BACKGROUND: During carotid endarterectomy (CEA), hemodynamic stability and adequate fluid management are crucial to prevent perioperative cerebral stroke, myocardial infarction and hyperperfusion syndrome. Both pulse pressure variation (PPV) and stroke volume variation (SVV), dynamic preload indices derived from the arterial waveform, are increasingly advocated as predictors of fluid responsiveness in mechanically ventilated patients. The aim of this study was to evaluate the accuracy of PPV and SVV for predicting fluid responsiveness in patients undergoing CEA. METHODS: Twenty seven patients undergoing CEA were enrolled in this study. PPV, SVV and cardiac output (CO) were measured before and after fluid loading of 500 ml of hydroxyethyl starch solution. Fluid responsiveness was defined as an increase in CO > or = 15%. The ability of PPV and SVV to predict fluid responsiveness was assessed using receiver operating characteristic (ROC) analysis. RESULTS: Both PPV and SVV measured before fluid loading are associated with changes in CO caused by fluid expansion. The ROC analysis showed that PPV and SVV predicted response to volume loading (area under the ROC curve = 0.854 and 0.841, respectively, P < 0.05). A PPV > or = 9.5% identified responders (Rs) with a sensitivity of 71.4% and a specificity of 90.9%, and a SVV > or = 7.5% identified Rs with a sensitivity of 92.9% and a specificity of 63.6%. CONCLUSIONS: Both PPV and SVV values before volume loading are associated with increased CO in response to volume expansion. Therefore, PPV and SVV are useful predictors of fluid responsiveness in patients undergoing CEA.
Arterial Pressure ; Blood Pressure ; Cardiac Output ; Endarterectomy, Carotid ; Fluid Therapy ; Hemodynamics ; Hetastarch ; Humans ; Myocardial Infarction ; ROC Curve ; Sensitivity and Specificity ; Stroke ; Stroke Volume

Fluid therapy remains an important therapeutic maneuver in managing surgical, medical, and the critically ill intensive care patient. However, the ideal volume replacement strategy remains under debate. The debate on whether patients should be managed with crystalloids, colloids, or both has for many years been mainly a debate about effectiveness. The dispute over crystalloids versus colloids has been enlarged to a colloid versus colloid debate because of the varying properties of different colloids. The natural colloid albumin and artificial colloids such as gelatin, dextran, and hydroxyethyl starch continue to enjoy widespread usage for clinical fluid management. Colloid is an effective plasma volume expander and is able to restore the hemodynamic profile with less total volume than crystalloid. However, colloid is associated with coagulation abnormalities, renal impairment, and allergic reactions. Albumin is considered to be one of the safe colloids. However, due to its cost, albumin cannot be recommended for hypovolemia. Gelatin and dextran can also cause coagulation abnormalities and renal impairment. Dextran is not used anymore due to its high anaphylactic potency. Each hydroxyethyl starch has different properties by concentration, mean molecular weight, molar substitution, and its C2/C6 ratio. New hydroxyethyl starches with a lower mean molecular weight and molar substitution than the old hydroxyethyl starch may be promising by improving volume management therapy with lower risks of coagulation abnormalities and renal impairment. The selection of colloid for plasma volume expansion should be based on the patients' clinical conditions and the characteristics of each colloid.
Colloids ; Critical Illness ; Critical Care ; Dextrans ; Dissent and Disputes ; Fluid Therapy ; Gelatin ; Hemodynamics ; Hetastarch ; Humans ; Hypersensitivity ; Hypovolemia ; Isotonic Solutions ; Molar ; Molecular Weight ; Plasma ; Plasma Substitutes ; Plasma Volume

Several papers on respiratory and critical care published from March 2012 to February 2013 were reviewed. From these, this study selected and summarized ten articles, in which the findings were notable, new, and interesting: effects of high-frequency oscillation ventilation on acute respiratory distress syndrome (ARDS); safety and efficacy of hydroxyethyl starch as a resuscitation fluid; long-term psychological impairments after ARDS; safety and efficacy of dexmedetomidine for sedation; B-type natriuretic peptide-guided fluid management during weaning from mechanical ventilation; adding of daily sedation interruptions to protocolized sedations for mechanical ventilation; unassisted tracheostomy collar of weaning from prolonged mechanical ventilations; and effects of nighttime intensivist staffing on the hospital mortality rates.
Critical Care ; Dexmedetomidine ; Hetastarch ; High-Frequency Ventilation ; Hospital Mortality ; Respiratory Distress Syndrome, Adult ; Resuscitation ; Sepsis ; Tracheostomy ; Weaning

