American Society of ExtraCorporeal Technology: Development of Standards and Guidelines for Pediatric and Congenital Perfusion Practice (2019).

The development of standards and guidelines by professional societies offers clinicians guidance toward providing evidence-based care. The ultimate goals of standards and guidelines are to standardize care and improve patient safety and outcomes while also minimizing risk. The American Society of ExtraCorporeal Technology (AmSECT) currently offers perfusionists several clinical resources, primarily the Standards and Guidelines for Perfusion Practice; however, no document exists specific to pediatric perfusion. Historically, the development of a pediatric-specific document has been limited by available scientific evidence due to smaller patient populations, sample sizes, and variable techniques among congenital perfusionists. In the current setting of evolving clinical practices and increasingly complex cardiac operations, a subcommittee of pediatric perfusionists developed the Standards and Guidelines for Pediatric and Congenital Perfusion Practice. The development process included a comprehensive literature review for supporting evidence to justify new recommendations or updates to the existing AmSECT Adult Standards and Guidelines document. Multiple revisions incorporating feedback from the community led to a finalized document accepted by the AmSECT membership and made available electronically in May 2019. The Standards and Guidelines for Pediatric and Congenital Perfusion Practice is an essential tool for pediatric perfusionists and serves as the backbone for institutionally based protocols, promotes improved decision-making, and identifies opportunities for future research and collaboration with other disciplines. The purpose of this manuscript is to summarize the process of development, the content, and recommended utilization of AmSECT's Standards and Guidelines for Pediatric and Congenital Perfusion Practice.

2019 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations.

The International Liaison Committee on Resuscitation has initiated a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation science. This is the third annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. It addresses the most recent published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. This summary addresses the role of cardiac arrest centers and dispatcher-assisted cardiopulmonary resuscitation, the role of extracorporeal cardiopulmonary resuscitation in adults and children, vasopressors in adults, advanced airway interventions in adults and children, targeted temperature management in children after cardiac arrest, initial oxygen concentration during resuscitation of newborns, and interventions for presyncope by first aid providers. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the certainty of the evidence on the basis of the Grading of Recommendations, Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence to Decision Framework Highlights sections. The task forces also listed priority knowledge gaps for further research.

Low-flow assessment of current ECMO/ECCO2R rotary blood pumps and the potential effect on hemocompatibility.

BACKGROUND: Extracorporeal carbon dioxide removal (ECCO2R) uses an extracorporeal circuit to directly remove carbon dioxide from the blood either in lieu of mechanical ventilation or in combination with it. While the potential benefits of the technology are leading to increasing use, there are very real risks associated with it. Several studies demonstrated major bleeding and clotting complications, often associated with hemolysis and poorer outcomes in patients receiving ECCO2R. A better understanding of the risks originating specifically from the rotary blood pump component of the circuit is urgently needed. METHODS: High-resolution computational fluid dynamics was used to calculate the hemodynamics and hemocompatibility of three current rotary blood pumps for various pump flow rates. RESULTS: The hydraulic efficiency dramatically decreases to 5-10% if operating at blood flow rates below 1 L/min, the pump internal flow recirculation rate increases 6-12-fold in these flow ranges, and adverse effects are increased due to multiple exposures to high shear stress. The deleterious consequences include a steep increase in hemolysis and destruction of platelets. CONCLUSIONS: The role of blood pumps in contributing to adverse effects at the lower blood flow rates used during ECCO2R is shown here to be significant. Current rotary blood pumps should be used with caution if operated at blood flow rates below 2 L/min, because of significant and high recirculation, shear stress, and hemolysis. There is a clear and urgent need to design dedicated blood pumps which are optimized for blood flow rates in the range of 0.5-1.5 L/min.

Determinants of the effect of extracorporeal carbon dioxide removal in the SUPERNOVA trial: implications for trial design.

