Hoff Reinier G, van Dijk Gert W, Algra Ale, Kalkman Cor J, Rinkel Gabriel J E
Rudolf Magnus Institute of Neuroscience, Department of Perioperative and Emergency Care, Q 04.2.303, University Medical Center Utrecht, PO Box 85500, Utrecht 3508 GA, The Netherlands.
Neurocrit Care. 2008;8(3):391-7. doi: 10.1007/s12028-007-9043-x.
Patients with aneurysmal subarachnoid hemorrhage (SAH) are at risk for circulatory volume depletion, which is a risk factor for delayed cerebral ischemia (DCI). In a prospective observational study we assessed the effectiveness of fluid administration based on regular evaluation of the fluid balance in maintaining normovolemia.
A total of 50 patients with aneurysmal SAH were included and were treated according to a standard protocol aimed at maintaining normovolemia. Fluid intake was adjusted on the basis of the fluid balance, which was calculated at 6-h intervals. Circulating blood volume (CBV) was measured by means of pulse dye densitometry (PDD) on alternating days during the first 2 weeks after SAH.
Of the 265 CBV measurements, 138 (52%) were in the normovolemic range of 60-80 ml/kg; 76 (29%) indicated hypovolemia with CBV < 60 ml/kg; and 51 (19%) indicated hypervolemia with CBV > 80 ml/kg. There was no association between CBV and daily fluid balance (regression coefficient beta = -0.32; 95% CI: -1.81 to 1.17) or between CBV and a cumulative fluid balance, adjusted for insensible loss through perspiration and respiration (beta = 0.20; 95% CI: -0.31 to 0.72).
Calculations of fluid balance do not provide adequate information on actual CBV after SAH, as measured by PDD. This raises doubt whether fluid management guided by fluid balances is effective in maintaining normovolemia.
动脉瘤性蛛网膜下腔出血（SAH）患者存在循环血容量减少的风险，这是延迟性脑缺血（DCI）的一个危险因素。在一项前瞻性观察研究中，我们基于对液体平衡的定期评估来评估液体输注在维持正常血容量方面的有效性。
共纳入50例动脉瘤性SAH患者，并按照旨在维持正常血容量的标准方案进行治疗。根据每6小时计算一次的液体平衡来调整液体摄入量。在SAH后的前2周内，每隔一天通过脉搏染料密度测定法（PDD）测量循环血容量（CBV）。
在265次CBV测量中，138次（52%）处于60 - 80 ml/kg的正常血容量范围内；76次（29%）显示血容量不足，CBV < 60 ml/kg；51次（19%）显示血容量过多，CBV > 80 ml/kg。CBV与每日液体平衡之间无关联（回归系数β = -0.32；95%置信区间：-1.81至1.17），在调整了因出汗和呼吸导致的不显性失液后，CBV与累积液体平衡之间也无关联（β = 0.20；95%置信区间：-0.31至0.72）。
通过PDD测量，液体平衡的计算并不能提供关于SAH后实际CBV的充分信息。这引发了对基于液体平衡指导的液体管理在维持正常血容量方面是否有效的质疑。
