[Comparative evaluation of the hemodynamic effect of 6% hydroxyethyl starch 130/0.42 solution versus 4% modified liquid gelatin solution in cardiosurgical patients]

The study included 20 patients who underwent a 6% HES 130/0.42 (venofundin, B-Braun) infusion test. A 4% MLG (gelofusine, B-Braun) infusion test was carried out in 16 patients. The baseline hemodynamic parameters did not differ before infusion of the compared solutions. In the HES 130 group, the mean cardiac index (CI) increase of 23% was observed in 9 cases; its reduction was seen in 7 cases. In the MLG group, the mean CI increase of 26% was noted in 14 patients and its decrease was in 10. With increased CI in response to the venofundin test infusion, there were statistically significant increases in central blood volume (CBV) by 14.6%, global end-diastolic volume (GEDV) by 13%, right atrial pressure (RAP) by 50%, and pulmonary artery wedge pressure (PAWP) by 35.5%. In the increased CI group, gelofusine caused statistically significant increases in CBV by 19%, GEDV by 7%, RAP by 33%, and PAWP by 29%. When CI was decreased in the use of MLG, there were statistically significant increases in CBV by 20%, GEDV by 17%, RAP by 49%, and PAWP by 20.5%. HES 130/0.4 resulted in increases in CBV by 18%, GEDV by 16.6%, RAP by 80%, and PAWP by 43%. 6% HES 130/0.42 and 4% MLG in doses of 500 ml had a similar hemodynamic effect in the infusion test during 30 min. Volume load with the test colloid solutions allows the functional reserves of the cardiovascular system to be estimated in cardiosurgical patients. Inotropic drugs are indicated for patients with lower cardiac output and infusion therapy is performed in those with considerably increased CI.

Acute normovolemic hemodilution in a Jehovah's Witness patient: a case report

Patients who are Jehovah's Witnesses refuse blood transfusions and blood products as a matter of faith. For surgical procedures during which substantial blood loss is possible, their refusal presents a challenge. 'Anesthetists must generally respect the requests of adults not to receive blood and thus should have a clear understanding of how they will respond in the event of bleeding. Several blood conservation techniques are available for consideration, including acute normovolemic hemodilution. This technique entails the preoperative phlebotomy of whole blood that contains a high concentration of red blood cells and coagulation Patiefactors, while replacing the lost volume with a crystalloid and/or colloid infusion. The procured whole blood can then be transfused back during or after the procedure as a treatment of hypovolemia. Leaving the procured blood continuously attached to the patient through the collection tubing makes the procedure acceptable to most Jehovah's Witness patients. Current literature is unclear when this technique should be used. In this particular case, acute normovolemic hemodilution contributed to the successful outcome of an anemic Jehovah's Witness who was undergoing major surgery.

Thrombelastography during an acute normovolemic hemodilution in patient undergoing radical retropubic prostatectomy

The aim of our study was to monitor a patient undergoing radical prostatectomy (RP) with an extraordinary large blood loss of 3600 ml. The perioperative bleeding was minimalized through an acute normovolemic hemodilution (ANH). During the procedure we monitored the patient's hemocoagulation profile. ANH is one of the possibilities for practical and pragmatic hemotherapy. It is a safe and effective method when facing massive blood loss or when it is necessary to temporarily replace or substitute the blood with a fluid during the operation (through a transfusion of allogeneic blood); and the patient benefits from the procedure. We argue that during ANH, the hypercoagulatory state appears in the patient--and even during the introduction of a combined solution of both crystalloids and colloids. In fact, during ANH it should not be recommended to provide a substitute for the patient's blood using only a single crystalloid solution alone (Tab. 2, Ref. 16).

Cardiopulmonary interventions to decrease blood loss and blood transfusion requirements for liver resection

BACKGROUND

Blood loss during liver resection is one of the most important factors affecting the peri-operative outcomes of patients undergoing liver resection.

OBJECTIVES

To determine the benefits and harms of cardiopulmonary interventions to decrease blood loss and to decrease allogeneic blood transfusion requirements in patients undergoing liver resections.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, and Science Citation Index Expanded until November 2008 for identifying the randomised trials.