Hydroxyethyl starch (HES) solutions are synthetic non-protein colloid solutions used to treat hypovolemia. However, their use is not free from the risk of allergic reactions. A 42-year-old male was scheduled to undergo aortic-iliac-femoral bypass surgery for the treatment of arteriosclerosis obliterans. He had no history of allergy. Two hours after the start of surgery, and within minutes after HES administration, facial erythema, hypotension and bronchospasm developed. HES infusion was discontinued under the estimation of anaphylaxis. The patient received phenylephrine, ephedrine, diphenhydramine and hydrocortisone with hydration. After restoration of vital signs, surgery was performed without complications.
Adult ; Anaphylaxis ; Arteriosclerosis Obliterans ; Bronchial Spasm ; Colloids ; Diphenhydramine ; Ephedrine ; Erythema ; Hetastarch ; Humans ; Hydrocortisone ; Hypersensitivity ; Hypotension ; Hypovolemia ; Male ; Phenylephrine ; Vital Signs

BACKGROUND: Third-generation hydroxyethyl starch (HES) solutions have been developed to minimize negative effects on hemostasis. In normal pregnancy, the coagulation activity increases, reaching a maximum around term. This study examined the effects of hemodilution with HES 130/0.4 (6%) on blood coagulation in parturients in vivo and in vitro. METHODS: Forty parturients scheduled for cesarean sections were assigned randomly to receive either 500 or 1,000 ml of HES 130/0.4 (6%). Rotation thromboelastometry (ROTEM(R)) measurements were performed before and after administering HES 130/0.4 (6%). In addition, blood samples obtained from 20 randomly selected parturients were diluted 10% to 40% using HES 130/0.4 (6%), and ROTEM(R) measurements were performed before and after dilution. The changes from baseline and the effects of dilution were analyzed by ROTEM(R) parameters. RESULTS: Infusions of 500 or 1,000 ml of HES 130/0.4 (6%) in the parturients altered the clot formation time, alpha angle, and maximal clot firmness, although all remained within normal ranges. HES 130/0.4 (6%) affected in vitro blood coagulation in parturients' blood containing 10, 20, 30, and 40% HES. The clotting time was prolonged at each dilution percentage, but remained within the normal range. Other parameters showed an impairment of the coagulation system. CONCLUSIONS: Blood coagulation in parturients may be compromised at high dilution ratios of HES 130/0.4 (6%) to blood. Nevertheless, the infusion of 1,000 ml of HES 130/0.4 (6%) in normal parturients did not significantly affect blood coagulation.
Blood Coagulation ; Cesarean Section ; Female ; Hemodilution ; Hemostasis ; Hetastarch ; Pregnancy ; Reference Values

BACKGROUND: The aim of this study was to investigate the neuroprotective effects of colloids (albumin and pentastarch) after forebrain global ischemia in rats. METHODS: Thirty male Sprague-Dawley rats were randomly assigned to three groups; control, albumin and pentastarch group (each n = 10). Forebrain ischemia was induced by bilateral common carotid artery occlusion plus hemorrhagic hypotension. The control group received no treatment. The albumin group received 5 ml/kg of 20% albumin after ischemia. The pentastarch group received same volume of albumin after ischemia. Histologic outcomes were measured at 7 days after ischemia in CA1 pyramidal cells of the rat hippocampus. RESULTS: The mean percentage of viable cells in the hippocampal CA1 area was significantly higher in the albumin (47%) compared with the control group (33%) or pentastarch group (33%) (P = 0.001). The percentage of apoptotic cells was significantly lower in the albumin (30%) group than that in the pentastarch (44%) or control group (49%) (P = 0.006). CONCLUSIONS: This study shows that albumin can improve histologic outcomes after forebrain global ischemia compared with pentastarch.
Animals ; Brain Ischemia ; Carotid Artery, Common ; Colloids ; Hetastarch ; Hippocampus ; Humans ; Hypotension ; Ischemia ; Male ; Neuroprotective Agents ; Prosencephalon ; Pyramidal Cells ; Rats ; Rats, Sprague-Dawley

BACKGROUND: Individuals with type O blood are more likely to have reduced factor VIII and von Willebrand factor levels compared to their non-O counterparts. Hydroxyethyl starch (HES), which is widely used for blood volume replacement, can induce coagulopathy. Therefore, we tested whether blood type O patients show more coagulopathy and blood loss than non-O patients after infusion of 6% HES. METHODS: Thirty-four non-O and 20 type O patients scheduled for posterior lumbar interbody fusion (PLIF) involving 3 vertebrae or less from June 2007 to August 2008 were enrolled. Fifteen ml/kg of 6% HES was administered during the operation. Coagulation profiles was checked at pre-infusion (T0), 5 min after the end of infusion (T1), 3 hr after the end of infusion (T2), and 24 hr after the end of infusion (T3). Bleeding was measured during and after surgery for 24 hours. RESULTS: Baseline factor VIII concentration was lower and aPTT was longer in type O patients compared to those of non-O patients. 6% HES infusion decreased most of the coagulation factors at T1 in both groups, which were recovered in a time dependent manner. Factor VIII and aPTT of blood type O patients fell off the normal range at T1. However, other coagulation factors, thromboelastography variables, and blood loss were not different between the groups. CONCLUSIONS: Despite inborn low factor VIII which further decreased shortly after HES infusion, blood type O patients did not show more blood loss than non-O blood type after 15 ml/kg of HES infusion in PLIF surgery.
Blood Coagulation Factors ; Blood Volume ; Factor VIII ; Hemorrhage ; Hetastarch ; Humans ; Reference Values ; Spine ; Thrombelastography ; von Willebrand Factor

