Biomedical subjects

L A Otto

Publications and source records attributed to L A Otto.

4 recordsLinked to original sources

PubMed1994

Evaluation of ST segment elevation criteria for the prehospital electrocardiographic diagnosis fo acute myocardial infarction.

STUDY OBJECTIVE: To determine retrospectively the diagnostic accuracy of various ECG ST segment elevation criteria for the prehospital ECG diagnosis of acute myocardial infarction. DESIGN AND SETTING: During a six-month period, paramedics acquired prehospital 12-lead ECGs on adult chest pain patients. Investigators interpreted ECGs independently, retrospectively, and blinded to patient outcome. ECGs were classified as meeting or not meeting the six ST segment elevation criteria regardless of ECG morphology if the criteria were present in two or more anatomically contiguous leads: 1 mm or more ST segment elevation; 2 mm or more ST segment elevation; 1 mm or more ST segment elevation in the limb leads or 2 mm or more ST segment elevation in the precordial leads; and the first three criteria with the simultaneous presence of reciprocal changes. ECGs that did not meet any ST segment elevation criteria were classified as normal, nonspecific ST/T wave changes, abnormal but not ischemic, and ischemic. Hospital charts were reviewed for final cardiac diagnosis. TYPE OF PARTICIPANT: Four hundred twenty-eight stable adult prehospital chest pain patients in whom paramedics acquired prehospital 12-lead ECGs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of the 428 cases, 123 (29%) met 1 mm or more ST segment elevation criteria. Sixty-three (51%) of these 123 patients did not have myocardial infarctions. ECG characteristics most frequently associated with these non-myocardial infarction ECGs were left bundle branch block (21%) and left ventricular hypertrophy (33%). The three criteria that required the presence of reciprocal changes had the highest positive predictive values (93% to 95%), with sensitivities ranging from 20% to 33%. The criteria of 1 mm or more ST segment elevation with the simultaneous presence of reciprocal changes had a positive predictive value of 94% and included 18 of the 21 (86%) myocardial infarction patients who had ST segment elevation and received thrombolytic therapy within five hours after hospital arrival. Of the 428 cases, 305 (71%) did not meet any ST segment elevation criteria and had a sensitivity of 81% and a negative predictive value of 49% for the absence of acute myocardial infarction. CONCLUSION: Fifty-one percent of patients whose prehospital 12-lead ECG met 1 mm or more ST segment elevation criteria had non-myocardial infarction diagnoses. ST segment elevation alone lacks the positive predictive value necessary for reliable prehospital myocardial infarction diagnosis. Inclusion of reciprocal changes in prehospital ECG myocardial infarction criteria improved the positive predictive value to more than 90% and included a significant majority (62% to 86%) of acute myocardial infarction patients with ST segment elevation who received thrombolytic therapy within five hours after hospital arrival. ST segment elevation criteria that include reciprocal changes identify patients who stand to benefit most from early interventional strategies.

Adult↗

PubMed1979

Nonfermentative bacilli: evaluation of three systems for identification.

Three systems for the identification of nonfermentative bacilli were evaluated for their rapidity and accuracy of identification of 217 strains. Two of the systems, API 20E (API) and Oxi/Ferm tube (OxiF), are available as kits; the oxidative attack (OA) system is not commerically available. The overall accuracies of the OA, API, and OxiF systems were 91, 69, and 50%, respectively. Identification within 48 h was achieved for 98% of the strains by OA, for 50% by API, and for 18% by OxiF. Most of the organisms that were either misidentified or not identified by API and OxiF were those nonfermentative bacilli which are relatively more fastidious or rarely encountered or both. All three systems accurately identified nonfermentative bacilli commonly isolated at Olive View Medical Center, namely, Pseudomonas aeruginosa, Acinetobacter anitratus, Pseudomonas maltophilia, Acinetobacter lwoffi, saccharolytic flavobacteria (CDC IIb), moraxellae, Pseudomonas fluorescens, and Pseudomonas putida. The OA system identified 100% of the above organisms correctly, API identified 99.4%, and OxiF identified 99.3%. Since these organisms comprise 92% of the total number of nonfermentative bacilli isolated at Olive View Medical Center, we conclude that both API and OxiF may be useful alternatives to conventional methods, based on accuracy of identification alone. These two systems were considered substantially inferior to the OA system when both accuracy and rapidity of identification were taken into account.

Bacteria↗

PubMed1978

Pseudomonas vesicularis from cervical specimens.

Biochemical characteristics and antibiotic susceptibilities of five strains of Pseudomonas vesicularis isolated from cervical cultures are reported. The organisms were recovered from Thayer-Martin medium, which, because of its inhibitory properties, restricts over-growth by most other species. Our findings agree with those of Kaltenbach and associates (J. Clin. Microbiol., 1:339--344, 1975) on the importance of esculin hydrolysis, maltose oxidation, and pigmentation in the identification of P. vesicularis. Comparative carbohydrate oxidation studies showed agreement in three of four methods (oxidative attack, buffered single substrate, King oxidative/fermentative medium). No oxidation of carbohydrates was observed in commercial oxidative/fermentative medium. In addition to biochemical characteristics, antibiograms can be useful auxiliary aids in the identification of P. vesicularis and in its differentiation from P. diminuta, a closely related species.

Anti-Bacterial Agents↗

PubMed1976

Rapid method for identification of gram-negative, nonfermentative bacilli.

A rapid system (OA), based on oxidative attack of substrates, was developed for identification of gram-negative, nonfermentative bacillia (NFB). One hundred and twelve strains of NFB from 25 species (representing the genera Pseudomonas, Alcaligenes, Acinetobacter, Bordetella, Flavobacterium, Moraxella, and Xanthomonas) were assayed by OA, buffered single substrate, and oxidative/fermentative methods. The 38 substrates consisted of salts of organic acids, nitrogen-containing compounds, alcohols, and carbohydrates. Ninety-four percent of the test strains were identified by the OA method in 24 h, and 99% were identifiable in 48 h. Reproducibility was 99%. Correlation with buffered single substrate was 98% (all substrates) and 90% with the oxidative/fermentative method (carbohydrates only). Biochemical profiles of all strains are presented, as well as tables showing the most useful tests for identification.

Acinetobacter↗