The effect of albumin priming solution on platelet activation during experimental long-term perfusion

Management of priming fluids in cardiopulmonary bypass for adult cardiac surgery: network meta-analysis

BACKGROUND

Cardiopulmonary bypass (CPB) is frequently employed for cardiac surgery, and selecting a suitable priming fluid is a prerequisite for CPB. Currently, the commonly used priming fluids in clinics are classified as crystalloids and colloids, including balanced crystalloids, albumin, dextran, gelatin and hydroxyethyl starch (HES). This network meta-analysis compared the effects of eight fluids used during CPB in adults to determine optimal priming fluid during CPB surgery.

METHODS

Randomised controlled trials assessing priming fluids for CPB in adult cardiac surgery published before 13 April 2023 were searched across Ovid MEDLINE(R) ALL, OVID EMbase, and Cochrane Central Register of Controlled Trials. Various priming fluids were classified into eight categories, including balanced crystalloids, 0.9% NaCl, iso-oncotic human albumin, hyperoncotic human albumin, HES with molecular weight 130k, HES with molecular weight 200k, gelatin and dextran.

RESULTS

The NMA of platelet counts revealed no significant differences in any result. In direct comparison results, only the comparison of HES with molecular weight 130k vs. gelatin (standard mean difference = -0.40, 95% confidence interval [95%CI: -0.63, -0.16) revealed a significant difference. According to the SUCRA, balanced crystalloids had the highest platelet count, followed by gelatin, and HES with a molecular weight of 130k had the lowest platelet, followed by HES with a molecular weight of 200k.

CONCLUSION

Patients using dextran have a low mortality rate and a short mean CPB time, the use of balanced crystalloids is beneficial in terms of platelet count, and HES with molecular weight 130k is beneficial for postoperative urine volume at 24h. However, all priming fluids have pros and cons quite, and the optimal choice of priming fluids remains unsupported by current evidences. When performing CPB surgery, the type of priming fluid should be selected according to the actual situation in CPB for adult cardiac surgery.

The comparison of albumin and 6% hydroxyethyl starches (130/0.4) in cardiac surgery: a meta-analysis of randomized controlled clinical trials

Background

Fluid administration is a key tool in the maintenance of normovolemia in patients with cardiac surgery. The trials that evaluated the safety of 6% hydroxyethyl starch (HES) 130/0.4 in cardiac surgical patients were inconsistent. It is necessary to compare the efficacy and safety of albumin and 6% HES (130/0.4).

Method

We searched for the randomized controlled clinical trials that compared human albumin with 6% HES (130/0.4) in cardiac surgery in PubMed, Cochrane, and Embase.

Results

Ten studies involved a total of 1567 patients were included in our meta-analysis. For the efficiency, there was no difference in total volume of infusion between compared groups [P = 0.64, Fixed Effect Model (FEM): standardized mean difference (SMD) = 0.04, 95% confidence interval (CI) (− 0.12, 0.20)]. As for safety, the albumin show more risk than hydroxyethyl starch 130/0.4 in blood loss [P = 0.02, FEM: SMD: 0.22, 95% CI (0.03, 0.41)]. There was no difference in the frequency of transfusions (P = 0.20, RR = 1.11; 95% CI (0.95, 1.27)) between the two groups. No difference was observed for the days in intensive care unit [P = 0.05, FEM: SMD = − 0.18, 95% CI (− 0.36, 0.00)], and the days in hospital [P = 0.32, FEM: SMD = − 0.11, 95% CI (− 0.32, 0.10)]. Furthermore, both the incidence of AKI, RRT, and mortality were comparable in the two groups.

Conclusion

This study provided evidence that the 6% HES (130/0.4) might be the substitute for HA, which reduced the economic burden for patients with cardiac surgery. However, the effect of 6% HES (130/0.4) and HA on AKI still needs to be further studied.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-021-01340-x.

Blood Loss and Related Laboratory Changes after Single-Event Multilevel Surgery and Hip Reconstructive Surgery in Patients with Cerebral Palsy

Backgroud

Single-event multilevel surgery (SEMLS) and hip reconstructive surgery (HRS) often cause intraoperative bleeding, consequently increasing the probability of transfusion and postoperative laboratory changes. Therefore, it is important to assess risk factors to predict the amount of blood loss. This study aimed to evaluate blood loss, its influencing factors, and the related laboratory changes during SEMLS and HRS in patients with cerebral palsy (CP).

