Reexploration for hemorrhage following coronary artery bypass grafting: incidence and risk factors. Northern New England Cardiovascular Disease Study Group

The effectiveness of cell salvage in extracorporeal circulation surgeries in relation to use of health resources after use: A systematic review and meta-analysis

Background

Alternatives to allogeneic blood transfusions are sought for resource management reasons and it is necessary to investigate the efficiency and efficacy on Cell Salvage use. The objective of this study is to analyze the effectiveness of the Cell Salvage system in addressing factors related to healthcare service utilization that may lead to increased healthcare expenditure.

Methods

A systematic review with meta-analysis was conducted through literature search in Medline, CINAHL, Scopus, Web of Science, and Cochrane Library. Inclusion criteria were studies in English/Spanish, without year restriction and Randomized Controlled Trials design, conducted in adults.

Results

Twenty-six studies were included in the systematic review, involving a total of 4781 patients (nexperimental group = 2365; ncontrol group = 2416). Significant differences favored the Cell Salvage system in units of transfused Red Blood Cells, in terms of units (p = 0.04; SMD = -0.42 95 % CI = -0.83 to -0.02) and individuals (p = 0.001; RR = 0.71, 95 % CI = 0.60 to 0.84) transfused. No significant differences were found in ICU (p = 0.93) and hospital stay duration (p = 0.21), number of reoperations (p = 0.68), and number of units and individuals transfused in terms of platelets (p > 0.05).

Conclusions

Cell Salvage use holds high potential for reducing healthcare costs and indirectly contributing to improving blood and blood product reserves within blood banks. Results obtained thus far do not provide definitive evidence regarding the duration of hospital stay, ICU stay, need for reoperation, or the quantity of transfused platelets. Therefore, it is recommended to increase the number of studies to assess the impact on the economic models of the Cell Salvage system.

Tranexamic acid is associated with improved hemostasis in elderly patients undergoing coronary-artery surgeries in a retrospective cohort study

Background

More elderly patients undergo coronary artery bypass surgery (CABG) than younger patients. Whether tranexamic acid (TA) is still effective and safe in elderly patients undergoing CABG surgeries is still unclear.

Methods

In this study, a cohort of 7,224 patients ≥70 years undergoing CABG surgery were included. Patients were categorized into the no TA group, TA group, high-dose group, and low-dose group according whether TA was administered and the dose administered. The primary endpoint was blood loss and blood transfusion after CABG. The secondary endpoints were thromboembolic events and in-hospital death.

Results

The blood loss at 24 and 48 h and the total blood loss after surgery in patients in the TA group were 90, 90, and 190 ml less than those in the no-TA group, respectively (p < 0.0001). The total blood transfusion was reduced 0.38-fold with TA administration compared to that without TA (OR = 0.62, 95% CI 0.56-0.68, p < 0.0001). Blood component transfusion was also reduced. High-dose TA administration reduced the blood loss by 20 ml 24 h after surgery (p = 0.032) but had no relationship with the blood transfusion. TA increased the risk of perioperative myocardial infarction (PMI) by 1.62-fold [p = 0.003, OR = 1.62, 95% CI (1.18-2.22)] but reduced the hospital stay time in patients who were administered TA compared to that of patients who did not receive TA (p = 0.026).

Conclusion

We revealed that elderly patients undergoing CABG surgeries had better hemostasis after TA administration but increased the risk of PMI. High-dose TA was effective and safe compared with low-dose TA administration in elderly patients undergoing CABG surgery.

Platelet Function Test in Coronary Artery Bypass Grafting: Does It Predict Postoperative Bleeding?

Background Patients undergoing on-pump coronary artery bypass grafting (CABG) are at increased risk of perioperative bleeding and morbidity associated with transfusion as a result of acquired and pharmacologically induced impaired platelet function.

Settings and Design In this a prospective observational study where 52 patients underwent on-pump CABG were analyzed with ROTEM platelet aggregometry.

Materials and Methods Patients were assigned to the “nonexcessive” and “excessive” postoperative bleeding groups according to the postoperative chest tube drainage over 24 hours. Platelet function was assessed by ROTEM platelet using three different activators (arachidonic acid, adenosine diphosphate, and thrombin receptor-activating peptide), at two perioperative time points (T1, before heparinization and T2, 5–10 minutes after protamine administration).

Results There were no differences regarding demographic, pre–cardiopulmonary bypass (CPB) platelet count and antiplatelet therapy. Platelet function was impaired over the time course in all parameters with three different activators. At T2 point, area under the curve (AUC) of all the three platelet indices, that is, TRAPTEM, ARATEM, and ADPTEM, showed significant difference between excessive and nonexcessive groups. At both T1 and T2 points, the amplitude after 6 minutes (A6) and maximum slope (MS) parameters of TRAPTEM, ARATEM, and ADPTEM tests were not significantly different in excessive and nonexcessive groups. At T1 point, AUC was also not significantly different in all three ROTEM platelet tests. Results after protamine administration showed correlation with postoperative chest tube drainage. Cut-off values, as determined by receiver operating characteristics (ROC) analyses, had a consistently weak positive predictive value for all tests at T2 time point, whereas negative predictive values were higher.

Conclusion Platelet function analysis using ROTEM platelet can help to exclude platelet dysfunction as the reason for bleeding after cardiac surgery. Point-of-care platelet function analysis, particularly in combination with viscoelastic testing can reduce perioperative bleeding and transfusion requirements, as well as improve patient outcomes in cardiac surgery.

Effect of anti-platelet therapy on peri-operative blood loss in patients undergoing off-pump coronary artery bypass grafting

Purpose:

The purpose of this study was to review the effect of the pre-operative use of clopidogrel and aspirin on peri-operative bleeding, blood product transfusion, and resource utilization after coronary artery bypass grafting (CABG).

Materials and Methods:

A total of 1200 patients who underwent off-pump CABG (OPCABG) between 2010 and 2012 were retrospectively studied. Patients were divided into three groups: group 1: discontinued aspirin and clopidogrel 6 days prior to surgery (n = 468), group 2: discontinued both drugs 3 to 5 days prior to surgery (n = 621), and group 3: discontinued both drugs 2 days prior to surgery (n = 111). The bleeding pattern and blood product transfusion were studied and compared between the groups. Patients having history of other drugs affecting the coagulation profile, other organ dysfunction, on-pump CABG, and the combined procedure were excluded from the study.

Results:

Group 2 patients had a higher rate of bleeding and a reduced mean value of hemoglobin (Hb) as compared to other groups. The same results were seen in blood and blood product transfusion. Patients of group 2 and group 3 were associated with higher blood loss in terms of drainage at 12 and 24 hours. Post-operatively, this was statistically significant. Re-exploration was statisitically significant in group 3 patients (9.01%) than in group 2 (2.58%) and group 1 (1.07%) patients.

Conclusion:

The pre-operative use of clopidogrel and aspirin in patients undergoing OPCABG showed limited clinical benefits; however, its use significantly increased the risk of bleeding and blood transfusion, thus increasing morbidity and resource utilization. Hence, clopidogrel and aspirin should be stopped at least 6 days prior to surgery.

Impact of COVID-19 on the Prescribing Pattern of Oral Anticoagulants for Atrial Fibrillation After Cardiac Surgery

BACKGROUND

Because of logistic challenges associated with the COVID-19 pandemic, direct oral anticoagulants (DOAC) were favored over warfarin in patients presenting postoperative atrial fibrillation (AF) after cardiac surgery in our institution. Considering the limited evidence supporting the use of DOAC in this context, we sought to evaluate the safety and efficacy of this practice change.

