PubMed HealthSearch

Biomedical subjects

M Lyman

Publications and source records attributed to M Lyman.

17 recordsLinked to original sources

Pneumostasis of experimental air leaks with a new photopolymerized synthetic tissue sealant.

Air leak is a major contributor to increased length of stay and postoperative morbidity following pulmonary surgery. The effectiveness of a new photopolymerized synthetic hydrogel (FocalSeal, Focal, Inc., Lexington, MA) as a sealant for pulmonary air leaks was determined in 10 mongrel dogs (20-35 kg). The animals were anesthetized and underwent left-sided anterolateral thoracotomy with amputation of a 2 x 3-cm segment of the lung apex. Hemostasis was achieved and terminal bronchial openings of 1.5 to 3 mm with vigorous air leaks were identified. After successful injury, the dogs were randomly assigned to sealant (n = 5) or control (n = 5) groups. In treated animals, the sealant was applied by brushing the solution to the cut parenchymal surface and solidified while briefly interrupting ventilation (40-60 seconds) using visible illumination (450-550 nm) from a xenon light source. Controls received no sealant. A single chest tube was maintained at the injury site with a continuous negative pressure of 20 cm of water. All dogs were extubated and allowed to breathe spontaneously under sedation for 24 hours. Chest radiographs were taken postsurgery and presacrifice. All control animals (n = 5) showed persistent vigorous air leak for the duration of the 24-hour observation period. All treated air leaks resolved immediately, and four of five remained sealed throughout the observation period. One leak reappeared after 17 hours due to inadequate sealant thickness over a 3-mm terminal bronchus. Gross evaluation of the treatment group at the end of 24 hours demonstrated intact sealant well adherent to the parenchyma. No evidence of atelectasis or excessive edema was seen, and no sealant-related complications or toxic effects were noted. Radiologically, lungs were fully inflated. Histologic evaluation at 24 hours revealed no evidence of a strong cellular response to the synthetic sealant, and no fibrosis or adhesions were seen, the onset of the healing process was favorable, indicating good biocompatability. In conclusion, this material was found to be an effective means for sealing bronchial and parenchymal air leaks in this model and warrants clinical evaluation.

Animals

Medical language processing with SGML display.

The paper demonstrates several ways that medical language processing can be combined with emerging display technologies to facilitate the extraction of data from free-text patient documents. The techniques allow rapid review via highlighting of the results of processing. Coupling of text markup with further procedures is envisioned.

Asthma

Medical language processing: applications to patient data representation and automatic encoding.

A linguistic approach is presented to develop a representation of patient data. Semantic categories developed for computer processing of narrative clinical reports are shown to be similar to the Medical Concepts used manually to extract data from narrative in Exercises of the Computer-based Patient Record Institute. Clinical statement types composed of these categories are used in the Linguistic String Project (LSP) medical language processing (MLP) system to convert narrative information into relational database tables of patient information. A procedure for mapping the output of the LSP MLP system into SNOMED International codes was developed. Preliminary results and further requirements are discussed.

Abstracting and Indexing

Automatic encoding into SNOMED III: a preliminary investigation.

The Linguistic String Project (LSP) medical language processing (MLP) system converts narrative clinical reports into database tables of patient data. A procedure for mapping the output of the LSP MLP system into SNOMED III codes was developed. Preliminary results and further requirements are discussed.

Abstracting and Indexing

Natural language processing of asthma discharge summaries for the monitoring of patient care.

A technique for monitoring healthcare via the processing of routinely collected narrative documentation is presented. A checklist of important details of asthma management in use in the Glasgow Royal Infirmary (GRI) was translated into SQL queries and applied to a database of 59 GRI discharge summaries analyzed by the New York University Linguistic String Project medical language processor. Tables of retrieved information obtained for each query were compared with the text of the original documents by physician reviewers. Categories (unit = document) were: (1) information present, retrieved correctly; (2) information not present; (3) information present, retrieved with minor or major error; (4) information present, retrieved with minor or major omissions. Category 2 (physician "documentation score") could be used to prioritize manual review and guide feedback to physicians to improve documentation. The semantic structuring and relative completeness of retrieved data suggest their potential use as input to further quality assurance procedures.

Asthma

TEXTINFO: a tool for automatic determination of patient clinical profiles using text analysis.

The clinical data contained in narrative patient documents is made available via grammatical and semantic processing. Retrievals from the resulting relational database tables are matched against a set of clinical descriptors to obtain clinical profiles of the patients in terms of the descriptors present in the documents. Discharge summaries of 57 Dept. of Digestive Surgery patients were processed in this manner. Factor analysis and discriminant analysis procedures were then applied, showing the profiles to be useful for diagnosis definitions (by establishing relations between diagnoses and clinical findings), for diagnosis assessment (by viewing the match between a definition and observed events recorded in a patient text), and potentially for outcome evaluation based on the classification abilities of clinical signs.

Databases, Factual

Gentamicin resistant and sensitive strains of S. aureus. Factors affecting colonization and virulence for infants in a special care nursery.

During an eight month period in 1978, a large number of infants in a special care nursery at Bellevue Hospital, New York City, were found to carry a Staphylococcus aureus which was resistant to gentamicin. The records of 43 newborn infants who were admitted during this period of high prevalence were analyzed retrospectively for factors that might favor acquisition of gentamicin sensitive or resistant strains. It was found that neither sex nor administration of gentamicin or kanamycin played a significant role. Duration of stay was a major determinant of colonization, but there was no significant difference between the median stay of infants colonized with gentamicin sensitive or resistant strains. A life table analysis showed no difference in the rate at which gentamicin sensitive or resistant strains were acquired. As a group, staphylococci were acquired at the same rate as Gram negative rods and less rapidly than S. epidermidis. A review of all nosocomial staphylococcal infections recognized in the unit during 1977 and 1978 did not support a concern that there might be greater risk of serious infections during the months when gentamicin resistant strains of S. aureus were prevalent. Both sensitive and resistant strains appeared to be similar in virulence. Indeed, in this infant population, there were no differences in behavior between gentamicin resistant and sensitive strains of S. aureus.

Carrier State

Natural language processing and the representation of clinical data.

OBJECTIVE: Develop a representation of clinical observations and actions and a method of processing free-text patient documents to facilitate applications such as quality assurance. DESIGN: The Linguistic String Project (LSP) system of New York University utilizes syntactic analysis, augmented by a sublanguage grammar and an information structure that are specific to the clinical narrative, to map free-text documents into a database for querying. MEASUREMENTS: Information precision (I-P) and information recall (I-R) were measured for queries for the presence of 13 asthma-health-care quality assurance criteria in a database generated from 59 discharge letters. RESULTS: I-P, using counts of major errors only, was 95.7% for the 28-letter training set and 98.6% for the 31-letter test set. I-R, using counts of major omissions only, was 93.9% for the training set and 92.5% for the test set.

Diagnosis, Computer-Assisted