HEMODIALYSIS AND IOPAMIDOL CLEARANCE AFTER SUBCLAVIAN VENOGRAPHY

RATIONALE AND OBJECTIVES. The dialyzability of iopamidol is unknown and was investigated in patients undergoing long-term hemodialysis for chronic renal failure. METHODS. Ten patients received 30 ml Niopam 300 (Bracco SpA, Milan, Italy) (=18372 mg iopamidol) intravenously into a forearm vein to investigate for occult subclavian stenosis. RESULTS. The elimination half-life of iopamidol before hemodialysis was 69.6 hours and during 4 hours of hemodialysis was 3.5 hours. A single 4-hour hemodialysis cleared 55.7% (95% Ci 51-5-59.8) of the administered dose, while second and third dialyses cleared 25.3% (95% Ci 21.4-29.1) and 10.1% (95% Ci 7.7-12.6) of the administered dose, respectively. Two patients with significant residual urine excretion excreted more than 10% of the administered dose in the urine. For anuric patients, extrarenal clearance provided total body clearance of up to 0.266 L/hr. CONCLUSIONS. Hemodialysis is a rapid and efficient means of clearing iopamidol provided it is performed soon after the contrast study.