SELECTION CRITERIA

We included all randomised clinical trials comparing various cardiopulmonary interventions aimed at decreasing blood loss and allogeneic blood transfusion requirements in liver resection. Trials were included irrespective of whether they included major or minor liver resections, normal or cirrhotic livers, vascular occlusion was used or not, and irrespective of the reason for liver resection.

DATA COLLECTION AND ANALYSIS

Two authors independently identified trials for inclusion and independently extracted data. We analysed the data with both the fixed-effect and the random-effects models using RevMan Analysis. For each outcome we calculated the risk ratio (RR), mean difference (MD), or standardised mean difference (SMD) with 95% confidence intervals (CI) based on intention-to-treat analysis or available case-analysis. For dichotomous outcomes with only one trial included under the outcome, we performed the Fisher's exact test.

MAIN RESULTS

Nine trials involving 587 patients satisfied the inclusion criteria. The interventions included low central venous pressure (CVP), autologous blood donation, haemodilution, haemodilution with controlled hypotension, and hypoventilation. Only one or two trials were included under most comparisons. All trials had a high risk of bias. There was no significant difference in the peri-operative mortality or other peri-operative morbidity. None of the trials reported long-term survival or liver failure.The risk ratio of requiring allogeneic blood transfusion was significantly lower in the haemodilution and haemodilution with controlled hypotension groups than the respective control groups. Other interventions did not show significant decreases of allogeneic transfusion requirements.

AUTHORS' CONCLUSIONS

None of the interventions seem to decrease peri-operative morbidity or offer any long-term survival benefit. Haemodilution shows promise in the reduction of blood transfusion requirements in liver resection surgery. However, there is a high risk of type I (erroneously concluding that an intervention is beneficial when it is actually not beneficial) and type II errors (erroneously concluding that an intervention is not beneficial when it is actually beneficial) because of the few trials included, the small sample size in each trial, and the high risk of bias. Further randomised clinical trials with low risk of bias and random errors assessing clinically important outcomes such as peri-operative mortality are necessary to assess any cardiopulmonary interventions aimed at decreasing blood loss and blood transfusion requirements in liver resections. Trials need to be designed to assess the effect of a combination of different interventions in liver resections.

Acute normovolemic hemodilution in sickle cell patient--a case report

Sickle cell disease patients with relatively high hemoglobin (> or = 12 g x dl) and those who have elevated alloimmunizations antibodies with rare phenotype subgroups, are problems challenging anesthesiologists. Acute Normovolemic Hemodilution (ANH) is rarely used in the perioperative management of homozygous sickle cell disease (SCD) in patients undergoing surgery. We hereby present a case in which ANH was used successfully. A 22 year old male patient with known homozygous sickle cell disease undergoing orthopedic surgery, underwent Acute Normovolemic Hemodilution (ANH) because of the absence of blood and suitable blood donors and high hemoglobin level. Just before establishing spinal anesthesia, a 400 ml blood was extracted from patient and then replaced by 6 % Hydroxyethylstarch HES solution.The surgery was performed uneventfully under spinal analgesia. Patient was discharged 48 hours later. A week later, his follow up visit showed no complications and his lab work returned to basic levels. We recommend the ANH technique as an on hand tool in the perioperative anesthetic management of sickle cell disease patients who have high Hb S with relatively high Hb levels, and in those special patients who have no blood available because of high alloimmunization antibodies or rare phenotype blood groups.

[Changes in hemodynamics and volemic status during intraoperative blood exfusion in patients with chronic heart failure]

