Contrast induced nephropathy?

summary

With the development of modern contrast technology, contrast induced nephropathy (can) has attracted more and more attention. Can refers to the rapid decline of renal function caused by contrast medium. The commonly used contrast agents are usually hypertonic, and the iodine content is as high as 37%. In vivo, the contrast agents are filtered through the glomeruli without being absorbed by the renal tubules. When dehydrated, the concentration of the contrast agents in the kidney increases, which can cause renal damage and acute renal failure. Contrast induced nephropathy? Let's talk about it.

Contrast induced nephropathy?

The serum creatinine of patients receiving contrast medium usually increased within 24 hours, reached the peak at 96 hours, and generally returned to the basic value after 7-10 days. However, it was also reported that renal function decreased progressively within 1-3 weeks, and then returned to the basic value. More than 60% of can patients have oliguria in the early stage, resistance to diuretics and non oliguria.

Most patients with renal function can recover naturally, 10% of them need dialysis treatment, and irreversible renal failure is rare, which needs long-term maintenance of dialysis. Urine examination showed renal tubular epithelial cells, tubular type and various fragments in urine, which was non-specific and not related to the changes of renal function.

Urate crystal is common, occasionally calcium citrate crystal can be seen, a large amount of proteinuria is not common. In most patients with acute tubular necrosis, the urinary sodium excretion was more than 40 mmol / L, and the fractional sodium excretion (FENa) was more than 1%; However, one third of patients with acute renal failure had lower urinary sodium excretion than 20 mmol / L, and the fraction of sodium excretion in patients with oliguria was less than 1%.

matters needing attention

1. In order to avoid or reduce the nephrotoxicity, 20% mannitol and furosemide (furosemide) can be given intravenously on the basis of replenishing the liquid. It can increase the perfusion of renal tissue, reduce the blood viscosity, increase the renal blood flow, strengthen diuresis and promote the excretion of contrast agent. After angiography, patients were encouraged to drink more water, and 5% sodium bicarbonate was used for intravenous drip to alkalize urine and increase urate excretion. 2. For patients with high risk factors or iodine allergy, we should choose non iodine containing contrast agents (such as iopromide) or non-ionic and hypotonic contrast agents to reduce their nephrotoxicity. 3. Active treatment of acute renal failure. Once oliguric acute renal failure occurs, those who are still ineffective after volume expansion and diuresis should be treated with emergency dialysis and treated as acute renal failure.