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R B Conn

Publications and source records attributed to R B Conn.

13 recordsLinked to original sources
PubMed1992

Effect of an oxygen-enriched solution and multiple dosing of antegrade crystalloid cardioplegic solution on myocardial metabolism during coronary artery bypass graft operations.

The metabolic effect of excessive oxygenation and frequency of administration of antegrade crystalloid cardioplegic solution was assessed in 33 patients undergoing routine coronary artery bypass graft operations. Four patient groups were designed in which the initial aortic root injection was 1000 ml and then 100 ml administered through the vein grafts after completion of each distal anastomosis. The groups were divided as follows: group 1, single dose, normally oxygenated cardioplegic solution infused via the aortic root; group 2, single dose, high oxygen content cardioplegic solution infused via the aortic root; group 3, normally oxygenated cardioplegic solution with additional 250 ml doses via the aortic root every 20 minutes; group 4, high oxygen content cardioplegic solution with additional 250 ml doses via the aortic root every 20 minutes. In all groups myocardial mean septal temperature showed an immediate fall to approximately 11 degrees C with the initial aortic root doses and then a gradual rewarming to approximately 20 degrees C during the crossclamp period (mean 58.6 minutes). Metabolic parameters measured or calculated from the coronary sinus effluent were myocardial oxygen extraction, lactate production, base deficit, inorganic phosphate, glucose, potassium, creatine kinase (total and myocardial band fraction), and catecholamine production. There was no statistically significant difference in any of these determinations between each patient group. Furthermore, myocardial recovery, myocardial performance, and postoperative recovery characteristics were not different. We conclude that single or multidose aortic root crystalloid cardioplegic solution (either oxygen enriched or normally oxygenated) is equally effective in routine coronary artery bypass graft operations when septal temperatures are maintained between 15 degrees and 21 degrees C for a total arrest time of 60 minutes or less. In this study, increasing the volume cardioplegic solution given in multiple doses appeared to offer no significant metabolic or functional advantage in patients without complications who had satisfactory left ventricular function.

Cardioplegic Solutions↗
PubMed1992

Can continuing medical education prepare the current practitioner for the 21st century?

The traditional approach to continuing medical education (CME) will be inadequate to prepare the practicing pathologist for the 21st century. Seminars at regional or national meetings, audiovisual presentations, and similar CME activities are useful to provide updates or to fill in more detailed information in the basic knowledge that all pathologists must acquire during their training. Different, more imaginative approaches will be necessary for the pathologist wishing to acquire the necessary knowledge and skills to utilize the newly developing techniques in pathology, such as flow cytometry, image analysis, and the myriad diagnostic procedures based on molecular biology. Self-directed learning will continue to be an essential approach to CME, and the availability of computer programs, including videodisks, will be increasingly effective. However, it should be acknowledged that self-directed learning has been available since the invention of the printing press. The current pressure for public accountability of medical practitioners clearly indicates that pathologists must accept the reality that CME will not be recognized unless it is provided by an accredited organization and attendance is documented. Pathologists should anticipate institution of recertification procedures involving peer review, which will require documentable CME. This CME will be based on needs assessment, educational objectives, more effective formats, and evaluation of whether CME, in fact, improved the pathologist's effectiveness in practice. The academicians have their sabbaticals to refresh their knowledge and explore new fields; perhaps minisabbaticals should be arranged for both the academicians and the practicing pathologist who cannot be away from his or her responsibilities for 6 months or 1 year. The medical specialty societies are the most suitable groups for organizing these programs, although the actual programs must be provided in the laboratories that actually perform the procedures.

Certification↗
PubMed1978

Clinical laboratories. Profit center, production industry or patient-care resource?

The clinical laboratory is an essential component of the medical-care system. Rapidly increasing expenditures for laboratory services, fraudulent practices and reports of laboratory error are precipitating legislative and regulatory actions that will affect clinical laboratories and how they are used by physicians in caring for their patients. Many problems related to clinical laboratories are due to the rapid introduction of new technologies, to methods of educating medical students and house officers, to the rapidly expanding scientific base of medicine and to economic factors that have subordinated medical and scientific objectives in the laboratory to economic ones. Implementation of existing legislation would settle many of the economic issues, but more effective integration of the clinical laboratory into the patient-care process and better methods for educating medical students in the use of laboratory information are critical tasks for the medical profession.

Accounting↗
PubMed1977

Hypertriglyceridemia in homozygous beta-thalassemia.

A case of hypertriglyceridemia in association with homozygous beta-thalassemia in an 11-month-old female infant is reported. The hypertriglyceridemia proved to be secondary, as it was indicated by clinical features as well as laboratory findings. Attention is called to a possible alteration of lipid metabolism in association with thalassemia major.

Cholesterol↗
PubMed1975

Limits of applicability of the firefly luminescence ATP assay for the detection of bacteria in clinical specimens.

ATP measurement can be used as an indicator of biological mass, and the extreme sensitivity of the firefly ATP assay has led to its use in bacterial detection systems. Clinical specimens present problems not encountered with cultured isolates of known bacterial species. The lower limit of sensitivity for detecting bacteria using the firefly assay is 100,000 bacteria per ml. Non-bacterial ATP, which is probably present in all clinical specimens, produces false-positive results unless it is completely destroyed, and this destruction must be carried out under conditions that do not affect bacterial ATP. A cause of false-negative results is the presence in all urine specimens of unidentified materials that inhibit the luminescent enzymic reaction. These considerations indicate that application of the firefly ATP assay in bacterial detection systems for clinical specimens is feasible only if a preparatory step separates bacteria from interfering materials and from non-bacterial sources of ATP, and concentrates microorganisms to measurable levels. These limitations sharply curtain the applicability in diagnostic microbiology of this exotic chemical reaction.

Adenosine Triphosphate↗