Methods

We retrospectively examined consecutive CP patients who underwent SEMLS and HRS. Surrogate markers of blood loss, including preoperative and postoperative hemoglobin (Hb), hematocrit, and changes in Hb concentration, were assessed. Albumin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatine levels were also analyzed for related laboratory changes. Risk factors were analyzed using multiple regression and logistic regression models.

Results

The overall cohort comprised 1,188 patients. Of them, 1,007 and 181 underwent SEMLS and HRS, respectively. Furthermore, 72 of 181 patients underwent a concomitant Dega osteotomy. The regression model showed that low preoperative Hb concentration (p < 0.001), high albumin level (p = 0.007), low body mass index (BMI) (p = 0.002), and bilateral HRS (p < 0.001) were significant risk factors of postoperative anemia. Valproate medication was associated with Hb drop, and the risk factors for Hb level < 8 g/dL on postoperative day 2 were bilateral HRS and Dega osteotomy in the HRS subgroup. In total, 21.6% had elevated AST levels on postoperative day 2, and bilateral HRS (p < 0.001), Gross Motor Function Classification System (GMFCS) level V (p = 0.041), Dega osteotomy (p < 0.001), and high preoperative AST level (p < 0.001) increased the risk of AST elevation.

Conclusions

We have summarized the estimated blood loss and related laboratory changes after SEMLS and HRS in patients with CP and identified the risk factors. Clinical guidelines should be accordingly developed to include assessment of these risk factors and their impact in the outcomes of CP patients undergoing SEMLS and HRS.

Hematologic concerns in extracorporeal membrane oxygenation

This ISTH "State of the Art" review aims to critically evaluate the hematologic considerations and complications in extracorporeal membrane oxygenation (ECMO). ECMO is experiencing a rapid increase in clinical use, but many questions remain unanswered. The existing literature does not address or explicitly state many pertinent details that may influence hematologic complications and, ultimately, patient outcomes. This review aims to broadly introduce modern ECMO practices, circuit designs, circuit materials, hematologic complications, transfusion-related considerations, age- and size-related differences, and considerations for choosing outcome measures. Relevant studies from the 2019 ISTH Congress in Melbourne, which further advanced our understanding of these processes, will also be highlighted.

Fresh Frozen Plasma versus Crystalloid Priming of Cardiopulmonary Bypass Circuit in Pediatric Surgery

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

In congenital cardiac surgery, priming cardiopulmonary bypass (CPB) with fresh frozen plasma (FFP) is performed to prevent coagulation abnormalities. The hypothesis was that CPB priming with crystalloids would be different compared with FFP in terms of bleeding and/or need for blood product transfusion.

Methods

In this parallel-arm double-blinded study, patients weighing between 7 and 15 kg were randomly assigned to a CPB priming with 15 ml · kg−1 PlasmaLyte or 15 ml · kg−1 FFP in addition to a predefined amount of packed red blood cells used in all patients. The decision to transfuse was clinical and guided by point-of-care tests. The primary endpoints included postoperative bleeding tracked by chest tubes, number of patients transfused with any additional blood products, and the total number of additional blood products administered intra- and postoperatively. The postoperative period included the first 6 h after intensive care unit arrival.

Results

Respectively, 30 and 29 patients in the FFP and in the crystalloid group were analyzed in an intention-to-treat basis. Median postoperative blood loss was 7.1 ml · kg−1 (5.1, 9.4) in the FFP group and 5.7 ml · kg−1 (3.8, 8.5) in the crystalloid group (P = 0.219); difference (95% CI): 1.2 (−0.7 to 3.2). The proportion of patients additionally transfused was 26.7% (8 of 30) and 37.9% (11 of 29) in the FFP and the crystalloid groups, respectively (P = 0.355; odds ratio [95% CI], 1.7 [0.6 to 5.1]). The median number of any blood products transfused in addition to priming was 0 (0, 1) and 0 (0, 2) in the FFP and crystalloid groups, respectively (P = 0.254; difference [95% CI], 0 [0 to 0]). There were no study-related adverse events.

