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Volume 4 Supplement 4

2nd International Symposium on the Pathophysiology of Cardiopulmonary Bypass. Neurological complications after surgery

  • Meeting abstract
  • Open Access

The effect of continuous treatment of the NO liberator sodium nitroprusside on the serum kinetics of the brain marker protein S-100 in infants and children undergoing corrective cardiac surgery with cardiopulmonary bypass

  • 1,
  • 1,
  • 1,
  • 1 and
  • 1
Critical Care20004 (Suppl 4) :P10

  • Published:


  • Nitric Oxide
  • Cardiopulmonary Bypass
  • Sodium Nitroprusside
  • Astroglial Cell
  • Natrium


Measurement of protein S-100 in serum -an astrocytic calcium-binding protein - may provide information on transient astroglial cell activation and disintegration of the related blood-brain barrier (BBB) due to oxidative stress during and after cardiopulmonary bypass (CPB). Conflicting results in vitro have been reported concerning the neuroprotective effect of sodium nitroprusside. We evaluated the effect of continuous treatment of the nitric oxide (NO) liberator sodium nitroprusside on the serum kinetics of protein S-100 in infants and children after corrective cardiac surgery.


Data on 99 children, who were treated with sodium nitroprusside (median age 2.7 months, range 0.03-81.8 months), and on 92 children without treatment (median age 5.0 months, range 0.03-80 months) were retrospectively analyzed. Sodium nitroprusside infusion was started after the induction of anaesthesia and continued during and after termination of CPB with various doses according to the hemodynamic status until the 48th postoperative hour. The serum concentrations of S-100 were analyzed using a commercially available LIA kit (Byk-Sangtec; Dietzenbach-Germany).


There were no significant differences in the bypass data between the nitroprusside-treated and nontreated group (Table 1). In comparison with the prebypass values, a significant similar increase in the concentration of protein S-100 was found 2 h after the termination of CPB in the nitroprusside-treated and nontreated infants, which decreased during the following 48 postoperative hours. However, significantly lower postbypass serum levels of S-100 were found in the sodium nitroprusside-treated group after 24h treatment (P = 0.0005). The prebypass serum concentrations of protein S-100 correlated significantly with bypass time (r = 0.57; P = 0.0001), cross-clamping time (r = 0.50; P = 0.001) and age at operation (r = -0.41; P < 0.0001). No significant relationship was found between the intra- and postoperative doses of natrium nitroprusside and the post-bypass serum levels of S-100.
Table 1

Concentration of protein S-100 (μ g/l)



2 h after bypass

24 h after bypass

48 h after bypass

Nitroprusside-treated (n =99)

0.55 ± 0.36

2.5 ± 2

1.13 ± 1.0

1.0 ± 1.4

Nitroprusside nontreated (n =92)

0.59 ± 0.4

2.8 ± 2

1.99 ± 2.1

1.5 ± 2.3

Mann-Whitney test



P = 0.0005

P = 0.08

Values are expressed as mean ± standard deviation. NS, not significant.


In this study the significant elevation of serum levels of the protein S-100 may indicate increased astroglial cell reactivity and increased S-100 passage to the bloodstream. Longer lasting treatment with the NO liberator sodium nitroprusside seemed to decrease the release of S-100 into the bloodstream and may have delayed protection on the BBB. The neurological significance of such observation, however, should be evaluated in further follow-up studies, including additional neurophysiological and neurodevelopment tests.

Authors’ Affiliations

Deutsches Herzzentrum Berlin, Forschungsinstitut für Molekulare Pharmakologie, Berlin, Germany


© Current Science Ltd 2000