METHODS

A retrospective study was performed with patients from the Quebec City metropolitan area who were hospitalized at the Institut universitaire de cardiologie et de pneumologie de Québec-Université Laval following cardiac surgery and who required oral anticoagulant (OAC) for postoperative AF. The primary objective was to compare the pre- and peri-COVID-19 period for OAC prescribing patterns and the incidence of thrombotic and bleeding events at 3 months post-surgery. The secondary objective was to compare DOAC to warfarin in terms of thrombotic events and bleeding events.

RESULTS

A total of 233 patients were included, 142 from the pre-COVID-19 and 91 from the peri-COVID-19 period, respectively. Both groups had equivalent proportions of preoperative AF (48%) and new-onset postoperative AF (52%). The proportion of patients treated with a DOAC increased from 13% pre-COVID-19 to 82% peri-COVID-19. This change in practice was not associated with a significant difference in the incidence of thrombotic or bleeding events 3 months postoperatively. However, compared to DOAC, warfarin was associated with a higher incidence of major bleeding. Only 1 thrombotic event was reported with warfarin, and none were reported with DOAC.

CONCLUSION

This study suggests that DOAC are an effective and safe alternative to warfarin to treat postoperative AF after cardiac surgery and that this practice can be safely maintained.

Outcome and survival after open heart surgery for adults with congenital heart disease - a single center experience

Introduction. Congenital heart disease (CHD) is the most common type of birth defect today. The adult congenital heart disease (ACHD) population is constantly growing and becoming older and more patients require cardiac surgery. The objective of this study was to review the surgical outcome of the open heart procedures performed on ACHD patients in the last 10 years at Sahlgrenska University Hospital (SUH) through a retrospective descriptive cohort study. Methods. A retrospective data collection was performed for 421 patients who underwent a total of 439 surgical procedures between 2009 and 2018 at the Cardiothoracic department in SUH. The primary outcomes were early (<30 days) and late survival. Secondary outcomes were postoperative complications and independent risk factors for postoperative complications. Results. 30-day mortality was 1.9%. Long-term survival after 3, 5 and 10 years were 96% ± 1, 94.3% ± 1.3 and 92.4% ± 1.8. 82 major complications occurred after 46 procedures (11.6%). The most common major complication was re-exploration due to hemorrhage. Risk factors for major complications were acute surgery and prolonged extracorporeal circulation time. 173 minor complications occurred after 90 procedures (22.5%). The most common minor complication was prolonged intensive care unit stay (>48 h). Conclusion. This study presents satisfactory early and midterm survival. The survival and frequency of major postoperative complications are well in line with what other studies have presented. Patients undergoing resternotomies had no increased risk for mortality or postoperative complications.

Managing the coagulopathy associated with cardiopulmonary bypass

Cardiopulmonary bypass (CPB) has allowed for significant surgical advancements, but accompanying risks can be significant and must be expertly managed. One of the foremost risks is coagulopathic bleeding. Increasing levels of bleeding in cardiac surgical patients at the time of separation from CPB are associated with poor outcomes and mortality. CPB-associated coagulopathy is typically multifactorial and rarely due to inadequate reversal of systemic heparin alone. The components of the bypass circuit induce systemic inflammation and multiple disturbances of the coagulation and fibrinolytic systems. Anticipating coagulopathy is the first step in managing it, and specific patient and procedural risk factors have been identified as predictors of excessive bleeding. Medication management pre-procedure is critical, as patients undergoing cardiac surgery are commonly on anticoagulants or antiplatelet agents. Important adjuncts to avoid transfusion include antifibrinolytics, and perfusion practices such as red cell salvage, sequestration, and retrograde autologous priming of the bypass circuit have varying degrees of evidence supporting their use. Understanding the patient's coagulation status helps target product replacement and avoid larger volume transfusion. There is increasing recognition of the role of point-of-care viscoelastic and functional platelet testing. Common pitfalls in the management of post-CPB coagulopathy include overdosing protamine for heparin reversal, imperfect laboratory measures of thrombin generation that result in normal or near-normal laboratory results in the presence of continued bleeding, and delayed recognition of surgical bleeding. While challenging, the effective management of CPB-associated coagulopathy can significantly improve patient outcomes.

The incidence and effect of resternotomy following cardiac surgery on morbidity and mortality: a 1-year national audit on behalf of the Association of Cardiothoracic Anaesthesia and Critical Care

Over 30,000 adult cardiac operations are carried out in the UK annually. A small number of these patients need to return to theatre in the first few days after the initial surgery, but the exact proportion is unknown. The majority of these resternotomies are for bleeding or cardiac tamponade. The Association of Cardiothoracic Anaesthesia and Critical Care carried out a 1-year national audit of resternotomy in 2018. Twenty-three of the 35 centres that were eligible participated. The overall resternotomy rate (95%CI) within the period of admission for the initial operation in these centres was 3.6% (3.37-3.85). The rate varied between centres from 0.69% to 7.6%. Of the 849 patients who required resternotomy, 127 subsequently died, giving a mortality rate (95%CI) of 15.0% (12.7-17.5). In patients who underwent resternotomy, the median (IQR [range]) length of stay on ICU was 5 (2-10 [0-335]) days, and time to tracheal extubation was 20 (12-48 [0-2880]) hours. A total of 89.3% of patients who underwent resternotomy were transfused red cells, with a median (IQR [range]) of 4 (2-7 [1-1144]) units of red blood cells. The rate (95%CI) of needing renal replacement therapy was 23.4% (20.6-26.5). This UK-wide audit has demonstrated that resternotomy after cardiac surgery is associated with prolonged intensive care stay, high rates of blood transfusion, renal replacement therapy and very high mortality. Further research into this area is required to try to improve patient care and outcomes in patients who require resternotomy in the first 24 h after cardiac surgery.

Reoperation for bleeding following coronary artery bypass surgery with special focus on long-term outcomes

Objectives: We studied the incidence and risk factors of reoperation for bleeding following CABG in a nationwide cohort with focus on long-term complications and survival. Design: A retrospective study on 2060 consecutive, isolated CABG patients operated 2001-2016. Outcome of reoperated patients (n = 130) were compared to non-reoperated ones (n = 1930), including major adverse cardiac and cerebrovascular events (MACCE) and overall survival. Risk factors for reoperation were determined using multivariate logistic regression and a Cox proportional hazards model to assess prognostic factors of long-term survival. Median follow-up was 7.6 years. Results: One hundred thirty patients (6.3%) were reoperated with an annual decrease of 4.1% per year over the study period (p=.04). Major complications (18.5 vs. 9.6%) and 30-day mortality (8.5 vs. 1.9%,) were higher in the reoperation group (p<.001). The use of clopidogrel preoperatively (OR 3.62, 95% CI: 1.90-6.57) and reduced left ventricular ejection fraction (OR 2.23, 95% CI: 1.25-3.77) were the strongest predictors of reoperation, whereas off-pump surgery was associated with a lower reoperation risk (OR 0.44, 95% CI: 0.22-0.85). After exluding patients that died within 30 days postoperatively, no difference in long-term survival or freedom from MACCE was found between groups, and reoperation was not an independent risk factor for long-term mortality in multivariate analysis. Conclusions: The reoperation rate in this study was relatively high but decreased significantly over time. Reoperation was associated with twofold increased risk for major complications and fourfold 30-day mortality, but comparable long-term MACCE and survival rates. This implies that if patients survive the first 30 days following reoperation, their long-term outcome is comparable to non-reoperated patients.

