The perioperative course of C1-esterase-inhibitor: evidence for an early deficiency

Objective

Since the extent of complement-and contact-activation and a low functional index of their main inactivator C1-esterase-inhibitor (C1-INH) are related to outcome in sepsis, a relative deficiency of C1-INH might contribute to the development of fatal complications. At present few data on the periperative course of C1-INH plasma levels have been published. In our study the early perioperative course of C1-INH in relation to the acute phase protein interleukin-6 (IL-6) was investigated in order to assess one possible important aspect of the balance between anti-and proinflammatory mediators.

Methods

In 19 consecutive patients undergoing elective oropharynx tumorresection functional C1-INH was measured by chromogenic substrate assay Berichrom^® C1-Inactivator, the total quantity by single radial imunodiffusion assay NOR-Partigen^® and cytokine IL-6 levels by MEDGENIX IL-6-45 MIN-EASIA. Samples were taken before operation (tl), on ICU admission (t2) and on the first postoperative day (t3).

Results

The mean operation time was 9 h (range: 4:05 to 14:40 h) and all patients showed an uncomplicated ICU course up to 86 h. IL-6 levels increased from t1 to t2 (P < 0.01), whereas C1-INH functional levels declined tendencially and antigenic levels dropped (P = 0.024). Levels of C1-INH at t3 returned to preoperative values and IL-6 declined.

Conclusion

As expected (postoperative agression syndrome) IL-6 increased significantly. Surprisingly, plasma levels of the anti-inflammatory acute phase protein C1-INH remained normal or even declined. On the first postoperative day C1-INH and IL-6 levels tended to return to preoperative values. This was associated with uncomplicated clinical course. We suggest, that this short period of disproportion between pro- and anti-inflammatory mediators may increase the `second hit' risk, if it is longer lasting.

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