PubMed Health⌕ Search

Biomedical subjects

Y Liaw

Publications and source records attributed to Y Liaw.

11 recordsLinked to original sources
PubMed2001

Occurrence of pulmonary thromboembolism immediately after arthroplasty.

INTRODUCTION: Respiratory complications are common after arthroplasty, with pulmonary thromboembolic disease (PTE) and fat emboli being the most serious. A scintigraphic study was designed to assess the occurrence of both diseases. A prospective tomographic study of perfusion was performed within 24 h of arthroplasty. Details of the detection of fat embolism will be presented elsewhere. METHODS: Patients with previous PTE were excluded. Tomographic lung studies were acquired after 99mTc-macroaggregated albumin injection. Pre- and post-operative arterial blood gases (ABGs) and relevant chest radiography/computed tomography scans were obtained. ABGs were analysed as the difference in alveolar-arterial oxygen gradients, pre- and post-operatively (DA-a). RESULTS: Forty patients were studied (16F, 24M) with a mean age of 71 years (range 36-88 years). Of these, 16 were hip and 24 knee arthroplasties. PTE was detected in 25 of 38 (66%) patients evaluated. The value of DA-a was significantly different between patients with PTE and without PTE (P>0.05). Administration of prophylactic pre-operative low molecular weight heparin makes no difference to the early onset of PTE. CONCLUSION: There is a high incidence of PTE immediately after arthroplasty.

Arthroplasty, Replacement, Hip↗
PubMed2000

A guideline implementation system using handheld computers for office management of asthma: effects on adherence and patient outcomes.

OBJECTIVE: To evaluate effects on the process and outcomes of care brought about by use of a handheld, computer-based system that implements the American Academy of Pediatrics guideline on office management of asthma exacerbations. DESIGN: A before-after trial with randomly selected, office-based Connecticut pediatricians. In both the control and intervention phases, physicians collected data from 10 patient encounters for acute asthma exacerbations. During the intervention phase, the computer provided for structured encounter documentation and offered recommendations based on the guideline of the American Academy of Pediatrics. Patients were contacted by telephone 7 to 14 days after the visit to assess outcomes. RESULTS: Nine study-physicians enrolled 91 patients in the control phase and 74 in the intervention phase. Follow-up information was available for 93% of encounters. Use of the intervention was associated with increased mean frequency/visit of: 1) measurements of peak expiratory flow rate (2.18 vs 1.57) and oxygen saturation (1.12 vs.42), and 2) administration of nebulized beta2-agonists (1.25 vs.71). Visits in the intervention phase lasted longer and fees were higher ($145.61 vs $103.11). There were no significant differences in immediate disposition or subsequent emergency department visits, hospitalizations, missed school, or caretaker's missed work during the 7 days post visit. CONCLUSION: Use of handheld computers that provide guideline-based decision support was associated with increased physician adherence to guideline recommendations; however, visits were prolonged, fees were higher, and no improvement could be demonstrated with regard to the observed intermediate-term patient outcomes. Guideline implementers (and users) should be cautious about putting unvalidated recommendations into practice.

Adolescent↗
PubMed1999

An object-oriented framework for the development of computer-based guideline implementations.

Clinical practice guidelines provide a means of directing medical care towards clinically appropriate and cost-effective interventions. A direct relationship exists between the integration of a guideline into clinical workflow and the effectiveness of the guideline in influencing clinicians' behavior. Computer-based guideline implementations, used at the point-of-care, accomplish this integration. Employing object-oriented technologies, we propose a framework of reusable components for the development of guideline implementation systems. We have identified eight information management services that are common to such systems. Our framework integrates these services and their respective reusable components into clinical workflow to promote the development of comprehensive guideline implementation systems, which should ultimately enhance guideline compliance and the overall quality of care.

Guideline Adherence↗
PubMed1999

User satisfaction and frustration with a handheld, pen-based guideline implementation system for asthma.

OBJECTIVE: To evaluate clinicians' satisfaction and frustrations with the use of a handheld computer system that implements a guideline for management of childhood asthma exacerbations. SETTING: Nine primary-care pediatric practices. DESIGN: Survey component of a randomized, prospective before-after trial. INTERVENTION: Newton MessagePad outfitted with custom software (called "AsthMonitor") that assists in documentation of clinical findings and provides guideline-based recommendations. RESULTS: Overall, 3 users gave strongly positive global ratings while 6 users were neutral. The majority used the documentation functions concurrently with care. Except for recommendations to administer oxygen (which were unsupported by evidence), users found the recommendations appropriate and appreciated the reminders. Seven of 9 participants believed it took more time to document with AsthMonitor. CONCLUSIONS: Handheld computers are acceptable to some office-based practitioners to provide guideline-based advice within the context of the clinical encounter.

Asthma↗
PubMed1998

Conserved T-cell receptor class II major histocompatibility complex contact detected in a T-lymphocyte population.