Use of serotonin reuptake inhibitors is not associated with increased bleeding after CABG

OBJECTIVES

Selective serotonin reuptake inhibitors (SSRIs) and serotonin noradrenaline reuptake inhibitors (SNRIs) are the most commonly prescribed antidepressants worldwide. Studies suggest that SSRI/SNRIs can increase bleeding following different surgical procedures, including open heart surgery, but results are conflicting. The objective of this study was to analyse their effects on bleeding after coronary artery bypass grafting (CABG).

METHODS

Of 1237 patients that underwent CABG in Iceland in 2007-2016, 97 (7.8%) used SSRIs/SNRIs preoperatively and were compared to a reference group (n = 1140). Bleeding was assessed using 24-h chest-tube output, number of RBC units transfused and reoperation for bleeding. Thirty-day mortality rates and incidence of complications were also compared.

RESULTS

The two groups were comparable with respect to preoperative and operative variables, with the exception of BMI being significantly higher in the SSRI/SNRI group (30.2 vs. 28.3 kg/m², p < 0.001). No significant differences were observed between groups in 24-h chest-tube output [815 (SSRI/SNRI) vs. 877 ml (reference), p = 0.26], number of RBC units transfused (2.2 vs. 2.2, p = 0.99) or the rate of reoperation for bleeding (4.1% vs. 6.0%, p = 0.61). The incidences of complications and 30-day mortality rate were also similar.

CONCLUSIONS

Using three different criteria, preoperative use of SSRIs/SNRIs was not shown to increase bleeding after CABG. Furthermore, short-term complications as well as 30-day mortality rates did not differ from those of controls. Thus, temporary cessation of SSRI/SNRI treatment prior to CABG to decrease the risk of bleeding is unwarranted.

Absence of perioperative excessive bleeding in on-pump coronary artery bypass grafting cases performed by residents

OBJECTIVES

On-pump coronary artery bypass grafting (CABG) is associated with elevated bleeding risk. Our aim was to evaluate the role of surgical experience in postoperative blood loss.

METHODS

A propensity score-matched analysis was employed to compare on-pump CABG patients operated on by residents and specialists. End points included drainage volume and bleeding severity, as assessed by the Universal Definition of Perioperative Bleeding in cardiac surgery and E-CABG scale.

RESULTS

A total of 212 matched pairs (c-statistics 0.693) were selected from patients operated on by residents (n = 294) and specialists (n = 4394) between October 2012 and May 2018. Patients did not differ in bleeding risk. There were no statistically significant differences in postoperative 6-, 12- and 24-h drainages between subjects operated on by residents and specialists, and there was no between-group difference in rethoracotomy or transfusion rate. There were no differences in Universal Definition of Perioperative Bleeding or E-CABG grades. In June 2018, after a median follow-up of 2.8 years (range 0.1-5.7 years), the overall survival was 94%, with no differences between the patients operated on by residents (95%) and specialists (92%) (P = 0.27).

CONCLUSIONS

Patients undergoing on-pump CABG, when operated on by a resident, are not exposed to an elevated bleeding risk, as compared with patients operated on by experienced surgeons.

Factor XIII activity in patients requiring surgical re-exploration for bleeding after elective cardiac surgery - A prospective case control study

PURPOSE

Surgical re-exploration due to postoperative bleeding is associated with increased morbidity and mortality. The aim of our study was to assess a potential association between the level of postoperative FXIII activity and need for re-exploration due to bleeding in patients undergoing cardiothoracic surgery.

MATERIALS AND METHODS

In our prospective single center observational cohort study, we enrolled patients who underwent elective cardiothoracic surgery. Patients who required re-exploration (RE group) were matched to patients from the study population (non-RE group).

RESULTS

The study included 64 patients, out of a cohort of 678 patients, of whom 32 required surgical re-exploration due to bleeding within the first 24 h. Between patients of the RE and non-RE group, a significantly reduced FXIII activity was observed postoperatively (59.0 vs 71.1; p = .014). Multivariable analysis revealed reduced FXIII activity (p = .048) as a parameter independently associated with surgical re-exploration. Further, reduced FXIII activity (p = .037) and surgical re-exploration (p = .01) were significantly associated with increased 30 day mortality. In multivariable analysis re-exploration was independently associated with increased risk of 30 day mortality (p = .004, HR 9.68).

CONCLUSIONS

Reduced postoperative FXIII activity may be associated with the need for surgical re-exploration. Postoperative assessment of FXIII activity should therefore be considered in patients undergoing elective cardiothoracic surgery.

Recombinant activated factor VII is associated with postoperative thromboembolic adverse events in bleeding after coronary surgery

OBJECTIVES

To evaluate the impact of recombinant activated factor VII (rFVIIa) administration on thromboembolic adverse events (TAEs) in coronary artery bypass grafting (CABG) surgery patients showing postoperative bleeding.

METHODS

From January 2004 to May 2015, 180 CABG surgery patients with postoperative bleeding were included in the study. All patients were managed conservatively and 81 (45%) also received rFVIIa.

RESULTS

Ten patients developed new TAEs (5.6%), 15 (8.3%) were re-explored, 4 (2.2%) had postoperative dialysis and 6 (3.3%) died by day 30 postoperation. Among those with TAEs, 7 experienced cerebrovascular accidents, 2 had myocardial infarction and 1 had pulmonary embolism. A multivariable regression model confirmed rFVIIa as the only independent factor associated with the development of TAEs (odds ratio 6.19, 95% confidence interval 1.197-31.996; P = 0.0296). Fifteen (8.3%) patients were re-explored for bleeding according to our management protocol. No variables to predict the need for re-exploration were identified by the regression model. Chest tube output was statistically significantly lower in patients who received rFVIIa from 3 h [1.9 (Q1-Q3 1.7-2.1) ml/kg/h vs 3.2 (Q1-Q3 3-3.4) ml/kg/h, P = 0.000] through to 12 h after admission [0.6 (Q1-Q3 0.5-0.6) ml/kg/h vs 0.7 (Q1-Q3 0.6-0.9) ml/kg/h, P = 0.000].

CONCLUSIONS

rFVIIa for the treatment of post-CABG bleeding resulted in increased incidence of TAEs in spite of rapid control of bleeding. Hence, rFVIIa should only be used for selected patients and with extreme caution.

Impact of bleeding complications on length of stay and critical care utilization in cardiac surgery patients in England

Background

Bleeding is a significant complication in cardiac surgery and is associated with substantial morbidity and mortality. This study evaluated the impact of bleeding on length of stay (LOS) and critical care utilization in a nationwide sample of cardiac surgery patients treated at English hospitals.

Methods

Retrospective, observational cohort study using linked English Hospital Episode Statistics (HES) and Clinical Practice Research Datalink (CPRD) records for a nationwide sample of patients aged ≥18 years who underwent coronary artery bypass graft (CABG), valve repair/replacement, or aortic operations from January 2010 through February 2016. The primary independent variables were in-hospital bleeding complications and reoperation for bleeding before discharge. Generalized linear models were used to quantify the adjusted mean incremental difference [MID] in post-procedure LOS and critical care days associated with bleeding complications, independent of measured baseline characteristics.

Results

The study included 7774 cardiac surgery patients (3963 CABG; 2363 valve replacement/repair; 160 aortic procedures; 1288 multiple procedures, primarily CABG+valve). Mean LOS was 10.7d, including a mean of 4.2d in critical care. Incidences of in-hospital bleeding complications and reoperation for bleeding were 6.7 and 0.3%, respectively. Patients with bleeding had longer LOS (MID: 3.1d; p < 0.0001) and spent more days in critical care (MID: 2.4d; p < 0.0001). Reoperation for bleeding was associated with larger increases in LOS (MID = 4.0d; p = 0.002) and days in critical care (MID = 3.2d; p = 0.001).

