Vasospasm After Craniopharyngioma Surgery: Can We Prevent It?

BACKGROUND: Vasospasm after craniopharyngioma surgery, although rare, has been reported. Hypotheses regarding possible causative factors, including major vessel handling during surgery and tumor cyst fluid spillage, do not explain vasospasm occurring in the late postoperative period. We have attempted to consider the probable pathogenic mechanisms of this complication and measures to prevent it. METHODS: Of 60 patients operated for craniopharyngiomas over a period of 4 years, 6 who had clinical and radiologically demonstrable vasospasm were identified. Each case was analyzed retrospectively, and relevant variables were studied. RESULTS: Five of the 6 patients developed vasospasm in the second or third week after surgery. Only 2 of these patients had a favorable outcome. There was significant altered fluid balance during this period; however, patients remained misleadingly eunatremic. This most often coincided with the transition period from syndrome of inappropriate antidiuretic hormone to diabetes insipidus (DI) and the period after steroid taper to minimal dose. CONCLUSIONS: Major vessel handling during radical craniopharyngioma surgery is likely to predispose them to spasm, accentuated by rapid shifts of fluid and electrolytes during different phases of DI. This is further complicated by a relative hypocortisolic state caused by tendency to taper off steroids early. Hypocortisolism masks DI leading to dehydration and possibly vasospasm. Once vasospasm develops, it is not easy to reverse. Radiologic reversal with intra-arterial nimodipine may not translate into a good clinical response. Therefore, prudence lies in its prevention. Close monitoring of fluids and electrolytes with optimal steroid cover is necessary until stabilization of DI to prevent this complication.