Forty-five patients with dilated cardiomyopathy, NYHA Functional Classes III-IV chronic heart failure with left ventricular ejection fraction 26.98+/-7%, who had undergone surgical left ventricular remodeling using an extracardiac conduit in combination with mitral or tricuspid valve correction and blood exfusion, were examined. Central hemodynamic monitoring was performed, by using a Swan-Ganz catheter in all the patients at surgery. In 11 patients, transpulmonary thermodilution in combination with pulmonary artery catheterization with a Swan-Ganz catheter (PICCO-Plus + VOLEF, Pulsion, Germany) was used in 11 patients to monitor central hemodynamics. Right atrial blood autoexfusion was carried out at a volume of 6-10 ml/kg prior to extracorporeal circulation. At blood sampling, blood pressure (BP), heart rate (HR), central venous pressure (CVP), and pulmonary pressure were in the normal range. There were no significant changes in HR, BP, and CVP after blood exfusion. A significant lowering was noted in systolic and diastolic pulmonary pressure by 20-25%. Under the influence of blood exfusion, there was a reduction in cardiac pump function, which appeared as decreases in stroke index by 24% (p < 0.05) and cardiac index by 18% (p < 0.05). The parameters reflecting left and right ventricular myocardial contractility (functional state index, global ejection fraction, and dPmax) underwent no negative changes. According to the changes in systolic and diastolic BP and total peripheral vascular resistance index, left ventricular postload did not change either. At the same time, global end-diastolic volume index was reduced by 22% (p < 0.05), right cardiac and right ventricular end-diastolic volumes were decreased by 20% (p < 0.05) and 23% (p < 0.05), respectively; the left ventricular end-diastolic volume index tended to be lower. These data suggested that diminished cardiac pump function was caused by a predominant reduction in global preload, as evidenced by volumetric monitoring. At the same time the changes in CVP, BP, and HR did not reflect the altered volemic status. To prevent destabilization of the circulatory system, blood should be sampled just before extracorporeal circulation after aortic cannulation.

Intravascular Fluorocarbon-stabilized Microbubbles Protect Against Fatal Anemia in Rats

It has earlier been hypothesized that intravascular microbubbles, derived from a dodecafluoropentane (DDFP) emulsion, can transport physiologically significant amounts of oxygen in the animal body. To test this notion, anesthetized oxygen breathing rats were rendered severely anemic by bleeding and volume replacement. Rats treated with 0.014 ml/kg of DDFP in a 2% emulsion had normal circulatory parameters and behaved normally when waking up from anesthesia while controls died during anesthesia. Oxygen-breathing intact rats given 0.01 ml/kg of DDFP had muscle oxygen tensions which, for about 2.5 hours, exceeded those of controls by 50-100%. It was further verified in vitro that DDFP-derived microbubbles can exchange oxygen with a surrounding aqueous medium. Extrapolation from these experiments indicates that less than 1 ml of DDFP, in emulsion-form, could provide for the resting oxygen consumption of an adult person. This suggests various therapeutic uses of the emulsion.

Medical treatment of retinal vein occlusions

The medical treatment of retinal vein occlusion (RVO) is comprised of three main stages: identification and therapy of the detectable risk factors, specific treatment aimed at the occlusive form and treatment of RVO complications. Even though the possible medical management of RVO includes several treatments, the most interesting approaches have been: anticoagulant/antiaggregating agents, troxerutin, corticosteroid, fibrinolytic/thrombolytic agents, and hemodilution. Overall, the medical approach to RVO is still awkward and unsatisfactory. Randomized clinical trials are needed to assess the degree of efficacy of the medical treatment of the specific forms of RVO.

[Effect of controlled hypotension with different drugs combined with acute hypervolemic hemodilution on bleeding volume and gastrointestinal perfusion in nasal endoscopic surgery]

OBJECTIVE

To investigate the effect of controlled hypotension using different drugs on gastrointestinal perfusion and bleeding volume in nasal endoscopic surgery.

METHODS

Thirty ASA class I or II patients scheduled for nasal endoscopic surgery were randomized into three groups, including a routine general anesthesia group (group A) and two controlled hypotension groups (groups B and C). After anesthesia induction, anesthesia was maintained with 1%-2% isoflurane and vecuronium. ECG, mean arterial blood pressure (MAP), heart rate (HR), SpO(2) and PETCO(2) were continuously monitored. TRIP tonometry catheter 14 F was inserted into the stomach and connected to Tonocap (Datex-Ohmeda, Finland ). In groups B and C, hypotension was induced with isoflurane (1%-2%) and sodium nitroprusside (0.3-3 microg.kg(-1).min(-1)), and with isoflurane (1%-2%) and glonoine (0.5-5 microg.kg(-1).min(-1)), respectively, and the MAP was reduced to 50-55 mmHg in 10-15 min. In groups B and C, blood samples were taken for blood gas analysis after anesthesia (T(0)), after acute hypervolemic hemodilution (T(1)), at 30 and 60 min after controlled hypotension (T(2) and T(3)), and 30 min after recovery from hypotension (T(4)). In group A, blood samples were taken at different time points in the perioperative period.

