Biomedical subjects

M P Larsen

Publications and source records attributed to M P Larsen.

23 records · Page 2Linked to original sources

PubMed1990

Survival rates from out-of-hospital cardiac arrest: recommendations for uniform definitions and data to report.

Survival rates for out-of-hospital cardiac arrest vary widely among locations. We surveyed the definitions used in published studies of out-of-hospital cardiac arrest. Data from 74 studies involving 36 communities showed survival rates ranging from 2% to 44%. There were five different case definitions and 11 different definitions of survivors. The absence of uniform definitions prevents meaningful intersystem comparisons, prohibits explorations of hypotheses about effective interventions, and interferes with the efforts of quality assurance. The most satisfactory numerator for a survival rate appears to be survival to hospital discharge; the most appropriate denominator appears to be witnessed adult cardiac arrest of presumed heart disease etiology, with ventricular fibrillation as the initial identified rhythm. Proposed definitions for the data emergency medical services systems should report as they examine their cardiac arrest survival rates are presented.

Emergency Medical Services↗

PubMed1990

Use of Ulex europaeus agglutinin I (UEAI) to distinguish vascular and "pseudovascular" invasion in transitional cell carcinoma of bladder with lamina propria invasion.

We used Ulex europaeus agglutinin I (UEAI)-immunoperoxidase staining of endothelium to study the accuracy of hematoxylin and eosin (H&E) diagnosis, occurrence, and significance of lymphvascular invasion in transitional cell carcinoma (TCC) of the bladder invading the lamina propria (Stage T1). Original histologic slides from cases (1967 to 1985) with and without vascular invasion were destained and restained with UEAI-immunoperoxidase. Only 5 of 36 biopsies originally diagnosed with lymphvascular invasion had tumor nests within endothelium-lined spaces. The 31 negative biopsies had extensive retraction artifacts lined by connective tissue and fibroblasts around tumor nests. Thirty-five control biopsies remained negative for lymphvascular invasion. Clinical follow-up of the five patients with proven lymphvascular invasion found three without progression of disease 3 to 10 yr postbiopsy, one dead of a local recurrence of TCC 1.67 yr postbiopsy, and one lost to follow-up. Based on this study, we feel that lymphvascular invasion by TCC in Stage T1 tumors is unusual, is frequently misdiagnosed on H&E stain, and does not necessarily portend a poor prognosis.

Carcinoma, Transitional Cell↗

PubMed1989

A community survey of the potential use of thrombolytic agents for acute myocardial infarction.

We surveyed all patients admitted to nine community hospital coronary care units to determine what proportion could be candidates for thrombolytic therapy. During the 12-month study period, there were 4,115 admissions for possible acute myocardial infarction, and 1,076 (26%) had a discharge diagnosis of myocardial infarction. Patients with myocardial infarction had the following characteristics: 60% had ST elevation seen on the first ECG, 17% had ST depression without ST elevation, 75% were less than 75 years old, 75% had no contraindications to thrombolytic therapy, 78% arrived at hospital within six hours of onset of symptoms, and 94% arrived within 24 hours of symptoms. Criteria for administration of thrombolytic therapy can be grouped as restrictive (arrival within six hours of symptoms and ST elevation) or liberal (arrival within 24 hours of symptoms and ST elevation or ST depression). Applying these characteristics, 26% met restrictive criteria for treatment with thrombolytic therapy, and 36% met liberal criteria. Until liberal criteria (therapy up to 24 hours and ST depression) are convincingly shown to be of benefit, we believe clinicians should apply restrictive criteria to potential candidates for thrombolytic therapy.

Aged↗

PubMed1982

PCS-I--a point counting stereology program for cell biology.

PCS-I is a versatile BASIC program designed to collect and process stereological point counting data from electron micrographs of cells. The program can accept the point counts from three sources: (i) a set of user-definable keys programmed as counters; (ii) a numeric pad that enters counts line by line; and (iii) a data tape cartridge. The program calls for all the information needed to solve stereological equations and then helps the user to interpret the suitability of the sample size by drawing error curves. The coefficients of the stereological equations and the output headings can be readily modified to accommodate a new set of experimental parameters, which gives a substantial amount of flexibility to the program. PCS-I is easy to use and offers a practical solution to the problem of data management for biological stereology.

Cell Biology↗

PubMedDate not supplied

Utilization of emergency medical services for symptoms of acute myocardial infarction.

OBJECTIVE: To examine patient characteristics and situational and clinical factors that affect utilization of Emergency Medical Services (EMS) for symptoms of acute myocardial infarction (AMI). DESIGN: Telephone interview of patients hospitalized with suspected AMI. SETTING: Nine hospitals in King County, Washington. PATIENTS: Patients admitted to a coronary or intensive care unit between October 1, 1986, and December 31, 1987, with suspected AMI occurring out of hospital. Spouses of patients who met criteria but died during the hospitalization also participated. OUTCOME MEASURES: Patient demographics, coping strategies, situational factors, prior cardiac history, perceived symptom severity, belief about the nature of condition, and method of transportation. RESULTS: Descriptive statistics showed that although few patients called EMS as a "first thing" in response to symptoms, almost half of all patients called EMS before being hospitalized. Stepwise logistic regression analyses revealed that being older, the belief that one was experiencing a heart attack, the presence of other people (including the spouse), and the lack of physical activity at time of symptom onset, were related to both greater and quicker utilization of EMS. Additionally, education, medical history of angina, and severity of symptoms also were related to utilization of EMS. CONCLUSION: The findings are discussed in a theoretical context, using Leventhal's self-regulatory model to suggest avenues for future research and interventions.

Adaptation, Psychological↗