Oral premedication of cloridine to reduce cerebrospinal pressure in patients with spinal anesthesia

Abstract

S351 INTRODUCTION: Clonidine, an alpha2-agonist, has been reported to decrease cerebral blood flow [1,2]. The purpose of this study was to examine the effect of oral clonidine on cerebrospinal pressure. METHODS: The study protocol was approved by our Ethical Committee. We studied 40 ASA I or II adult patients scheduled for spinal anesthesia. The Queckenstedt's test was given to all patients to exclude spinal occlusion. They were randomly allocated to two groups. Group 1 (n=20) was the control group given no premedication. Group 2 (n=20) received 0.05 mg/kg of clonidine orally approximately 1 hr before the anesthesia. Each patient was given an intravenous infusion of lactated Ringer's solution 7-10 ml/kg 1 hr before anesthesia. After recording control blood pressure and heart rate, the patient was placed in a lateral recumbent position. After lumbar puncture, cerebrospinal pressure was measured through a 23G needle before the injection of local anesthetics. RESULTS: The mean age, weight and height of the patients were not significantly different between the two groups. The heart rate and mean blood pressure in the operation room and during the lumber puncture were significantly decreased in Group 2 (p < 0.05). Cerebrospinal pressure was significantly lower in Group 2 (p < 0.05). CONCLUSIONS: In this study, cerebrospinal pressure was reduced by oral clonidine administration. We assumed that reduction of cerebrospinal pressure was affected by the cerebral blood flow decreased which was affected by the use of clonidine. The anxiolysis effect of clonidine also supposed to reduce cerebrospinal pressure. We concluded that oral clonidine premedication reduced cerebrospinal pressure and that it is therefore useful for patients with intracranial hypertension. (Figure 1)Figure 1