RESUMO
Prolonged hypotension and disseminated intravascular coagulation were seen in a patient after intravasation of barium sulfate contrast medium during a barium enema examination. High endotoxin levels were measured in the contrast material. In vitro, this material induced generation of bradykinin. The clinical features observed may be explained by contact activation of the Hageman factor-dependent pathways caused by the contrast material and/or by circulating endotoxins. Treatment of this rare but severe complication occurring during a barium enema procedure should be directed against the endotoxic shock.
Assuntos
Sulfato de Bário/efeitos adversos , Meios de Contraste/efeitos adversos , Coagulação Intravascular Disseminada/induzido quimicamente , Hipotensão/induzido quimicamente , Idoso , Bradicinina/biossíntese , Endotoxinas/efeitos adversos , Enema/efeitos adversos , Feminino , Humanos , Técnicas In Vitro , Tempo de Tromboplastina Parcial , Fatores de TempoRESUMO
In a rat model, the relationship between the activity of PKA in human PPFs, the changes in arterial BK concentration, and the changes in blood pressure on infusion of PPF was investigated. The rat was chosen as a model because it is reported to be one of the few animals sensitive to human PKA. However, hypotensive reactions after infusion of human PKA-containing PPF were observed only in the presence of a bradykinin-potentiating peptide (BPP9a). A correlation was found between the PKA content of the rapidly infused PPF, the BK generation in the rat, and the fall in arterial blood pressure. In control experiments, infusions of BK provoKed a similar fall in blood pressure at corresponding BK levels. After neutralization of the PKA activity in the PPF with C1-esterase inhibitor, neither a rise in BK level nor a fall in blood pressure was observed on infusion. We conclude therefore that the hypotensive reactions were caused by PKA-mediated generation of BK.
Assuntos
Pressão Sanguínea , Proteínas Sanguíneas/fisiologia , Bradicinina/fisiologia , Fator XII/fisiologia , Hipotensão/fisiopatologia , Fragmentos de Peptídeos/fisiologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Bradicinina/sangue , Modelos Animais de Doenças , Fator XIIa , Feminino , Frequência Cardíaca , Humanos , Ratos , Ratos Endogâmicos , Albumina Sérica/farmacologiaRESUMO
In patients who required volume expansion during extracorporeal circulation, the plasma bradykinin concentration was monitored simultaneously with the mean arterial pressure during infusion of either albumin solution or PPF. The PKA content of the PPF and the albumin solution was 29 and 3 U/L, respectively, measured spectrophotometrically. In six patients receiving 250 ml of PPF, the mean arterial pressure decreased 22% to 54% within 1.5 min after infusion, whereas the plasma bradykinin concentration, measured by radioimmunoassay, increased significantly (p less than 0.0005) during the first minute. In six patients receiving 250 ml of 4% albumin solution, no blood pressure changes were found, and the plasma bradykinin concentration rose only slightly. In vitro, linear correlation (r = 0.94, p less than 0.0005) was observed between the level of PKA of 26 different lots of PPF and the concentrations of bradykinin that were generated in Hageman factor-deficient plasma after incubation with PPF. It is concluded that the hypotensive reactions observed after PPF infusion during extracorporeal circulation are caused by the PKA-induced bradykinin generation.