PURPOSE: To describe the variability and determinants of the effect of extracorporeal CO2 removal (ECCO2R) on tidal volume (Vt), driving pressure (ΔP), and mechanical power (PowerRS) and to determine whether highly responsive patients can be identified for the purpose of predictive enrichment in ECCO2R trial design. METHODS: Using data from the SUPERNOVA trial (95 patients with early moderate acute respiratory distress syndrome), the independent effects of alveolar dead space fraction (ADF), respiratory system compliance (Crs), hypoxemia (PaO2/FiO2), and device performance (higher vs lower CO2 extraction) on the magnitude of reduction in Vt, ΔP, and PowerRS permitted by ECCO2R were assessed by linear regression. Predicted and observed changes in ΔP were compared by Bland-Altman analysis. Hypothetical trials of ECCO2R, incorporating predictive enrichment and different target CO2 removal rates, were simulated in the SUPERNOVA study population. RESULTS: Changes in Vt permitted by ECCO2R were independently associated with ADF and device performance but not PaO2/FiO2. Changes in ΔP and PowerRS were independently associated with ADF, Crs, and device performance but not PaO2/FiO2. The change in ΔP predicted from ADF and Crs was moderately correlated with observed change in ΔP (R2 0.32, p < 0.001); limits of agreement between observed and predicted changes in ΔP were ± 3.9 cmH2O. In simulated trials, restricting enrollment to patients with a larger predicted decrease in ΔP enhanced the average reduction in ΔP, increased predicted mortality benefit, and reduced sample size and screening size requirements. The increase in statistical power obtained by restricting enrollment based on predicted ΔP response varied according to device performance as specified by the target CO2 removal rate. CONCLUSIONS: The lung-protective benefits of ECCO2R increase with higher alveolar dead space fraction, lower respiratory system compliance, and higher device performance. ADF and Crs, rather than severity of hypoxemia, should be the primary factors determining whether to enroll patients in clinical trials of ECCO2R.

Feasibility and safety of low-flow extracorporeal CO2 removal managed with a renal replacement platform to enhance lung-protective ventilation of patients with mild-to-moderate ARDS.

BACKGROUND: Extracorporeal carbon-dioxide removal (ECCO2R) might allow ultraprotective mechanical ventilation with lower tidal volume (VT) (< 6 ml/kg predicted body weight), plateau pressure (Pplat) (< 30 cmH2O), and driving pressure to limit ventilator-induced lung injury. This study was undertaken to assess the feasibility and safety of ECCO2R managed with a renal replacement therapy (RRT) platform to enable very low tidal volume ventilation of patients with mild-to-moderate acute respiratory distress syndrome (ARDS). METHODS: Twenty patients with mild (n = 8) or moderate (n = 12) ARDS were included. VT was gradually lowered from 6 to 5, 4.5, and 4 ml/kg, and PEEP adjusted to reach 23 ≤ Pplat ≤ 25 cmH2O. Standalone ECCO2R (no hemofilter associated with the RRT platform) was initiated when arterial PaCO2 increased by > 20% from its initial value. Ventilation parameters (VT, respiratory rate, PEEP), respiratory system compliance, Pplat and driving pressure, arterial blood gases, and ECCO2R-system operational characteristics were collected during at least 24 h of very low tidal volume ventilation. Complications, day-28 mortality, need for adjuvant therapies, and data on weaning off ECCO2R and mechanical ventilation were also recorded. RESULTS: While VT was reduced from 6 to 4 ml/kg and Pplat kept < 25 cmH2O, PEEP was significantly increased from 13.4 ± 3.6 cmH2O at baseline to 15.0 ± 3.4 cmH2O, and the driving pressure was significantly reduced from 13.0 ± 4.8 to 7.9 ± 3.2 cmH2O (both p < 0.05). The PaO2/FiO2 ratio and respiratory-system compliance were not modified after VT reduction. Mild respiratory acidosis occurred, with mean PaCO2 increasing from 43 ± 8 to 53 ± 9 mmHg and mean pH decreasing from 7.39 ± 0.1 to 7.32 ± 0.10 from baseline to 4 ml/kg VT, while the respiratory rate was not altered. Mean extracorporeal blood flow, sweep-gas flow, and CO2 removal were 421 ± 40 ml/min, 10 ± 0.3 L/min, and 51 ± 26 ml/min, respectively. Mean treatment duration was 31 ± 22 h. Day-28 mortality was 15%. CONCLUSIONS: A low-flow ECCO2R device managed with an RRT platform easily and safely enabled very low tidal volume ventilation with moderate increase in PaCO2 in patients with mild-to-moderate ARDS. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02606240. Registered on 17 November 2015.

