RESUMEN
The content of blood in bone homogenates can be determined quantitatively by estimation of the haemin in the homogenate and in a sample of peripheral blood taken at the same time. Haem is completely split from the haemoglobin molecule by reaction with hydrochloric acid-acetone and converted to haemin, which can be analyzed spectrophotometrically. The blood content can be calculated from the amount of haemin in the homogenate in relation to that of the peripheral blood. This method is useful to determine the real amount of drugs in bone tissue.
Asunto(s)
Sangre , Huesos/análisis , Hemo/análogos & derivados , Hemina/análisis , Preparaciones Farmacéuticas/análisis , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/metabolismo , Espectrofotometría/métodosRESUMEN
Six patients, five of whom had normal and one impaired renal function, and all suffering from purulent arthritis caused by cephalosporin-sensitive germs, were given a seven-day course of 8 g cephacetrile daily. On the first day, 6 g were administered by continuous intravenous infusion at the rate of 500 mg/h, followed by 2 g over a further 45 min. On days 2 to 7, the patients received 2 short infusions of 4 g each at an interval of 12 h. In four patients with normal renal function, serum half-life ranged from 0.8 to 1.4 h, serum levels during continuous infusion from 19 to 31 microgram/ml, and total clearances from 265 to 434 ml/min. In one patients, these values were 1.6 h, 70 microgram/ml and 131 ml/min respectively (small volume of distribution). The concentrations in the synovial fluid varied from 2 to 29 mcirogram/ml; they were generally lower than the serum levels, but clearly exceeded the minimum inhibitory concentrations for germs commonly present in purulent arthritis. In five patients, the synovial fluid became germ-free and the arthritis was clinically cured. In the case presenting with renal insufficiency, the serum half-life was 5.8 h. During continuous administration, a steady state was not attained; peak serum levels amo9nted to 75 microgram/ml and the total clearance to 61 ml/min. The cephacetrile concentrations in the synovial fluid were very high (26 and 67 microgram/ml). In this case, in which the renal insufficiency associated with mycosis fungoides was present before the treatment, renal function deteriorated futher during treatment while the arthritis improved.