T-cell receptor (TCR) interacts with an antigenic peptide deeply buried in the major histocompatibility complex (MHC) molecule. How class II MHC is contacted by TCR during antigen recognition remains largely elusive. Here we used a panel of I-Ek mutants to identify two I-Ek residues that were frequently contacted by TCR among a large pool of T cells specific for the same antigen. The restricted TCR interaction with I-Ek was independent of the antigen peptides. We also identified a dominant heteroclitic residue on I-Ek, beta81H, in which mutation led to increased recognition of antigens in individual T-cell clones. Moreover, both the conserved TCR-I-Ek interaction and the heteroclitic TCR-I-Ek recognition were detected in T lymphocytes freshly isolated from mice primed with the specific antigens. The identical TCR-I-Ek interaction in a heterogeneous T-cell population suggested the dominance of invariant TCR-class II MHC interaction.

Animals↗
PubMed1995

Combined fourth and fifth metacarpal fracture and fifth carpometacarpal joint dislocation.

Three cases of hamato-metacarpal fracture-dislocation with fracture of the shaft or base of the fourth metacarpal and dorsal dislocation of the fifth metacarpal are described. In one case this was associated with coronal fracture of the hamate. An oblique radiograph of the hand with the forearm pronated 15 degrees and 45 degrees provided a good view of the extent of the fourth and fifth carpometacarpal injury. Treatment with open reduction and internal fixation achieves good clinical results.

Adult↗
PubMed1994

Haemodilution study in major orthopaedic surgery experience as a technique of blood conservation.

Haemodilution and auto-transfusion were carried out in 103 consecutive patients having major orthopaedic surgery. The records of 99 patients were available for retrospective assessment of this technique. Fifty-six per cent of the patients did not require any homologous blood transfusion. Homologous blood transfusion was given to 44% of the patients, who used up 99 units of blood in their entire hospital stay. There was no morbidity such as transfusion reaction, infection, decrease in platelets or re-operation for bleeding associated with the procedure, although there was one death secondary to myocardial infarction. This technique offered an alternative method to reduce the use of homologous blood transfusion in major orthopaedic operations.

Adolescent↗
PubMed1991

Excimer laser radiation for endarterectomy of experimental atheromas.

Open laser endarterectomy produces a smooth arterial surface with welded distal end points. This report evaluates 308-nm excimer laser radiation for the laser endarterectomy operation. Arteriosclerotic New Zealand white rabbits (N = 15) were studied. A thoraco-abdominal exploration was performed, the aorta was isolated, heparin was administered, and multiple endarterectomies were performed in each rabbit. A line of laser craters was created at the proximal and distal ends of an atheroma. Laser radiation was used to connect the craters to form the proximal and distal end points. The atheromas were dissected from the aorta with laser light and the end points were fused. The aortas were removed for light and electron microscopy and the animals were sacrificed. Excimer radiation was delivered by a 600-microns fiber at 50 mJ/pulse, 120-ns pulses and either 15- or 20-Hz frequency. At 15 Hz excimer laser endarterectomies showed no perforations along the surface or at the end points. The surfaces were smooth but the end points were not welded in place. At 20 Hz, perforations were seen along 7/11 surfaces and at 5/11 end points. Excimer laser endarterectomy is best performed at 15 Hz. The end points, however, cannot be welded with excimer laser radiation.

Animals↗
PubMedDate not supplied

A design model for computer-based guideline implementation based on information management services.

Clinical practice guidelines must be implemented effectively if they are to influence the behavior of clinicians. The authors describe a model for computer-based guideline implementation that identifies eight information management services needed to integrate guideline-based decision support with clinical workflow. Recommendation services determine appropriate activities in specific clinical circumstances. Documentation services involve data capture. Registration services integrate demographic and administrative data. Explanation services enhance the credibility of automated recommendations by providing supportive evidence and rating the quality of evidence. Calculation services measure time intervals, suggest medication dosages, and perform other computational tasks. Communication services employ standards for information transfer and provide data security. Effective presentation services facilitate understanding of complex data, clarify trends, and format written materials (including prescriptions) for patients. Aggregation services associate outcomes with specific guideline interventions. The authors provide examples of the eight services that make up the model from five evidence-based practice parameters developed by the American Academy of Pediatrics.

Decision Support Systems, Clinical↗
PubMedDate not supplied

Computer-based guideline implementation systems: a systematic review of functionality and effectiveness.

In this systematic review, the authors analyze the functionality provided by recent computer-based guideline implementation systems and characterize the effectiveness of the systems. Twenty-five studies published between 1992 and January 1998 were identified. Articles were included if the authors indicated an intent to implement guideline recommendations for clinicians and if the effectiveness of the system was evaluated. Provision of eight information management services and effects on guideline adherence, documentation, user satisfaction, and patient outcome were noted. All systems provided patient-specific recommendations. In 19, recommendations were available concurrently with care. Explanation services were described for nine systems. Nine systems allowed interactive documentation, and 17 produced paper-based output. Communication services were present most often in systems integrated with electronic medical records. Registration, calculation, and aggregation services were infrequently reported. There were 10 controlled trials (9 randomized) and 10 time-series correlational studies. Guideline adherence improved in 14 of 18 systems in which it was measured. Documentation improved in 4 of 4 studies.

Decision Making, Computer-Assisted↗