of a digital and a handheld infrared pupillometer for determining scotopic pupil diameter.
To compare a digital infrared pupillometer with a handheld infrared pupillometer for determining scotopic pupil size. Department of Ophthalmology, Johann Wolfgang Goethe-University, Frankfurt am Main, Germany. In 100 eyes of 50 healthy individuals (mean age 38.8 years +/- 10.7 [SD]), the scotopic pupil size was measured with a digital (Procyon) and a handheld (Colvard) infrared pupillometer. After dark adaptation of 1 minute, measurements were performed with both devices by 2 examiners (E1 and E2). Agreement and repeatability were analyzed using a comparison method described by Bland and Altman. The mean scotopic pupil diameter was 5.90 +/- 0.97 mm (range 3.24 to 7.91 mm) with the Procyon and 5.78 +/- 0.98 mm (range 3.00 to 7.30 mm) with the Colvard pupillometer. The mean difference between the 2 devices was -0.01 mm (E1) and -0.24 mm (E2). The limits of agreement ranged from 2.84 (E1) to 3.24 (E2). The coefficients of repeatability were 0.64 (Procyon) and 1.16 (Colvard). The mean difference between E1 and E2 was -0.10 for the Procyon and 0.13 for the Colvard pupillometer. The limits of agreement ranged from 1.28 (Procyon) to 2.32 (Colvard). The digital infrared pupillometer (Procyon) demonstrated better repeatability and agreement in measuring scotopic pupil size than a handheld device (Colvard).
Adult↗
A handheld microcomputer system for control of a jet ventilator.
High-frequency jet ventilation is a relatively new mode of patient ventilation that has seen application in critically ill patients with respiratory failure. Because of the radically different nature of this modality of ventilation, clinicians often are unsure which ventilator parameter settings are appropriate. The authors describe in this paper a handheld microcomputer system to assist in the control of jet ventilators.
Algorithms↗
Functional-Performance Deficits in Volunteers With Functional Ankle Instability.
Context: Although functional-performance tests are dynamic measures used to assess general lower body function, studies investigating these tests for ankle instability have yielded conflicting results.Objective: To determine if a relationship exists between a measure of functional ankle instability and deficits in functional performance.Design: A case-control study correlating subject performance on a set of lower extremity functional-performance tests with a measure of ankle instability.Setting: University athletic training research laboratory.Patients or Other Participants: We recruited 60 participants (43 females, 17 males, age = 22.4 +/- 4.9 years, height = 169.9 +/- 9.7 cm, mass = 72.6 +/- 16.3 kg; 42 injured, 18 uninjured) to participate in the study. Six questions were used to determine if functional ankle instability was present in each participant. A point was added for each yes response to produce an index that represents a continuous variable of functional ankle instability.Main Outcome Measure(s): Four unilateral hopping tests were used in this study: figure-of-8 hop, side hop, up-down hop, and single hop. For the first 3 tests, the total time was recorded with a handheld stopwatch to the nearest 0.01 second; for the single hop-for-distance test, the distance was recorded to the nearest 0.01 m. Correlations were computed with the functional ankle instability index and each of the 4 functional-performance tests.Results: No relationship was revealed between the functional ankle instability index and single hop for distance or up-down hop, with r values of -.008 and .245, respectively. A significant relationship was found between the functional ankle instability index and the side hop (r = .35, P </= .01) and the figure-of-8 hop (r = .31, P </= .02).Conclusions: A positive relationship existed between functional ankle instability and performance deficits on the side hop and figure-of-8 hop. Conversely, a relationship did not exist between functional ankle instability and frontal-plane functional-performance activities.
Journal Article↗
Tool time nurses. As handhelds proliferate, ease of use, logistics and the role of the device in direct patient care are keys to success.
Explore the source record for details and available documents.
Computer Peripherals↗
Development of a rat head exposure system for simulating human exposure to RF fields from handheld wireless telephones.