RESULTS

The patients in groups B and C had smaller bleeding volume than those in group A. HR was decreased after moderate acute hypervolemic hemodilution, and increased after controlled hypotension (T(2) and T(3)) in comparison with that at T(1) to a level similar to that at T(0). No significant changes were found in pHi at T(2) and T(3) in comparison with that at T(1) in the three groups.

CONCLUSION

When appropriate measures are taken, induced hypotension at 50-55 mmHg does not necessarily produce disturbance in gastrointestinal perfusion. Induced hypotension with glonoin can decrease the bleeding volume better than sodium nitroprusside in nasal endoscopic surgery.

Blood conservation strategies in pediatric anesthesia

Management of bleeding in the neonate, infant, or child presents its own set of dilemmas and challenges. One of the primary problems is the lack of good scientific evidence regarding the best management strategies for children rather than for adults. The key to success in the predicament is firstly to ensure that the physician has a clear understanding of the underlying normal physiology of the young child's hematologic status. Then by adding knowledge of the abnormal pathology that is being presented, the physician can at least understand what anomalies he or she is facing. Once all the available information concerning the patient's clinical condition and the options available has been well digested, a multidisciplinary approach allows the optimal use of all available resources. Good teamwork, understanding, and communication between all vested parties allows for a synergistic relationship to enhance patient care and give the best available end result.

[Changes of rabbit IL-1 and TNF-alpha, etc cytokines in response to acute normovolemic hemodilution with HAES-balanced solution as diluting agent]

AIM

To observe effect of acute normovolemic hemodilution(ANH) with HAES-balanced solution as diluting agent on levels of cytokines including IL-1, IL-2, IL-6 and TNF-alpha in rabbit serum so as to provide theoretical basis for clinical application.

METHODS

A total of 20 healthy adult rabbits were enrolled in the study and randomly divided into two groups (10 rabbits per group), i.e., control group (Group C) and HAES group (Group H). Under anesthesia of the rabbits, we performed incision of trachea, high-frequency jet ventilation and liberation of femoral artery and femoral veins. Group C was free from hemodilution. Group H was injected with dilution (2-fold of blood letting volume) via femoral veins during blood letting of the femoral artery. 6% HAES-steril plus compound solution of sodium lactate, with crystal/gel ratio of 2:1, blood letting volume = TBV x (Ho-Hf)/Hav. All blood was transfused back 60-120 min after blood letting. Venous blood was collected before blood letting (T0) and 30 min (T1), 60 min (T2), 120 min (T3) and 24 h(T4) after blood letting to detect Hb and Hct and measure level of IL-1, IL-2, IL-6 and TNF-alpha in serum.

RESULTS

In Group H, levels of IL-1, IL-2, IL-6 and TNF-alpha in serum were increased from T1 after ANH, reached peak at T3 but showed decrease at T4, with significant difference compared with Group C at T1, T2, T3 and T4 (P < 0.01) and significant difference compared with those before ANH (P <0.01). In Group C, there was no significant difference upon IL-1, IL-2, IL-6 and TNF-alpha in serum at different time points.

CONCLUSION

ANH with HAES-balanced solution as diluting agent can up-regulate the levels of cytokines IL-1, IL-2, IL-6 and TNF-alpha in rabbit serum. In the meantime, ANH may arouse eustress with low intensity and short action time, which exerts effect of enhancing immune function of the organisms.

[Alternatives to allogenous blood transfusion]

Blood transfusion is usually meant to lower morbidity and mortality rates. Allogenous blood transfusion implies certain risks that can be avoided by autologous blood transfusions techniques including: preoperatory autologous blood donation, acute normovolemic hemodilution, intraoperatory and postoperatory blood salvage. Preoperatory blood donation and acute normovolemic hemodilution are used for planned interventions with an estimated blood loss higher than 20% of blood volume. These methods imply Erythropoietin and iron treatment. Intraoperatory and postoperatory blood salvage is performed by personnel trained in blood donation, handling and storage. Autologous blood transfusions are used for certain surgical procedures that commonly require transfusions: orthopedic surgery, radical prostatectomy, cardiovascular surgery, organ transplantation. An alternative to allogenous blood transfusion is the use of artificial oxygen transporters: human or animal hemoglobin solutions or pefluorocarbonate solutions. These solutions do not require cross reactions, do not carry diseases and are generally well tolerated and easily stored in the operating room, ambulance and other transport means. They have however a slight degree of toxicity.