Conclusions

The results demonstrate that in infants and children, priming CPB with crystalloids does not result in a different risk of postoperative bleeding and need for transfusion of allogeneic blood products.

In Vitro Thrombogenicity Testing of Biomaterials

The short- and long-term thrombogenicity of implant materials is still unpredictable, which is a significant challenge for the treatment of cardiovascular diseases. A knowledge-based approach for implementing biofunctions in materials requires a detailed understanding of the medical device in the biological system. In particular, the interplay between material and blood components/cells as well as standardized and commonly acknowledged in vitro test methods allowing a reproducible categorization of the material thrombogenicity requires further attention. Here, the status of in vitro thrombogenicity testing methods for biomaterials is reviewed, particularly taking in view the preparation of test materials and references, the selection and characterization of donors and blood samples, the prerequisites for reproducible approaches and applied test systems. Recent joint approaches in finding common standards for a reproducible testing are summarized and perspectives for a more disease oriented in vitro thrombogenicity testing are discussed.

Experimental effect of different dilutions of blood with human plasma protein fraction and large dose factor one on blood coagulation and chemistry in vitro

Background and Aims:

Human plasma protein fraction 5% (PPF5%) is an albumin-based colloid used to expand the plasma volume during volume deficiency. The current basic medical experimental study assessed in vitro coagulation of PPF5% solution and its effects on blood coagulation and chemistry.

Methods:

The study involved 20 volunteers, and each volunteer donated 20–50 ml of fresh blood. Three dilutions of blood with PPF5% dilutions were prepared (30, 50, and 70%). The fibrinogen dose required to correct coagulation in the 50% diluted samples was assessed (two doses used). The thromboelastogram (TEG) measured the haemostatic parameters (fibrinogen level, initiation of coagulation [R time], kinetics [K], acceleration of coagulation [α angle], maximum amplitude [MA] and coagulation index [CI]), and the ABL gas analyser measured the blood chemistry changes.

Results:

All dilutions showed significant TEG and blood chemistry changes when compared to controls. The two doses of fibrinogen corrected the clot formation speed with no significant difference in speed between the two doses. Acidosis measured by the strong ion gap (SID) and pH were significant for all dilutions when compared with the baseline. The 30% dilution remained within the lower normal acceptable value while 50% dilution was beyond the critical normal values.

Conclusion:

In vitro PPF5% to replace blood loss up to 50% dilution did not have significant coagulation and blood chemistry effects while coagulopathy should be expected in extreme dilutions (70%). Fibrinogen in a dose equivalent to 4 gm/70 kg adult improved clot strength at 50% dilution.

Impact of Albumin on Coagulation Competence and Hemorrhage During Major Surgery: A Randomized Controlled Trial

For patients exposed to a massive blood loss during surgery, maintained coagulation competence is important. It is less obvious whether coagulation competence influences bleeding during elective surgery where patients are exposed to infusion of a crystalloid or a colloid. This randomized controlled trial evaluates whether administration of 5% human albumin (HA) or lactated Ringer solution (LR) affects coagulation competence and in turn blood loss during cystectomy due to bladder cancer. Forty patients undergoing radical cystectomy were included to receive either 5% HA (n = 20) or LR (n = 20). Nineteen patients were analyzed in the HA group and 20 patients in the lactated Ringer group. Blinded determination of the blood loss was similar in the 2 groups of patients: 1658 (800-3300) mL with the use of HA and 1472 (700-4330) mL in the lactated Ringer group (P = 0.45). Yet, by thrombelastography (TEG) evaluated coagulation competence, albumin affected clot growth (TEG-angle 69 ± 5 vs 74° ± 3°, P < 0.01) and strength (TEG-MA: 59 ± 6 vs 67 ± 6 mm, P < 0.001) more than LR. Furthermore, by multivariate linear regression analyses reduced TEG-MA was independently associated with the blood loss (P = 0.042) while administration of albumin was related to the changes in TEG-MA (P = 0.029), aPPT (P < 0.022), and INR (P < 0.033). This randomized controlled trial demonstrates that administration of HA does not affect the blood loss as compared to infusion of LR. Also the use of HA did not affect the need for blood transfusion, the incidence of postoperative complications, or the hospital in-stay. Yet, albumin decreases coagulation competence during major surgery and the blood loss is related to TEG-MA rather than to plasma coagulation variables.

