Haemodynamic instability during hip prothesis removal due to metallosis: An acute chrome/cobalt intoxication? A case report

INTRODUCTION: Metallosis is produced by friction between prothesis pieces, release of metal particles that can enter systemic circulation provoking cobalt or chromium poisoning. No studies have been found in which the mobilization of metal particles causes haemodynamic instability. CASE PRESENTATION: We present the case of an 85 years old male with metallosis, programmed for washing and prothesis extraction (Girldlestone procedure). During pseudotumor drainage and washing, patient presented sudden desaturation and hypotension refractory to volume and phenylephrine administration. Echocardiogram showed overall hypocontractility. Situation was controlled with high inspired oxygen fraction and noradrenaline perfusion. In postoperative period E. coli grew in pseudotumor samples and metal particles could be seen in soft parts as the testicles. Plasma metal concentration showed high levels of chromium, but no chelator treatment was needed. DISCUSSION: Intraoperative hypotension raises several differential diagnoses. Echocardiography was useful to rule out hypovolaemia, pulmonary embolism and cardiac ischaemia. The results of analytical tests are often delayed, especially cultures and plasma metal levels; therefore, if metal poisoning is suspected, supportive treatment should be performed. Chelation and plasmapheresis should be used once the diagnosis is certain and are therefore not useful in the acute phase. CONCLUSION: Intraoperative hemodynamic instability during hip prosthesis explant may be due to bleeding, release of inflammatory or infectious detritus, acute pulmonary thromboembolism, etc. However, the sudden increase of cobalt or chromium ions should be considered as a feasible option in patients with metallosis, despite not presenting previous clinical manifestations of intoxication.