Effects of 10% Pentastarch Infusion on the Cerebral Blood Flow and Cerebral Metabolic Rate for Oxygen in Canine Hemorrhagic Shock Model / 대한마취과학회지

BACKGREOUND: Cerebral damage caused by hemorrhagic shock presents an important challenge for critical care medicine. The type of fluid to resuscitate hemorrhagic shock is important for the outcome of such patients. Pentastarch is low-molecular-weight hydroxyethyl starch, which increases cerebral blood flow (CBF) by plasma volume expansion and compensatory vasodilation, and improves the microcirculation in the ischemic brain area by reducing the blood viscosity. METHODS: The authors continuously determined CBF and CMRO2 in 10 mongrel dogs weighing 20.1 +/- 0.8 kg with posterior sagittal sinus outflow method. Dogs were subjected to the 20 minute-period of hemorrhagic shock to a mean arterial pressure of 40 mmHg. The shock phase was followed by resuscitation with the same volume of 10% pentastarch as blood loss. The authors assessed the changes of CBF, CMRO2, and CBF/CMRO2 ratio immediately and 30, 60, 90, 120 minutes after pentastarch infusion. Brain water content was assessed by the wet-dry weight method. RESULTS: CBF was increased above the control level, immediately and 30 minutes after 10% pentastarch infusion (p<0.05), and approximated to the control level for the remaining time. CMRO2 was increased, immediately and 30, 60, 90 minutes after 10% pentastarch infusion (p<0.05), and approximated to the control level at 120 minutes. CBF/CMRO2 ratio was recovered to the control level after 10% pentastarch infusion. Brain water content was not significantly different from the normal value of dogs. CONCLUSION: 10% pentastarch may be used with safety to resuscitate hemorrhagic shock because it recovers the balance between the cerebral oxygen supply and demand, and does not cause cerebral edema.

Intraoperative Normovolemic Hemodilution in Patients Undergonig Posterolateral Spinal Fusion: Safety and Efficacy / 대한마취과학회지

BACKGROUND: The implementation of intraoperative normovolemic hemodilution is a strategy used in an attempt to diminish the need for or obviate allogeneic transfusion and to avert the potential complications. The goal of this study was to evaluate the safety and efficacy of moderate intraoperative normovolemic hemodilution. METHODS: Fifteen patients scheduled for posterolateral spinal fusion underwent intraoperative normovolemic hemodilution with 10% pentastarch to a target hematocrit level of 25% (hemodilution group). All units of blood procured by hemodilution and additional allogeneic blood was transfused in the perioperative period to maintain the hematocrit level of>25%. We investigated the effect of hemodilution on whole blood coagulation as measured by the thromboelastography and, evaluated its efficacy of decreasing the need for allogeneic blood transfusion as compared to the nonhemodilution group, retrospectively. RESULTS: Hemodilution with pentastarch caused a decrease in response and coagulation time (p<0.01) but did not influence on the alpha angle and maximum amplitude on thromboelstogram. Amount of transfusion of allogeneic blood was 4.1 1.7 units for the hemodilution group and 5.0 1.5 units for the nonhemodilution group. Net red blood cell volume ""saved"" from hemodilution was about 120 ml. CONCLUSION: Moderate intraoperative normovolemic hemodilution with pentastarch does not affect the coagulability of whole blood. But its efficacy of decreasing the need for allogeneic blood transfusion is minimal.