Effect of 6% hydroxyethyl starch 130/0.4 as a priming solution on coagulation and inflammation following complex heart surgery

PURPOSE

Prolonged duration of cardiopulmonary bypass aggravates the degree of inflammation and coagulopathy. We investigated the influence of 6% hydroxyethyl starch (HES) 130/0.4 on coagulation and inflammation compared with albumin when used for both cardiopulmonary bypass priming and perioperative fluid therapy in patients undergoing complex valvular heart surgery.

MATERIALS AND METHODS

Fifty four patients were randomly allocated into albumin-HES, albumin-nonHES, and HES-HES groups. The cardiopulmonary bypass circuit was primed with 5% albumin in the albumin-HES and albumin-nonHES group, and with HES in the HES-HES group. As perioperative fluid, only plasmalyte was used in the albumin-nonHES group whereas HES was used up to 20 mL/kg in the albumin-HES and albumin-HES group. Serial assessments of coagulation profiles using the rotational thromboelastometry and inflammatory markers (tissue necrosis factor-α, interleukin-6, and interleukin-8) were performed.

RESULTS

Patients' characteristics and the duration of cardiopulmonary bypass (albumin-HES; 137±34 min, HES-HES; 136±47 min, albumin-nonHES; 132±39 min) were all similar among the groups. Postoperative coagulation profiles demonstrated sporadic increases in clot formation time and coagulation time, without any differences in the actual amount of perioperative bleeding and transfusion requirements among the groups. Also, inflammatory markers showed significant activation after cardiopulmonary bypass without any differences among the groups.

CONCLUSION

Even in the presence of prolonged duration of cardiopulmonary bypass, HES seemed to yield similar influence on the ensuing coagulopathy and inflammatory response when used for priming and perioperative fluid therapy following complex valvular heart surgery compared with conventional fluid regimen including albumin and plasmalyte.

Effects of albumin and synthetic polypeptide-coated oxygenators on IL-1, IL-2, IL-6, and IL-10 in open heart surgery

BACKGROUND

In this study, we have tried to demonstrate the effects of coating style used in oxygenators on various hematologic and clinical parameters.

MATERIALS AND METHODS

Twenty-seven patients were included in the study, who had undergone operations because of elective coronary artery disease. Albumin-coated oxygenator was used in Group I. In Group II, a synthetic polypeptide-coated oxygenator was used. C1-inhib (complement), C3c, C4, interleukins (IL-1β, IL2, IL-6, IL-10), and tumor necrosis factor alpha (TNF-α) levels were examined at four different time intervals. Hemoglobin, hematocrit, leukocyte and platelet counts, drainage, and transfused blood volumes were analyzed.

RESULTS

Albumin levels were significantly lower in Group I than those in Group II 5 minutes after the removal of the cross-clamp. Twenty-four hours after the surgery, Group I patients also had a significantly higher white blood cell count compared to Group II patients. TNF-α levels in Group I were always expressed in considerably higher amounts than those in Group II. IL-6 levels were significantly higher in Group I, but IL-10 levels were observed to be higher in Group II (p < 0.05).

CONCLUSION

Synthetic polypeptide-coated advanced technology, which employed oxygenators, had an important attenuator effect on acute phase reactants and also on the inflammatory response.

Comparison of the effects of albumin 5%, hydroxyethyl starch 130/0.4 6%, and Ringer's lactate on blood loss and coagulation after cardiac surgery

BACKGROUND

Infusion of 5% human albumin (HA) and 6% hydroxyethyl starch 130/0.4 (HES) during cardiac surgery expand circulating volume to a greater extent than crystalloids and would be suitable for a restrictive fluid therapy regimen. However, HA and HES may affect blood coagulation and could contribute to increased transfusion requirements.

METHODS

We randomly assigned 240 patients undergoing elective cardiac surgery to receive up to 50 ml kg(-1) day(-1) of either HA, HES, or Ringer's lactate (RL) as the main infusion fluid perioperatively. Study solutions were supplied in identical bottles dressed in opaque covers. The primary outcome was chest tube drainage over 24 h. Blood transfusions, thromboelastometry variables, perioperative fluid balance, renal function, mortality, intensive care unit, and hospital stay were also assessed.

