Contrast medium prevention

Barrett BJ, Parfrey PS. Clinical practice, Preventing nephropathy induced by contrast medium, N Engl J Med 2006 354 379-386. 

The following issues, including the etiology, remain to be clarified (a) the pathogenesis of ALPE, (b) the prevention of relapse, and future exercise guidance, (c) why delayed CT shows patchy contrast enhancement even in the recovery phase, (d) whether or not patchy renal vasoconstriction persists for 1-2 weeks, (e) why a contrast medium is present in the kidney for 72 h maximum, (f) the association between ALPE and disorders of type II muscle fibers, (g) the reasons for the less marked increases in serum myoglobin and creatine phosphokinase (CPK), and (h) why ALPE frequently develops in patients with renal hypouricemia. 

Table 3 European Society of Urogenital Radiology (ESUR) Guidelines on prevention of generalized contrast medium reactions in adults...

The Contrast Media Safety Committee of the European Society of Urogenital Radiology (ESUR) has produced useful guidelines on dialysis and the intravascular use of contrast media (Table 4) and has reviewed the literature on this subject (187). In addition, they have produced guidelines on the prevention of contrast medium-induced renal damage (Table 5) following a consensus of experts in this field and of members and fellows of the society (188). 

A study from Germany has shown that the antioxidant acetylcysteine plus intravenous saline 0.45% prevented the reduction in renal function induced by contrast agents (190). The authors prospectively studied 83 patients with chronic renal impairment (creatinine clearance under 50 ml/minute). The patients took oral acetylcysteine 600 mg bd for 1 day before and 1 day after the contrast medium. Saline 0.45% was given intravenously at a rate of 1 ml/kg/hour for 12 hours before and 12 hours after 75 ml of iopromide (iodine 300 mg/ml) intravenously. All the patients were encouraged to drink if they were thirsty. A matched control group received placebo and saline. The mean serum creatinine in the control group (42 patients, mean age 65 years) rose from a mean of 212-226 pmol/l 48 hours after contrast injection. In those... 

In addition to using a small dose of low-osmolar non-ionic contrast medium and offering hydration, some authors have recommended the use of calcium channel blockers in patients at high risk of contrast nephrotoxicity. However, the effectiveness of this class of drugs in preventing contrast nephrotoxicity has not been consistently... 

A report from Italy has suggested that intravenous saline 0.4% before and after administration of the contrast medium, an infusion of dopamine 3 micrograms/kg/ minute for 24 hours after the contrast medium, intravenous furosemide 80 mg 30 minutes before the contrast medium, or intravenous mannitol (20%) 250 ml 1 horn-before and 1 hour after the contrast medium each prevented the reduction in renal function caused by the nonionic agents iobitridol, ioversol, or iodixanol (193). However, the protocol of the study was not described, and previous studies have shown that dopamine, furosemide, and mannitol do not offer good protection against contrast media-induced nephrotoxicity. On the other hand, volume expansion with intravenous saline has been found to offer some protection (190). 

The protective effects of intravenous hydration alone (0.45% isotonic saline, 1 ml/kg/hour for 12 hours before and 12 hours after contrast administration), fenoldopam (0.1 microgram/kg/minute for 4 hours before and 4 hours after the procedure), and acetylcysteine (600 mg bd 24 for hours before and 24 hours after the procedure) have been compared in preventing contrast nephrotoxicity after intravascular administration of low-osmolar non-ionic contrast medium (199). The incidence of nephrotoxicity was 15% in the hydration group, 16% in the fenoldopam group, and 18% in the acetylcysteine group. AU the groups were comparable and basehne creatinine clearance was about 60 ml/minute in aU the patients who received a similar dose of the contrast medium (1.5 ml/ kg). The authors concluded that fenoldopam and acetylcysteine do not offer extra protection against contrast nephrotoxicity over hydration alone. 

Prior interleukin-2 therapy can induce atypical contrast medium hypersensitivity in the form of toxic recall reactions of various types (SEDA-17, 537), and these cannot be prevented by glucocorticoid premedication (315). 

Golman K, Cederholm C. Contrast medium-induced acute renal failure. Can it be prevented Invest. Radiol. 1990 25(Suppl 1) SI 27-SI 28. 

The excretion of contrast agent by the liver or the kidney is not exclusive when either of these organs is in a dysfunctional or diseased state, heterotopic excretion by the other organ will occur to compensate for the impediment (688,781, 783). In patients with renal failure or advanced renal disease, contrast media may still be used to produce nephrograms (689) if the tubular obstruction prevents the passage of urine along the nephron, back-diffusion of the contrast medium into the interstitial volume will occur (791,793,794). During the pe-... 

Holtz HG, Schmidt J, Ryschich EW, et al. Isovolemic hemodilution with dextran prevents contrast medium-induced impairment of pancreatic microcirculation in necrotizing pancreatitis of the rat. Am J Surg 1995 169 161-166. 

Gerlach AT, Pickworth KK. Contrast medium-induced nephrotoxicity pathophysiology and prevention. Pharmacotherapy 2000 20 540-548. 

The use of pure tap water without the addition of radiopaque substances is a fundamentally different approach to oral and rectal opacification. It is almost impossible to achieve complete filling of the small intestine and certainly not of the large intestine with water,since normal enteral absorption prevents retention of water in the bowel lumen. Water absorption is effectively inhibited by the addition of mannitol. The best effect is achieved with 250 ml mannitol (5%) in 750 ml of water or juice. Administration of negative oral and rectal contrast medium is required only for differentiation of the mucosa and intestinal lumen if adequate intravenous contrast enhancement can be achieved. 

The above-mentioned procedures to contrast urethra and bladder are not consistent within the literature, where most authors do not administer any contrast medium at all but instead instruct the patient to empty the bladder prior to the examination [1,38,46]. The latter is necessary to prevent masking of a rectocele or enterocele by the combination of a full bladder and a cystocele that blocks the entire genital hiatus. 

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