Conclusions

Among English cardiac surgery patients, in-hospital bleeding complications were associated with substantial increases in healthcare utilization. Increased use of evidence-based strategies to prevent and manage bleeding may reduce the clinical and economic burden associated with bleeding complications in cardiac surgery.

Electronic supplementary material

The online version of this article (10.1186/s13019-019-0881-3) contains supplementary material, which is available to authorized users.

Cardiac Surgery Trainees as "Skin-to-Skin" Operating Surgeons: Midterm Outcomes

BACKGROUND

We have previously demonstrated that cardiac surgery trainees can safely perform operations "skin-to-skin" with adequate attending surgeon supervision.

METHODS

We used 100 consecutive cases (82 coronary artery bypass grafts, 9 aortic valve replacements, 7 coronary artery bypass grafts plus aortic valve replacements, 2 others) performed by residents (group R) to match 1:1 by procedure to nonconsecutive cases done by a single attending surgeon (group A) from July 2014 to October 2016. Patients were stratified based on whether the attending surgeon or trainee performed every critical step of the operation skin-to-skin. Outcomes included death, major morbidity, and readmission.

RESULTS

Patients in the two groups were similar with respect to demographic characteristics and comorbidities. The median follow-up time for patients in this study was 28 months (interquartile range: 23 to 35 months). There were seven deaths (3.5%; four in group A, three in group R, p = 0.7). Of the 43 patients (21.5%) who were readmitted during the study term, 27 patients (13.5%) were readmitted for causes related to the operation (11 in group A, 16 in group R, p = 0.02). The most common reasons for readmissions related to the operation were chest pain (n = 11), pleural effusion that required drainage (n = 8), pneumonia (n = 4), and unstable angina that required percutaneous coronary intervention (n = 3). No statistically significant differences were found in reasons for readmission between group A and group R.

CONCLUSIONS

The equivalence of postoperative outcomes previously demonstrated at 30 days persists at midterm follow-up. Our data indicate that trainees can be educated in operative cardiac surgery under the current paradigm without sacrificing outcome quality. It is reasonable to expect academic programs to continue providing trainees with experience as primary operating surgeons.

Development and validation of a measurement system for continuously monitoring postoperative reservoir levels

Following cardiac surgical procedures, multiple drainage systems remain in place inside the patient's chest to prevent the development of pericardial effusion or pneumothorax. Therefore, postoperative bleeding must be diligently observed. Currently, observation of the exudate rate is performed through periodical visual inspection of the reservoir. To improve postoperative monitoring, a measurement system based on load cells was developed to automatically detect bleeding rates. A reservoir retaining bracket was instrumented with a load cell. The signal was digitized by a microcontroller and then processed and displayed on customized software written in LabView. In cases where bleeding rates reach critical levels, the device will automatically sound an alarm. Additionally, the bleeding rate is displayed on the screen with the status of the alarm, as well as the fluid level of the reservoir. These data are all logged to a file. The measurement system has been validated for gain stability and drift, as well as for sensor accuracy, with different in vitro examinations. Additionally, performance of the measurement device was tested in a clinical pilot study on patients recovering from cardiac surgical procedures. The in vitro investigation showed that the monitoring device had excellent gain and drift stability, as well as sensor accuracy, with a resolution of 2.6 mL/h for the bleeding rate. During the clinical examination, bleeding rates of all patients were correctly measured. Continuously recording drainage volume using the developed system was comparable to manual measurements performed every 30 min by a nurse. Implementation of continuous digital measurements could improve patient safety and reduce the workload of medical professionals working in intensive care units.

Impact of Clopidogrel Loading for Coronarography on Bleeding After Urgent First Time CABG

BACKGROUND

Excessive bleeding impairs outcome after coronary artery bypass grafting (CABG). Clopidogrel in combination with aspirin, given before percutaneous coronary intervention, have become the standard for stent thrombosis prevention. Some premedicated patients, however, are found to need surgical treatment, thus platelet inhibition caused by clopidogrel becomes a concern for post operation major bleeding.

AIMS

This study was designed to evaluate the impact of preoperative clopidogrel on bleeding and outcomes after coronary artery bypass graft surgery (CABG).

METHODS

The study represent a observational retrospective analysis of collected data. The follow up of 223 treated with clopidogrel and aspirin and 77 patients not receiving treatment with platelet antagonist 7 days before CABG are analyzed.

RESULTS

The groups were comparable in age, gender, body surface area, preoperative hematocrit, preoperative prothrombin time and prior myocardial infarction. The clopidogrel group had higher12h and 24h mean chest tube output (at 12h mean 519.7ml vs 353.1 ml, p < 0.05, at 24h mean 756.6 ml vs 563.5 ml, p<0.05). Moreover, reoperation for bleeding was 4.5-fold higher in the clopidogrel group (5.9% vs. 1.3%, p <0.01), and more transfusions of red blood cells (3.23U vs 2.6 U, p<0.05), platelets (1.53U vs 1.23U, p<0.01) and fresh frozen plasma (0.84U vs 0.36 U, p<0.01). The clopidogrel group also showed a longer mechanical ventilation time (16.9h vs 12.9 h p = 0.03) and trend towards more prolonged stay in ICU (2.08 days vs 1.7 days p= 0.048).

CONCLUSIONS

Clopidogrel in combination with aspirin before CABG is associated with higher postoperative bleeding, exposure to blood products and morbidity. These findings raise concern regarding the routine administration of clopidogrel before anticipated but undecided coronary stent implantation.

The implication of seniority of supervising attending surgeon on the reexploration rate following elective coronary artery bypass grafting

BACKGROUND AND AIMS

During coronary artery bypass graft (CABG) surgery, the residual hemostasis procedures, from weaning cardiopulmonary bypass to closing sternotomy, are always completed by residents and supervised by attending surgeons. We want to evaluate the teaching effectiveness for residents under the supervision of attending surgeons with different levels of seniority.

MATERIALS AND METHODS

Between January 1st 2001 and December 31st 2010, 2279 consecutive CABG surgeries were performed in our medical center. In total, 83 patients underwent a reexploration for postoperative bleeding. All causes of bleeding were identified and recorded. Competent attending surgeons were defined as having >3 years' experience and young attending surgeons with ≦3 years' experience. We compared the reexploration rate and aimed to identify the common sources of bleeding by the two groups. We also assessed the impact of attending experience on the outcomes and major complications after reexploration.

RESULTS

There were 36 surgical bleeding and 17 non-surgical bleeding in the young group and 16 surgical bleeding and 14 non-surgical bleeding in the competent group. The young group experienced more mediastinal drainage before a reexploration and a longer time interval to a reexploration. However, both are without statistical significance. Furthermore, the young group has a significant longer hospital stay. The most common intra-pericardium surgical bleeding included two-stage cannulation, side branch of the left internal mammary artery (LIMA), and side branch of vein grafts. The most common extra-pericardium surgical bleeding included a puncture hole by sternal wires, LIMA bed, and fragile sternum.

CONCLUSION

Young attending surgeons indeed had both higher incidence of reexploration and surgical bleeding after a CABG. However, the supervisor experience only impacted hospital stay, not major complications or mortality after a reexploration. This might imply the competent attending surgeons provide higher teaching effectiveness for the hemostasis procedure after CABG.

Incidence, risk factors, and prognostic impact of re-exploration for bleeding after cardiac surgery: A retrospective cohort study

BACKGROUND

Postoperative re-exploration for bleeding (RB) is a frequent complication following cardiac surgery. We aim to assess incidence, risk factors, and prognostic significance of RB in a large cohort of cardiac patients.

MATERIALS AND METHODS

We reviewed prospectively collected data for all patients who underwent cardiac surgery at our institution from 2007 to 2015. Logistic regression analysis was used to identify independent predictors of RB and specific outcomes. Propensity matching using a 1:1-ratio compared outcomes of patients who had RB with patients who did not.