[Recommendations for the management of patients with short-term mechanical circulatory assistance]. / Recomendaciones de manejo de pacientes con asistencia circulatoria mecánica de corta duración.

There has been a progressive increase in the use of mechanical circulatory support in our country in the last years, mainly in the short-term: as a bridge to cardiac transplant or recovery, which has allowed to rescue patients from a population that concentrates high rates of complications and mortality. This motivated that the Ministry of Health convened a series of experts in the area of heart failure, transplantation and mechanical circulatory support, representatives of different public and private health centers in Chile, with the objective of developing recommendations on the use of short-term mechanical assistance devices, which would serve as a reference for the proper management of these patients. This clinical experts consensus document contains topics related to: definitions and general concepts; indications; contraindications; specific aspects of starting, follow-up and weaning of the devices; process of transfer of patients in circulatory assistance from one center to another and finally criteria of organization, means and competences to be fulfilled by the centers that offer this therapeutic option.

The Society of Thoracic Surgeons, The Society of Cardiovascular Anesthesiologists, and The American Society of ExtraCorporeal Technology: Clinical Practice Guidelines-Anticoagulation During Cardiopulmonary Bypass.

Despite more than a half century of "safe" cardiopulmonary bypass (CPB), the evidence base surrounding the conduct of anticoagulation therapy for CPB has not been organized into a succinct guideline. For this and other reasons, there is enormous practice variability relating to the use and dosing of heparin, monitoring heparin anticoagulation, reversal of anticoagulation, and the use of alternative anticoagulants. To address this and other gaps, The Society of Thoracic Surgeons, the Society of Cardiovascular Anesthesiologists, and the American Society of Extracorporeal Technology developed an Evidence Based Workgroup. This was a group of interdisciplinary professionals gathered to summarize the evidence and create practice recommendations for various aspects of CPB. To date, anticoagulation practices in CPB have not been standardized in accordance with the evidence base. This clinical practice guideline was written with the intent to fill the evidence gap and to establish best practices in anticoagulation therapy for CPB using the available evidence. To identify relevant evidence, a systematic review was outlined and literature searches were conducted in PubMed using standardized medical subject heading (MeSH) terms from the National Library of Medicine list of search terms. Search dates were inclusive of January 2000 to December 2015. The search yielded 833 abstracts, which were reviewed by two independent reviewers. Once accepted into the full manuscript review stage, two members of the writing group evaluated each of 286 full papers for inclusion eligibility into the guideline document. Ninety-six manuscripts were included in the final review. In addition, 17 manuscripts published before 2000 were included to provide method, context, or additional supporting evidence for the recommendations as these papers were considered sentinel publications. Members of the writing group wrote and developed recommendations based on review of the articles obtained and achieved more than two thirds agreement on each recommendation. The quality of information for a given recommendation allowed assessment of the level of evidence as recommended by the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Recommendations were written in the three following areas: (1) heparin dosing and monitoring for initiation and maintenance of CPB; (2) heparin contraindications and heparin alternatives; and (3) reversal of anticoagulation during cardiac operations. It is hoped that this guideline will serve as a resource and will stimulate investigators to conduct more research and to expand on the evidence base on the topic of anticoagulation therapy for CPB.

The Society of Thoracic Surgeons, The Society of Cardiovascular Anesthesiologists, and The American Society of ExtraCorporeal Technology: Clinical Practice Guidelines-Anticoagulation During Cardiopulmonary Bypass.