Optimizing circuit design using a remote-mounted perfusion system

There is a considerable amount of literature published on the detrimental effects of banked blood exposure in cardiac surgery. Likewise, in an effort to minimize blood exposure, many of these articles involve modifications to the heart-lung machine or its components to reduce priming volumes, therefore decreasing the need for banked blood administration caused by hemodilution. In this study, using Terumo's System 1 Advanced Heart-Lung machine, all the pump heads were remotely mounted off the pump base closer to the patient and to all the pump components. For example, cardioplegia, ultrafiltration, and vent and cardiotomy lines are now close to the oxygenator and to the patient, minimizing any excess tubing length. Cardiopulmonary bypass (CPB) blood use and priming volumes were compared before and after changing from a fixed perfusion system to a remote-mounted perfusion system using the same disposables and protocols. The mean differences of pump prime and CPB blood use were compared in four weight classes. In the 8- to 12-kg class, blood use was reduced from 1.84 +/- 0.55 to 1.10 +/- 0.36 units. Priming volume was reduced from 751.2 +/- 68.4 to 360.4 +/- 51.7 mL. In the 13- to 20-kg class, blood use was reduced from 1.80 +/- 0.42 to 1.04 +/- 0.28 units. Priming volume was reduced from 829.6 +/- 69.6 to 476. +/- 81.4 mL. In the 21- to 40-kg class, blood use was reduced from 1.60 +/- 0.57 to 0.92 +/- 0.49 units. Priming volume was reduced from 994.0 +/- 137.2 to 713.6 +/- 121.8 mL. In the 41+-kg class, blood use was reduced from 1.62 +/- 0.88 to 0.42 +/- 0.54 units. Priming volume reduced from 1306.3 +/- 112.9 to 875.5 +/- 96.6 mL. In conclusion, using a remote-mounted perfusion system resulted in reducing priming volumes and also significantly decreased the need for banked blood, subsequently saving the patient excessive exposure to banked blood.

[Acute normovolemic hemodilution to reduce allogenic blood transfusion in patients undergoing radical cystectomy]

BACKGROUND

Allogenic blood transfusion is associated with a number of well-recognized risks and complications. We report here acute normovolemic hemodilution (ANH) to reduce allogenic blood transfusion during radical cystectomy.

METHODS

Forty five patients (hematocrit > 35%, ASA status I-II) undergoing elective open radical cystectomy were investigated retrospectively by dividing into two groups, namely ANH group (group H; n=25), and control group (group C; n=20). After induction of general anesthesia combined with epidural anesthesia, autologous whole blood (800-1600ml) is collected in a series of collection bags (group H). When hemoglobin level dropped below the trigger (hemoglobin 7-8 g x dl(-1)) during surgery, allogenic blood transfusion (group C) and/or autologous blood transfusion (group H) were given.

RESULTS

No differences in intraoperative blood loss and urine volume between the two groups were observed. Nine patients in group C made use of allogenic blood transfusion (mean 570 ml). In contrast, no patients were given allogenic blood in group H. Two weeks after the operation, there was no difference in hemoglobin concentrations between the two groups and no serious complications occurred in all the patients studied.

CONCLUSIONS

ANH may be effective in reducing the necessity of allogenic blood transfusion during radical cystectomy with a relatively large surgical blood loss.

Interventions for acute non-arteritic central retinal artery occlusion

BACKGROUND

Acute central retinal artery occlusion (CRAO) occurs as a sudden interruption of the blood supply to the retina and results in an almost complete loss of vision in the affected eye. There is no generally agreed treatment regimen although a number of therapeutic interventions have been proposed.

