RESUMEN
One hundred fifteen ECGs from a hospital service were interpreted by 2 primary care physicians and 2 expert electrocardiographers. When their interpretations were compared with one another and with the Marquette MAC II ECG Interpretation Program, there was great variability. Computer ECG interpretations appeared to benefit primary care physicians most by providing a backup opinion. This second opinion was also of use to expert electrocardiographers. Additional long-term benefits that may be derived from computer systems include improvement of physician interpretation ability, reduction in interpretation time, and standardization of electrocardiographic nomenclature and criteria.
Asunto(s)
Diagnóstico por Computador , Electrocardiografía , Sistemas Especialistas , Hospitales Comunitarios , Médicos de Familia , HumanosAsunto(s)
Síndrome de Inmunodeficiencia Adquirida , Empleo , Industrias , Humanos , Política PúblicaRESUMEN
We studied the effect of bicarbonate and acetate on oxygenation during dialysis in ten male chronic dialysis patients. The dialysis delivery system and dialysate constituents were identical except for the use of either bicarbonate or acetate. We found no hemodynamic differences between the two kinds of dialysis. Blood PO2 fell by a similar amount, but blood PCO2 was higher during bicarbonate dialysis. The blood pH became alkalotic by the second hour of bicarbonate dialysis and remained so throughout the dialysis, whereas blood pH became alkalotic only at the end of acetate dialysis. The P50 increased significantly only during bicarbonate dialysis, but 2.3 DPG concentration did not change. Red cell volume, assessed by the mean corpuscular hemoglobin concentration, was unchanged. Without changes in the red cell volume we cannot explain the observed changes in P50 in the absence of concomitant changes in 2.3 DPG concentration.
Asunto(s)
Bicarbonatos , Hemoglobinas/metabolismo , Oxígeno/sangre , Diálisis Renal/métodos , 2,3-Difosfoglicerato , Acetatos , Adulto , Anciano , Ácidos Difosfoglicéricos/sangre , Humanos , Concentración de Iones de Hidrógeno , Masculino , Persona de Mediana Edad , Oxihemoglobinas/metabolismoRESUMEN
Indications for permanent pacing in the bradyarrhythmias are summarized. In the absence of symptoms, pacing is justified only when Mobitz type II block or complete atrioventricular (AV) block is localized in the bundle-branch system. All other abnormalities of impulse generation or conduction (incomplete AV block of any type, atrial fibrillation with slow ventricular response, or sinus node dysfunction) must be shown to be stable and intrinsic and to cause CNS symptoms or hemodynamic compromise to justify pacing. Isolated intra-Hisian abnormality without failure of AV conduction is benign. Measurement of HV interval does not contribute significant information. Correlation of carotid sinus sensitivity with carotid sinus syncope is poor (5%). Bradyarrhythmia produced by minimal effective doses of an essential drug is a rare indication for pacing and requires special documentation. Inadequate indications, sources of error, and misconceptions are discussed. Generally, it is important to exclude drug effect, transient clinical states, and correctable systemic disease as causes of the abnormality before making a conclusion about pacing.