The aim of this project was to develop an animal exposure system for the biological effect studies of radio frequency fields from handheld wireless telephones, with energy deposition in animal brains comparable to those in humans. The finite-difference time-domain (FDTD) method was initially used to compute specific absorption rate (SAR) in an ellipsoidal rat model exposed with various size loop antennas at different distances from the model. A 3 x 1 cm rectangular loop produced acceptable SAR patterns. A numerical rat model based on CT images was developed by curve-fitting Hounsfield Units of CT image pixels to tissue dielectric properties and densities. To design a loop for operating at high power levels, energy coupling and impedance matching were optimized using capacitively coupled feed lines embedded in a Teflon rod. Sprague Dawley rats were exposed with the 3 x 1 cm loop antennas, tuned to 837 or 1957 MHz for thermographically determined SAR distributions. Point SARs in brains of restrained rats were also determined thermometrically using fiberoptic probes. Calculated and measured SAR patterns and results from the various exposure configurations are in general agreement. The FDTD computed average brain SAR and ratio of head to whole body absorption were 23.8 W/kg/W and 62% at 837 MHz, and 22.6 W/kg/W and 89% at 1957 MHz. The average brain to whole body SAR ratio was 20 to 1 for both frequencies. At 837 MHz, the maximum measured SAR in the restrained rat brains was 51 W/kg/W in the cerebellum and 40 W/kg/W at the top of the cerebrum. An exposure system operating at 837 MHz is ready for in vivo biological effect studies of radio frequency fields from portable cellular telephones. Two-tenths of a watt input power to the loop antenna will produce 10 W/kg maximum SAR, and an estimated 4.8 W/kg average brain SAR in a 300 g medium size rat.
Animals↗
Exposure assessment for power frequency electric and magnetic fields.
Over the past decade considerable data have been collected on electric and magnetic fields in occupational environments. These data have taken the form of area measurements, source characterizations, and personal exposure measurements. Occupational EMF levels are highly variable in space and time. Exposures associated with these fields exhibit similar large variations during a day, between days, and between individuals within a group. The distribution of exposure measures is skewed over several decades with only a few values occurring at the maximum field levels. The skewness of exposure measures implies that large sample sizes may be required for assessments and that multiple statistical descriptors are preferred to describe individual and group exposures. Except for the relatively few occupational settings where high voltage sources are prevalent, electric fields encountered in the workplace are probably similar to residential exposures. Consequently, high electric field exposures are essentially limited to utility environments and occupations. Within the electric utility industry, it is definitely possible to identify occupations with high electric field exposures relative to those of office workers or other groups. The highly exposed utility occupations are linemen, substation operators, and utility electricians. The distribution of electric field exposures in the utility worker population is very skewed even within a given occupation. As with electric fields, magnetic fields in the workplace appear to be comparable with residential levels, unless a clearly defined high-current source is present. Since high-current sources are more prevalent than high-voltage sources, environments with relatively high magnetic field exposures encompass a more diverse set of occupations than do those with high electric fields. Within the electric utility industry, it is possible to identify occupational environments with high magnetic field exposure relative to the office environment. Utility job categories with the highest exposures are generation facility workers, substation operators, utility linemen, and utility electricians. There are also higher exposures among traditional "electrical worker" job categories. Outside the electrical utility industry, potential sources of high occupational magnetic field exposures at ELF are induction furnaces, welding machines, electrical transportation systems, and electrical distribution vaults. However, the use of low power electrical equipment such as small motors in close proximity to workers and possibly for long periods of time could also lead to high exposure situations. Handheld survey instruments are available to perform area measurements of electric and magnetic fields at power frequencies but not aat all frequencies within the ELF range. Sophisticated personal computer-based instruments are available to characterize areas and sources across the entire frequency range.(ABSTRACT TRUNCATED AT 400 WORDS)
Electromagnetic Fields↗
Comparison of two systems of measuring energy expenditure.