RESULTS

During the study period, 7381 patients underwent cardiac operations. Of them, 189 (2.6%) underwent RB. RB was an independent predictor of in-hospital mortality (Odds Ratio (OR):2.62 Confidence Interval (CI):1.38-4.96; p = 0.003), major adverse events (OR:3.94, CI:2.79-5.62; p < 0.001), gastrointestinal events (OR:3.54 CI:1.73-7.24), renal failure (OR:2.44, CI:1.23-4.82), prolonged ventilation (OR:3.83, CI:2.60-5.62, p < 0.001), and sepsis (OR:2.50, CI:1.03-6.04, p = 0.043). Preoperative shock (OR:3.68, CI:1.66-8.13; p = 0.001), congestive heart failure (OR:1.70 CI:1.24-2.32; p = 0.001), and urgent and emergent status (OR:2.27, CI:1.65-3.12 and OR:3.57, CI:1.89-6.75; p < 0.001 for both) were predictors of RB operative mortality. Operative mortality, incidence of major adverse events, gastrointestinal events, and respiratory failure were all significantly higher in the propensity matched RB group (p = 0.050, p < 0.001, p = 0.046, and p < 0.001 respectively).

CONCLUSIONS

RB significantly increases in-hospital mortality and morbidity after cardiac surgery.

A randomized, controlled trial of Veriset™ hemostatic patch in halting cardiovascular bleeding

Background

Obtaining hemostasis during cardiovascular procedures can be a challenge, particularly around areas with a complex geometry or that are difficult to access. While several topical hemostats are currently on the market, most have caveats that limit their use in certain clinical scenarios such as pulsatile arterial bleeding. The aim of this study was to assess the effectiveness and safety of Veriset™ hemostatic patch in treating cardiovascular bleeding.

Methods

Patients (N=90) scheduled for cardiac or vascular surgery at 12 European institutions were randomized 1:1 to treatment with either Veriset™ hemostatic patch (investigational device) or TachoSil^® (control). After application of the hemostat, according to manufacturer instructions for use, time to hemostasis was monitored. Follow-up occurred up to 90 days post-surgery.

Results

Median time to hemostasis was 1.5 min with Veriset™ hemostatic patch, compared to 3.0 min with TachoSil^® (p<0.0001). Serious adverse events within 30 days post-surgery were experienced by 12/44 (27.3%) patients treated with Veriset™ hemostatic patch and 10/45 (22.2%) in the TachoSil^® group (p=0.6295). None of these adverse events were device-related, and no reoperations for bleeding were required within 5 days post-surgery in either treatment group.

Conclusion

This study reinforces the difference in minimum recommended application time between Veriset™ hemostatic patch and TachoSil^® (30 s versus 3 min respectively). When compared directly at 3 min, Veriset™ displayed no significant difference, showing similar hemostasis and safety profiles on the cardiovascular bleeding sites included in this study.

Does topical tranexamic acid reduce postcoronary artery bypass graft bleeding?

Background:

Postoperative bleeding is a common problem in cardiac surgery. We tried to evaluate the effect of topical tranexamic acid (TA) on reducing postoperative bleeding of patients undergoing on-pump coronary artery bypass graft (CABG) surgery.

Materials and Methods:

One hundred and twenty-six isolated primary CABG patients were included in this clinical trial. They were divided blindly into two groups; Group 1, patients receiving 1 g TA diluted in 100 ml normal saline poured into mediastinal cavity before closing the chest and Group 2, patients receiving 100 ml normal saline at the end of operation. First 24 and 48 h chest tube drainage, hemoglobin decrease and packed RBC transfusion needs were compared.

Results:

Both groups were the same in baseline characteristics including gender, age, body mass index, ejection fraction, clamp time, bypass time, and operation length. During the first 24 h postoperatively, mean chest tube drainage in intervention group was 567 ml compared to 564 ml in control group (P = 0.89). Mean total chest tube drainage was 780 ml in intervention group and 715 ml in control group (P = 0.27). There was no significant difference in both mean hemoglobin decrease (P = 0.26) and packed RBC transfusion (P = 0.7). Topical application of 1 g TA diluted in 100 ml normal saline does not reduce postoperative bleeding of isolated on-pump CABG surgery.

Conclusion:

We do not recommend topical usage of 1 g TA diluted in 100 ml normal saline for decreasing blood loss in on-pump CABG patients.

Postoperative Bleeding Following Preoperative Clopidogrel Administration in Patients with Haemoglobin Level Above 110 g/L Undergoing Urgent CABG

INTRODUCTION

Patients with acute coronary syndrome usually receive dual antiplatelet therapy (DAPT) (usually clopidogrel + aspirin) prior to coronary catheterization, and approximately 10% of these patients require coronary artery bypass grafting (CABG). DAPT has favorable effects on prevention of thrombus formation, but it can have deleterious effects on surgical hemostasis. Anaemia, if present, gives additional risk to such patients. The aim of this study was to examine if DAPT affects postoperative bleeding in patients with haemoglobin levels above 110 g/L, who underwent urgent or emergent CABG, less than five days after stopping DAPT therapy.

METHODS

Data were collected prospectively on 122 CABG patients, operated by a surgical team from March 2008 to August 2013. Patients were stratified into two groups: group 1 received DAPT within 5 days of CABG (n=65), and group 2 where DAPT was discontinued for more than 5 days prior to CABG (n=57). All patients were diagnosed with acute coronary syndrome preoperatively, and all of them had haemoglobin levels above 110 g/L. Patients who needed reoperation, combined procedures, or off-pump revascularization were excluded.

RESULTS

There was no hospital mortality. Mean chest tube losses after the surgical revascularization did not differ significantly, but group 1 received a higher quantity of transfused red blood cells and platelets.

CONCLUSION

Urgent and emergent surgical revascularization using extracorporeal circulation in patients with acute coronary syndrome whose preoperative haemoglobin levels are above 110 g/L is a safe and effective procedure. We suggest that, where indicative, one may perform CABG in less than 5 days after the clopidogrel discontinuation.

Diagnostic and therapeutic medical devices for safer blood management in cardiac surgery: systematic reviews, observational studies and randomised controlled trials

Background

Anaemia, coagulopathic bleeding and transfusion are strongly associated with organ failure, sepsis and death following cardiac surgery.

Objective

To evaluate the clinical effectiveness and cost-effectiveness of medical devices used as diagnostic and therapeutic tools for the management of anaemia and bleeding in cardiac surgery.

Methods and results

Workstream 1 – in the COagulation and Platelet laboratory Testing in Cardiac surgery (COPTIC) study we demonstrated that risk assessment using baseline clinical factors predicted bleeding with a high degree of accuracy. The results from point-of-care (POC) platelet aggregometry or viscoelastometry tests or an expanded range of laboratory reference tests for coagulopathy did not improve predictive accuracy beyond that achieved with the clinical risk score alone. The routine use of POC tests was not cost-effective. A systematic review concluded that POC-based algorithms are not clinically effective. We developed two new clinical risk prediction scores for transfusion and bleeding that are available as e-calculators. Workstream 2 – in the PAtient-SPecific Oxygen monitoring to Reduce blood Transfusion during heart surgery (PASPORT) trial and a systematic review we demonstrated that personalised near-infrared spectroscopy-based algorithms for the optimisation of tissue oxygenation, or as indicators for red cell transfusion, were neither clinically effective nor cost-effective. Workstream 3 – in the REDWASH trial we failed to demonstrate a reduction in inflammation or organ injury in recipients of mechanically washed red cells compared with standard (unwashed) red cells.

