01 Jan 10
Posted in Fluid management at 13:37 by Laci
By M Sossdorf, S Marx, B Schaarschmidt, G Otto, R Claus, K Reinhart, C Hartog and W Loesche
Critical Care 2009, 13:R208
Hydroxyethyl starch (HES) solutions are widely used for volume replacement therapy but are also known to compromise coagulation, impair renal function and increase long-term mortality. To test the hypotheses that HES 130/0.4 has less adverse effects than HES 200/0.5 and exerts anti-inflammatory properties we compared the effects of HES130/0.4, HES200/0.5 and saline on in vitro haemostasis and pro-inflammatory platelet function.
Methods
Whole blood samples from healthy volunteers were mixed with 6% HES130/0.4, 10% HES200/0.5, or normal saline to achieve a final haemodilution rate of 10 % or 40 %. Haemostatic capacity was characterised by thromboelastography (ROTEM) and measurement for FXIIIa activity. Platelet activation and pro-inflammatory platelet functions were characterised by flow cytometry measuring the platelet activation marker CD62P and binding of fibrinogen to platelets as well as the formation of heterotypic platelet-leukocyte conjugates.
Results
Compared to saline, HES130/0.4 dose-dependently impaired formation and firmness of the fibrin clot but did not affect the fibrin-crosslinking activity of FXIIIa. At 40 % but not at 10 % haemodilution rate HES200/0.5 also increased platelet fibrinogen binding and both HES solutions increased expression of CD62P, the main receptor for platelet-leukocyte adhesion. HES130/0.4 but not HES200/0.5 increased formation of platelet-neutrophil conjugates and, to a lesser degree, platelet-monocyte conjugates.
HES130/0.4 impairs haemostasis and stimulates pro-inflammatory blood platelet function
Conclusions
Our data demonstrate that HES130/0.4 has similar adverse effects as HES200/0.5. In particular, both types of HES impair coagulation capacity and stimulate rather than attenuate pro-inflammatory platelet function.
Permalink
05 Nov 09
Posted in Fluid management at 1:21 by Laci
By J Lowell, C Schifferdecker, D Driscoll, P Benotti, B Bistrian
Crit Care Med 1990;18:728
The incidence and consequences of fluid overload in the surgical ICU (SICU) have not been well defined, but may influence length of stay, days requiring mechanical ventilation, and mortality. Forty-eight consecutive patients admitted to our SICU were prospectively monitored for acute changes in weight and its impact on clinical management and outcome. When defined as a gain >10% from their preoperative or premorbid weight (or an approximately 20% increase in total body water), 40% of patients had fluid overload. Patients were divided into three groups: those who had gained <=10%, those with a weight gain between 11% and 20%, and those with >20% increase in weight. Significant differences were found with respect to vasopressor dependence, colloid administration, and mortality. When indexed by initial Acute Physiology and Chronic Health Evaluation (APACHE H) mortality prediction scores, all groups had similar degrees of illness. On average, presumably due to volume limitations, patients were inadequately nourished during 85% of their SICU stay. Our results suggest that the morbidity of fluid overload can be significant, and warrants a fresh look at the methods of intraoperative fluid resuscitation.
Permalink
03 Nov 09
Posted in Fluid management, Monitoring at 2:27 by Laci
By D Lahner, B Kabon, C Marschalek, A Chiari, G Pestel, A Kaider, E Fleischmann and H Hetz
Br. J. Anaesth. 2009 103: 346-351
Fluid management guided by oesophageal Doppler monitor has been reported to improve perioperative outcome. Stroke volume variation (SVV) is considered a reliable clinical predictor of fluid responsiveness. Consequently, the aim of the present trial was to evaluate the accuracy of SVV determined by arterial pulse contour (APCO) analysis, using the FloTracTM/VigileoTM system, to predict fluid responsiveness as measured by the oesophageal Doppler.
Methods
Patients undergoing major abdominal surgery received intraoperative fluid management guided by oesophageal Doppler monitoring. Fluid boluses of 250 ml each were administered in case of a decrease in corrected flow time (FTc) to <350 ms. Patients were connected to a monitoring device, obtaining SVV by APCO. Haemodynamic variables were recorded before and after fluid bolus application. Fluid responsiveness was defined as an increase in stroke volume index >10%. The ability of SVV to predict fluid responsiveness was assessed by calculation of the area under the receiver operating characteristic (ROC) curve.
Results
Twenty patients received 67 fluid boluses. Fifty-two of the 67 fluid boluses administered resulted in fluid responsiveness. SVV achieved an area under the ROC curve of 0.512 [confidence interval (CI) 0.32–0.70]. A cut-off point for fluid responsiveness was found for SVV > 8.5% (sensitivity: 77%; specificity: 43%; positive predictive value: 84%; and negative predictive value: 33%).
Conclusions
This prospective, interventional observer-blinded study demonstrates that SVV obtained by APCO, using the FloTracTM/VigileoTM system, is not a reliable predictor of fluid responsiveness in the setting of major abdominal surgery.
Permalink
24 Oct 09
Posted in Fluid management at 0:46 by Laci
By D Chappell, M Jacob, K Hofmann-Kiefer, P Conzen, M Rehm
Anesthesiology 2008;109:723-740
Replacement of assumed preoperative deficits, in addition to generous substitution of an unsubstantiated increased insensible perspiration and third space loss, plays an important role in current perioperative fluid regimens. The consequence is a positive fluid balance and weight gain of up to 10 kg, which may be related to severe complications. Because the intravascular blood volume remains unchanged and insensible perspiration is negligible, the fluid must accumulate inside the body. This concept brings into question common liberal infusion regimens. Blood volume after fasting is normal, and a fluid-consuming third space has never been reliably shown. Crystalloids physiologically load the interstitial space, whereas colloidal volume loading deteriorates a vital part of the vascular barrier. The endothelial glycocalyx plays a key role and is destroyed not only by ischemia and surgery, but also by acute hypervolemia. Therefore, undifferentiated fluid handling may increase the shift toward the interstitial space. Using the right kind of fluid in appropriate amounts at the right time might improve patient outcome.
Permalink
« Previous entries Next Page » Next Page »