Mannitol Increases Cerebral Arteriovenous Oxygen Difference in Patients Undergoing Craniotomy

顱內手術麻醉中使用邁尼妥可增加動脈及頸靜脈球血氧容量之差異

劉錦棠(Jiin-Tarng Liou) ； 呂炳榮(Ping-Wing Lui) ； 許正中(Ching-Chung Shu) ； 林聖瀚(Shang-Han Lin) ； 沈志隆(Chin-Long Shen) ； 李顯榮(Shane-Rong Lee) ； 李德譽(Tak-Yu Lee)

《Acta Anaesthesiologica Sinica》 33卷2期 (1995/06) Pp. 91-96

摘要

Background: Monitoring the jugular venous oxygen saturation (SjVO_2) and cerebral arteriovenous oxygen difference (AVDO_2) is valuable in detecting cerebral ischemia. In the present study, we investigated the effect of mannitol on SjVO_2 and AVDO_2 in patients undergoing craniotomy. Methods: We studied 25 ASA class II-III patients undergoing craniotomy. Anesthesia was induced with thiopental, fentanyl and vecuronium. Immediately after induction, a 16-gauge central venous catheter was placed in the internal jugular vein, ipsilateral to the lesion side with cephalic insertion and anchorage in the jugular bulb. Anesthesia was maintained with continuous infusion of fentanyl (10 μg/kg /h), 0.5-1% isoflurane in 60% oxygen (oxygen/air) and supplemental dose of vecuronium for muscle relaxation as needed. Samples of arterial and jugular venous blood were obtained for the measurements of SjVO_2 and AVDO_2 in the following time intervals: (1) normocapnia (PaCO_2 38 - 40 mmHg); (2) hypocapnia (PaCO_2 28 - 30 mmHg); and (3) 30 min after mannitol (0.5 g/kg) infusion. Results: Hyperventilation resulted in a significant decrease in SjVO_2 (96% patients) and increase in AVDO_2 (88% patients). Hypocapnia followed by mannitol administration led to a further decrease and increase of SjVO_2 and AVDO_2 in 72% and 68% patients, respectively. Conclusions: Mannitol may produce a further reduction in SjVO_2 accompanied by an increase in AVDO_2, suggesting a reduction of cerebral blood flow (CBF) during hyperventilation. Therefore, it should be given cautiously in neurosurgical patients under hyperventilation.

關鍵字

Jugular bulb oxygen saturation ； Arteriovenous oxygen difference ； Hyperventilation ； Mannitol ； Cerebral blood flow

並列摘要

背景：頸靜脈球之血氧飽和度與動靜脈血氧容量差異之監測，可能是一種早期發現腦部缺血之重要工具。本實驗主要目的是在顱內手術過程中使用上述方法，以評估過度換氣和邁尼妥之使用，對腦部血流之影響。方法：取得醫院核可與病患同意後，退出25位ASA體位II－III將進行顱骨切開術之病患。以thiopental，fentanyl和vecuronium完成麻醉誘導後使用16號20公分長之中心靜脈導管以反方向放置於內頸靜脈，放置時盡可能到頸靜脈球內並與病灶同側為主，某些病患經頸部X光照像以確定導管之位置，手術中以fentanyl（每小時每公斤10微克）和適量之間vecuronium維持麻醉，並於（1）正常動脈血二氧化碳含量（38－40 mmHg）；（2）低動脈血二氧化碳含量（28－30mmHg）；（3）給予邁尼妥後30分鐘等三種不同條件下，取得動脈和頸靜脈血之氣體分析並換算與比較。結果：過度交換氣體將會引起頸靜脈球血氧飽合度減少（96%之病患）和動靜脈血氧容量差之增加（88%之病患），且於過度換氣之條件下邁尼妥之使用會引起減少和增加程度更加嚴重。結論：在顱內手術時過度換氣之條件下，合併邁尼妥之使用可能導至腦部缺血更加嚴重。因此，當需要合併使用時必須小心謹慎。

並列關鍵字

頸靜脈球血氧飽和度 ； 動靜脈血氧容量差 ； 過度換氣治療 ； 邁尼妥 ； 腦部血流