Limitations

Existing studies evaluating the predictive accuracy or effectiveness of POC tests of coagulopathy or near-infrared spectroscopy were at high risk of bias. Interventions that alter red cell transfusion exposure, a common surrogate outcome in most trials, were not found to be clinically effective.

Conclusions

A systematic assessment of devices in clinical use as blood management adjuncts in cardiac surgery did not demonstrate clinical effectiveness or cost-effectiveness. The contribution of anaemia and coagulopathy to adverse clinical outcomes following cardiac surgery remains poorly understood. Further research to define the pathogenesis of these conditions may lead to more accurate diagnoses, more effective treatments and potentially improved clinical outcomes.

Study registration

Current Controlled Trials ISRCTN20778544 (COPTIC study) and PROSPERO CRD42016033831 (systematic review) (workstream 1); Current Controlled Trials ISRCTN23557269 (PASPORT trial) and PROSPERO CRD4201502769 (systematic review) (workstream 2); and Current Controlled Trials ISRCTN27076315 (REDWASH trial) (workstream 3).

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 5, No. 17. See the NIHR Journals Library website for further project information.

Cost-consequence analysis of different active flowable hemostatic matrices in cardiac surgical procedures

BACKGROUND

A recent retrospective comparative effectiveness study found that use of the FLOSEAL Hemostatic Matrix in cardiac surgery was associated with significantly lower risks of complications, blood transfusions, surgical revisions, and shorter length of surgery than use of SURGIFLO Hemostatic Matrix. These outcome improvements in cardiac surgery procedures may translate to economic savings for hospitals and payers.

OBJECTIVE

The objective of this study was to estimate the cost-consequence of two flowable hemostatic matrices (FLOSEAL or SURGIFLO) in cardiac surgeries for US hospitals.

METHODS

A cost-consequence model was constructed using clinical outcomes from a previously published retrospective comparative effectiveness study of FLOSEAL vs SURGIFLO in adult cardiac surgeries. The model accounted for the reported differences between these products in length of surgery, rates of major and minor complications, surgical revisions, and blood product transfusions. Costs were derived from Healthcare Cost and Utilization Project's National Inpatient Sample (NIS) 2012 database and converted to 2015 US dollars. Savings were modeled for a hospital performing 245 cardiac surgeries annually, as identified as the average for hospitals in the NIS dataset. One-way sensitivity analysis and probabilistic sensitivity analysis were performed to test model robustness.

RESULTS

The results suggest that if FLOSEAL is utilized in a hospital that performs 245 mixed cardiac surgery procedures annually, 11 major complications, 31 minor complications, nine surgical revisions, 79 blood product transfusions, and 260.3 h of cumulative operating time could be avoided. These improved outcomes correspond to a net annualized saving of $1,532,896. Cost savings remained consistent between $1.3m and $1.8m and between $911k and $2.4m, even after accounting for the uncertainty around clinical and cost inputs, in a one-way and probabilistic sensitivity analysis, respectively.

CONCLUSIONS

Outcome differences associated with FLOSEAL vs SURGIFLO that were previously reported in a comparative effectiveness study may result in substantial cost savings for US hospitals.

Myocardial Ischemia Caused by Subepicardial Hematoma

Background Bleeding from bypass anastomosis leakage occurs early after coronary artery bypass grafting. Later, once the anastomosis is covered by intima, spontaneous bleeding is unlikely.

Case Description A 63-year-old male patient developed a pseudoaneurysm-like, subepicardial late-term bleeding resulting in a hematoma that compromised coronary artery flow by increasing extracoronary pressure. This resulted in severe angina pectoris (Canadian Cardiovascular Society IV) and myocardial ischemia within the affected area. After surgical removal of the hematoma and repair of the anastomosis, the patient's symptoms disappeared and no signs of myocardial ischemia were present.

Conclusion Surgical removal is an efficient therapy for subepicardial hematoma inducing myocardial ischemia.

Safety of Recombinant Human Factor XIII in a Cynomolgus Monkey Model of Extracorporeal Blood Circulation

Factor XIII (FXIII) is a thrombin-activated plasma coagulation factor critical for blood clot stabilization and longevity. Administration of exogenous FXIII to replenish depleted stores after major surgery, including cardiopulmonary bypass, may reduce bleeding complications and transfusion requirements. Thus, a model of extracorporeal circulation (ECC) was developed in adult male cynomolgus monkeys ( Macaca fascicularis) to evaluate the nonclinical safety of recombinant human FXIII (rFXIII). The hematological and coagulation profile in study animals during and after 2 h of ECC was similar to that reported for humans during and after cardiopulmonary bypass, including observations of anemia, thrombocytopenia, and activation of coagulation and platelets. Intravenous slow bolus injection of 300 U/kg (2.1 mg/kg) or 1000 U/kg (7 mg/kg) rFXIII after 2 h of ECC was well tolerated in study animals, and was associated with a dose-dependent increase in FXIII activity. No clinically significant effects in respiration, ECG, heart rate, blood pressure, body temperature, clinical chemistry, hematology (including platelet counts), or indicators of thrombosis (thrombin:antithrombin complex and D-Dimer) or platelet activation (platelet factor 4 and beta-thromboglobulin) were related to rFXIII administration. Specific examination of brain, heart, lung, liver, and kidney from rFXIII-treated animals provided no evidence of histopathological alterations suggestive of subclinical hemorrhage or thrombosis. Taken as a whole, the results demonstrate the ECC model suitably replicated the clinical presentation reported for humans during and after cardiopulmonary bypass surgery, and do not suggest significant concerns regarding use of rFXIII in replacement therapy after extracorporeal circulation.

Comparison of low- and high-dose recombinant activated factor VII for postcardiac surgical bleeding

Aim of the Study:

A retrospective observational study to compare safety and efficacy of high and low doses of recombinant activated factor VIIa (rFVIIa) in severe postcardiac surgical bleeding.

Patients and Methods:

From 2004 to 2014, all patients who received rFVIIa for bleeding after cardiac surgery were included and arranged in two groups; Group 1: Low dose (40–50 mcg/kg) (n = 98) and Group 2: High dose (90–120 mcg/kg) (n = 156).

Results:

There was no significant difference in demographic and surgical characteristics of both groups on admission to Cardiac Surgical Intensive Care Unit (CSICU). There was no significant difference between the two groups regarding the reduction in chest tube bleeding in the first 6 h or the transfusion requirement in the 24 h after admission to CSICU. A total of 15 patients (5.9%) had thromboembolic adverse events. (Seven (7.1%) patients in Group 1 compared to 8 (5.1%) patients in Group 2, P = 0.58). There were no significant differences in all-cause mortality at 30 days (2% in Group 1 vs. 3.2% in Group 2, P = 0.6) and at hospital discharge between the two study groups (6.1% in Group 1 vs. 8.3% in Group 2, P = 0.5), respectively. There was no significant difference between the two groups regarding the need for re-exploration, days on mechanical ventilation, CSICU, or hospital stay.

Conclusion:

In this report, Low-dose rFVIIa showed equivalent efficacy and safety to high-dose rFVIIa. Further prospective randomized studies are needed to confirm these findings.

Vascular Injury and Thrombotic Potential: A Note of Caution About Recombinant Factor VIIa

Postoperative hemorrhage following cardiac surgery increases morbidity, mortality, and costs. Several case reports have described the successful use of recombinant factor VIIa to decrease or stop bleeding in patients undergoing cardiac surgery. The mechanism of action of recombinant factor VIIa is thought to be increased site-specific thrombin generation by tissue factor—mediated activation of coagulation or from activated platelets. However, there have also been many reports of thrombotic complications after recombinant factor VIIa administration. Randomized clinical trials and further laboratory studies should help better clarify the efficacy, safety, cost-effectiveness, and optimal dosing of recombinant factor VIIa in the cardiac surgical setting.