Despite more than a half century of "safe" cardiopulmonary bypass (CPB), the evidence base surrounding the conduct of anticoagulation therapy for CPB has not been organized into a succinct guideline. For this and other reasons, there is enormous practice variability relating to the use and dosing of heparin, monitoring heparin anticoagulation, reversal of anticoagulation, and the use of alternative anticoagulants. To address this and other gaps, The Society of Thoracic Surgeons, the Society of Cardiovascular Anesthesiologists, and the American Society of Extracorporeal Technology developed an Evidence Based Workgroup. This was a group of interdisciplinary professionals gathered to summarize the evidence and create practice recommendations for various aspects of CPB. To date, anticoagulation practices in CPB have not been standardized in accordance with the evidence base. This clinical practice guideline was written with the intent to fill the evidence gap and to establish best practices in anticoagulation therapy for CPB using the available evidence. To identify relevant evidence, a systematic review was outlined and literature searches were conducted in PubMed using standardized medical subject heading (MeSH) terms from the National Library of Medicine list of search terms. Search dates were inclusive of January 2000 to December 2015. The search yielded 833 abstracts, which were reviewed by two independent reviewers. Once accepted into the full manuscript review stage, two members of the writing group evaluated each of 286 full papers for inclusion eligibility into the guideline document. Ninety-six manuscripts were included in the final review. In addition, 17 manuscripts published before 2000 were included to provide method, context, or additional supporting evidence for the recommendations as these papers were considered sentinel publications. Members of the writing group wrote and developed recommendations based on review of the articles obtained and achieved more than two thirds agreement on each recommendation. The quality of information for a given recommendation allowed assessment of the level of evidence as recommended by the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Recommendations were written in the three following areas: (1) heparin dosing and monitoring for initiation and maintenance of CPB; (2) heparin contraindications and heparin alternatives; and (3) reversal of anticoagulation during cardiac operations. It is hoped that this guideline will serve as a resource and will stimulate investigators to conduct more research and to expand on the evidence base on the topic of anticoagulation therapy for CPB.

Recomendaciones de manejo de pacientes con asistencia circulatoria mecánica de corta duración / Recommendations for the management of patients with short-term mechanical circulatory assistance

There has been a progressive increase in the use of mechanical circulatory support in our country in the last years, mainly in the short-term: as a bridge to cardiac transplant or recovery, which has allowed to rescue patients from a population that concentrates high rates of complications and mortality. This motivated that the Ministry of Health convened a series of experts in the area of heart failure, transplantation and mechanical circulatory support, representatives of different public and private health centers in Chile, with the objective of developing recommendations on the use of short-term mechanical assistance devices, which would serve as a reference for the proper management of these patients. This clinical experts consensus document contains topics related to: definitions and general concepts; indications; contraindications; specific aspects of starting, follow-up and weaning of the devices; process of transfer of patients in circulatory assistance from one center to another and finally criteria of organization, means and competences to be fulfilled by the centers that offer this therapeutic option.

Cardiopulmonary Resuscitation in Adults and Children With Mechanical Circulatory Support: A Scientific Statement From the American Heart Association.

Cardiac arrest in patients on mechanical support is a new phenomenon brought about by the increased use of this therapy in patients with end-stage heart failure. This American Heart Association scientific statement highlights the recognition and treatment of cardiovascular collapse or cardiopulmonary arrest in an adult or pediatric patient who has a ventricular assist device or total artificial heart. Specific, expert consensus recommendations are provided for the role of external chest compressions in such patients.

Use of a Modified Cardiopulmonary Bypass Circuit for Suction Embolectomy with the AngioVac Device.

The AngioVac suction cannula and circuit were designed for the percutaneous removal of soft thrombus and emboli in procedures requiring extracorporeal circulatory support. We describe a modification of the AngioVac suction catheter and cardiopulmonary bypass (CPB) circuit to effectively remove thrombus while maintaining the ability to rapidly initiate full CPBs during a medical crisis. This article will discuss the design concepts of the modified circuit as well as procedural protocols and considerations. The design modifications of incorporating an oxygenator, reservoir, and bridge allow for an increased flexibility that allows adaption to veno-venous extracorporeal membrane oxygenation or full CPB support when required for oxygenation or hemodynamic support.

The Society of Thoracic Surgeons, The Society of Cardiovascular Anesthesiologists, and The American Society of ExtraCorporeal Technology: Clinical Practice Guidelines for Cardiopulmonary Bypass--Temperature Management During Cardiopulmonary Bypass.

