[Systemic and renal effects of preventing contrast nephrotoxicity with isotonic (0.9%) and hypotonic (0.45%) saline].
OBJECTIVE
Physiological and hypotonic saline solutions have been used interchangeably for preventing contrast media nephrotoxicity. No analysis of the possible differential effects of the two solutions on the milieu interieur or intercompartmental fluid volumes has been performed. Our aim was to study the systemic and renal effects of two types of saline solution regularly used to prevent contrast media nephrotoxicity in patients undergoing coronary angiography.


METHODS
Changes in electrolyte levels and volume distribution were studied in 71 individuals who were randomized to receive either 0.9% isotonic saline (n=36) or 0.45% hypotonic saline (n=35) during the 12 hours before and after contrast injection (2000 mL in each period).


RESULTS
The creatinine level was elevated equally often in the isotonic and hypotonic saline groups. Isotonic saline administration led to reductions in hemoglobin level, hematocrit and plasma albumin level, and to increases in plasma volume, by 12.3% and 10.4% at 24 and 48 hours, respectively. These changes were significant compared with baseline measurements and compared with the group that received hypotonic saline. Neither of the two saline solutions resulted in a change in plasma atrial natriuretic peptide level. Plasma and urine osmolality decreased only with hypotonic saline. The increase in plasma creatinine level was similar with both isotonic and hypotonic saline.


CONCLUSIONS
During standard therapy for preventing contrast media nephrotoxicity, (1) isotonic saline, but not hypotonic saline, increased plasma volume; (2) this increase did not raise the atrial natriuretic peptide level; and (3) no difference in the increase in serum creatinine level was observed between the two saline solutions. These findings provide evidence that 0.45% saline, at a dose suitable for preventing contrast media nephrotoxicity, is associated with a lower risk of volume expansion. This result is important for patients with severely impaired ventricular function.
Marrón
Belén
B
Medical Affairs, Renal Division, Baxter HealthCare, Madrid, España.
Ruiz
Elisa
E
Fernández
Cristina
C
Almeida
Pedro
P
Horcajada
Cristina
C
Navarro
Felipe
F
Caramelo
Carlos
C
D000704:Analysis of Variance; D001810:Blood Volume / Q000502:physiology; D003287:Contrast Media / Q000009:adverse effects*; D017023:Coronary Angiography; D003404:Creatinine / Q000097:blood; D004231:Diuresis / Q000502:physiology; D006400:Hematocrit; D006441:Hemoglobin A / Q000378:metabolism; D006801:Humans; D007038:Hypotonic Solutions / Q000008:administration & dosage; D007552:Isotonic Solutions / Q000008:administration & dosage; D007674:Kidney Diseases / Q000097:blood / Q000139:chemically induced / Q000517:prevention & control*; D011446:Prospective Studies; D012709:Serum Albumin / Q000378:metabolism; D012965:Sodium Chloride / Q000008:administration & dosage* / Q000009:adverse effects; D013599:Systole / Q000502:physiology; D013997:Time Factors
D003287:Contrast Media; D007038:Hypotonic Solutions; D007552:Isotonic Solutions; D012709:Serum Albumin; D012965:Sodium Chloride; D006441:Hemoglobin A; D003404:Creatinine