Optimal Management of Bleeding Complications After Cardiac Surgery

Patients undergoing cardiac surgery with cardiopulmo nary bypass (CPB) are at increased risk for excessive perioperative blood loss requiring transfusion of blood products. Point-of-care evaluation of platelets, coagu lation factors, and fibrinogen can enable physicians to assess bleeding abnormalities rapidly. They also can facilitate the optimal administration of pharmacologic and transfusion-based therapy and allow physicians to identify patients with surgical bleeding. The ability to reduce the unnecessary use of blood products in this setting has important implications for emerging issues in blood inventory and blood costs. The ability to de crease operative time along with re-exploration rates has important consequences for health care costs in an increasingly managed health care environment. Copyright© 2001 by W.B. Saunders Company.

Bleeding following Coronary Surgery after Preoperative Low-Molecular-Weight Heparin

Low-molecular-weight heparin and acetyl salicylic acid have become an established treatment for unstable angina. A retrospective study on our database of one year was carried out to see what impact preoperative low-molecular-weight heparin versus none had on the postoperative course of 473 patients having coronary surgery exclusively. Apart from the fact that the low-molecular-weight heparin patients had a higher New York Heart Association classification and marginally more grafts, longer bypass and cross-clamp time, the preoperative characteristics and surgery of the two groups were similar. The low-molecular-weight heparin group had twice as many (9.7% versus 4.7%) re-operations for bleeding, 46% versus 26% had blood transfusion and 22.3% versus 12.6% plasma transfusion. The postoperative outcome was otherwise similar. Preoperative treatment of unstable angina with low-molecular-weight heparin carries a definite risk of postoperative bleeding. Although this study did not reveal any serious consequences, bleeding, transfusions and re-operations are associated with infections, wound healing problems and death. The indications and length of treatment with low-molecular-weight heparin in unstable angina patients have to be appropriate and the perioperative management of these patients has to address the bleeding tendency.

Thromboelastogram reduces blood use by inspecting coagulation in heart surgery

OBJECTIVE

Blood transfusion after coronary artery bypass surgery is carried out according to general coagulation tests and blood counts. Our aim was to determine the effects of rotational thromboelastography results on the amount of blood products used in the intraoperative and postoperative periods in coronary artery bypass patients.

METHODS

Our study included 164 patients who underwent coronary artery bypass. A control group was formed from 82 patients picked from hospital records, who had elective coronary artery bypass before the introduction of rotational thromboelastography in our clinic. Blood transfusion was performed in this group according to conventional laboratory data. The study group comprised 82 patients who had elective coronary artery bypass after the introduction of rotational thromboelastography. Blood transfusion was performed in the study group according to rotational thromboelastogram results. The amounts of blood products used in the 2 groups were compared.

RESULTS

There were statistically significant decreases in the intraoperative and postoperative amounts of packed red blood cells (p = 0.012 and p = 0.006) and postoperative whole blood (p = 0.013) used in the study group compared to the control group. Postoperative bleeding was also significantly reduced (p = 0.001) in the study group.

CONCLUSION

Blood transfusion is an important issue after coronary artery bypass, and because of the decreased amount of blood products used, a rotational thromboelastography-based blood transfusion algorithm should be applied in patients undergoing coronary artery bypass.

Impact of retained blood requiring reintervention on outcomes after cardiac surgery

OBJECTIVES

Evacuation of shed blood from around the heart and lungs is a critical requirement for patients in early recovery after cardiac surgery. Incomplete evacuation of shed blood can result in retained blood, which may require subsequent reinterventions to facilitate recovery. The purpose of this study was to determine the incidence of retained blood requiring reintervention and examine the impact on outcomes.

METHODS

We performed a cross-sectional, observational study of all adult patients undergoing cardiac surgery between 2006 and 2013. Subjects who required an intervention to remove blood, blood clot, or bloodily fluid were attributed to the retained blood group. These patients were compared with those not presenting with any of the defined criteria for retained blood. Multivariate regression was performed to account for confounders.

RESULTS

Of 6909 adult patients who underwent cardiac surgery, 1316 (19%) presented with a retained blood-related condition. Retained blood was associated with increased in-hospital mortality (odds ratio [OR], 4.041; 95% confidence interval [CI], 2.589-6.351, P < .001) and a length of stay more than 13 days in the hospital (OR, 3.853; 95% CI, 2.882-5.206; P < .001) and 5 days in the intensive care unit (OR, 4.602; 95% CI, 3.449-6.183; P < .001). The OR for a time of ventilation greater than 23 hours was 3.596 (95% CI, 2.690-4.851; P < .001) and for incidence of renal replacement therapy was 4.449 (95% CI, 3.188-6.226; P < .001).

CONCLUSIONS

Postoperative retained blood is a common outcome and associated with higher in-hospital mortality, longer intensive care unit and hospital stay, and higher incidence of renal replacement therapy. Further research is needed to validate these results and explore interventions to reduce these complications.

Heparin and Protamine Titration Does Not Improve Haemostasis after Cardiac Surgery: A Prospective Randomized Study

Background

Bleeding complications are common in cardiac surgery. Perioperative handling of heparin and protamine may influence the haemostasis. We hypothesized that heparin and protamine dosing based on individual titration curves would improve haemostasis in comparison to standard dosing.

Subjects and Methods

Sixty patients scheduled for first time elective coronary artery bypass grafting or valve surgery were included in a prospective randomized study. The patients were randomized to heparin and protamine dosing with Hepcon HMS Plus device or to standard weight and activated clotting time (ACT) based dosing. Blood samples were collected before and 10 minutes, 2 hours and 4 hours after cardiopulmonary bypass. Primary endpoint was endogenous thrombin potential in plasma 2 hours after surgery as assessed by calibrated automated thrombography. Secondary endpoints included total heparin and protamine doses, whole blood clot formation (thromboelastometry) and post-operative bleeding volume and transfusions. Heparin effect was assessed by measuring anti-Xa activity.

Results

Endogenous thrombin potential and clot formation deteriorated in both groups after surgery without statistically significant intergroup difference. There were no significant differences between the groups in total heparin and protamine doses, heparin effect, or postoperative bleeding and transfusions at any time point. Significant inverse correlations between anti-Xa activity and endogenous thrombin potential were observed 10 min (r = -0.43, p = 0.001), 2 hours (r = -0.66, p<0.001) and 4 hours after surgery (r = -0.58, p<0.001).

Conclusion

In conclusion, the results suggest that perioperative heparin and protamine dosing based on individual titration curves does not improve haemostasis after cardiac surgery. Postoperative thrombin generation capacity correlates to residual heparin effect.

Trial Registration

www.isrctn.comISRCTN14201041.

Genetic variation influences the risk of bleeding after cardiac surgery: novel associations and validation of previous findings

BACKGROUND

Severe post-operative bleeding in cardiac surgery is associated with increased morbidity and mortality. We hypothesized that variation in genetic susceptibility contributes to post-operative bleeding in addition to clinical factors.

METHODS

We included 1036 adults undergoing cardiac surgery with cardiopulmonary bypass. Two different endpoints for excessive post-operative bleeding were used, either defined as blood loss exceeding 2 ml/kg/h the first 4 h post-operatively or a composite including bleeding, transfusions, and reoperations. Twenty-two single nucleotide polymorphisms (SNPs) central in the coagulation and fibrinolysis systems or in platelet membrane receptors were genotyped, focusing on replication of earlier non-replicated findings and exploration of potential novel associations. Using logistic regression, significant SNPs were added to a model with only clinical variables to evaluate whether the genetic variables provided additional information.