OBJECTIVES

The objective of this review was to examine the effects of treatments used for acute non-arteritic CRAO.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library, Issue 3, 2008), MEDLINE (January 1966 to September 2008), EMBASE (January 1980 to September 2008) and the reference lists of relevant papers.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) only in which one treatment aimed to re-establish blood supply to the retina in people with acute CRAO was compared to another treatment.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the search results for relevant trials. Discrepancies were resolved by discussion.

MAIN RESULTS

We found two RCTs that met our inclusion criteria.

AUTHORS' CONCLUSIONS

The included studies in this review were small and from single centres. Neither study was completely clear about it's method of treatment allocation. One study described the use of pentoxifylline tablets (three 600 mg tablets daily) and the other the use of enhanced external counterpulsation (EECP) combined with haemodilution. Both studies indicated improved retinal perfusion in the non-control group but neither showed an improvement in vision. Large, well-designed RCTs are still required to establish the most effective treatment for acute CRAO. These studies should be looking at factors important to the patient i.e. improved vision with acceptable risk/side-effects.

Adjuncts to liver surgery: is acute normovolemic hemodilution useful for major hepatic resections?

For patients undergoing major hepatic resection, acute normovolemic hemodilution is a safe technique that effectively reduces allogeneic red blood cell transfusions. In the recent prospective randomized controlled trial completed at MSKCC, there was no difference in the extent of resection, intraoperative blood loss, operative time, incidence and grade of complications, or length of hospital stay between patients who underwent ANH versus standardintraoperative management. Although ANH does reduce the rate o f allogeneic red blood cell transfusions in patients undergoing major hepatectomy, its benefit is particularly pronounced in patients who have significant operative blood loss (i.e., >800 mL). In these patients, the benefit of ANH extends also to the transfusion of FFP. Thus, ANH should be considered for routine use in patients undergoing major hepatectomy who have an expected considerable blood loss. However, given the relatively low transfusion rate overall, future efforts should be directed at preoperatively identifying patients most likely to benefit from ANH.

The impact of fluid restriction policy in reducing the use of red blood cells in cardiac surgery

Hemodilution contributes significantly to transfusion requirements in patients undergoing CABG under CPB. We hypothesised that restriction of parenteral fluids in comparison to a liberal fluid administration policy leads to less use of packed red cells in CABG operations supported by cell salvage. After consent and approval, 130 patients operated under equal conditions were assigned prospectively and randomly either for a restrictive protocol for intravenous fluid administration (group A, 65 pts) or not (group B, 65 pts). Transfusion guidelines were common for the two groups. The volumes of intravenous fluids, priming, "extra" volume on pump and cardioplegic solution and the volume of urine were recorded. Net erythrocyte volume loss was calculated. The number of the transfused PRC was analyzed as a continuous variable. "Transfusion" was analyzed as a categorical characteristic. Significant difference existed between groups for the fluids administered intravenously until the initiation of CPB and for fluid balance after CPB. Intraoperatively transfused units were significantly lower in A (0.32 +/- 0.77 vs 1.26 +/- 1.05 u/per pt; p<0.0001). Transfused patients were also significantly lower in A (11/65 vs 44/65; p<0.0001). In both groups, the values of hematocrit were statistically decreased. The greatest difference compared to the preoperative values was observed after CPB (from 40.8 +/- 4.2 to 21.9 +/- 3.6 for A, and from 40.2 +/- 3.7 to 19.7 +/- 3.3 for B ; p<0.0001 for both). For these lowest values, significant difference existed between groups (p<0,001) while the difference in the hematocrit values to the end of operation was insignificant. Transfusion in ICU showed no significant difference among groups. Hours of mechanical ventilation in ICU were ranging from 5 to 29 (mean = 10.0, median = 9) for A and from 5 to 42 (mean = 14.8, median = 10) for B. Length of stay in ICU in nights for group A was ranging from 1 to 10 (mean = 2.7, median = 2) and for group B was ranging from 1 to 6 (mean = 3.5, median = 2). In conclusion, reduction of transfusions in CABG operations is feasible when a restrictive protocol for intravenous fluids is applied.