BACKGROUND: Allogeneic blood transfusion has risks from transfusion-transmitted pathogens. Blood management programs are widely used for cardiovascular or orthopedic surgery, but there have been few studies that have focused on blood conservation during brain tumor resection surgery. The purpose of this study was to evaluate the benefits of blood management for brain tumor surgery. METHODS: A total of 26 patients undergoing brain tumor resection surgery were included in the study. Thirteen patients with meningiomas, 10 patients with malignant gliomas and 3 patients with other tumors were included. The surgical blood loss was estimated by preoperative imaging studies, and the tumors that could be operated with minimal bleeding were excluded. Preoperative autologous donation (PAD) was done when the expected amount of surgical bleeding surpassed 300 mL. Preoperative embolization was performed in the patients with meningiomas whenever it was technically feasible. Six percent hydroxyethyl starch 130/0.4 (Voluven) was administered during anesthesia for expanding the blood volume and we performed meticulous surgical techniques for minimizing the blood loss. RESULTS: The amount of bleeding was less than 300 mL in 69.2% of the patients. Preoperative autologous blood was donated by 10 patents and 20% of the PAD units were discarded. Five patients with meningimas received preoperative embolization. None of the patients, except for one patient who had massive bleeding of 7,000 mL, were transfused allogeneic blood. Eighty one percent of the patients received Voluven without complications. CONCLUSION: Multiple strategies that include preoperative embolization, proper surgical techniques for minimizing blood loss, PAD and hydroxyehtyl starch could effectively decrease the amount of allogenic blood transfused during brain tumor resection surgery.
Anesthesia ; Blood Loss, Surgical ; Blood Transfusion ; Blood Transfusion, Autologous ; Blood Volume ; Brain ; Brain Neoplasms ; Glioma ; Hemorrhage ; Hetastarch ; Humans ; Meningioma ; Orthopedics ; Starch

BACKGROUND: The fluid kinetics of intravenously infused colloid during inhalation anesthesia and hemorrhage have not been investigated. We therefore assessed fluid space changes during infusion of hydroxyethyl starch solution after hemorrhage in conscious and desflurane-anesthetized individuals. METHODS: Following the donation of 400 ml of blood, 500 ml of hydroxyethyl starch solution was infused over 20 minutes into wakeful and desflurane-anesthetized volunteers. Blood was repeatedly sampled to measure hemoglobin concentration, a marker of plasma dilution, and fluid kinetic analysis was performed to evaluate changes in fluid space. RESULTS: Using a fluid kinetic model, we found that the mean volume of fluid space was 7,724 +/- 1,788 ml in wakeful volunteers and 6,818 +/- 4,221 ml in anesthetized volunteers, and the elimination rate constants were 7.1 +/- 3.5 ml/min and 19.4 +/- 4.6 ml/min, respectively. CONCLUSIONS: Infusion of colloid after mild hemorrhage resulted in similar expansions of plasma volume in desflurane-anesthetized and conscious individuals. During anesthesia, however, the expansion of plasma volume by colloid was decreased and of shorter duration than observed in conscious patients.
Anesthesia ; Anesthesia, General ; Anesthesia, Inhalation ; Blood Donors ; Colloids ; Fluid Therapy ; Hemoglobins ; Hemorrhage ; Hetastarch ; Humans ; Kinetics ; Plasma ; Plasma Volume

BACKGROUND: Total knee arthroplasty (TKR) is associated with a significant loss of blood. Fluid substitution with crystalloid or colloid solutions to correct perioperative hypovolemia is essential. Colloid solutions, and especially hydroxyethyl starches (HES), are used to treat hypovolemia, but they may affect blood coagulation. The purpose of this study was to test the efficacy and the safety of colloid solutions in patients undergoing TKR. METHODS: The patients undergoing TKR were divided into a group that underwent fluid management with Voluven(R) (n = 22) and a group that was managed with Hextend(R) (n = 24). The blood loss, the autotransfused blood volume, the hemoglobin level, the allogenic blood requirement, the urine output and the complications were assessed. RESULTS: There were no significant differences in the amount of blood loss, the autotransfused blood volume, the allogenic requirement, the urine output and the complications between the two groups. CONCLUSIONS: Voluven(R) and Hextend(R) are equally efficacious plasma volume substitutes when performing TKR with an autotransfusion of drained blood.
Arthroplasty ; Blood Coagulation ; Blood Transfusion, Autologous ; Blood Volume ; Colloids ; Hemoglobins ; Hetastarch ; Humans ; Hypovolemia ; Isotonic Solutions ; Knee ; Plasma Volume ; Postoperative Hemorrhage