Tatara T, Tsuzaki K
Department of Anesthesia, Saiseikai Kanagawaken Hospital, Kanagawaken Traffic Trauma Center, Yokohama, Japan.
Crit Care Med. 1998 Mar;26(3):470-6. doi: 10.1097/00003246-199803000-00017.
To determine whether the segmental multifrequency bioelectrical impedance analysis may improve the prediction for intraoperative changes in extracellular water volume (deltaECW) compared with whole body multifrequency bioelectrical impedance analysis in abdominal surgical patients.
Prospective, consecutive sample.
Surgical operative patients in a university-affiliated city hospital.
Thirty patients who underwent elective gastrointestinal surgery.
Multifrequency bioelectrical impedance analysis was conducted preoperatively (before the induction of anesthesia) and postoperatively (after recovery from anesthesia). Resistance values fitted at zero frequency (R0) in the whole body and in each body segment (arm, trunk, and leg) were determined by performing nonlinear curve-fitting and subsequent extrapolation. DeltaECW values were estimated from the whole body resistance between wrist and ankle using two different prediction formulas. In segmental multifrequency bioelectrical impedance analysis, however, ECW was obtained as the sum of each body segment (arms, trunk, and legs) using the equation newly derived from the cell suspension theory. DeltaECW estimated from both measurements were compared with net fluid balances during surgery.
R0 in whole body and all body segments significantly decreased after surgery (p < .0001). The most striking decrease in post/preoperative ratios was found in the R0 in the trunk. The post/preoperative ratio of the R0 value in the trunk was significantly lower than the post/preoperative ratio of the R0 value in the leg (p = .0007). DeltaECW from segmental multifrequency bioelectrical impedance analysis was similar to net fluid balance (r2 = .80, bias = -0.03 L), whereas whole body multifrequency bioelectrical impedance analysis resulted in considerable underestimations of deltaECW (r2 = .50, .51, bias = 0.95, 0.53 L).
The difference in the prediction of deltaECW between whole body and segmental multifrequency bioelectrical impedance analysis may be explained by the significant decrease in the resistance of the trunk, which contributed only minimally to the whole body resistance. Segmental multifrequency bioelectrical impedance analysis provides a better approach to predict ECW changes in critically ill patients with nonuniform fluid distribution.
与全身多频生物电阻抗分析相比，确定节段性多频生物电阻抗分析是否能改善对腹部手术患者术中细胞外液量变化（deltaECW）的预测。
前瞻性连续样本。
大学附属医院的手术患者。
30例行择期胃肠手术的患者。
术前（麻醉诱导前）和术后（麻醉恢复后）进行多频生物电阻抗分析。通过进行非线性曲线拟合和随后的外推法，确定全身及每个身体节段（手臂、躯干和腿部）在零频率时的电阻值（R0）。使用两种不同的预测公式，根据手腕和脚踝之间的全身电阻估计DeltaECW值。然而，在节段性多频生物电阻抗分析中，根据细胞悬浮理论新推导的公式，将每个身体节段（手臂、躯干和腿部）的电阻相加得到ECW。将两种测量方法估计的DeltaECW与手术期间的净液体平衡进行比较。
术后全身及所有身体节段的R0均显著降低（p < 0.0001）。躯干R0的术前/术后比值下降最为显著。躯干R0值的术前/术后比值显著低于腿部R0值的术前/术后比值（p = 0.0007）。节段性多频生物电阻抗分析得出的DeltaECW与净液体平衡相似（r2 = 0.80，偏差 = -0.03 L），而全身多频生物电阻抗分析导致对DeltaECW的显著低估（r2 = 0.50、0.51，偏差 = 0.95、0.53 L）。
全身和节段性多频生物电阻抗分析在预测DeltaECW方面的差异，可能是由于躯干电阻显著降低，而躯干电阻对全身电阻的贡献极小。节段性多频生物电阻抗分析为预测液体分布不均匀的重症患者的ECW变化提供了更好的方法。