BACKGROUND: Health care professionals typically use resting metabolic rate (RMR) via indirect calorimetry to determine a person's energy expenditure. Traditional indirect calorimetry measurements involve an expensive, cumbersome piece of equipment that requires careful calibration. The recent development of a handheld indirect calorimeter makes it easier to measure RMR. The purpose of this study was to compare simultaneous measurements of RMR with handheld and traditional indirect calorimeters. METHODS: Healthy, free-living subjects (n = 50) age 18 years and older were tested simultaneously with both indirect calorimeters. All subjects breathed through the handheld device using a mouthpiece while wearing noseclips to prevent leaks. The handheld indirect calorimetry device was placed inside a canopy. The exhaled gas from the handheld was positioned directly over the inlet to the port delivering gases to the traditional device's mixing chamber. The canopy facilitated the simultaneous collection of all expired gases into the traditional device. During the measurement, oxygen consumption and RMR were continuously recorded on a personal computer. RESULTS: Mean oxygen consumption and RMR did not significantly differ between the two devices, with a mean difference of 0.58 +/- 15.33 mL/min (p = .790) and 4.66 +/- 113.39 kcal/day (p = .773) and an absolute difference of 12.3 +/- 8.99 mL/min and 86.58 +/- 72.32 kcal/day, respectively. Correlation coefficients for oxygen consumption and RMR were 0.945 and 0.941, respectively. CONCLUSIONS: No significant difference was found between the measurements of indirect calorimetry with the MedGem (HealtheTech, Golden, CO) device compared with the DeltaTrac device (Datex-Ohmeda, Madison, WI). These findings suggest that the handheld indirect calorimeter may provide an accurate measure of oxygen consumption and RMR measurements for spontaneously breathing subjects.
Adult↗
Clinical Pearl: the use of the handheld digital camera to capture dermoscopic and microscopic images.
Explore the source record for details and available documents.
Dermatology↗
Teleradiology in orthopaedics.
Teleradiology is a means of electronically transmitting radiographic image files from one location to another. Technologic advances in digital imaging, telecommunications, digital storage, and viewing technologies have made teleradiology readily available and reasonably affordable. The five components of a teleradiology system include: a sending station, a transmission network, a storage device, a viewing station and, a software package. The advantage of teleradiology is the mobility of digital images. In contrast to plain radiographs that only can be seen in one location at a time, multiple persons who are at different locations can view digital images simultaneously. When applied to orthopaedic trauma applications, when the consulting orthopaedist is at a remote location from the patient, teleradiology has been shown to improve diagnostic accuracy, disposition planning of patients from emergency departments or outlying hospitals, and planning of surgical procedures. These systems also improve the comfort level of consulting orthopaedic surgeons and potentially limit the risk of litigation for incorrect diagnosis. The quality, convenience, and effectiveness of teleradiology systems should improve as the technologies continue to mature. Having radiographic images available on handheld devices, such as cell phones, is likely to be a reality in the near future.
Computer Systems↗
A simple computational alternative to analysis of variance formulas for estimating the k-judge reliability.
Formulas requiring the computation of only three standard deviations are presented for computing the interjudge reliability coefficient for any number of judges. These formulas yield coefficients identical to those obtained from a one-way repeated-measures analysis of variance. Even researchers with small handheld calculators can use this simple approach.
Algorithms↗
Summary of measured radiofrequency electric and magnetic fields (10 kHz to 30 GHz) in the general and work environment.
We have plotted data from a number of studies on the range of radiofrequency (RF) field levels associated with a variety of environmental and occupational sources. Field intensity is shown in units of volts/meter (V/m) for electric field strength and amps/meter (A/m) for magnetic field strength. Duty factors, modulation frequencies, and modulation indices are also reported for some sources. This paper is organized into seven sections, each cataloging sources into appropriate RF frequency bands from very-low frequency (VLF) to super-high frequency (SHF), and covers frequencies from 10 kHz to 30 GHz. Sources included in this summary are the following: Coast Guard navigational transmitters, a Navy VLF transmitter, computer visual display terminals (VDTs), induction stoves or range tops, industrial induction and dielectric heaters, radio and television broadcast transmitters, amateur and citizens band (CB) transmitters, medical diathermy and electrosurgical units, mobile and handheld transmitters, cordless and cellular telephones, microwave ovens, microwave terrestrial relay and satellite uplinks, and police, air traffic, and aircraft onboard radars. For the sources included in this summary, the strongest fields are found near industrial induction and dielectric heaters, and close to the radiating elements or transmitter leads of high power antenna systems. Handheld transmitters can produce near fields of about 500 V/m at the antenna. Fields in the general urban environment are principally associated with radio and TV broadcast services and measure about 0.1 V/m root-mean-square (rms). Peak fields from air traffic radars sampled in one urban environment were about 10 V/m, 300 times greater than the rms value of 0.03 V/m when the duty factor associated with antenna rotation and pulsing are factored in.