Perioperative blood management in total hip arthroplasty

Blood management during total hip arthroplasty is a critical component of successful patient care, and an overall strategy is necessary. Multiple options for blood management are available, including the use of predeposited autologous blood, perioperative blood salvage, hemodilution techniques, erythropoietic agents, hemostatic agents, and allogeneic blood. Rather than relying on automatic so-called transfusion triggers, the surgeon should identify patient-specific risk factors such as the anticipated difficulty of the procedure, preoperative hemoglobin level, comorbidities, and a plan for blood management.

[Enhancement of coagulation caused by transfusion of artificial plasma-replacement solutions]

AIM

To investigate hemostasis disorders caused by massive blood transfusions of artificial plasma replacing solutions (PRS).

MATERIAL AND METHODS

Two groups of patients were examined: 7 healthy volunteers without blood loss (group 1) and 11 healthy donors of bone marrow with intraoperative blood loss 1-2 l (group 2). Five patients of group 1 received transfusion of 12 ml/kg hydroxyethyl starch (HES) 130/0.4, two patients of group 1 received transfusion of modified gelatine solution (gelofusin). All of them received infusions (1-1.5 l) of crystalloid PRS (1-2 l) and infusion of one of colloid PRS (6-HES, 5--gelofusin). Estimated hemodilution in group 1 was 1.17 +/- 0.01 times, in group 2 it varied from 1.3 to 2.7 times (mean 1.78 +/- 0.4 times). Hemostasis was studied by clot growth rate (for groups 1 and 2), endogenic thrombin potential and parameters of thromboelastography (for group 2) in plasm samples obtained before, 2.24 and 48 hours after infusion of colloid PRS.

RESULTS

For both groups spatial clot growth rate 2 hours after hemodilution was high. Then it fell and reached baseline level 48 hours after PRS infusion. Endogenic thrombin potential and thromboelastography data (for group 2) changed by the same pattern. A hypercoagulation effect of gelofusin on parameters of thromboelastography and clot growth rate was higher than of HES 130/04.

CONCLUSION

Moderate hemodilution with PRS in vivo causes hypercoagulation which persisted longer than volemic effect of PRS.

[Clinical observation of acute hypervolemic hemodilution in scoliosis surgery on children]

OBJECTIVE

To evaluate the clinical efficacy and safety of acute hypervolemic hemodilution (AHH) in posterior spinal fusion surgery in children.

METHODS

36 children with scoliosis ASA I approximately II, receive of posterior spinal fusion, were randomly divided into 2 equal groups: AHH group, transfused with hydroxyethyl starch 130/0.4 and sodium chloride (Voluven) 12 ml/kg at the speed of 0.3 approximately 0.4 mlxkg(-1)xmin(-1) (for 30 approximately 40 min) through internal jugular vein before operation so as to keep the hemodilution (Hb) status during operation, and control (CNT) group. During operation when the Hb was <80 g/L or the hematocrit was < 25% blood transfusion was conducted to maintain the Hct > 25%.

RESULTS

There was no significant difference in intra-operative blood loss between these 2 groups. The Hb one day after operation of the AHH group was (89 +/- 12) g/L, significantly lower than that immediately after operation [(98 +/- 10) g/L, P < 0.05]. The Hb one day after operation of the CNT group was (92 +/- 22) g/L, significantly lower than that immediately after operation [(94 +/- 13) g/L, P < 0.05]. However, there were not significant differences in the Hb values between the AHH and CNT groups (all P > 0.05). Both groups received intra-operative transfusion during operation. The amount of transfused red blood cells and fresh frozen plasma of the AHH group were (18 +/- 4) ml/kg and (3.5 +/- 1.1) ml/kg respectively, both significantly lower than those of the CNT group [(28 +/- 11) and (5.8 +/- 1.8) ml/kg respectively, both P < 0.05].

CONCLUSION

Able to reduce intra-operative blood transfusion and medical expense, AHH can be used safely and effectively in posterior spine fusion in children.

Influence of acute normovolaemic haemodilution on bispectral index monitoring and propofol dose requirements

BACKGROUND

Numerous medical and physiological conditions that might alter electroencephalography (EEG), such as hypoglycaemia, hypothermia or hypovolaemia, were shown to result in the bispectral Index (BIS) indicating an incorrect hypnotic state. Recently, acute normovolaemic haemodilution (ANH) was shown to be associated with significant impairment of cognitive functions that could alter EEG and consequently BIS monitoring, an EEG derived parameter.