UNLABELLED: In order to improve our understanding of the evidence-based literature supporting temperature management during adult cardiopulmonary bypass, The Society of Thoracic Surgeons, the Society of Cardiovascular Anesthesiology and the American Society of ExtraCorporeal Technology tasked the authors to conduct a review of the peer-reviewed literature, including: 1) optimal site for temperature monitoring, 2) avoidance of hyperthermia, 3) peak cooling temperature gradient and cooling rate, and 4) peak warming temperature gradient and rewarming rate. Authors adopted the American College of Cardiology/American Heart Association method for development clinical practice guidelines, and arrived at the following recommendations: CLASS I RECOMMENDATIONS: a)The oxygenator arterial outlet blood temperature is recommended to be utilized as a surrogate for cerebral temperature measurement during CPB. (Class I, Level C) b)To monitor cerebral perfusate temperature during warming, it should be assumed that the oxygenator arterial outlet blood temperature under-estimates cerebral perfusate temperature. (Class I, Level C) c)Surgical teams should limit arterial outlet blood temperature to<37°C to avoid cerebral hyperthermia. (Class 1, Level C) d)Temperature gradients between the arterial outlet and venous inflow on the oxygenator during CPB cooling should not exceed 10°C to avoid generation of gaseous emboli. (Class 1, Level C) e)Temperature gradients between the arterial outlet and venous inflow on the oxygenator during CPB rewarming should not exceed 10°C to avoid out-gassing when blood is returned to the patient. (Class 1, Level C) CLASS IIa RECOMMENDATIONS: a)Pulmonary artery or nasopharyngeal temperature recording is reasonable for weaning and immediate post-bypass temperature measurement. (Class IIa, Level C)b)Rewarming when arterial blood outlet temperature ≥30° C: i.To achieve the desired temperature for separation from bypass, it is reasonable to maintain a temperature gradient between arterial outlet temperature and the venous inflow of≤4°C. (Class IIa, Level B) ii.To achieve the desired temperature for separation from bypass, it is reasonable to maintain a rewarming rate≤0.5°C/min. (Class IIa, Level B) NO RECOMMENDATION: No recommendation for a guideline is provided concerning optimal temperature for weaning from CPB due to insufficient published evidence.

Practical guidelines: lung transplantation in patients with cystic fibrosis.

There are no European recommendations on issues specifically related to lung transplantation (LTX) in cystic fibrosis (CF). The main goal of this paper is to provide CF care team members with clinically relevant CF-specific information on all aspects of LTX, highlighting areas of consensus and controversy throughout Europe. Bilateral lung transplantation has been shown to be an important therapeutic option for end-stage CF pulmonary disease. Transplant function and patient survival after transplantation are better than in most other indications for this procedure. Attention though has to be paid to pretransplant morbidity, time for referral, evaluation, indication, and contraindication in children and in adults. This review makes extensive use of specific evidence in the field of lung transplantation in CF patients and addresses all issues of practical importance. The requirements of pre-, peri-, and postoperative management are discussed in detail including bridging to transplant and postoperative complications, immune suppression, chronic allograft dysfunction, infection, and malignancies being the most important. Among the contributors to this guiding information are 19 members of the ECORN-CF project and other experts. The document is endorsed by the European Cystic Fibrosis Society and sponsored by the Christiane Herzog Foundation.

Factores implicados en el desarrollo de vasoplejía tras cirugía cardiaca con circulación extracorpórea. Estudio prospectivo observacional / Factors involved in the development of vasoplegia after cardiac surgery with extracorporeal circulation. A prospective observational study

Objetivo. Investigamos la incidencia y los factores de riesgo asociados al desarrollo de vasoplejía en el postoperatorio inmediato y a las 24 h en pacientes sometidos a cardiocirugía con circulación extracorpórea. La mayoría de los factores de riesgo evidenciados provienen de estudios retrospectivos. Métodos. Entre noviembre de 2011 y mayo de 2012 estudiamos prospectivamente 188 pacientes consecutivos operados de cardiocirugía con circulación extracorpórea. Excluimos intervenciones quirúrgicas de urgencia y de alta complejidad. Evaluamos la vasoplejía en el postoperatorio inmediato y a las 24 h, definida como presiones arteriales medias inferiores a 50 mmHg y perfusión de noradrenalina superior a 0,08 μg/kg/min, monitorizadas con gasto cardiaco y resistencias vasculares sistémicas. Todos se sometieron al mismo protocolo anestésico, tratamiento hemodinámico y de circulación extracorpórea. Resultados. El 48% presentaron vasoplejía en el postoperatorio inmediato y un 34% a las 24 h. Los factores de riesgo para el desarrollo de vasoplejía fueron el uso de inhibidores de la enzima convertidora de la angiotensina, presentar una presión arterial media < 50 mmHg a la entrada en circulación extracorpórea, el tiempo de pinzamiento aórtico y la temperatura mínima durante la circulación extracorpórea. Y 24 h se correlacionó con el uso de inhibidores de la enzima convertidora de la angiotensina y el tiempo de circulación extracorpórea. Conclusión. La incidencia de vasoplejía en estos pacientes es elevada. El uso preoperatorio de inhibidores de la enzima convertidora de la angiotensina y la presión arterial media a la entrada de circulación extracorpórea son factores de riesgo potencialmente controlables, o si el paciente se presenta con ellos, prever el tratamiento o la prevención de la vasoplejía (AU)