RESULTS

The median cumulative blood loss was not different between the groups (HA: 835, HES: 700, and RL: 670 ml). However, 35% of RL patients required blood products, compared with 62% (HA) and 64% (HES group; P=0.0003). Significantly, more study solution had to be administered in the RL group compared with the colloid groups. Total perioperative fluid balance was least positive in the HA group [6.2 (2.5) litre] compared with the HES [7.4 (3.0) litre] and RL [8.3 (2.8) litre] groups (P<0.0001). Both colloids affected clot formation and clot strength and caused slight increases in serum creatinine.

CONCLUSIONS

Despite equal blood loss from chest drains, both colloids interfered with blood coagulation and produced greater haemodilution, which was associated with more transfusion of blood products compared with crystalloid use only.

Changes in muscle compartment pressure after cardiopulmonary bypass

PURPOSE

Hemodilution and inflammation lead to edema and increased muscle compartment pressure after cardiac surgery. The aim of this study was to find whether muscle compartment pressure was affected by the addition of albumin and mannitol to the pump prime, heparin coating or leukocyte depletion. Additionally, we studied the relationship between intraocular pressure and lower leg muscle compartment pressure. Edema during and following cardiac surgery is due to hemodynamic, osmotic and inflammatory changes, according to Starling's Law. We attempted to influence the osmotic balance and reduce the inflammatory response in order to reduce the edema.

METHODS

Thirty-six patients who underwent cardiac surgery were randomly allocated into four groups. Group A received albumin and mannitol into the pump prime. Group B had an, heparin-coated perfusion system, Group C had a leukocyte-depletion arterial line filter and Group D was the control group, where intraocular pressure was also measured.

RESULTS

Lower leg muscle compartment pressure increased significantly during and after cardiac surgery in all groups, but this increase was significantly less in Group A than in the control group 24 h after surgery. No correlation was found between muscular compartment pressure and intraocular pressure. The intraocular pressure profile is different from the muscular compartment pressure and recovers much faster.

CONCLUSION

Lower leg muscle compartment pressure and intraocular pressure behave differently during and after cardiac surgery. Albumin and mannitol added to the pump prime decreases muscle compartment pressure after cardiac surgery.

In vitro hemocompatibility of albumin-heparin multilayer coatings on polyethersulfone prepared by the layer-by-layer technique

Polyethersulfone foils (PES)--a unique material for blood purification membranes--were coated with a multilayer assembly of heparin (unfractionated or high anticoagulant activity fraction heparin) and albumin (albumin-heparin coatings), or with a multilayer of albumin (albumin coating), using the layer-by-layer technique. The coatings combine advantages of albumin (reduction of nonspecific interactions) and heparin (specific interactions with blood coagulation proteins). The differences between the two heparins, while significant for their biological activity, had only a minor effect on the multilayer assembly with albumin monitored in situ by reflection infrared spectroscopy (FTIR MIRS). Uncoated as well as modified PES surfaces were evaluated using an in vitro assay with freshly drawn, slightly heparinized (1.5 IU heparin/mL) human whole blood. The blood was circulated with a roller pump over the sample surfaces in shear flow across rectangular slit channels ( app. 6 mL/min and 120 s(-1)) for 1.5 h at 37 degrees C. All coatings effectively reduced platelet adhesion and activation according to the PF4 release. The activation of coagulation evaluated as TAT generation was significantly lowered for the coating composed of albumin and high activity heparin. A further beneficial effect of the heparin containing coatings was reduced complement activation as determined by different complement fragments.

Albumin versus crystalloid for pump priming in cardiac surgery: Meta-analysis of controlled trials

OBJECTIVES

To determine the effects of pump priming fluid choice on platelets, fluid balance, and clinical outcomes.

DESIGN

Meta-analysis of controlled clinical trials. Primary endpoints were platelet counts, colloid oncotic pressure, on-bypass fluid balance, postoperative weight gain, and colloid usage.

SETTING

Cardiac surgery with cardiopulmonary bypass.

PATIENTS

Adult and pediatric patients undergoing cardiac surgery, including coronary artery bypass grafting, valve procedures, and correction of congenital cardiac anomalies.

INTERVENTIONS

Extracorporeal circuit priming with either albumin or crystalloid.