RESULTS

Univariate tests identified rs1799809 (located in the promoter region of the PROC gene), rs27646 and rs1062535 (in the ITGA2 gene), rs630014 (in the ABO gene), and rs6048 (in the F9 gene) as significantly associated with excessive post-operative bleeding (P < 0.05, P-values confirmed by permutation). The SNPs were significant also after adjustment with clinical variables, showing almost unchanged odds ratios except for rs1799809 (P = 0.06). Addition of the genetic covariates to a logistic regression model with clinical variables significantly improved the model (P < 0.01).

CONCLUSION

We identified five SNPs associated with post-operative bleeding after cardiac surgery, of which two validated previously published associations. Addition of genetic information to models with only clinical variables improved the models. Our results indicate that common genetic variations significantly influence post-operative bleeding after cardiac surgery.

Simulation trainer for practicing emergent open thoracotomy procedures

BACKGROUND

An emergent open thoracotomy (OT) is a high-risk, low-frequency procedure uniquely suited for simulation training. We developed a cost-effective Cardiothoracic (CT) Surgery trainer and assessed its potential for improving technical and interprofessional skills during an emergent simulated OT.

MATERIALS AND METHODS

We modified a commercially available mannequin torso with artificial tissue models to create a custom CT Surgery trainer. The trainer's feasibility for simulating emergent OT was tested using a multidisciplinary CT team in three consecutive in situ simulations. Five discretely observable milestones were identified as requisite steps in carrying out an emergent OT; namely (1) diagnosis and declaration of a code situation, (2) arrival of the code cart, (3) arrival of the thoracotomy tray, (4) initiation of the thoracotomy incision, and (5) defibrillation of a simulated heart. The time required for a team to achieve each discrete step was measured by an independent observer over the course of each OT simulation trial and compared.

RESULTS

Over the course of the three OT simulation trials conducted in the coronary care unit, there was an average reduction of 29.5% (P < 0.05) in the times required to achieve the five critical milestones. The time required to complete the whole OT procedure improved by 7 min and 31 s from the initial to the final trial-an overall improvement of 40%.

CONCLUSIONS

In our preliminary evaluation, the CT Surgery trainer appears to be useful for improving team performance during a simulated emergent bedside OT in the coronary care unit.

Transfusion strategy: impact of haemodynamics and the challenge of haemodilution

Blood transfusion is associated with increased morbidity and mortality and numerous reports have emphasised the need for reduction. Following this there is increased attention to the concept of patient blood management. However, bleeding is relatively common following cardiac surgery and is further enhanced by the continued antiplatelet therapy policy. Another important issue is that cardiopulmonary bypass leads to haemodilution and a potential blood loss. The basic role of blood is oxygen transport to the organs. The determining factors of oxygen delivery are cardiac output, haemoglobin, and saturation. If oxygen delivery/consumption is out of balance, the compensation mechanisms are simple, as a decrease in one factor results in an increase in one or two other factors. Patients with coexisting cardiac diseases may be of particular risk, but studies indicate that patients with coexisting cardiac diseases tolerate moderate anaemia and may even benefit from a restrictive transfusion regimen. Further it has been shown that patients with reduced left ventricular function are able to compensate with increased cardiac output in response to bleeding and haemodilution if normovolaemia is maintained. In conclusion the evidence supports that each institution establishes its own patient blood management strategy to both conserve blood products and maximise outcome.

Is continuation of antiplatelets until coronary artery bypass safe in Asians?

Background

Controversies have arisen about the risks of discontinuing antiplatelets prior to coronary artery bypass grafting.

Methods

We retrospectively studied the effects of different strategies of antiplatelet discontinuation prior to coronary artery bypass on perioperative bleeding and major adverse cardiovascular events in Asian patients in a single center in Singapore.

Results

402 patients were divided into 4 groups: group A had no antiplatelets before surgery; antiplatelets were stopped for 5–7 days in group B; 2–4 days in group C; and 0–1 day in group D. Compared to group B, group D had longer intensive care unit stays and more intraoperative transfusions of blood ( p = 0.006) and blood products ( p < 0.05). The 1-year major adverse cardiovascular event rate was higher in groups A and D ( p = 0.027). Stopping antiplatelets within 24 h of surgery was one of multiple independent predictors of intraoperative transfusion but not the 1-year major adverse cardiovascular event rate. Patients on aspirin alone had less intraoperative transfusion of platelets and postoperative minor bleeding than those on combined therapy.

Conclusion

Continuation of antiplatelets until 2 days before coronary artery bypass in Asian patients in our institution is unlikely to increase the risks of bleeding and perioperative transfusion. Taking antiplatelets within 24 h of surgery seems to be associated with a higher rate of 1-year major adverse cardiovascular events and bleeding, and an increased risk of blood product transfusion. Thirty-day and 1-year major adverse cardiovascular event rates were higher in patients without antiplatelet treatment.

Factor IX complex for the treatment of severe bleeding after cardiac surgery

BACKGROUND

Previous reports have been published on the use of recombinant Factor VIIa for intractable bleeding after cardiac surgery; however, there is limited information on the use of Factor IX Complex in this population.

METHODS

A retrospective cohort study of adult patients who underwent cardiac surgery and experienced severe postoperative bleeding, defined as a mean chest tube output ≥300 mL/h. Primary outcomes were changes in chest tube output and blood product usage pre- and post-Factor IX Complex administration.

RESULTS

Eleven patients received Factor IX Complex for severe postoperative bleeding. The mean dose of Factor IX Complex was 35 (13-52) units/kg. Chest tube output was significantly reduced after Factor IX Complex administration (mean pre-Factor IX Complex 381 ± 49 mL/h, mean post-Factor IX Complex 151 ± 38 mL/h; P = 0.003). Blood product usage decreased after Factor IX Complex but was not statistically significant (mean pre-Factor IX Complex 373 ± 81 mL/h, mean post-Factor IX Complex 212 ± 48 mL/h; P = 0.669). Adverse events included 1 pulmonary embolism (postoperative day 43) and 2 episodes of acute renal failure requiring dialysis (postoperative days 2 and 5).

CONCLUSIONS

In this small group of patients, Factor IX Complex effectively controlled severe bleeding after cardiac surgery preventing the need for re-exploration.

Process improvement in cardiac surgery: development and implementation of a reoperation for bleeding checklist

OBJECTIVE

High-performing health care organizations differentiate themselves by focusing on continuous process improvement initiatives aimed at enhancing patient outcomes. Reoperation for bleeding is an event associated with considerable morbidity risk. Hence, our primary objective was to develop and implement a formal operative checklist to reduce technical reasons for postoperative bleeding.

METHODS

From January 1, 2011, through June 30, 2012, 5812 cardiac surgical procedures were performed at Cleveland Clinic (Cleveland, OH). A multidisciplinary team developed a simple, easy-to-perform hemostasis checklist based on the most common sites of bleeding. An extensive educational in-service was performed before limited, then universal, checklist implementation. Geometric charts were used to track the number of cases between consecutive reoperations for bleeding. We compared these before (phase 0) and after the first limited implementation phase (phase 1) and the universal implementation phase (phase 2) of the checklist.

RESULTS

The average number of cases between consecutive reoperations for bleeding increased from 32 in phase 0 to 53 in both phase 1 (P = .002) and phase 2 (P = .01).

CONCLUSIONS

A substantial reduction in reoperation for bleeding cases followed implementation of a formalized hemostasis checklist. Our findings underscore the important influence of memory aids that focus attention on surgical techniques to improve patient outcomes in a complex, operative work environment.