Objective. The incidence and risk factors for vasoplegia in the early postoperative period and at 24 h are investigated in patients subjected to cardiopulmonary bypass surgery. Vasoplegia following cardiac surgery with cardiopulmonary bypass is associated with a high morbimortality. The risk factors described emerged from retrospective, non-controlled studies. Methods. Observational prospective study of 188 consecutive patients subjected to cardiac surgery with cardiopulmonary bypass in a single hospital between November 2011 and May 2012. Emergency surgery or complex procedures were excluded. Vasoplegia was assessed during the immediate postoperative period, and at 24 h after surgery, and was defined as a mean arterial pressure below 50 mmHg, and the need for a noradrenaline perfusion of more than 0.08 μg/kg/min, monitored by cardiac output and systemic vascular resistances. The anaesthetic and cardiopulmonary bypass protocols, as well as haemodynamic management, were the same in all patients. Results. Almost half (48%) of patients had vasoplegia in the immediate postoperative period, and 34% at 24 h. Risk factors for immediate vasoplegia development were preoperative use of angiotensin converting enzyme inhibitor drugs, a mean arterial pressure < 50 mmHg immediately after beginning cardiopulmonary bypass, duration of aortic clamping as well as the cardiopulmonary bypass, and minimum temperature in cardiopulmonary bypass. Vasoplegia at 24 h after surgery was correlated to preoperative angiotensin converting enzyme inhibitor drug treatment and cardiopulmonary bypass duration. Conclusion. The incidence of vasoplegia after cardiac surgery with cardiopulmonary bypass is high during the first 24 postoperative hours. Preoperative treatment with angiotensin converting enzyme inhibitor and the mean arterial pressure at the beginning of cardiopulmonary bypass are the more easily controllable risk factors. In patients arriving to surgery with those drugs, treatment or prevention of vasoplejia should be planned (AU)

Hemorragia masiva después de anticoagulación con bivalirudina en 2 casos de pacientes con trasplante cardiaco / Massive haemorrhage after bivalirudin anticoagulation in two heart transplant patients

La trombopenia inducida por heparina es una complicación autoinmunitaria frecuente. Se trata de un estado protrombótico debido a la formación de anticuerpos contra los complejos heparina/factor plaquetario 4. Ante esta situación es necesario el empleo de fármacos alternativos a la heparina para la anticoagulación durante la circulación extracorpórea. Se exponen 2 casos de trasplante cardiaco en los que se empleó bivalirudina como anticoagulante durante la circulación extracorpórea. En ambos pacientes se observó la aparición de complicaciones hemorrágicas severas. Es necesario mejorar el diagnóstico de la trombopenia inducida por heparina y desarrollar protocolos de empleo de nuevos fármacos alternativos a la heparina. Por ello revisamos los protocolos de actuación y las alternativas terapéuticas a la heparina(AU)

Heparin-induced thrombopenia is a common autoimmune complication. It is a prothrombotic state due to the formation of antibodies against heparin/platelet factor 4 complexes. In this situation drugs other than heparin must be used for anticoagulation during extracorporeal circulation (bypass) surgery. Two cases of heart transplantation are presented in whom bivalirudin was used as an anticoagulant during the cardiopulmonary bypass. Severe bleeding complications were observed in both patients. The diagnosis of heparin-induced thrombopenia needs to be improved, as well as the development of protocols for using new drugs other than heparin. For this reason, we have reviewed current protocols and alternative therapies to heparin(AU)