METHODS

In a randomised clinical study, we assessed the effect of ANH on BIS monitoring before induction and after propofol target controlled infusion (TCI) anaesthesia in 45 unmedicated patients randomly allocated to ANH with oxygen insufflation (oxygen group), ANH with air insufflation (air group), or control group.

RESULTS

With ANH, mean BIS values briefly declined in the oxygen group (82+/-4) and air group (84+/-3) before returning to baseline values. The loss of consciousness time was significantly shorter, with fewer propofol TCI dose requirements, and BIS was significantly higher in the oxygen group (1.3+/-0.5 min, 2.41+/-0.15 microg/ml, 73+/-7) and air group (1.2+/-0.6 min, 2.44+/-0.17 microg/ml, 75+/-5), compared with the control group (1.7+/-0.4 min, 2.75+/-0.17 microg/ml, 61+/-5), respectively. Whereas, there was no significant difference in BIS values between the oxygen group (38+/-7), air group (36+/-5) and control group (40+/-6) at propofol TCI 4 microg/ml anaesthesia maintenance.

CONCLUSIONS

BIS values briefly declined with ANH before returning to baseline values before anaesthesia induction. Despite transient ANH enhancement of propofol effect during induction, there was no significant difference in BIS values with or without ANH during propofol maintenance of anaesthesia.

Acute normovolaemic haemodilution with crystalloids in coronary artery bypass graft surgery: a preliminary survey of haemostatic markers

INTRODUCTION

Acute normovolaemic haemodilution (ANH) is a safe and cost-effective blood conservation strategy in procedures with great blood loss. It eliminates the risk of administrative errors and also contaminations that may occur whenever banked blood is used. Classically, haemodilution is regarded as causing coagulopathy. This study was designed to determine the effect of crystalloids on measured coagulation values and perioperative blood loss following ANH in patients undergoing elective coronary revascularization.

METHODS

Following a prospective case-control study one hundred candidates for CABG (50 cases in the ANH group and 50 in the control group) were included. Blood samples for coagulation testing haematocrit and platelet levels were collected before ANH, after cardiopulmonary bypass (CPB), and upon arrival at the intensive care unit (ICU). Differences were considered statistically significant with P values < 0.05.

RESULT

There was no statistically significant difference between chest tube drainage in the two groups. The number of patients using PRBC (packed red blood cell) or FFP (fresh frozen plasma) was significantly higher in the control group in comparison to the ANH group (P < 0.05). The PT increased significantly after arrival in the ICU in both groups (P < 0.001) but there was no between-group difference (P = 0.22). aPTT not only did not change significantly in the ICU relative to the baseline pre ANH values in both groups (P > 0.05) but also did not show any between-group difference (P = 0.69). There was no statistically significant difference in the aCT of the control and the ANH group after arrival to the ICU (P = 0.09). Hct and Plt decreased significantly in both groups after CPB and arrival at ICU.

CONCLUSION

ANH reduced the need for PRBC and FFP by 58% and 74%, respectively. Regarding the increase in PT and decrease in Plt count, we concluded that performing ANH with saline solution (SS) in patients undergoing CABG surgery may cause a non-clinically significant change in coagulation state.

[Efficiency of using gelofusine and voluven in acute normovolemic hemodilution during cardiosurgical interventions]

The aim of the study was to assess the use of gelofusine and voluven for acute normovolemic hemodilution at cardiac surgery under extracorporeal circulation (EC). Sixty-seven patients with coronary heart disease were examined. Heart rate, total peripheral vascular resistance, pulmonary pressure, pulmonary artery wedge pressure, oxygen delivery and consumption, central venous pressure, arteriovenous oxygen difference, oncotic pressure, and postoperative clinical course were studied. No significant group differences were found in indices, other than arteriovenous oxygen difference, after acute normovolemic hemodilution and in central venous pressure following 6 hours of EC termination. The administration of gelofusine caused a more steady-state oxygen-transport function of the circulatory system. The use of the agent for acute normovolemic hemodilution at cardiac surgery under EC is more economically justified than that of volumen.