MEASUREMENTS AND RESULTS

The meta-analysis included 21 controlled trials with 1,346 total patients. Albumin prime significantly reduced the on-bypass drop in platelet counts. The pooled weighted mean difference in platelet count drop with albumin versus crystalloid prime was -23.8 x 10(9)/L (confidence interval [CI], -42.8 to -4.7 x 10(9)/L). The colloid oncotic pressure decline was also smaller when albumin rather than crystalloid was used for priming, with a pooled weighted mean difference of -3.6 mm Hg (CI, -4.8 to -2.3 mmHg) during bypass and -2.0 mmHg (CI, -2.9 to -1.1 mmHg) after surgery. Albumin prime correspondingly reduced on-bypass positive fluid balance (-584 mL; CI, -819 to -348 mL) and postoperative weight gain (-1.0 kg; CI, -0.6 to -1.3 kg) compared with crystalloid. Postoperative colloid usage was lower with albumin than crystalloid prime (-612 mL; CI, -983 to -241 mL).

CONCLUSIONS

Albumin prime better preserves platelet counts than crystalloid. Albumin also favorably influences colloid oncotic pressure, on-bypass positive fluid balance, postoperative weight gain, and colloid usage. The clinical significance of these observations merits further investigation.

Is the use of albumin in colloid prime solution of cardiopulmonary bypass circuit justified?

BACKGROUND

Albumin in the priming solution precoats the surface of the cardiopulmonary bypass circuit, supposedly causing delayed adsorption of fibrinogen and reduced activation and adhesion of platelets. This action may result in lower transoxygenator resistance. Because our institution uses a colloidal prime solution (Gelofusine), questions were raised about the value of albumin in the prime solution. We decided to focus on the clinical effects of transoxygenator resistance.

METHODS

Sixty adults undergoing elective cardiac operations were randomly divided into three groups: a group with 20-g albumin (n = 20), a group with 2-g albumin (n = 20), and a group with no albumin (n = 20) in the 1,600-mL colloidal prime. Patients older than 75 years and patients with a preoperative serum albumin level of 30 g/L or less were excluded. The transoxygenator resistance was measured throughout cardiopulmonary bypass. Beta-thromboglobulin levels were used to study contact activation of platelets. Measures of prothrombin F1,2 fragments were used as a marker of thrombin generation. Body surface area, age, preoperative albumin, hematocrit, hemoglobin, fibrinogen, platelet count, and colloid osmotic pressure levels were compared between groups.

RESULTS

Base line characteristics and chosen control measurements were similar for all three populations. When comparing the observed transoxygenator resistance among the three different groups, no significant differences were noted. Prothrombin F1.2 fragments remained low for all the groups without significant differences. In the no-albumin group the level of beta-thromboglobulin appeared to be higher, but the difference was not statistically significant.

CONCLUSIONS

Addition of albumin to prime solution in a cardiopulmonary bypass circuit that already contains colloids does not affect the transoxygenator resistance of the COBE Duo flat sheet oxygenator and does not affect prothrombin F1.2 and beta-thromboglobulin levels. Therefore additional costs for the albumin are not justified. Measurement of transoxygenator resistance is a reliable, simple method to determine the effects of a prime solution on the oxygenator surface in vivo.

Oxygenator thrombosis: an international phenomenon

Oxygenator thrombosis, despite adequate anticoagulation, has become a recent concern amongst perfusionists worldwide. The phenomenon is characterized by a transient increase in oxygenator inlet pressure of up to 900 mmHg about 10-15 min after the institution of cardiopulmonary bypass (CPB). Depending on the size and location of the thrombus, shunting may occur that compromises gas transfer to the extent where oxygenator change-out is necessary. This article presents various case reports and publications, both domestic and international, detailing this phenomenon. Research hypothesizes that it is the activation of platelets that subsequently may cause the deposition of fibrin, yielding thrombus formation; however, the primary etiology of this phenomenon remains unknown. Possible catalysts include bypass techniques, equipment selection, pharmacological agents, prime and the patient. This paper will review all of the above with an emphasis on the often overlooked factor--the patient, as there are certain variables in patient hematology that provoke a hypercoagulable state leading to thrombosis, including blood type, genetics, age, disease state, gender and heparin.