Electromagnetic Fields↗
Comparing electronic-keypad responses to paper-and-pencil questionnaires in group assessments of alcohol consumption and related attitudes.
Electronic versions of questionnaires have the potential to improve research and interventions in the addictions. Administering questionnaires electronically to groups, however, has proven difficult without a multitude of computers, but gathering data electronically from a group could make for easy assessment and quick feedback. Using a sample of 107 college students, we examined the validity of wireless keypad survey responses by comparing them to traditional paper-and-pencil questionnaires. The two formats led to almost identical responses that did not differ significantly from each other (all effect sizes less than g=.15) and high correlations between formats. The wireless, handheld keypad procedure appears to generate data that are as valid as questionnaire responses and permit rapid feedback to groups, as well as easy, human error-free data entry for analysis.
Adult↗
Development of a low cost, GPS-based upgrade to a standard handheld gamma detector for mapping environmental radioactive contamination.
A low cost extension to a standard handheld radiation monitor was developed, allowing one to perform outdoor georeferenced gamma measurements. It consists of a commercial wireless Bluetooth GPS receiver, a commercial RS-232 to Bluetooth converter combined with a standard Bluetooth enabled pocket personal computer (PPC). The system is intended for use in difficult to access areas, typically for foot campaigns. As the operator walks, a straightforward homemade visual basic program alternately reads GPS position and gamma dose rate into the PPC, creating a data log. This allows a single operator on foot to map between 50 and 200 ha of environmental radiation per day in very rugged areas, depending on the accessibility of the terrain and the detail required. On a test field with known contamination, a spatial precision of about 5-10 m was obtainable. The device was also used to reveal complex contamination patterns in the flooding zones of a radioactively contaminated small river.
Hazardous Substances↗
Student documentation of multiple diagnoses in family practice patients using a handheld student encounter log.
Patient encounter logs may provide an important early opportunity to assess beginning clinical students' attention to and experience with many medical problems. However, there are reasons to doubt the completeness of traditional paper logs. The family practice clerkship at Washington University in St. Louis has tried a series of structured paper and hand held computer logs in search of a format that permits students to completely document their patients' diagnoses. The clerkship introduced a Palm computer log, designed with PumaTech's Satellite forms (R), that uses patient demographics to select a diagnosis entry screen displaying many likely diagnoses as checkboxes. Additional drop lists and combinations of drop lists provide access to less common diagnoses. Students using this log document 2.4 problems per patient on average, and as many as 14 problems in a single patient. Differences between students and preceptors are readily apparent. It is now possible to prepare students to rotate with specific preceptors, and to identify or predict gaps in experience that deserve remedial intervention.
Clinical Clerkship↗
Rapid three-dimensional echocardiography : clinically feasible alternative for precise and accurate measurement of left ventricular volumes.
BACKGROUND: Clinical applicability of conventional ultrasonographic systems using mechanical adapters for 3D echocardiographic imaging has been limited by long acquisition and processing times. We developed a rapid (6-s) acquisition technique that collects apical tomograms using a continuously internally rotating transthoracic transducer. This study was performed to examine the clinical feasibility of rapid-acquisition 3D echocardiography to estimate left ventricular end-diastolic and end-systolic volumes using electron-beam computed tomography as the reference standard. Methods and Results-We collected a series of 6 to 11 apical echocardiographic tomograms, depending on heart rate, in 11 patients. There was good correlation, low variability, and low bias between rapid 3D echocardiography and electron-beam computed tomography for measuring left ventricular end-diastolic volume (r=0.96; standard error of the estimate, 21.34 mL; bias, -4.93 mL) and left ventricular end-systolic volume (r=0.96; standard error of the estimate, 14.78 mL; bias, -6.97 mL). CONCLUSIONS: The rapid-acquisition 3D echocardiography extends the use of a multiplane, internally rotating handheld transducer so that it becomes a precise and clinically feasible tool for assessing left ventricular volumes and function. A rapid-image acquisition time of 6 s would allow repeated image collection during the course of a clinical echocardiographic examination. Additional work must address rapid and automated data processing.
Adult↗