RESUMEN
Non-ionic dimeric contrast media (CM) are a new class of CM which are iso-osmolar with plasma. The aim of this study was to investigate their effects on systemic and renal haemodynamics. The non-ionic dimeric CM iodixanol and the non-ionic monomeric agent iobitridol (both at a dose of 1,600 mgI/kg) were compared in terms of their effects on systemic blood pressure (BP) and renal blood flow (RBF) in two strains of rats (Wistar and Sprague Dawley). Iodixanol significantly lowered BP in Wistar rats (-33 +/- 9% of baseline, 10 min post-injection, P < 0.001 vs. saline and iobitridol). Iobitridol had virtually no effect on BP. Iobitridol and iodixanol significantly decreased RBF. This effect was more marked following injection of the dimer rather than the monomer (iodixanol: -32 +/- 13% iobitridol: -20 +/- 4 of baseline at 16 min, P < 0.05). For both agents, RBF was still decreased 50 min following injection (iodixanol: -30 +/- 11%, and iobitridol: -20 +/- 5% of baseline). Iodixanol also decreased RBF in Sprague Dawley rats, while BP remained unchanged. This suggests that changes in BP/RBF autoregulation do not account for the renal haemodynamic effects of this agent. When measured 2 h following injection, the iodixanol-induced renal hypoperfusion was still detectable (-29% vs. saline-treated rats), although not significant (P = 0.06). This effect was no longer observed 4 h following injection. Increasing the saline infusion rate (18 mL/h vs. 2 mL/h) during the experiment did not significantly decrease the effects of iodixanol on BP and RBF in Wistar rats. In spite of its iso-osmolality, iodixanol, a non-ionic dimeric CM, depressed RBF and BP significantly more than iobitridol, a monomeric non-ionic agent, in Wistar rats. This effect was long-lasting and was not alleviated by increasing the hydration rate.
Asunto(s)
Medios de Contraste/toxicidad , Hemodinámica/efectos de los fármacos , Yohexol/análogos & derivados , Circulación Renal/efectos de los fármacos , Ácidos Triyodobenzoicos/toxicidad , Animales , Presión Sanguínea/efectos de los fármacos , Agua Corporal/fisiología , Medios de Contraste/administración & dosificación , Hematócrito , Inyecciones Intravenosas , Yohexol/administración & dosificación , Yohexol/toxicidad , Masculino , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Ácidos Triyodobenzoicos/administración & dosificación , Resistencia Vascular/efectos de los fármacosRESUMEN
The aim of the present study was to investigate the effects of four iodinated contrast media on cortical, inner medullary and outer medullary blood flow in the rat kidney by using laser-Doppler flowmetry. The high-osmolar contrast medium diatrizoate did not significantly modify medullary perfusion but moderately decreased the cortical blood flow when injected at a dose of 1600 mg iodine kg(-1). Similar effects were obtained with the low-osmolar contrast media ioxaglate and iobitridol. In contrast, the new iso-osmolar contrast medium iodixanol induced a dose-dependent reduction of perfusion in all regions tested. This effect was accompanied by concomitant hypotension. The reduction of inner medullary and cortical blood flow induced by iodixanol was partially alleviated by heating the solution prior to injection and subsequently reducing its viscosity. In the outer medulla, however, this procedure did not improve blood flow. These results suggest that lowering the viscosity may palliate the harmful effects of iodixanol on the inner medulla and cortex, but may not protect the outer medulla from hypoxic injury.
Asunto(s)
Medios de Contraste/farmacología , Corteza Renal/irrigación sanguínea , Médula Renal/irrigación sanguínea , Circulación Renal/efectos de los fármacos , Ácidos Triyodobenzoicos/farmacología , Animales , Medios de Contraste/química , Medios de Contraste/toxicidad , Diatrizoato/farmacología , Relación Dosis-Respuesta a Droga , Hemodinámica/efectos de los fármacos , Yohexol/análogos & derivados , Yohexol/farmacología , Ácido Yoxáglico/farmacología , Riñón/efectos de los fármacos , Riñón/fisiología , Enfermedades Renales/inducido químicamente , Enfermedades Renales/fisiopatología , Masculino , Ratas , Ratas Endogámicas Lew , Flujo Sanguíneo Regional/efectos de los fármacos , Ácidos Triyodobenzoicos/química , Ácidos Triyodobenzoicos/toxicidad , ViscosidadRESUMEN
The work analyzes findings of 315 autopsies of victims of thermal traumas. Shock and sepsis are considered as causes of death of the burn patients: their share in the structure of lethality, their part in different age groups of the dead, factors contributing to death from shock and sepsis. The use of catheterization was shown to reduce probability of death from shock, but it considerably elevated (in children and middle aged people) risk of their death from sepsis, the early sepsis included.